Adult influenza vaccination guideline | Feldman | South African ...

African Journals Online (AJOL)

Benefits, harms, costs. Successful vaccination may be effective. in protecting against acute respiratory tract infection, and preventing hospitalisation, complicating pneumonia and death. The vaccine is safe with only occasional reports of anaphylaxis. Contraindications to the vaccine are anaphylactic hypersensitivity to eggs, ...

Vector vaccines for control of avian influenza

Science.gov (United States)

Vaccines play a critical role in the poultry industries efforts at disease control and prevention. However, providing safe, efficacious, and cost-effective vaccines remains a constant issue to the industry. In addition, many viruses undergo mutation in the field requiring vaccine adjustments. Recent...

Cost-effectiveness of a national enterovirus 71 vaccination program in China.

Science.gov (United States)

Wang, Wenjun; Song, Jianwen; Wang, Jingjing; Li, Yaping; Deng, Huiling; Li, Mei; Gao, Ning; Zhai, Song; Dang, Shuangsuo; Zhang, Xin; Jia, Xiaoli

2017-09-01

Enterovirus 71 (EV71) has caused great morbidity, mortality, and use of health service in children younger than five years in China. Vaccines against EV71 have been proved effective and safe by recent phase 3 trials and are now available in China. The purpose of this study was to evaluate the health impact and cost-effectiveness of a national EV71 vaccination program in China. Using Microsoft Excel, a decision model was built to calculate the net clinical and economic outcomes of EV71 vaccination compared with no EV71 vaccination in a birth cohort of 1,000,000 Chinese children followed for five years. Model parameters came from published epidemiology, clinical and cost data. In the base-case, vaccination would annually avert 37,872 cases of hand, foot and mouth disease (HFMD), 2,629 herpangina cases, 72,900 outpatient visits, 6,363 admissions to hospital, 29 deaths, and 945 disability adjusted life years. The break-even price of the vaccine was $5.2/dose. When the price was less than $8.3 or $14.6/dose, the vaccination program would be highly cost-effective or cost-effective, respectively (incremental cost-effectiveness ratio less than or between one to three times China GDP per capita, respectively). In one-way sensitivity analyses, the HFMD incidence was the only influential parameter at the price of $5/dose. Within the price range of current routine vaccines paid by the government, a national EV71 vaccination program would be cost-saving or highly cost-effective to prevent EV71 related morbidity, mortality, and use of health service among children younger than five years in China. Policy makers should consider including EV71 vaccination as part of China's routine childhood immunization schedule.

Comparative effectiveness of different strategies of oral cholera vaccination in bangladesh: a modeling study.

Directory of Open Access Journals (Sweden)

Dobromir T Dimitrov

2014-12-01

Full Text Available Killed, oral cholera vaccines have proven safe and effective, and several large-scale mass cholera vaccination efforts have demonstrated the feasibility of widespread deployment. This study uses a mathematical model of cholera transmission in Bangladesh to examine the effectiveness of potential vaccination strategies.We developed an age-structured mathematical model of cholera transmission and calibrated it to reproduce the dynamics of cholera in Matlab, Bangladesh. We used the model to predict the effectiveness of different cholera vaccination strategies over a period of 20 years. We explored vaccination programs that targeted one of three increasingly focused age groups (the entire vaccine-eligible population of age one year and older, children of ages 1 to 14 years, or preschoolers of ages 1 to 4 years and that could occur either as campaigns recurring every five years or as continuous ongoing vaccination efforts. Our modeling results suggest that vaccinating 70% of the population would avert 90% of cholera cases in the first year but that campaign and continuous vaccination strategies differ in effectiveness over 20 years. Maintaining 70% coverage of the population would be sufficient to prevent sustained transmission of endemic cholera in Matlab, while vaccinating periodically every five years is less effective. Selectively vaccinating children 1-14 years old would prevent the most cholera cases per vaccine administered in both campaign and continuous strategies.We conclude that continuous mass vaccination would be more effective against endemic cholera than periodic campaigns. Vaccinating children averts more cases per dose than vaccinating all age groups, although vaccinating only children is unlikely to control endemic cholera in Bangladesh. Careful consideration must be made before generalizing these results to other regions.

Comparative effectiveness of different strategies of oral cholera vaccination in bangladesh: a modeling study.

Science.gov (United States)

Dimitrov, Dobromir T; Troeger, Christopher; Halloran, M Elizabeth; Longini, Ira M; Chao, Dennis L

2014-12-01

Killed, oral cholera vaccines have proven safe and effective, and several large-scale mass cholera vaccination efforts have demonstrated the feasibility of widespread deployment. This study uses a mathematical model of cholera transmission in Bangladesh to examine the effectiveness of potential vaccination strategies. We developed an age-structured mathematical model of cholera transmission and calibrated it to reproduce the dynamics of cholera in Matlab, Bangladesh. We used the model to predict the effectiveness of different cholera vaccination strategies over a period of 20 years. We explored vaccination programs that targeted one of three increasingly focused age groups (the entire vaccine-eligible population of age one year and older, children of ages 1 to 14 years, or preschoolers of ages 1 to 4 years) and that could occur either as campaigns recurring every five years or as continuous ongoing vaccination efforts. Our modeling results suggest that vaccinating 70% of the population would avert 90% of cholera cases in the first year but that campaign and continuous vaccination strategies differ in effectiveness over 20 years. Maintaining 70% coverage of the population would be sufficient to prevent sustained transmission of endemic cholera in Matlab, while vaccinating periodically every five years is less effective. Selectively vaccinating children 1-14 years old would prevent the most cholera cases per vaccine administered in both campaign and continuous strategies. We conclude that continuous mass vaccination would be more effective against endemic cholera than periodic campaigns. Vaccinating children averts more cases per dose than vaccinating all age groups, although vaccinating only children is unlikely to control endemic cholera in Bangladesh. Careful consideration must be made before generalizing these results to other regions.

Laser vaccine adjuvants. History, progress, and potential.

Science.gov (United States)

Kashiwagi, Satoshi; Brauns, Timothy; Gelfand, Jeffrey; Poznansky, Mark C

2014-01-01

Immunologic adjuvants are essential for current vaccines to maximize their efficacy. Unfortunately, few have been found to be sufficiently effective and safe for regulatory authorities to permit their use in vaccines for humans and none have been approved for use with intradermal vaccines. The development of new adjuvants with the potential to be both efficacious and safe constitutes a significant need in modern vaccine practice. The use of non-damaging laser light represents a markedly different approach to enhancing immune responses to a vaccine antigen, particularly with intradermal vaccination. This approach, which was initially explored in Russia and further developed in the US, appears to significantly improve responses to both prophylactic and therapeutic vaccines administered to the laser-exposed tissue, particularly the skin. Although different types of lasers have been used for this purpose and the precise molecular mechanism(s) of action remain unknown, several approaches appear to modulate dendritic cell trafficking and/or activation at the irradiation site via the release of specific signaling molecules from epithelial cells. The most recent study, performed by the authors of this review, utilized a continuous wave near-infrared laser that may open the path for the development of a safe, effective, low-cost, simple-to-use laser vaccine adjuvant that could be used in lieu of conventional adjuvants, particularly with intradermal vaccines. In this review, we summarize the initial Russian studies that have given rise to this approach and comment upon recent advances in the use of non-tissue damaging lasers as novel physical adjuvants for vaccines.

Application of radiation technology in vaccines development.

Science.gov (United States)

Seo, Ho Seong

2015-07-01

One of the earliest methods used in the manufacture of stable and safe vaccines is the use of chemical and physical treatments to produce inactivated forms of pathogens. Although these types of vaccines have been successful in eliciting specific humoral immune responses to pathogen-associated immunogens, there is a large demand for the development of fast, safe, and effective vaccine manufacturing strategies. Radiation sterilization has been used to develop a variety of vaccine types, because it can eradicate chemical contaminants and penetrate pathogens to destroy nucleic acids without damaging the pathogen surface antigens. Nevertheless, irradiated vaccines have not widely been used at an industrial level because of difficulties obtaining the necessary equipment. Recent successful clinical trials of irradiated vaccines against pathogens and tumors have led to a reevaluation of radiation technology as an alternative method to produce vaccines. In the present article, we review the challenges associated with creating irradiated vaccines and discuss potential strategies for developing vaccines using radiation technology.

Vaccines to Prevent Cancers Not Caused by Viruses - Annual Plan

Science.gov (United States)

We have vaccines against viruses that cause cancer, but what about vaccines for cancers not caused by viruses? Learn about NCI's development of safe and effective vaccines for cancers not caused by infectious agents.

[Development of current smallpox vaccines].

Science.gov (United States)

Maksiutov, R A; Gavrilova, E V; Shchelkunov, S N

2011-01-01

The review gives data on the history of smallpox vaccination and shows the high topicality of designing the current safe vaccines against orthopoxviruses. Four generations of live smallpox, protein subunit, and DNA vaccines are considered. Analysis of the data published leads to the conclusion that it is promising to use the up-to-date generations of safe smallpox subunit or DNA vaccines for mass primary immunization with possible further revaccination with classical live vaccine.

Combined virus-like particle and fusion protein-encoding DNA vaccination of cotton rats induces protection against respiratory syncytial virus without causing vaccine-enhanced disease

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Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Park, Soojin; Kwon, Young-Man; Lee, Youri; Ko, Eun-Ju; Jung, Yu-Jin [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Lee, Jong Seok [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); National Institute of Biological Resources, Incheon (Korea, Republic of); Kim, Yu-Jin [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Lee, Yu-Na; Kim, Min-Chul [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Animal and Plant Quarantine Agency, Gyeonggi-do, Gimcheon, Gyeongsangbukdo (Korea, Republic of); Cho, Minkyoung [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States); Kang, Sang-Moo, E-mail: skang24@gsu.edu [Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences and Department of Biology, Georgia State University, Atlanta, GA (United States)

2016-07-15

A safe and effective vaccine against respiratory syncytial virus (RSV) should confer protection without causing vaccine-enhanced disease. Here, using a cotton rat model, we investigated the protective efficacy and safety of an RSV combination vaccine composed of F-encoding plasmid DNA and virus-like particles containing RSV fusion (F) and attachment (G) glycoproteins (FFG-VLP). Cotton rats with FFG-VLP vaccination controlled lung viral replication below the detection limit, and effectively induced neutralizing activity and antibody-secreting cell responses. In comparison with formalin inactivated RSV (FI-RSV) causing severe RSV disease after challenge, FFG-VLP vaccination did not cause weight loss, airway hyper-responsiveness, IL-4 cytokines, histopathology, and infiltrates of proinflammatory cells such as eosinophils. FFG-VLP was even more effective in preventing RSV-induced pulmonary inflammation than live RSV infections. This study provides evidence that FFG-VLP can be developed into a safe and effective RSV vaccine candidate. - Highlights: • Combined RSV FFG VLP vaccine is effective in inducing F specific responses. • FFG VLP vaccine confers RSV neutralizing activity and viral control in cotton rats. • Cotton rats with RSV FFG VLP vaccination do not show vaccine-enhanced disease. • Cotton rats with FFG VLP vaccine induce F specific antibody secreting cell responses. • Cotton rats with FFG VLP do not induce lung cellular infiltrates and Th2 cytokine.

Combined virus-like particle and fusion protein-encoding DNA vaccination of cotton rats induces protection against respiratory syncytial virus without causing vaccine-enhanced disease

International Nuclear Information System (INIS)

Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Park, Soojin; Kwon, Young-Man; Lee, Youri; Ko, Eun-Ju; Jung, Yu-Jin; Lee, Jong Seok; Kim, Yu-Jin; Lee, Yu-Na; Kim, Min-Chul; Cho, Minkyoung; Kang, Sang-Moo

2016-01-01

A safe and effective vaccine against respiratory syncytial virus (RSV) should confer protection without causing vaccine-enhanced disease. Here, using a cotton rat model, we investigated the protective efficacy and safety of an RSV combination vaccine composed of F-encoding plasmid DNA and virus-like particles containing RSV fusion (F) and attachment (G) glycoproteins (FFG-VLP). Cotton rats with FFG-VLP vaccination controlled lung viral replication below the detection limit, and effectively induced neutralizing activity and antibody-secreting cell responses. In comparison with formalin inactivated RSV (FI-RSV) causing severe RSV disease after challenge, FFG-VLP vaccination did not cause weight loss, airway hyper-responsiveness, IL-4 cytokines, histopathology, and infiltrates of proinflammatory cells such as eosinophils. FFG-VLP was even more effective in preventing RSV-induced pulmonary inflammation than live RSV infections. This study provides evidence that FFG-VLP can be developed into a safe and effective RSV vaccine candidate. - Highlights: • Combined RSV FFG VLP vaccine is effective in inducing F specific responses. • FFG VLP vaccine confers RSV neutralizing activity and viral control in cotton rats. • Cotton rats with RSV FFG VLP vaccination do not show vaccine-enhanced disease. • Cotton rats with FFG VLP vaccine induce F specific antibody secreting cell responses. • Cotton rats with FFG VLP do not induce lung cellular infiltrates and Th2 cytokine.

Update on the Clinical Development of Candidate Malaria Vaccines

National Research Council Canada - National Science Library

Ballou, W. R; Arevalo-Herrera, Myriam; Carucci, Daniel; Richie, Thomas L; Corradin, Giampietro; Diggs, Carter; Druilhe, Pierre; Giersing, Birgitte K; Saul, Allan; Heppner, D. G

2004-01-01

... powerful driver for stimulating clinical development of candidate vaccines for malaria. This new way forward promises to greatly increase the likelihood of bringing a safe and effective vaccine to licensure...

Current barriers, challenges and opportunities for the development of effective STI vaccines: point of view of vaccine producers, biotech companies and funding agencies.

Science.gov (United States)

Dodet, Betty

2014-03-20

Several barriers limit the development of vaccines against sexually transmitted diseases (STIs). Critical scientific information is missing that makes the feasibility and the likelihood of success of vaccines against genital herpes, chlamydia, gonorrhea and trichomonas uncertain: the immunity induced by natural infection is absent or imperfect which seriously limits the capacity to define the types of immune responses that an effective vaccine must induce. Reliable animal models are lacking and a number of crucial clinical questions are still unanswered about the goal of these vaccines and definition of endpoints for clinical trials. In the absence of a clear recognition of the need for vaccines against these diseases, there is no motivation for public or private research and industry to invest in the development of vaccines against STIs. The STI burden should be evaluated not only in terms of mortality and morbidity, but also in terms of economic and psycho-social impact. A global public-private consortium could mobilize the joint efforts of all stakeholders involved in the research, development and implementation of STI vaccines of the public and private sectors; ensure that sufficient resources are applied to R&D of vaccines against these STIs; and provide the pull-push forces that are necessary to overcome the barriers to develop safe and effective vaccines against these diseases. Copyright © 2014. Published by Elsevier Ltd.

Which Dengue Vaccine Approach Is the Most Promising, and Should We Be Concerned about Enhanced Disease after Vaccination? The Path to a Dengue Vaccine: Learning from Human Natural Dengue Infection Studies and Vaccine Trials.

Science.gov (United States)

de Silva, Aravinda M; Harris, Eva

2018-06-01

Dengue virus (DENV) is the most common arthropod-borne viral disease of humans. Although effective vaccines exist against other flaviviral diseases like yellow fever and Japanese encephalitis, dengue vaccine development is complicated by the presence of four virus serotypes and the possibility of partial immunity enhancing dengue disease severity. Several live attenuated dengue vaccines are being tested in human clinical trials. Initial results are mixed, with variable efficacy depending on DENV serotype and previous DENV exposure. Here, we highlight recent discoveries about the human antibody response to DENV and propose guidelines for advancing development of safe and effective dengue vaccines. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

MMR vaccination of children with egg allergy is safe

DEFF Research Database (Denmark)

Andersen, Dorthe Vestergård; Jørgensen, Inger Merete

2013-01-01

Measles, mumps and rubella (MMR) vaccination is part of the Danish Childhood Vaccination Programme. It is known that children may react with anaphylaxis to MMR vaccines containing traces of egg protein. In Denmark, national clinical guidelines recommend that children with egg allergy be referred...... to vaccination at a paediatric ward despite changed recommendations in other countries. The purpose of this study was to determine whether children with egg allergy presented with anaphylactic/allergic reactions to MMR vaccination and to discuss whether Danish recommendations should be upheld....

Varicella zoster vaccines and their implications for development of HSV vaccines

International Nuclear Information System (INIS)

Gershon, Anne A.

2013-01-01

Live attenuated vaccines to prevent varicella and zoster have been available in the US for the past 17 years, with a resultant dramatic decrease in varicella incidence and a predicted future decrease in the incidence of zoster. The pathogenesis and immune responses to varicella zoster virus (VZV) as well as the safety and effectiveness of VZV vaccines are reviewed. The lack of sterilizing immunity provided by VZV vaccines has not prevented them from being safe and effective. Virological and pathological information concerning parallels and differences between VZV and herpes simplex virus (HSV) are highlighted. Although VZV and HSV are distinct pathogens, they appear to have similarities in target organs and immunity that provide an expectation of a high likelihood for the success of vaccination against HSV, and predicted to be similar to that of VZV.

Varicella zoster vaccines and their implications for development of HSV vaccines

Energy Technology Data Exchange (ETDEWEB)

Gershon, Anne A., E-mail: aag1@columbia.edu [Department of Pediatrics, Columbia University College of Physicians and Surgeons, 620W. 168th Street, NY, NY 10032 (United States)

2013-01-05

Live attenuated vaccines to prevent varicella and zoster have been available in the US for the past 17 years, with a resultant dramatic decrease in varicella incidence and a predicted future decrease in the incidence of zoster. The pathogenesis and immune responses to varicella zoster virus (VZV) as well as the safety and effectiveness of VZV vaccines are reviewed. The lack of sterilizing immunity provided by VZV vaccines has not prevented them from being safe and effective. Virological and pathological information concerning parallels and differences between VZV and herpes simplex virus (HSV) are highlighted. Although VZV and HSV are distinct pathogens, they appear to have similarities in target organs and immunity that provide an expectation of a high likelihood for the success of vaccination against HSV, and predicted to be similar to that of VZV.

Flu Vaccine Safety Information

Science.gov (United States)

... Influenza Types Seasonal Avian Swine Variant Pandemic Other Flu Vaccine Safety Information Questions & Answers Language: English (US) ... safety of flu vaccines monitored? Egg Allergy Are flu vaccines safe? Flu vaccines have good safety record. ...

Influenza vaccines: from whole virus preparations to recombinant protein technology.

Science.gov (United States)

Huber, Victor C

2014-01-01

Vaccination against influenza represents our most effective form of prevention. Historical approaches toward vaccine creation and production have yielded highly effective vaccines that are safe and immunogenic. Despite their effectiveness, these historical approaches do not allow for the incorporation of changes into the vaccine in a timely manner. In 2013, a recombinant protein-based vaccine that induces immunity toward the influenza virus hemagglutinin was approved for use in the USA. This vaccine represents the first approved vaccine formulation that does not require an influenza virus intermediate for production. This review presents a brief history of influenza vaccines, with insight into the potential future application of vaccines generated using recombinant technology.

Evaluation of vaccine competition using HVT vector vaccines

Science.gov (United States)

Turkey herpesvirus (HVT) has been widely used as a vaccine for Marek’s disease (MD) since the 1970s. Because HVT is a safe vaccine that is poorly sensitive to interference from maternally derived antibodies, it has seen rising use as a vector for vaccines developed for protection against other comm...

[Pertussis vaccination in pregnancy: Security and effectiveness in the protection of the infant].

Science.gov (United States)

Villena, Rodolfo; Vidal, Pamela; Carrillo, Felipe; Salinas, Mónica

2017-06-01

Whooping cough is an immune preventable disease that can be life threatening. Despite infant immunization starting at 2 month of age, there are many cases and outbreaks in our country and also around the world, with a high risk of mortality specially in infants under 6 month of age. It has been proposed that antenatal vaccination with acellular pertussis component (Tdap) would be useful, safe and effective since it transfers a high antibody rate to the child, reducing the incidence of pertussis in this group by 85%. No higher incidence of adverse effects has been found in pregnant women with this vaccine. This strategy has been implemented in several developed and Latin American countries. The purpose of this manuscript is to review and discuss the benefits of antenatal vaccination with Tdap. It was concluded that maternal immunization with Tdap vaccine should be promoted to prevent infection and associated mortality in the less than 6 months of age by Bordetella pertussis.

Bacterium-like Particles for efficient immune stimulation of existing vaccines and new subunit vaccines in mucosal applications

Directory of Open Access Journals (Sweden)

Natalija eVan Braeckel-Budimir

2013-09-01

Full Text Available The successful development of a mucosal vaccine critically depends on the use of a safe and effective immunostimulant and/or carrier system. This review describes the effectiveness and mode of action of an immunostimulating particle derived from bacteria in mucosal subunit vaccines. The non-living particles, designated Bacterium-like Particles (BLPs are based on the food-grade bacterium Lactococcus lactis. The focus of the overview is on the development of intranasal BLP-based vaccines to prevent diseases caused by influenza and respiratory syncytial virus, and includes a selection of Phase I clinical data for the intranasal FluGEM vaccine.

Vaccines against enteric infections for the developing world

Science.gov (United States)

Czerkinsky, Cecil; Holmgren, Jan

2015-01-01

Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors: —limited knowledge regarding the properties of the gut immune system during early life;—lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines;—lack of correlates/surrogates of mucosal immune protection; and—limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries.There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world's poorest, confer long-term protection and herd immunity, and must be able to contain epidemics. PMID:25964464

Development of a Subunit Vaccine for Contagious Bovine ...

International Development Research Centre (IDRC) Digital Library (Canada)

Their work has set the stage for commercial development of a sub-unit vaccine. ... The sub-unit vaccine will be cost-effective, easy to produce, and safe. How it will make a ... IDRC invites applications for the IDRC Doctoral Research Awards.

The recent progress in RSV vaccine technology.

Science.gov (United States)

Fretzayas, Andrew; Papadopoulou, Anna; Kotzia, Doxa; Moustaki, Maria

2012-12-01

The most effective way to control RSV infection would be the development of an expedient and safe vaccine. Subunit vaccines, live attenuated RSV vaccines, plasmid DNA vaccines have been tested either in human or in mouse models without reaching the ultimate goal of efficacy and safety, at least in humans. Viruses such as adenovirus, sendai virus, measles virus were also used as vectors for the generation of RSV vaccines with promising results in animal models. Recent patents describe new techniques for the generation of candidate vaccines. These patents include virus like particles as vaccine platforms, recombinant RSVs or modified RSV F protein as component of the vaccine. Despite the number of the candidate vaccines, the new RSV vaccines should overcome many obstacles before being established as effective vaccines for the control of RSV infections especially for the young infants who are more susceptible to the virus.

An update on the use of laser technology in skin vaccination

Science.gov (United States)

Chen, Xinyuan; Wang, Ji; Shah, Dilip; Wu, Mei X

2014-01-01

Vaccination via skin often induces stronger immune responses than via muscle. This, in line with potential needle-free, painless delivery, makes skin a very attractive site for immunization. Yet, despite decades of effort, effective skin delivery is still in its infant stage and safe and potent adjuvants for skin vaccination remain largely undefined. We have shown that laser technologies including both fractional and non-fractional lasers can greatly augment vaccine-induced immune response without incurring any significant local and systemic side effects. Laser illumination at specific settings can accelerate the motility of antigen-presenting cells or trigger release of ‘danger’ signals stimulating the immune system. Moreover, several other groups including the authors explore laser technologies for needle-free transcutaneous vaccine delivery. As these laser-mediated resurfacing technologies are convenient, safe and cost-effective, their new applications in vaccination warrant clinical studies in the very near future. PMID:24127871

The effects of anti-vaccine conspiracy theories on vaccination intentions.

Directory of Open Access Journals (Sweden)

Daniel Jolley

Full Text Available The current studies investigated the potential impact of anti-vaccine conspiracy beliefs, and exposure to anti-vaccine conspiracy theories, on vaccination intentions. In Study 1, British parents completed a questionnaire measuring beliefs in anti-vaccine conspiracy theories and the likelihood that they would have a fictitious child vaccinated. Results revealed a significant negative relationship between anti-vaccine conspiracy beliefs and vaccination intentions. This effect was mediated by the perceived dangers of vaccines, and feelings of powerlessness, disillusionment and mistrust in authorities. In Study 2, participants were exposed to information that either supported or refuted anti-vaccine conspiracy theories, or a control condition. Results revealed that participants who had been exposed to material supporting anti-vaccine conspiracy theories showed less intention to vaccinate than those in the anti-conspiracy condition or controls. This effect was mediated by the same variables as in Study 1. These findings point to the potentially detrimental consequences of anti-vaccine conspiracy theories, and highlight their potential role in shaping health-related behaviors.

Developing novel immunogens for a safe and effective Alzheimer's disease vaccine.

Science.gov (United States)

Lemere, Cynthia A

2009-01-01

, a safe and effective active Abeta vaccine would be more cost-effective and more readily available to a larger AD population. We have developed several novel short Abeta immunogens that target the Abeta N-terminus containing a strong B cell epitope while avoiding the Abeta mid-region and C-terminus containing T cell epitopes. These immunogens include dendrimeric Abeta1-15 (16 copies of Abeta1-15 on a lysine antigen tree), 2xAbeta1-15 (a tandem repeat of two lysine-linked Abeta1-15 peptides), and 2xAbeta1-15 with the addition of a three amino acid RGD motif (R-2xAbeta1-15). Intranasal immunization with our short Abeta fragment immunogens and a mucosal adjuvant, mutant Escherichia coli heat-labile enterotoxin LT(R192G), resulted in reduced cerebral Abeta levels, plaque deposition, and gliosis, as well as increased plasma Abeta levels and improved cognition in a transgenic mouse model of AD. Preclinical trials in nonhuman primates, and human clinical trials using similar Abeta immunogens, are now underway. Abeta immunotherapy looks promising but must be made safer and more effective at generating antibody titers in the elderly. It is hoped that these novel immunogens will enhance Abeta antibody generation across a broad population and avoid the adverse events seen in the earlier clinical trial.

Vaccines against enteric infections for the developing world.

Science.gov (United States)

Czerkinsky, Cecil; Holmgren, Jan

2015-06-19

Since the first licensure of the Sabin oral polio vaccine more than 50 years ago, only eight enteric vaccines have been licensed for four disease indications, and all are given orally. While mucosal vaccines offer programmatically attractive tools for facilitating vaccine deployment, their development remains hampered by several factors: -limited knowledge regarding the properties of the gut immune system during early life; -lack of mucosal adjuvants, limiting mucosal vaccine development to live-attenuated or killed whole virus and bacterial vaccines; -lack of correlates/surrogates of mucosal immune protection; and -limited knowledge of the factors contributing to oral vaccine underperformance in children from developing countries. There are now reasons to believe that the development of safe and effective mucosal adjuvants and of programmatically sound intervention strategies could enhance the efficacy of current and next-generation enteric vaccines, especially in lesser developed countries which are often co-endemic for enteric infections and malnutrition. These vaccines must be safe and affordable for the world's poorest, confer long-term protection and herd immunity, and must be able to contain epidemics. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Parent perceptions important for HPV vaccine initiation among low income adolescent girls.

Science.gov (United States)

Staras, Stephanie A S; Vadaparampil, Susan T; Patel, Roshni P; Shenkman, Elizabeth A

2014-10-21

The study aims were to assess the influence of provider recommendations on parental vaccine perceptions and identify the most potent parent vaccine perceptions for HPV vaccine series initiation considering provider recommendation strength. We administered a questionnaire and assessed HPV vaccine claims among a stratified-random sample of parents of 9-17 year old girls enrolled in Florida's Medicaid and the Children's Health Insurance Program. Using multivariate analyses, we evaluated the associations between: (1) parent vaccine perceptions and provider recommendation strength, and (2) parent vaccine perceptions and HPV vaccine series initiation (≥1 vaccine claim or positive parental report) controlling for provider recommendation strength. The majority of the 2422 participating parents agreed that the HPV vaccine was safe (61%), would not make girls more likely to have sex (69%), and prevented cervical cancer (71%). About half (44%) reported receiving a strong provider recommendation. Compared to parents without recommendations, parents with strong recommendations had 2 to 7 times higher odds of agreeing that: vaccines are safe, the HPV vaccine is safe, not concerned about side effects, and the vaccine prevents cervical cancer. Even when considering provider recommendation strength, HPV vaccine series initiation was more likely among girls of parents who agreed rather than disagreed that the HPV vaccine was safe [odds ratio (OR)=5.8, 95% confidence interval (CI)=3.1, 11.1], does not cause sex (OR=2.0, 95% CI=1.2, 3.4), prevents cervical cancer (OR=2.0, 95% CI=1.0, 3.4), and prevents HPV infections (OR=1.8, 95% CI=1.0, 3.0). Parent concerns about HPV vaccine are similar to their concerns about other vaccines. Providers should focus HPV vaccine discussions with parents on vaccine safety and illness prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

Peru-15 (Choleragarde(®)), a live attenuated oral cholera vaccine, is safe and immunogenic in human immunodeficiency virus (HIV)-seropositive adults in Thailand.

Science.gov (United States)

Ratanasuwan, W; Kim, Y H; Sah, B K; Suwanagool, S; Kim, D R; Anekthananon, A; Lopez, A L; Techasathit, W; Grahek, S L; Clemens, J D; Wierzba, T F

2015-09-11

Many areas with endemic and epidemic cholera report significant levels of HIV transmission. According to the World Health Organization (WHO), over 95% of reported cholera cases occur in Africa, which also accounts for nearly 70% of people living with HIV/AIDS globally. Peru-15, a promising single dose live attenuated oral cholera vaccine (LA-OCV), was previously found to be safe and immunogenic in cholera endemic areas. However, no data on the vaccine's safety among HIV-seropositive adults had been collected. This study was a double-blinded, individually randomized, placebo-controlled trial enrolling HIV-seropositive adults, 18-45 years of age, conducted in Bangkok, Thailand, to assess the safety of Peru-15 in a HIV-seropositive cohort. 32 HIV infected subjects were randomized to receive either a single oral dose of the Peru-15 vaccine with a buffer or a placebo (buffer only). No serious adverse events were reported during the follow-up period in either group. The geometric mean fold (GMF) rise in V. cholerae O1 El Tor specific antibody titers between baseline and 7 days after dosing was 32.0 (pcholerae was isolated from the stool of one vaccinee, and found to be genetically identical to the Peru-15 vaccine strain. There were no significant changes in HIV viral load or CD4 T-cell counts between vaccine and placebo groups. Peru-15 was shown to be safe and immunogenic in HIV-seropositive Thai adults. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bioinformatics in New Generation Flavivirus Vaccines

Directory of Open Access Journals (Sweden)

Penelope Koraka

2010-01-01

Full Text Available Flavivirus infections are the most prevalent arthropod-borne infections world wide, often causing severe disease especially among children, the elderly, and the immunocompromised. In the absence of effective antiviral treatment, prevention through vaccination would greatly reduce morbidity and mortality associated with flavivirus infections. Despite the success of the empirically developed vaccines against yellow fever virus, Japanese encephalitis virus and tick-borne encephalitis virus, there is an increasing need for a more rational design and development of safe and effective vaccines. Several bioinformatic tools are available to support such rational vaccine design. In doing so, several parameters have to be taken into account, such as safety for the target population, overall immunogenicity of the candidate vaccine, and efficacy and longevity of the immune responses triggered. Examples of how bio-informatics is applied to assist in the rational design and improvements of vaccines, particularly flavivirus vaccines, are presented and discussed.

Plant-derived vaccine protects target animals against a viral disease

DEFF Research Database (Denmark)

Dalsgaard, Kristian; Uttenthal, Åse; Jones, T.D.

1997-01-01

The successful expression of animal or human virus epitopes on the surface of plant viruses has recently been demonstrated. These chimeric virus particles (CVPs) could represent a cost-effective and safe alternative to conventional animal cell-based vaccines. We report the insertion of oligonucle......The successful expression of animal or human virus epitopes on the surface of plant viruses has recently been demonstrated. These chimeric virus particles (CVPs) could represent a cost-effective and safe alternative to conventional animal cell-based vaccines. We report the insertion...

Now and future influenza vaccines.

Science.gov (United States)

Ruben, F L

1990-03-01

Influenza is a modern day plague. In the young, the clinical picture is classical, but in the elderly, the disease may go unsuspected until complications such as pneumonia develop. Influenza A and B viruses are responsible, and these viruses mutate with great regularity. Antibodies to the HA and NA surface antigens of influenza viruses, both naturally and vaccine induced, are protective. The earliest influenza vaccines were crude, toxic, and ineffective. With modern purification techniques, the egg-grown viruses have been turned into safe, immunogenic, and effective killed-virus vaccines--whole virus and split virus. Surveillance permits the correct virus strains to be incorporated into each new vaccine. Those who have been experiencing the worst effects of influenza have been identified. These individuals need to be immunized each year. In the future, live influenza virus vaccines may offer the benefits of ease of administration and longer-lasting protection. Synthetic peptides, genetically engineered antigens, and even nonantigen (anti-idiotype) vaccines are possible, but such vaccines will require adjuvant enhancement. For the present, greater efforts must be made to use existing influenza vaccines.

Vaccination Perceptions of College Students: With and without Vaccination Waiver.

Science.gov (United States)

Jadhav, Emmanuel D; Winkler, Danielle L; Anderson, Billie S

2018-01-01

The resurgence of vaccine preventable diseases occurs more often among intentionally unvaccinated individuals, placing at direct risk young adults not caught up on vaccinations. The objectives of this study were to characterize the sociodemographic characteristics of young adults with and without vaccination waivers and identify their perceived benefits, barriers, and influencers of vaccination. Young adults ( n  = 964) from a Midwestern rural university responded to a survey (fall 2015-spring 2016) designed to identify their perception toward vaccination. Instrument consistency was measured using the Cronbach α-scores. The Chi-square test was used to test any sociodemographic differences and Mann-Whitney U -tests results for differences between exempt and non-exempt students. Analysis occurred in spring 2017. A little over one-third of young adults with a vaccination waiver were not up to date on their vaccinations, and think that vaccinations can cause autism. The biggest identifiable benefit was effective control against disease. The surveyed young adults ranked the out of pocket cost associated with vaccination as the most important barrier and safe and easy to use vaccines as the most important influencer of vaccination. Young adults who have had a vaccination waiver appear to not be up to date on their vaccinations. Vaccine administration programs, such as university campus clinics, would benefit from addressing perceptions unique to young adults with and without a vaccine waiver. This would subsequently better provide young adults a second shot for getting appropriately caught up on vaccinations.

Progress and pitfalls in Shigella vaccine research

Science.gov (United States)

Barry, Eileen M.; Pasetti, Marcela F.; Sztein, Marcelo B.; Fasano, Alessio; Kotloff, Karen L.; Levine, Myron M.

2013-01-01

Renewed awareness of the significant morbidity and mortality that Shigella causes among young children in developing countries combined with technological innovations in vaccinology has led to the development of novel vaccine strategies in the past five years. Along with advancement of classical vaccines in clinical trials and new sophisticated measurements of immunological responses, much new data has been produced lending promise to the potential for production of safe and effective Shigella vaccines. Herein we review the recent progress in Shigella vaccine development within the framework of persistent obstacles. PMID:23419287

Dengue vaccines: Challenges, development, current status and prospects

Directory of Open Access Journals (Sweden)

A Ghosh

2015-01-01

Full Text Available Infection with dengue virus (DENV is the most rapidly spreading mosquito-borne viral disease in the world. The clinical spectrum of dengue, caused by any of the four serotypes of DENV, ranges from mild self-limiting dengue fever to severe dengue, in the form dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS. Increased rates of hospitalization due to severe dengue, during outbreaks, result in massive economic losses and strained health services. In the absence of specific antiviral therapy, control of transmission of DENV by vector management is the sole method available for decreasing dengue-associated morbidity. Since vector control strategies alone have not been able to satisfactorily achieve reduction in viral transmission, the implementation of a safe, efficacious and cost-effective dengue vaccine as a supplementary measure is a high public health priority. However, the unique and complex immunopathology of dengue has complicated vaccine development. Dengue vaccines have also been challenged by critical issues like lack of animal models for the disease and absence of suitable markers of protective immunity. Although no licensed dengue vaccine is yet available, several vaccine candidates are under phases of development, including live attenuated virus vaccines, live chimeric virus vaccines, inactivated virus vaccines, subunit vaccines, DNA vaccines and viral-vectored vaccines. Although some vaccine candidates have progressed from animal trials to phase II and III in humans, a number of issues regarding implementation of dengue vaccine in countries like India still need to be addressed. Despite the current limitations, collaborative effects of regulatory bodies like World Health Organization with vaccine manufacturers and policy makers, to facilitate vaccine development and standardize field trials can make a safe and efficacious dengue vaccine a reality in near future.

A survey of Vaccine Utilization in a Private Medical Center in Lagos ...

African Journals Online (AJOL)

Safe and effective vaccines have been successful in reducing childhood morbidity and mortality. A study of routine immunization in a private clinic was undertaken to evaluate vaccine utilization. A retrospective evaluation of attendance at a private clinic routine immunization center was done. Quantity of vaccines received ...

Differences in HIV vaccine acceptability between genders

Science.gov (United States)

Kakinami, Lisa; Newman, Peter A.; Lee, Sung-Jae; Duan, Naihua

2010-01-01

The development of safe and efficacious preventive HIV vaccines offers the best long-term hope of controlling the AIDS pandemic. Nevertheless, suboptimal uptake of safe and efficacious vaccines that already exist suggest that HIV vaccine acceptability cannot be assumed, particularly among communities most vulnerable to HIV. The present study aimed to identify barriers and motivators to future HIV vaccine acceptability among low socioeconomic, ethnically diverse men and women in Los Angeles County. Participants completed a cross-sectional survey assessing their attitudes and beliefs regarding future HIV vaccines. Hypothetical HIV vaccine scenarios were administered to determine HIV vaccine acceptability. Two-sided t-tests were performed, stratified by gender, to examine the association between vaccine acceptability and potential barriers and motivators. Barriers to HIV vaccine acceptability differed between men and women. For women, barriers to HIV vaccine acceptability were related to their intimate relationships (p Motivators for women included the ability to conceive a child without worrying about contracting HIV (p Motivators for men included feeling safer with sex partners (p motivator for both men and women (p <0.10). Gender-specific interventions may increase vaccine acceptability among men and women at elevated risk for HIV infection. Among women, interventions need to focus on addressing barriers due to gendered power dynamics in relationships and discrimination in health care. Among men, education that addresses fears and misconceptions about adverse effects of HIV vaccination on health and the importance of vaccination as one component of integrated HIV prevention may increase vaccine acceptability. PMID:18484322

Mucosal vaccines: a paradigm shift in the development of mucosal adjuvants and delivery vehicles.

Science.gov (United States)

Srivastava, Atul; Gowda, Devegowda Vishakante; Madhunapantula, SubbaRao V; Shinde, Chetan G; Iyer, Meenakshi

2015-04-01

Mucosal immune responses are the first-line defensive mechanisms against a variety of infections. Therefore, immunizations of mucosal surfaces from which majority of infectious agents make their entry, helps to protect the body against infections. Hence, vaccinization of mucosal surfaces by using mucosal vaccines provides the basis for generating protective immunity both in the mucosal and systemic immune compartments. Mucosal vaccines offer several advantages over parenteral immunization. For example, (i) ease of administration; (ii) non-invasiveness; (iii) high-patient compliance; and (iv) suitability for mass vaccination. Despite these benefits, to date, only very few mucosal vaccines have been developed using whole microorganisms and approved for use in humans. This is due to various challenges associated with the development of an effective mucosal vaccine that can work against a variety of infections, and various problems concerned with the safe delivery of developed vaccine. For instance, protein antigen alone is not just sufficient enough for the optimal delivery of antigen(s) mucosally. Hence, efforts have been made to develop better prophylactic and therapeutic vaccines for improved mucosal Th1 and Th2 immune responses using an efficient and safe immunostimulatory molecule and novel delivery carriers. Therefore, in this review, we have made an attempt to cover the recent advancements in the development of adjuvants and delivery carriers for safe and effective mucosal vaccine production. © 2015 APMIS. Published by John Wiley & Sons Ltd.

The Meningitis Vaccine Project.

Science.gov (United States)

LaForce, F Marc; Konde, Kader; Viviani, Simonetta; Préziosi, Marie-Pierre

2007-09-03

Epidemic meningococcal meningitis is an important public health problem in sub-Saharan Africa. Current control measures rely on reactive immunizations with polysaccharide (PS) vaccines that do not induce herd immunity and are of limited effectiveness in those under 2 years of age. Conversely, polysaccharide conjugate vaccines are effective in infants and have consistently shown an important effect on decreasing carriage, two characteristics that facilitate disease control. In 2001 the Meningitis Vaccine Project (MVP) was created as a partnership between PATH and the World Health Organization (WHO) with the goal of eliminating meningococcal epidemics in Africa through the development, licensure, introduction, and widespread use of conjugate meningococcal vaccines. Since group A Neisseria meningitidis (N. meningitidis) is the dominant pathogen causing epidemic meningitis in Africa MVP is developing an affordable (US$ 0.40 per dose) meningococcal A (Men A) conjugate vaccine through an innovative international partnership that saw transfer of a conjugation and fermentation technology to a developing country vaccine manufacturer. A Phase 1 study of the vaccine in India has shown that the product is safe and immunogenic. Phase 2 studies have begun in Africa, and a large demonstration study of the conjugate vaccine is envisioned for 2008-2009. After extensive consultations with African public health officials a vaccine introduction plan has been developed that includes introduction of the Men A conjugate vaccine into standard Expanded Programme on Immunization (EPI) schedules but also emphasizes mass vaccination of 1-29 years old to induce herd immunity, a strategy that has been shown to be highly effective when the meningococcal C (Men C) conjugate vaccine was introduced in several European countries. The MVP model is a clear example of the usefulness of a "push mechanism" to finance the development of a needed vaccine for the developing world.

Vaccination Perceptions of College Students: With and without Vaccination Waiver

Directory of Open Access Journals (Sweden)

Emmanuel D. Jadhav

2018-02-01

Full Text Available IntroductionThe resurgence of vaccine preventable diseases occurs more often among intentionally unvaccinated individuals, placing at direct risk young adults not caught up on vaccinations. The objectives of this study were to characterize the sociodemographic characteristics of young adults with and without vaccination waivers and identify their perceived benefits, barriers, and influencers of vaccination.MethodsYoung adults (n = 964 from a Midwestern rural university responded to a survey (fall 2015—spring 2016 designed to identify their perception toward vaccination. Instrument consistency was measured using the Cronbach α-scores. The Chi-square test was used to test any sociodemographic differences and Mann–Whitney U-tests results for differences between exempt and non-exempt students. Analysis occurred in spring 2017.ResultsA little over one-third of young adults with a vaccination waiver were not up to date on their vaccinations, and think that vaccinations can cause autism. The biggest identifiable benefit was effective control against disease. The surveyed young adults ranked the out of pocket cost associated with vaccination as the most important barrier and safe and easy to use vaccines as the most important influencer of vaccination.ConclusionYoung adults who have had a vaccination waiver appear to not be up to date on their vaccinations. Vaccine administration programs, such as university campus clinics, would benefit from addressing perceptions unique to young adults with and without a vaccine waiver. This would subsequently better provide young adults a second shot for getting appropriately caught up on vaccinations.

Brucella suis strain 2 vaccine is safe and protective against heterologous Brucella spp. infections.

Science.gov (United States)

Zhu, Liangquan; Feng, Yu; Zhang, Ge; Jiang, Hui; Zhang, Zhen; Wang, Nan; Ding, Jiabo; Suo, Xun

2016-01-12

Brucellosis is a wide spread zoonotic disease that causes abortion and infertility in mammals and leads to debilitating, febrile illness in humans. Brucella abortus, Brucella melitensis and Brucella suis are the major pathogenic species to humans. Vaccination with live attenuated B. suis strain 2 (S2) vaccine is an essential and critical component in the control of brucellosis in China. The S2 vaccine is very effective in preventing brucellosis in goats, sheep, cattle and swine. However, there are still debates outside of China whether the S2 vaccine is able to provide protection against heterologous virulent Brucella species. We investigated the residual virulence, immunogenicity and protective efficacy of the S2 vaccine in BALB/c mice by determining bacteria persistence in spleen, serum antibody response, cellular immune response and protection against a heterologous virulent challenge. The S2 vaccine was of low virulence as there were no bacteria recovered in spleen four weeks post vaccination. The vaccinated mice developed Brucella-specific IgG in 2-3 weeks, and a burst production of IFN-γ at one week as well as a two-fold increase in TNF-α production. The S2 vaccine protected mice from a virulent challenge by B. melitensis M28, B. abortus 2308 and B. suis S1330, and the S2 vaccinated mice did not develop any clinical signs or tissue damage. Our study demonstrated that the S2 vaccine is of low virulence, stimulates good humoral and cellular immunity and protects animals against infection by heterologous, virulent Brucella species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Oral vaccination of fish

NARCIS (Netherlands)

Embregts, Carmen W.E.; Forlenza, Maria

2016-01-01

The limited number of oral vaccines currently approved for use in humans and veterinary species clearly illustrates that development of efficacious and safe oral vaccines has been a challenge not only for fish immunologists. The insufficient efficacy of oral vaccines is partly due to antigen

Hepatitis A virus among drug users and the role of vaccination: a review.

Directory of Open Access Journals (Sweden)

Fabio eLugoboni

2012-01-01

Full Text Available In countries with advanced economies better health and hygiene conditions, along with the introduction, in some cases, of global vaccination, have relegated most viral hepatitis to marginal social groups and, in particular, drug users (DUs.The availability of safe and effective vaccines for hepatitis A virus (HAV and B (HBV may play a major role in combating this phenomenon.Despite the availability of a safe and effective vaccine for over a decade and the recommendations of international health organizations, vaccinations against HAV among DUs are not as widely known and available as are HBV vaccinations. The purpose of this review article is to present the most significant data in the literature on the prevalence of HAV among DUs and the role of targeted vaccination. To our knowledge, the present article is the first to solely deal with vaccination against HAV in DUs. Immunization after the administration of anti-HAV vaccine has been demonstrated in DUs even if they have responded significantly less than either the GPOP or carriers of chronic liver disease. All the vaccines were well tolerated and adherence to the vaccine schedule was good.Further studies are needed to optimize the timing and doses of vaccine to be administered to DUs, especially to assess adherence and antibody persistence. Vaccination campaigns are feasible among DUs and have proven to be highly cost-effective.

Sex differences in the vaccine-specific and non-targeted effects of vaccines

DEFF Research Database (Denmark)

Flanagan, Katie L; Klein, Sabra L; Skakkebaek, Niels E

2011-01-01

Vaccines have non-specific effects (NSE) on subsequent morbidity and mortality from non-vaccine related infectious diseases. Thus NSE refers to any effect that cannot be accounted for by the induction of immunity against the vaccine-targeted disease. These effects are sex-differential, generally...... being more pronounced in females than males. Furthermore, the NSE are substantial causing greater than fifty percent changes in all cause mortality in certain settings, yet have never been systematically tested despite the fact that millions of children receive vaccines each year. As we strive...... to eliminate infectious diseases through vaccination programmes, the relative impact of NSE of vaccines on mortality is likely to increase, raising important questions regarding the future of certain vaccine schedules. A diverse group of scientists met in Copenhagen to discuss non-specific and sex...

Loss of confidence in vaccines following media reports of infant deaths after hepatitis B vaccination in China.

Science.gov (United States)

Yu, Wenzhou; Liu, Dawei; Zheng, Jingshan; Liu, Yanmin; An, Zhijie; Rodewald, Lance; Zhang, Guomin; Su, Qiru; Li, Keli; Xu, Disha; Wang, Fuzhen; Yuan, Ping; Xia, Wei; Ning, Guijun; Zheng, Hui; Chu, Yaozhu; Cui, Jian; Duan, Mengjuan; Hao, Lixin; Zhou, Yuqing; Wu, Zhenhua; Zhang, Xuan; Cui, Fuqiang; Li, Li; Wang, Huaqing

2016-04-01

China reduced hepatitis B virus (HBV) infection by 90% among children under 5 years old with safe and effective hepatitis B vaccines (HepB). In December 2013, this success was threatened by widespread media reports of infant deaths following HepB administration. Seventeen deaths and one case of anaphylactic shock following HBV vaccination had been reported. We conducted a telephone survey to measure parental confidence in HepB in eleven provinces at four points in time; reviewed maternal HBV status and use of HepB for newborns in birth hospitals in eight provinces before and after the event; and monitored coverage with hepatitis B vaccine and other programme vaccines in ten provinces. HepB from the implicated company was suspended during the investigation, which showed that the deaths were not caused by HepB vaccination. Before the event, 85% respondents regarded domestic vaccines as safe, decreasing to 26.7% during the event. During the height of the crisis, 30% of parents reported being hesitant to vaccinate and 18.4% reported they would refuse HepB. Use of HepB in the monitored provinces decreased by 18.6%, from 53 653 doses the week before the event to 43 688 doses during the week that Biokangtai HepB was suspended. Use of HepB within the first day of life decreased by 10% among infants born to HBsAg-negative mothers, and by 6% among infants born to HBsAg-positive mothers. Vaccine refusal and HepB birth dose rates returned to baseline within 2 months; confidence increased, but remained below baseline. The HBV vaccine event resulted in the suspension of a safe vaccine, which was associated with a decline of parental confidence, and refusal of vaccination. Suspension of a vaccine can lead to loss of confidence that is difficult to recover. Timely and credible investigation, accompanied by proactive outreach to stakeholders and the media, may help mitigate negative impact of future coincidental adverse events following immunization. © The Author 2016; all rights

Pre-clinical evaluation of a novel nanoemulsion-based hepatitis B mucosal vaccine.

Directory of Open Access Journals (Sweden)

Paul E Makidon

2008-08-01

Full Text Available Hepatitis B virus infection remains an important global health concern despite the availability of safe and effective prophylactic vaccines. Limitations to these vaccines include requirement for refrigeration and three immunizations thereby restricting use in the developing world. A new nasal hepatitis B vaccine composed of recombinant hepatitis B surface antigen (HBsAg in a novel nanoemulsion (NE adjuvant (HBsAg-NE could be effective with fewer administrations.Physical characterization indicated that HBsAg-NE consists of uniform lipid droplets (349+/-17 nm associated with HBsAg through electrostatic and hydrophobic interactions. Immunogenicity of HBsAg-NE vaccine was evaluated in mice, rats and guinea pigs. Animals immunized intranasally developed robust and sustained systemic IgG, mucosal IgA and strong antigen-specific cellular immune responses. Serum IgG reached > or = 10(6 titers and was comparable to intramuscular vaccination with alum-adjuvanted vaccine (HBsAg-Alu. Normalization showed that HBsAg-NE vaccination correlates with a protective immunity equivalent or greater than 1000 IU/ml. Th1 polarized immune response was indicated by IFN-gamma and TNF-alpha cytokine production and elevated levels of IgG(2 subclass of HBsAg-specific antibodies. The vaccine retains full immunogenicity for a year at 4 degrees C, 6 months at 25 degrees C and 6 weeks at 40 degrees C. Comprehensive pre-clinical toxicology evaluation demonstrated that HBsAg-NE vaccine is safe and well tolerated in multiple animal models.Our results suggest that needle-free nasal immunization with HBsAg-NE could be a safe and effective hepatitis B vaccine, or provide an alternative booster administration for the parenteral hepatitis B vaccines. This vaccine induces a Th1 associated cellular immunity and also may provide therapeutic benefit to patients with chronic hepatitis B infection who lack cellular immune responses to adequately control viral replication. Long-term stability

A single dose of live-attenuated 638 Vibrio cholerae oral vaccine is safe and immunogenic in adult volunteers in Mozambique

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Hilda María García

2011-12-01

Full Text Available A placebo-controlled randomized, double-blind, clinical trial was carried out to assess the safety, reactogenicity, and immunogenicity of the lyophilized vaccine candidate against cholera derived from the live attenuated 638 Vibrio cholerae O1 El Tor Ogawa strain. One hundred and twenty presumably healthy female and male adult volunteers aged between 18 and 50 years were included. They were from Maputo, Mozambique a cholera endemic area, where, in addition, human immunodeficiency virus (HIV seroprevalence is from 20 to 30%. A dose of 2 x 10 9 colony forming units (CFU was given to 80 subjects and other 40 received only vaccine lyoprotectors as a placebo control. Out-patient follow-up of adverse events was carried out during the following 30 days after vaccination. The immune response was evaluated by the estimation of seroconversion rate and the geometric mean titer (GMT of vibriocidal antibodies in the sera from volunteers that was collected previously, and at days 14 and 21 after immunization. No serious adverse events were reported. The adverse events found in the vaccine group were similar to those of the placebo groups. They were independent from the detection of antibodies against HIV-1, HIV-2, hepatitis (H A; HC and hepatitis B surface antigen. The presence of helminthes did not modify the incidence of adverse events. The 638 vaccine strain was isolated in 37 (46.25% vaccinated volunteer's feces. The peak of the GMT of vibriocidal antibodies in the vaccine group was 9056 versus 39 in the placebo group at 14 days with a total seroconversion of 97.4% at 21 days. The 638 vaccine candidate is safe and immunogenic in a cholera endemic region.

A randomised, double-blind, non-inferiority clinical trial on the safety and immunogenicity of a tetanus, diphtheria and monocomponent acellular pertussis (TdaP) vaccine in comparison to a tetanus and diphtheria (Td) vaccine when given as booster vaccinations to healthy adults

DEFF Research Database (Denmark)

Thierry-Carstensen, Birgit; Jordan, Karina; Uhlving, Hilde Hylland

2012-01-01

Increasing incidence of pertussis in adolescents and adults has stimulated the development of safe and immunogenic acellular pertussis vaccines for booster vaccination of adolescents and adults.......Increasing incidence of pertussis in adolescents and adults has stimulated the development of safe and immunogenic acellular pertussis vaccines for booster vaccination of adolescents and adults....

A safe vaccine (DV-STM-07 against Salmonella infection prevents abortion and confers protective immunity to the pregnant and new born mice.

Directory of Open Access Journals (Sweden)

Vidya Devi Negi

Full Text Available Pregnancy is a transient immuno-compromised condition which has evolved to avoid the immune rejection of the fetus by the maternal immune system. The altered immune response of the pregnant female leads to increased susceptibility to invading pathogens, resulting in abortion and congenital defects of the fetus and a subnormal response to vaccination. Active vaccination during pregnancy may lead to abortion induced by heightened cell mediated immune response. In this study, we have administered the highly attenuated vaccine strain DeltapmrG-HM-D (DV-STM-07 in female mice before the onset of pregnancy and followed the immune reaction against challenge with virulent S. Typhimurium in pregnant mice. Here we demonstrate that DV-STM-07 vaccine gives protection against Salmonella in pregnant mice and also prevents Salmonella induced abortion. This protection is conferred by directing the immune response towards Th2 activation and Th1 suppression. The low Th1 response prevents abortion. The use of live attenuated vaccine just before pregnancy carries the risk of transmission to the fetus. We have shown that this vaccine is safe as the vaccine strain is quickly eliminated from the mother and is not transmitted to the fetus. This vaccine also confers immunity to the new born mice of vaccinated mothers. Since there is no evidence of the vaccine candidate reaching the new born mice, we hypothesize that it may be due to trans-colostral transfer of protective anti-Salmonella antibodies. These results suggest that our vaccine DV-STM-07 can be very useful in preventing abortion in the pregnant individuals and confer immunity to the new born. Since there are no such vaccine candidates which can be given to the new born and to the pregnant women, this vaccine holds a very bright future to combat Salmonella induced pregnancy loss.

Cost Effectiveness of Influenza Vaccine for U.S. Children: Live Attenuated and Inactivated Influenza Vaccine.

Science.gov (United States)

Shim, Eunha; Brown, Shawn T; DePasse, Jay; Nowalk, Mary Patricia; Raviotta, Jonathan M; Smith, Kenneth J; Zimmerman, Richard K

2016-09-01

Prior studies showed that live attenuated influenza vaccine (LAIV) is more effective than inactivated influenza vaccine (IIV) in children aged 2-8 years, supporting the Centers for Disease Control and Prevention (CDC) recommendations in 2014 for preferential LAIV use in this age group. However, 2014-2015 U.S. effectiveness data indicated relatively poor effectiveness of both vaccines, leading CDC in 2015 to no longer prefer LAIV. An age-structured model of influenza transmission and vaccination was developed, which incorporated both direct and indirect protection induced by vaccination. Based on this model, the cost effectiveness of influenza vaccination strategies in children aged 2-8 years in the U.S. was estimated. The base case assumed a mixed vaccination strategy where 33.3% and 66.7% of vaccinated children aged 2-8 years receive LAIV and IIV, respectively. Analyses were performed in 2014-2015. Using published meta-analysis vaccine effectiveness data (83% LAIV and 64% IIV), exclusive LAIV use would be a cost-effective strategy when vaccinating children aged 2-8 years, whereas IIV would not be preferred. However, when 2014-2015 U.S. effectiveness data (0% LAIV and 15% IIV) were used, IIV was likely to be preferred. The cost effectiveness of influenza vaccination in children aged 2-8 years is highly dependent on vaccine effectiveness; the vaccine type with higher effectiveness is preferred. In general, exclusive IIV use is preferred over LAIV use, as long as vaccine effectiveness is higher for IIV than for LAIV. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Oral vaccination of fish

OpenAIRE

Embregts, Carmen W.E.; Forlenza, Maria

2016-01-01

The limited number of oral vaccines currently approved for use in humans and veterinary species clearly illustrates that development of efficacious and safe oral vaccines has been a challenge not only for fish immunologists. The insufficient efficacy of oral vaccines is partly due to antigen breakdown in the harsh gastric environment, but also to the high tolerogenic gut environment and to inadequate vaccine design. In this review we discuss current approaches used to develop oral vaccines fo...

Vaccination and public trust: A model for the dissemination of vaccination behaviour with external intervention

Science.gov (United States)

Dorso, Claudio O.; Medus, Andrés; Balenzuela, Pablo

2017-09-01

Vaccination is widely recognized as the most effective way of immunization against many infectious diseases. However, unfounded claims about supposed side effects of some vaccines have contributed to spread concern and fear among people, thus inducing vaccination refusal. MMR (Measles, Mumps and Rubella) vaccine coverage has undergone an important decrease in a large part of Europe and US as a consequence of erroneously alleged side effects, leading to recent measles outbreaks. There is evidence that clusterization of unvaccinated individuals may lead to epidemics way larger that the ones that might appear in the case that unvaccinated agents are distributed at random in the population. In this work we explore the emergence of those clusters as a consequence of the social interaction driven mainly by homophily, where vaccination behaviour is part of a process of cultural dissemination in the spirit of Axelrod's model. The ingredients of this calculation encompass: (i) interacting agents which are to decide if they vaccinate or not their children, (ii) their interaction with a small subset of stubborn agents who believe that the MMR vaccine is not safe and (iii) government sponsored propaganda trying to convince people of the benefits of vaccination. We find that these clusters, which emerge as a dynamical outcome of the model, are the responsible of the increasing probability of the occurrence of measles outbreaks, even in scenarios where the WHO (World Health Organization) recommendation of 95% vaccine coverage is fulfilled. However, we also illustrate that the mitigating effect of a public health campaign, could effectively reduce the impact and size of outbreaks.

Modeling the cost-effectiveness of infant vaccination with pneumococcal conjugate vaccines in Germany.

Science.gov (United States)

Kuhlmann, Alexander; von der Schulenburg, J-Matthias Graf

2017-04-01

In 2009, the European Medicines Agency granted approval for two higher-valent pneumococcal conjugate vaccines. This study aims to evaluate the cost-effectiveness of universal infant (historical vaccination scheme in infants as well as indirect herd effects and replacement disease. We used German epidemiological data to calculate episodes of IPD, PNE, and AOM, as well as direct and indirect effects of the vaccination. Parameter uncertainty was tested in univariate and probabilistic sensitivity analyses. In the base-case analysis, the ICER of PCV13 versus PCV10 infant vaccination was EUR 9826 per quality-adjusted life-year (QALY) gained or EUR 5490 per life-year (LY) gained from the societal perspective and EUR 3368 per QALY gained or EUR 1882 per LY gained from the perspective of the German statutory health insurance. The results were particularly sensitive to the magnitude of indirect effects of both vaccines. Universal infant vaccination with PCV13 is likely to be a cost-effective intervention compared with PCV10 within the German health care system, if additional net indirect effects of PCV13 vaccination are significant.

HIV-1 vaccines

Science.gov (United States)

Excler, Jean-Louis; Robb, Merlin L; Kim, Jerome H

2014-01-01

The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure. PMID:24637946

Bioinformatics analysis of Brucella vaccines and vaccine targets using VIOLIN.

Science.gov (United States)

He, Yongqun; Xiang, Zuoshuang

2010-09-27

Brucella spp. are Gram-negative, facultative intracellular bacteria that cause brucellosis, one of the commonest zoonotic diseases found worldwide in humans and a variety of animal species. While several animal vaccines are available, there is no effective and safe vaccine for prevention of brucellosis in humans. VIOLIN (http://www.violinet.org) is a web-based vaccine database and analysis system that curates, stores, and analyzes published data of commercialized vaccines, and vaccines in clinical trials or in research. VIOLIN contains information for 454 vaccines or vaccine candidates for 73 pathogens. VIOLIN also contains many bioinformatics tools for vaccine data analysis, data integration, and vaccine target prediction. To demonstrate the applicability of VIOLIN for vaccine research, VIOLIN was used for bioinformatics analysis of existing Brucella vaccines and prediction of new Brucella vaccine targets. VIOLIN contains many literature mining programs (e.g., Vaxmesh) that provide in-depth analysis of Brucella vaccine literature. As a result of manual literature curation, VIOLIN contains information for 38 Brucella vaccines or vaccine candidates, 14 protective Brucella antigens, and 68 host response studies to Brucella vaccines from 97 peer-reviewed articles. These Brucella vaccines are classified in the Vaccine Ontology (VO) system and used for different ontological applications. The web-based VIOLIN vaccine target prediction program Vaxign was used to predict new Brucella vaccine targets. Vaxign identified 14 outer membrane proteins that are conserved in six virulent strains from B. abortus, B. melitensis, and B. suis that are pathogenic in humans. Of the 14 membrane proteins, two proteins (Omp2b and Omp31-1) are not present in B. ovis, a Brucella species that is not pathogenic in humans. Brucella vaccine data stored in VIOLIN were compared and analyzed using the VIOLIN query system. Bioinformatics curation and ontological representation of Brucella vaccines

How Safe Is Measles Immunization Of Sick Children? | Ogbonna ...

African Journals Online (AJOL)

A prospective study to ascertain how safe is maeales immunization of sick children was carried out in Jos University Teaching Hospital, Family Health Centre. Out of 125 children who were vaccinated against measles 17(16%) were sick at the time of vaccination. Two (12%) of the sick children had post vaccination reaction.

Effect of vaccination with N-glycolyl GM3/VSSP vaccine by subcutaneous injection in patients with advanced cutaneous melanoma

International Nuclear Information System (INIS)

Osorio, Marta; Gracia, Elias; Reigosa, Edmundo; Hernandez, Julio; Torre, Ana de la; Saurez, Giselle; Perez, Kirenia; Viada, Carmen; Cepeda, Meylán; Carr, Adriana; Ávila, Yisel; Rodríguez, Migdalia; Fernandez, Luis E

2012-01-01

NeuGc-containing gangliosides have been described in melanoma cells and are an attractive target for cancer immunotherapy because they are minimally or not expressed in normal human tissues. Melanoma patients treated with a vaccine based on N-glycolyl gangliosides have shown benefit in progression free survival and overall survival. We conducted a multicenter Phase I/II clinical trial in patients with metastatic cutaneous melanoma treated with the N-gycolyl GM3/very-small-size proteoliposomes vaccine by the subcutaneous route. Selecting the optimal biological dose of the vaccine was the principal objective based on immunogenicity, efficacy, and safety results. Six dose levels were studied and the treatment schedule consisted of five doses administered every 2 weeks and then monthly until 15 doses had been given. Dose levels evaluated were 150, 300, 600, 900, 1200, and 1500 μg with five patients included in each dose level except the 900 μg dose (n = 10). Immunogenicity was determined by antibody titers generated in patients after vaccination. Antitumor effect was measured by response criteria of evaluation in solid tumors and safety was evaluated by common toxicity criteria of adverse events. The vaccine was safe and immunogenic at all doses levels. The most frequent adverse events related to vaccination were mild to moderate injection site reactions and flu-like symptoms. Vaccination induced specific anti-NeuGcGM3 immunoglobulin M and immunoglobulin G antibody responses in all patients. Disease control (objective response or stable disease) was obtained in 38.46% of patients. Global median overall survival was 20.20 months. Two patients achieved overall survival duration of about 4 and 5 years, respectively. The 900 μg dose resulted in overall survival duration of 19.40 months and was selected as the biological optimal dose

The effect of cool water pack preparation on vaccine vial temperatures in refrigerators.

Science.gov (United States)

Goldwood, Geneva; Diesburg, Steven

2018-01-02

Cool water packs are a useful alternative to ice packs for preventing unintentional freezing of vaccines during outreach in some situations. Current guidelines recommend the use of a separate refrigerator for cooling water packs from ambient temperatures to prevent possible heat degradation of adjacent vaccine vials. To investigate whether this additional equipment is necessary, we measured the temperatures that vaccine vials were exposed to when warm water packs were placed next to vials in a refrigerator. We then calculated the effect of repeated vial exposure to those temperatures on vaccine vial monitor status to estimate the impact to the vaccine. Vials were tested in a variety of configurations, varying the number and locations of vials and water packs in the refrigerator. The calculated average percentage life lost during a month of repeated warming ranged from 20.0% to 30.3% for a category 2 (least stable) vaccine vial monitor and from 3.8% to 6.0% for a category 7 (moderate stability) vaccine vial monitor, compared to 17.0% for category 2 vaccine vial monitors and 3.1% for category 7 vaccine vial monitors at a constant 5 °C. The number of vials, number of water packs, and locations of each impacted vial warming and therefore percentage life lost, but the vaccine vial monitor category had a higher impact on the average percentage life lost than any of the other parameters. The results suggest that damage to vaccines from repeated warming over the course of a month is not certain and that cooling water packs in a refrigerator where vaccines are being stored may be a useful practice if safe procedures are established. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

INTRALESIONAL MEASLES, MUMPS AND RUBELLA (MMR VACCINE-AN EFFECTIVE THERAPEUTIC TOOL IN THE TREATMENT OF WART

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Raju

2015-11-01

Full Text Available BACKGROUND: Warts are common cutaneous viral infection. Various therapeutic modalities have been using in treatment of wart, but none of them are standardised. Immunotherapy is new current approach in the treatment of wart. AIMS: To know the efficacy and safety profile of Measles Mumps Rubella (MMR Vaccine in the treatment of wart. METHODS: MMR vaccine was injected into a largest single wart intralesionally and subsequent injections given every 2 weeks apart for about 3 to 5 times. Every month followup of patients was done to know the clearance of wart. RESULTS: Complete remission of warts seen in 70.4% of patients, partial remission seen in 22.2% and no response was seen in 7.4% of patients. No serious adverse side effects were seen in the current study. CONCLUSION: MMR vaccine can be considered as a safe, effective, inexpensive intralesional immunotherapeutic modality in the treatment of wart.

Safe injection practice among health care workers, Gharbiya, Egypt.

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Ismail, Nanees A; Aboul Ftouh, Aisha M; El Shoubary, Waleed H

2005-01-01

A cross-sectional study was conducted in 25 health care facilities in Gharbiya governorate to assess safe injection practices among health care workers (HCWs). Two questionnaires, one to collect information about administrative issues related to safe injection and the other to collect data about giving injections, exposure to needle stick injuries, hepatitis B vaccination status and safe injection training. Practices of injections were observed using a standardized checklist. The study revealed that there was lack of both national and local infection control policies and lack of most of the supplies needed for safe injection practices. Many safe practices were infrequent as proper needle manipulation before disposal (41%), safe needle disposal (47.5%), reuse of used syringe & needle (13.2%) and safe syringe disposal (0%). Exposure to needle stick injuries were common among the interviewed HCWs (66.2%) and hand washing was the common post exposure prophylaxis measure (63.4%). Only 11.3% of HCWs had full course hepatitis B vaccination. Infection control -including safe injections- training programs should be afforded to all HCWs.

VALUE OF UNIVERSAL CHILDHOOD VARICELLA VACCINATION IN SLOVENIA

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Jerneja Ahčan

2002-11-01

Full Text Available Background. In 1974 effective and safe vaccine against varicella was developed. Vaccination is recomended for universal childhood immunisation in some of west European countries and in the United States. The aim of the study was to perform economic analysis of universal childhood vaccination against varicella in Slovenia.Methods. We examined hypothetical birth cohort of 5800 persons followed from birth to their 30th birthday and calculated the cost-benefit ratio for varicella vaccination program. We assumed that one dose of vaccine would be given to 15-monthold children along with measles, mumps and rubella vaccination. It was also assumed that 95% of children would be vaccinated, that vaccine efficacy would be 90%, that vaccine induced immunity would be lifelong and that the program would have no effect on either the incidence rate or severity of herpes zoster. For both disease and vaccine we measured the direct medical cost and indirect cost.Results. Indirect cost represented major part compared to medical cost. The benefit to cost ratio was 0.89.Conclusions. Considering major assumptions in this analysis, there is no financial benefits from vaccinating all children against varicella in our country.

Current state and challenges in developing oral vaccines.

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Vela Ramirez, Julia E; Sharpe, Lindsey A; Peppas, Nicholas A

2017-05-15

While vaccination remains the most cost effective strategy for disease prevention, communicable diseases persist as the second leading cause of death worldwide. There is a need to design safe, novel vaccine delivery methods to protect against unaddressed and emerging diseases. Development of vaccines administered orally is preferable to traditional injection-based formulations for numerous reasons including improved safety and compliance, and easier manufacturing and administration. Additionally, the oral route enables stimulation of humoral and cellular immune responses at both systemic and mucosal sites to establish broader and long-lasting protection. However, oral delivery is challenging, requiring formulations to overcome the harsh gastrointestinal (GI) environment and avoid tolerance induction to achieve effective protection. Here we address the rationale for oral vaccines, including key biological and physicochemical considerations for next-generation oral vaccine design. Copyright © 2017 Elsevier B.V. All rights reserved.

Rotavirus vaccines: an overview.

OpenAIRE

Midthun, K; Kapikian, A Z

1996-01-01

Rotavirus vaccine development has focused on the delivery of live attenuated rotavirus strains by the oral route. The initial "Jennerian" approach involving bovine (RIT4237, WC3) or rhesus (RRV) rotavirus vaccine candidates showed that these vaccines were safe, well tolerated, and immunogenic but induced highly variable rates of protection against rotavirus diarrhea. The goal of a rotavirus vaccine is to prevent severe illness that can lead to dehydration in infants and young children in both...

Yellow fever vaccination status and safety in hemodialysis patients.

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Facincani, Tila; Guimarães, Maia Nogueira Crown; De Sousa Dos Santos, Sigrid

2016-07-01

The adverse effects of yellow fever (YF) vaccine in dialysis patients are not well known. There is concern about the risks and benefits of the vaccine in immunocompromised patients living in endemic areas, particularly given the risk of resurgence of urban YF with the spread of Aedes aegypti mosquitoes. The purpose of this study was to assess the coverage and safety of YF vaccine in chronic dialysis patients. A cross-sectional study of 130 chronic dialysis patients was performed. Data were collected on clinical characteristics and YF vaccine status. Patients not vaccinated against YF or without a booster vaccination within the last 10 years were referred to receive the vaccine, and adverse effects were monitored. Previous vaccination was verified in 44 patients within the last 10 years and in 26 patients at more than 10 years ago, with no mention of adverse effects. Thirty-six patients had never been vaccinated and 24 had an unknown vaccination status. Of the total 86 patients referred for immunization, 45 actually received the YF vaccine, with 24.4% experiencing mild local adverse effects and 4.4% experiencing fever. No serious adverse effects attributable to YF vaccine were observed (anaphylaxis, neurological or viscerotropic disease). YF vaccine coverage among hemodialysis patients is low, and the vaccine appeared to be safe in this population with a small sample size. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cost-effectiveness analysis of catch-up hepatitis A vaccination among unvaccinated/partially-vaccinated children

Science.gov (United States)

Hankin-Wei, Abigail; Rein, David B.; Hernandez-Romieu, Alfonso; Kennedy, Mallory J.; Bulkow, Lisa; Rosenberg, Eli; Trigg, Monica; Nelson, Noele P.

2017-01-01

Background Since 2006, the US Centers for Disease Control and Prevention has recommended hepatitis A (HepA) vaccination routinely for children aged 12–23 months to prevent hepatitis A virus (HAV) infection. However, a substantial proportion of US children are unvaccinated and susceptible to infection. We present results of economic modeling to assess whether a one-time catch-up HepA vaccination recommendation would be cost-effective. Methods We developed a Markov model of HAV infection that followed a single cohort from birth through death (birth to age 95 years). The model compared the health and economic outcomes from catch-up vaccination interventions for children at target ages from two through 17 years vs. outcomes resulting from maintaining the current recommendation of routine vaccination at age one year with no catch-up intervention. Results Over the lifetime of the cohort, catch-up vaccination would reduce the total number of infections relative to the baseline by 741 while increasing doses of vaccine by 556,989. Catch-up vaccination would increase net costs by $10.2 million, or $2.38 per person. The incremental cost of HepA vaccine catch-up intervention at age 10 years, the midpoint of the ages modeled, was $452,239 per QALY gained. Across age-cohorts, the cost-effectiveness of catch-up vaccination is most favorable at age 12 years, resulting in an Incremental Cost-Effectiveness Ratio of $189,000 per QALY gained. Conclusions Given the low baseline of HAV disease incidence achieved by current vaccination recommendations, our economic model suggests that a catch-up vaccination recommendation would be less cost-effective than many other vaccine interventions, and that HepA catch-up vaccination would become cost effective at a threshold of $50,000 per QALY only when incidence of HAV rises about 5.0 cases per 100,000 population. PMID:27317459

Parents’ and Adolescents’ Willingness to be Vaccinated Against Serogroup B Meningococcal Disease during a Mass Vaccination in Saguenay–Lac-St-Jean (Quebec

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Eve Dubé

2015-01-01

Full Text Available A mass vaccination campaign with the 4CMenB vaccine (Bexsero®; Novartis Pharmaceutical Canada Inc was launched in a serogroup B endemic area in Quebec. A telephone survey was conducted to assess parental and adolescent opinions about the acceptability of the vaccine. Intent to receive the vaccine or vaccine receipt was reported by the majority of parents (93% and adolescents (75%. Meningitis was perceived as being a dangerous disease by the majority of parents and adolescents. The majority of respondents also considered the 4CMenB vaccine to be safe and effective. The main reason for positive vaccination intention or behaviour was self-protection, while a negative attitude toward vaccination in general was the main reason mentioned by parents who did not intend to have their child vaccinated. Adolescents mainly reported lack of interest, time or information, and low perceived susceptibility and disease severity as the main reasons for not intending to be vaccinated or not being vaccinated.

Simulation of the cost-effectiveness of malaria vaccines

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Tediosi Fabrizio

2009-06-01

Full Text Available Abstract Background A wide range of possible malaria vaccines is being considered and there is a need to identify which vaccines should be prioritized for clinical development. An important element of the information needed for this prioritization is a prediction of the cost-effectiveness of potential vaccines in the transmission settings in which they are likely to be deployed. This analysis needs to consider a range of delivery modalities to ensure that clinical development plans can be aligned with the most appropriate deployment strategies. Methods The simulations are based on a previously published individual-based stochastic model for the natural history and epidemiology of Plasmodium falciparum malaria. Three different vaccine types: pre-erythrocytic vaccines (PEV, blood stage vaccines (BSV, mosquito-stage transmission-blocking vaccines (MSTBV, and combinations of these, are considered each delivered via a range of delivery modalities (Expanded Programme of Immunization – EPI-, EPI with booster, and mass vaccination combined with EPI. The cost-effectiveness ratios presented are calculated for four health outcomes, for assumed vaccine prices of US$ 2 or US$ 10 per dose, projected over a 10-year period. Results The simulations suggest that PEV will be more cost-effective in low transmission settings, while BSV at higher transmission settings. Combinations of BSV and PEV are more efficient than PEV, especially in moderate to high transmission settings, while compared to BSV they are more cost-effective in moderate to low transmission settings. Combinations of MSTBV and PEV or PEV and BSV improve the effectiveness and the cost-effectiveness compared to PEV and BSV alone only when applied with EPI and mass vaccinations. Adding booster doses to the EPI is unlikely to be a cost-effective alternative to delivering vaccines via the EPI for any vaccine, while mass vaccination improves effectiveness, especially in low transmission settings, and is

Tetanus–diphtheria–acellular pertussis vaccination for adults: an update

Science.gov (United States)

2017-01-01

Although tetanus and diphtheria have become rare in developed countries, pertussis is still endemic in some developed countries. These are vaccine-preventable diseases and vaccination for adults is important to prevent the outbreak of disease. Strategies for tetanus, diphtheria, and pertussis vaccines vary from country to country. Each country needs to monitor consistently epidemiology of the diseases and changes vaccination policies accordingly. Recent studies showed that tetanus–diphtheria–acellular pertussis vaccine for adults is effective and safe to prevent pertussis disease in infants. However, vaccine coverage still remains low than expected and seroprevalence of protective antibodies levels for tetanus, diphtheria, and pertussis decline with aging. The importance of tetanus–diphtheria–acellular pertussis vaccine administration should be emphasized for the protection of young adult and elderly people also, not limited to children. PMID:28168170

Booster vaccination with safe, modified, live-attenuated mutants of Brucella abortus strain RB51 vaccine confers protective immunity against virulent strains of B. abortus and Brucella canis in BALB/c mice.

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Truong, Quang Lam; Cho, Youngjae; Kim, Kiju; Park, Bo-Kyoung; Hahn, Tae-Wook

2015-11-01

Brucella abortus attenuated strain RB51 vaccine (RB51) is widely used in prevention of bovine brucellosis. Although vaccination with this strain has been shown to be effective in conferring protection against bovine brucellosis, RB51 has several drawbacks, including residual virulence for animals and humans. Therefore, a safe and efficacious vaccine is needed to overcome these disadvantages. In this study, we constructed several gene deletion mutants (ΔcydC, ΔcydD and ΔpurD single mutants, and ΔcydCΔcydD and ΔcydCΔpurD double mutants) of RB51 with the aim of increasing the safety of the possible use of these mutants as vaccine candidates. The RB51ΔcydC, RB51ΔcydD, RB51ΔpurD, RB51ΔcydCΔcydD and RB51ΔcydCΔpurD mutants exhibited significant attenuation of virulence when assayed in murine macrophages in vitro or in BALB/c mice. A single intraperitoneal immunization with RB51ΔcydC, RB51ΔcydD, RB51ΔcydCΔcydD or RB51ΔcydCΔpurD mutants was rapidly cleared from mice within 3 weeks, whereas the RB51ΔpurD mutant and RB51 were detectable in spleens until 4 and 7 weeks, respectively. Vaccination with a single dose of RB51 mutants induced lower protective immunity in mice than did parental RB51. However, a booster dose of these mutants provided significant levels of protection in mice against challenge with either the virulent homologous B. abortus strain 2308 or the heterologous Brucella canis strain 26. In addition, these mutants were found to induce a mixed but T-helper-1-biased humoral and cellular immune response in immunized mice. These data suggest that immunization with a booster dose of attenuated RB51 mutants provides an attractive strategy to protect against either bovine or canine brucellosis.

Cost-effectiveness of rotavirus vaccination in Albania.

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Ahmeti, Albana; Preza, Iria; Simaku, Artan; Nelaj, Erida; Clark, Andrew David; Felix Garcia, Ana Gabriela; Lara, Carlos; Hoestlandt, Céline; Blau, Julia; Bino, Silvia

2015-05-07

Rotavirus vaccines have been introduced in several European countries but can represent a considerable cost, particularly for countries that do not qualify for any external financial support. This study aimed to evaluate the cost-effectiveness of introducing rotavirus vaccination into Albania's national immunization program and to inform national decision-making by improving national capacity to conduct economic evaluations of new vaccines. The TRIVAC model was used to assess vaccine impact and cost-effectiveness. The model estimated health and economic outcomes attributed to 10 successive vaccinated birth cohorts (2013-2022) from a government and societal perspective. Epidemiological and economic data used in the model were based on national cost studies, and surveillance data, as well as estimates from the scientific literature. Cost-effectiveness was estimated for both the monovalent (RV1) and pentavalent vaccines (RV5). A multivariate scenario analysis (SA) was performed to evaluate the uncertainty around the incremental cost-effectiveness ratios (ICERs). With 3% discounting of costs and health benefits over the period 2013-2022, rotavirus vaccination in Albania could avert 51,172 outpatient visits, 14,200 hospitalizations, 27 deaths, 950 disability-adjusted life-years (DALYs), and gain 801 life-years. When both vaccines were compared to no vaccination, the discounted cost per DALY averted was US$ 2008 for RV1 and US$ 5047 for RV5 from a government perspective. From the societal perspective the values were US$ 517 and US$ 3556, respectively. From both the perspectives, the introduction of rotavirus vaccine to the Albanian immunization schedule is either cost-effective or highly cost-effective for a range of plausible scenarios. In most scenarios, including the base-case scenario, the discounted cost per DALY averted was less than three times the gross domestic product (GDP) per capita. However, rotavirus vaccination was not cost-effective when rotavirus cases

Novel Vaccine Against Mycoplasma Hyosynoviae: The Immunogenic Effect of Iscom-Based Vaccines in Swine

DEFF Research Database (Denmark)

Lauritsen, Klara Tølbøll; Vinther Heydenreich, Annette; Riber, Ulla

Arthritis in swine is frequently caused by Mycoplasma hyosynoviae (Mhs). For the development of an effective vaccine we investigated the immunogenic effect of three vaccine preparations with the ISCOM adjuvant Posintro™ from Nordic Vaccine. A: formalin fixed whole-cells Mhs (300 µg/dose) mixed...... with Posintro, B: Deoxycholate extracted lipoproteins from Mhs organisms (DOC-antigen, 300 μg/dose) in Posintro and C: DOC-antigen (50 μg/dose) in Posintro. Each vaccine-group contained three pigs. Vaccinations (i.m.) were performed at 12 and 15 weeks of age. The development of specific IgG and secretion...... of IFNγ were measured. Three weeks after the second vaccination, pigs were euthanised and autopsied. Vaccine B induced a high level of specific serum IgG in all pigs a week after boost. Vaccine C gave a variable response after boost, with two pigs seroconverting, while no response was seen by vaccine A...

DENGUE VACCINE, CHALLENGES, DEVELOPMENT AND STRATEGIES

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Dewi Marbawati

2014-08-01

Full Text Available ABSTRAKPenyakit demam Dengue endemik di lebih dari 100 negara di dunia. Obat anti virus Dengue efektif belum ditemukan danpengendalian vektor dinilai kurang efektif, sehingga diperlukan upaya pencegahan dengan vaksinasi. Vaksin Dengue yangideal adalah murah, mencakup 4 serotipe, efektif dalam memberikan kekebalan, cukup diberikan sekali seumur hidup, aman,memberi kekebalan jangka panjang, stabil dalam penyimpanan dan stabil secara genetis (tidak bermutasi. Beberapakandidat vaksin yang telah dan sedang dikembangkan oleh para peneliti di seluruh dunia adalah tetravalent live attenuatedvaccine, vaksin Chimera (ChimeriVax, vaksin subunit dan vaksin DNA. Vaksin Dengue dipandang sebagai pendekatan yangefektif dan berkesinambungan dalam mengendalikan penyakit Dengue. Tahun 2003 telah terbentuk Pediatric DengueVaccine Initiative (PDVI, yaitu sebuah konsorsium internasional yang bergerak dalam advokasi untuk meyakinkanmasyarakat internasional akan penting dan mendesaknya vaksin Dengue. Konsorsium vaksin Dengue Indonesia saat iniberupaya mengembangkan vaksin Dengue dengan menggunakan strain virus lokal.Kata kunci: Dengue, virus, vaksinABSTRACTDengue fever is endemic in more than 100 countries in the world. The effective dengue antiviral drug has not been found yet,and vector control is considered less effective. Prevention program by vaccination is needed. An ideal dengue vaccine shouldbe inexpensive, covering four serotypes (tetravalent, effective in providing immunity, given once a lifetime, safe, stable instorage and genetically. Several vaccine candidates have been and are being developed included attenuated tetravalentvaccine, ChimeriVax, sub- unit vaccines and DNA vaccines. Dengue vaccine is seen as an effective and sustainable approachto controll Dengue infection. In 2003, Pediatric Dengue Vaccine Initiative (PDVI has been formed as an internationalconsortium involved in advocacy to convince the international community about the essence and urgency

An Approach to Identify and Characterize a Subunit Candidate Shigella Vaccine Antigen.

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Pore, Debasis; Chakrabarti, Manoj K

2016-01-01

Shigellosis remains a serious issue throughout the developing countries, particularly in children under the age of 5. Numerous strategies have been tested to develop vaccines targeting shigellosis; unfortunately despite several years of extensive research, no safe, effective, and inexpensive vaccine against shigellosis is available so far. Here, we illustrate in detail an approach to identify and establish immunogenic outer membrane proteins from Shigella flexneri 2a as subunit vaccine candidates.

Evaluation of immune response to hepatitis A vaccination and vaccine safety in juvenile idiopathic arthritis

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Muferet Erguven

2011-05-01

Conclusion: Hepatitis A vaccine was safe in patients with JIA, and response to vaccine did not differ between healthy children and patients with JIA except for children with active systemic JIA receiving anti-tumor necrosis factor alpha drugs.

Bioengineering towards self-assembly of particulate vaccines.

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Rehm, Bernd H A

2017-12-01

There is an unmet demand for safe and efficient vaccines for prevention of various infectious diseases. Subunit vaccines comprise selected pathogen specific antigens are a safe alternative to whole organism vaccines. However they often lack immunogenicity. Natural and synthetic self-assembling polymers and proteins will be reviewed in view their use to encapsulate and/or display antigens to serve as immunogenic antigen carriers for induction of protective immunity. Recent advances made in in vivo assembly of antigen-displaying polyester inclusions will be a focus. Particulate vaccines are inherently immunogenic due to enhanced uptake by antigen presenting cells which process antigens mediating adaptive immune responses. Bioengineering approaches enable the design of tailor-made particulate vaccines to fine tune immune responses towards protective immunity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Killed oral cholera vaccines: history, development and implementation challenges.

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Lopez, Anna Lena; Gonzales, Maria Liza Antoinette; Aldaba, Josephine G; Nair, G Balakrish

2014-09-01

Cholera is still a major global health problem, affecting mainly people living in unsanitary conditions and who are at risk for outbreaks of cholera. During the past decade, outbreaks are increasingly reported from more countries. From the early killed oral cholera vaccine, rapid improvements in vaccine development occurred as a result of a better understanding of the epidemiology of the disease, pathogenesis of cholera infection and immunity. The newer-generation oral killed cholera vaccines have been shown to be safe and effective in field trials conducted in cholera endemic areas. Likewise, they have been shown to be protective when used during outbreak settings. Aside from providing direct protection to vaccinated individuals, recent studies have demonstrated that these killed oral vaccines also confer indirect protection through herd immunity. Although new-generation oral cholera vaccines should not be considered in isolation from other preventive approaches in countries where they are most needed, especially improved water quality and sanitation, these vaccines serve as immediately available public health tools for preventing further morbidity and mortality from cholera. However, despite its availability for more than two decades, use of these vaccines has not been optimized. Although there are limitations of the currently available oral cholera vaccines, recent data show that the vaccines are safe, feasible to use even in difficult circumstances and able to provide protection in various settings. Clear identification of the areas and target population groups who will benefit from the use of the cholera vaccines will be required and strategies to facilitate accessibility and usage of these vaccines in these areas and population groups will need to be developed.

Cost-effectiveness of rotavirus vaccination in Turkey

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Tulin Koksal

2017-10-01

Conclusion: At a cost per vaccine course of US$31.5 for monovalent and US$38 for pentavalent vaccine, routine RV vaccination could be potentially cost effective and also cost saving in Turkey. National RV vaccinations will play a significant role in preventing RV infections.

Vaccination of dogs with six different candidate leishmaniasis vaccines composed of a chimerical recombinant protein containing ribosomal and histone protein epitopes in combination with different adjuvants.

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Poot, J; Janssen, L H M; van Kasteren-Westerneng, T J; van der Heijden-Liefkens, K H A; Schijns, V E J C; Heckeroth, A

2009-07-16

Chimerical protein "Q", composed of antigenic ribosomal and histone sequences, in combination with live BCG is a promising canine leishmaniasis vaccine candidate; one of the few vaccine candidates that have been tested successfully in dogs. Unfortunately, live BCG is not an appropriate adjuvant for commercial application due to safety problems in dogs. In order to find a safe adjuvant with similar efficacy to live BCG, muramyl dipeptide, aluminium hydroxide, Matrix C and killed Propionibacterium acnes in combination with either E. coli- or baculovirus-produced recombinant JPCM5_Q protein were tested. Groups of five or seven dogs were vaccinated with six different adjuvant-antigen combinations and challenged with a high dose intravenous injection of Leishmania infantum JPC strain promastigotes. All candidate vaccines proved to be safe, and both humoral and cellular responses to the recombinant proteins were detected at the end of the prime-boost vaccination scheme. However, clinical and parasitological data obtained during the 10 month follow-up period indicated that protection was not induced by either of the six candidate vaccines. Although no direct evidence was obtained, our data suggest that live BCG may have a significant protective effect against challenge with L. infantum in dogs.

Cost-effectiveness of hepatitis A vaccination in Indonesia

Science.gov (United States)

Suwantika, Auliya A; Beutels, Philippe; Postma, Maarten J

2014-01-01

Objective This study aims to assess the cost-effectiveness of hepatitis A immunization in Indonesia, including an explicit comparison between one-dose and two-dose vaccines. Methods An age-structured cohort model based on a decision tree was developed for the 2012 Indonesia birth cohort. Using the model, we made a comparison on the use of two-dose and one-dose vaccines. The model involved a 70-year time horizon with 1-month cycles for children less than 2 years old and annually thereafter. Monte Carlo simulations were used to examine the economic acceptability and affordability of the hepatitis A vaccination. Results Vaccination would save US$ 3 795 148 and US$ 2 892 920 from the societal perspective, for the two-dose and one-dose vaccine schedules, respectively, in the context of hepatitis A treatment. It also would save 8917 and 6614 discounted quality-adjusted-life-years (QALYs), respectively. With the vaccine price of US$ 3.21 per dose, the implementation of single dose vaccine would yield an incremental cost-effectiveness ratio (ICER) of US$ 4933 per QALY gained versus no vaccination, whereas the two-dose versus one-dose schedule would cost US$ 14 568 per QALY gained. Considering the 2012 gross-domestic-product (GDP) per capita in Indonesia of US$ 3557, the results indicate that hepatitis A vaccination would be a cost-effective intervention, both for the two-dose and one-dose vaccine schedules in isolation, but two-dose vaccination would no longer be cost-effective if one-dose vaccination is a feasible option. Vaccination would be 100% affordable at budgets of US$ 71 408 000 and US$ 37 690 000 for the implementation of the two-dose and one-dose vaccine schedules, respectively. Conclusions The implementation of hepatitis A vaccination in Indonesia would be a cost-effective health intervention under the market vaccine price. Given the budget limitations, the use of a one-dose-vaccine schedule would be more realistic to be applied than a two

Chikungunya Virus Vaccines: Viral Vector-Based Approaches.

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Ramsauer, Katrin; Tangy, Frédéric

2016-12-15

In 2013, a major chikungunya virus (CHIKV) epidemic reached the Americas. In the past 2 years, >1.7 million people have been infected. In light of the current epidemic, with millions of people in North and South America at risk, efforts to rapidly develop effective vaccines have increased. Here, we focus on CHIKV vaccines that use viral-vector technologies. This group of vaccine candidates shares an ability to potently induce humoral and cellular immune responses by use of highly attenuated and safe vaccine backbones. So far, well-described vectors such as modified vaccinia virus Ankara, complex adenovirus, vesicular stomatitis virus, alphavirus-based chimeras, and measles vaccine Schwarz strain (MV/Schw) have been described as potential vaccines. We summarize here the recent data on these experimental vaccines, with a focus on the preclinical and clinical activities on the MV/Schw-based candidate, which is the first CHIKV-vectored vaccine that has completed a clinical trial. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Estimating population effects of vaccination using large, routinely collected data.

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Halloran, M Elizabeth; Hudgens, Michael G

2018-01-30

Vaccination in populations can have several kinds of effects. Establishing that vaccination produces population-level effects beyond the direct effects in the vaccinated individuals can have important consequences for public health policy. Formal methods have been developed for study designs and analysis that can estimate the different effects of vaccination. However, implementing field studies to evaluate the different effects of vaccination can be expensive, of limited generalizability, or unethical. It would be advantageous to use routinely collected data to estimate the different effects of vaccination. We consider how different types of data are needed to estimate different effects of vaccination. The examples include rotavirus vaccination of young children, influenza vaccination of elderly adults, and a targeted influenza vaccination campaign in schools. Directions for future research are discussed. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Clinical effectiveness and cost effect analysis of quadrivalent HPV vaccine

OpenAIRE

Lekić, Nataša

2008-01-01

1 ABSTRACT Quadrivalent Human Papillomavirus Vaccine- Evaluation of clinical effectiveness and national vaccine programs Author: Nataša Lekić Research Advisor: PharmDr. Lenka Práznovcová, Ph.D. Department of Social and Clinical Pharmacy, Faculty of Pharmacy in Hradec Králové, Charles University in Prague. SUMMARY QUADRIVALENT HPV VACCINE- EVALUATION OF CLINICAL EFFECTIVENESS AND NATIONAL VACCINE PROGRAMS Background: Human papillomavirus types 6, 11,16 and 18 cause majority of genital warts an...

Cost-effectiveness of pneumococcal conjugate vaccination in Croatia.

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Vučina, V Višekruna; Filipović, S Kurečić; Kožnjak, N; Stamenić, V; Clark, A D; Mounaud, B; Blau, J; Hoestlandt, C; Kaić, B

2015-05-07

Pneumococcus is a known cause of meningitis, pneumonia, sepsis, and acute otitis media in children and adults globally. Two new vaccines for children have the potential to prevent illness, disability, and death, but these vaccines are expensive. The Croatian Ministry of Health has considered introducing the vaccine in the past, but requires economic evidence to ensure that the limited funds available for health care will be used in the most effective way. Croatia appointed a multidisciplinary team of experts to evaluate the cost-effectiveness of introducing pneumococcal conjugate vaccination (PCV) into the national routine child immunization program. Both 10-valent and 13-valent PCV (PCV10 and PCV13) were compared to a scenario assuming no vaccination. The TRIVAC decision-support model was used to estimate cost-effectiveness over the period 2014-2033. We used national evidence on demographics, pneumococcal disease incidence and mortality, the age distribution of disease in children, health service utilization, vaccine coverage, vaccine timeliness, and serotype coverage. Vaccine effectiveness was based on evidence from the scientific literature. Detailed health care costs were not available from the Croatian Institute for Health Insurance at the time of the analysis so assumptions and World Health Organization (WHO) estimates for Croatia were used. We assumed a three-dose primary vaccination schedule, and an initial price of US$ 30 per dose for PCV10 and US$ 35 per dose for PCV13. We ran univariate sensitivity analyses and multivariate scenario analyses. Either vaccine is estimated to prevent approximately 100 hospital admissions and one death each year in children younger than five in Croatia. Compared to no vaccine, the discounted cost-effectiveness of either vaccine is estimated to be around US$ 69,000-77,000 per disability-adjusted life-years (DALYs) averted over the period 2014-2033 (from the government or societal perspective). Only two alternative scenarios

Evolution of rational vaccine designs for genital herpes immunotherapy.

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Kaufmann, Johanna Katharina; Flechtner, Jessica Baker

2016-04-01

Immunotherapeutic vaccines have emerged as a novel treatment modality for genital herpes, a sexually transmitted disease mainly caused by herpes simplex virus type 2. The approaches to identify potential vaccine antigens have evolved from classic virus attenuation and characterization of antibody and T cell responses in exposed, but seronegative individuals, to systematic screens for novel T cell antigens. Combined with implementation of novel vaccine concepts revolving around immune evasion and local recruitment of immune effectors, the development of a safe and effective therapeutic vaccine is within reach. Here, we describe the vaccine approaches that currently show promise at clinical and pre-clinical stages and link them to the evolving scientific strategies that led to their identification. Copyright © 2016 Elsevier B.V. All rights reserved.

Cost-effectiveness analysis of rotavirus vaccination in Argentina.

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Urueña, Analía; Pippo, Tomás; Betelu, María Sol; Virgilio, Federico; Hernández, Laura; Giglio, Norberto; Gentile, Ángela; Diosque, Máximo; Vizzotti, Carla

2015-05-07

Rotavirus is a leading cause of severe diarrhea in children under 5. In Argentina, the most affected regions are the Northeast and Northwest, where hospitalizations and deaths are more frequent. This study estimated the cost-effectiveness of adding either of the two licensed rotavirus vaccines to the routine immunization schedule. The integrated TRIVAC vaccine cost-effectiveness model from the Pan American Health Organization's ProVac Initiative (Version 2.0) was used to assess health benefits, costs savings, life-years gained (LYGs), DALYs averted, and cost/DALY averted of vaccinating 10 successive cohorts, from the health care system and societal perspectives. Two doses of monovalent (RV1) rotavirus vaccine and three doses of pentavalent (RV5) rotavirus vaccine were each compared to a scenario assuming no vaccination. The price/dose was US$ 7.50 and US$ 5.15 for RV1 and RV5, respectively. We ran both a national and sub-national analysis, discounting all costs and benefits 3% annually. Our base case results were compared to a range of alternative univariate and multivariate scenarios. The number of LYGs was 5962 and 6440 for RV1 and RV5, respectively. The cost/DALY averted when compared to no vaccination from the health care system and societal perspective was: US$ 3870 and US$ 1802 for RV1, and US$ 2414 and US$ 358 for RV5, respectively. Equivalent figures for the Northeast were US$ 1470 and US$ 636 for RV1, and US$ 913 and US$ 80 for RV5. Therefore, rotavirus vaccination was more cost-effective in the Northeast compared to the whole country; and, in the Northwest, health service's costs saved outweighed the cost of introducing the vaccine. Vaccination with either vaccine compared to no vaccination was highly cost-effective based on WHO guidelines and Argentina's 2011 per capita GDP of US$ 9090. Key variables influencing results were vaccine efficacy, annual loss of efficacy, relative coverage of deaths, vaccine price, and discount rate. Compared to no

Cost-effectiveness of Rotavirus vaccination in Vietnam

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Goldie Sue J

2009-01-01

Full Text Available Abstract Background Rotavirus is the most common cause of severe diarrhea leading to hospitalization or disease-specific death among young children. New rotavirus vaccines have recently been approved. Some previous studies have provided broad qualitative insights into the health and economic consequences of introducing the vaccines into low-income countries, representing several features of rotavirus infection, such as varying degrees of severity and age-dependency of clinical manifestation, in their model-based analyses. We extend this work to reflect additional features of rotavirus (e.g., the possibility of reinfection and varying degrees of partial immunity conferred by natural infection, and assess the influence of the features on the cost-effectiveness of rotavirus vaccination. Methods We developed a Markov model that reflects key features of rotavirus infection, using the most recent data available. We applied the model to the 2004 Vietnamese birth cohort and re-evaluated the cost-effectiveness (2004 US dollars per disability-adjusted life year [DALY] of rotavirus vaccination (Rotarix® compared to no vaccination, from both societal and health care system perspectives. We conducted univariate sensitivity analyses and also performed a probabilistic sensitivity analysis, based on Monte Carlo simulations drawing parameter values from the distributions assigned to key uncertain parameters. Results Rotavirus vaccination would not completely protect young children against rotavirus infection due to the partial nature of vaccine immunity, but would effectively reduce severe cases of rotavirus gastroenteritis (outpatient visits, hospitalizations, or deaths by about 67% over the first 5 years of life. Under base-case assumptions (94% coverage and $5 per dose, the incremental cost per DALY averted from vaccination compared to no vaccination would be $540 from the societal perspective and $550 from the health care system perspective. Conclusion

Efficacy of recombinant birch pollen vaccine for the treatment of birch-allergic rhinoconjunctivitis

DEFF Research Database (Denmark)

Pauli, Gabrielle; Larsen, Tina H; Rak, Sabina

2008-01-01

BACKGROUND: Recombinant DNA technology has the potential to produce allergen-specific immunotherapy vaccines with defined composition. OBJECTIVE: To evaluate the effectiveness of a new recombinant birch pollen allergen vaccine in patients with birch pollen allergy. METHODS: A multicenter, randomi......-treated group. CONCLUSION: The rBet v 1-based vaccine was safe and effective in treating birch pollen allergy, and induced a highly specific immune response.......BACKGROUND: Recombinant DNA technology has the potential to produce allergen-specific immunotherapy vaccines with defined composition. OBJECTIVE: To evaluate the effectiveness of a new recombinant birch pollen allergen vaccine in patients with birch pollen allergy. METHODS: A multicenter......, randomized, double-blind, placebo-controlled trial was undertaken to compare the following 3 vaccines in 134 adults with birch pollen allergy: recombinant birch pollen allergen vaccine (rBet v 1a), licensed birch pollen extract, natural purified birch pollen allergen (nBet v 1), and placebo. Patients...

Rotavirus vaccine strain transmission by vaccinated infants in the foster home.

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Miura, Hiroki; Kawamura, Yoshiki; Sugata, Ken; Koshiyama, Nozomi; Yoshikawa, Akiko; Komoto, Satoshi; Taniguchi, Koki; Ihira, Masaru; Yoshikawa, Tetsushi

2017-01-01

Previous studies have demonstrated the transmission of rotavirus vaccine strains from vaccinated children to nonvaccinated siblings. We sought to fully elucidate the safety of rotavirus (RV) vaccination in closed contact circumstance, such as the foster home for future assessment of the vaccine safety in an neonatal intensive care unit. Stool samples were collected from 4 RV vaccinated (160 samples) and 23 unvaccinated (766 samples) infants. RV viral RNA loads were measured using real-time reverse transcription polymerase chain reaction (RT-PCR). RV vaccine strain RNA was persistently detected in stool samples collected from the four vaccine recipients and one unvaccinated infant, but not in the stool samples collected from the 22 other unvaccinated infants. The unvaccinated infant who tested positive for the RV vaccine strain was vaccinated prior to enrollment in this study. The quantitative real-time RT-PCR data revealed a peak viral RNA load 1 week after vaccination followed by a gradual decrease. The current study suggests that RV vaccination may be safe in a close contact environment because there was limited transmission from RV vaccinated to unvaccinated infants. J. Med. Virol. 89:79-84, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Adenovirus-Vectored Vaccine as a Rapid-Response Tool Against Avian Influenza Pandemic

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Van Kampen, K. R.; Tang, D. C.

2007-01-01

Influenza viruses in nature undergo genetic mutation and reassortment. Three pandemics of avian influenza in man were recorded in the twentieth century. Highly pathogenic avian influenza (HPAI) viruses currently in circulation pose a threat for another world-wide pandemic, if they become transmissible from man to man. Manufacturing protective vaccines using current egg-based technology is often difficult due to the virulence of the virus and its adverse effects on the embryonating egg substrate. New technologies allow the creation of safe and protective pandemic influenza vaccines without the need for egg based substrates. These technologies allow new vaccines to be created in less than one month. Manufacturing is in tissue culture, not eggs. Vaccine can be administered to man non-invasively, without adjuvants, eliciting a rapid and protective immune response. Protective immunity against avian influenza (AI) virus was elicited in chickens by single-dose in ovo vaccination with a replication-competent adenovirus (RCA)-free human adenovirus serotype 5 (Ad5)-derived vector encoding an H5N9 avian influenza virus hemagglutinin. Vaccinated chickens were protected against both H5N1 and H5N2 HPAI virus challenges. Mass-administration of this bird flu vaccine can be streamlined with available robotic in ovo injectors. Vaccination using this vaccine could protect the the largest host reservoir (chickens) and greatly reduce the exposure of man to avian influenza. In addition, Ad5-vectored vaccines can be produced rapidly and the safety margin of a non-replicating vector is superior to that of a replicating counterpart. Furthermore, this mode of vaccination is compatible with epidemiological surveys of natural AI virus infections. In addition to mass immunization of poultry, both animals and humans have been effectively immunized by intranasal administration of Ad5-vectored influenza vaccines without any appreciable side effects, even in mice and human volunteers with

Third generation DIVA vaccine towards classical swine fever virus. Efficacy in face of maternal immunity

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Rangelova, Desislava Yordanova

General purpose and objectives Classical swine fever (CSF) is a highly contagious disease that causes huge economical losses and animal welfare concerns worldwide. Generally, vaccination is an effective and safe method to control the disease. Following vaccination the pig’s immune system develops...... a new DIVA vaccine candidate. The vaccine candidate “CP7E2alf” is intended for either intramuscular vaccination of domestic pig or for bait vaccination of wild boar. In this thesis as part of the clinical testing of the injection vaccine the efficacy of “CP7E2alf” was evaluated in young piglets...

Development of a chimeric Zika vaccine using a licensed live-attenuated flavivirus vaccine as backbone.

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Li, Xiao-Feng; Dong, Hao-Long; Wang, Hong-Jiang; Huang, Xing-Yao; Qiu, Ye-Feng; Ji, Xue; Ye, Qing; Li, Chunfeng; Liu, Yang; Deng, Yong-Qiang; Jiang, Tao; Cheng, Gong; Zhang, Fu-Chun; Davidson, Andrew D; Song, Ya-Jun; Shi, Pei-Yong; Qin, Cheng-Feng

2018-02-14

The global spread of Zika virus (ZIKV) and its unexpected association with congenital defects necessitates the rapid development of a safe and effective vaccine. Here we report the development and characterization of a recombinant chimeric ZIKV vaccine candidate (termed ChinZIKV) that expresses the prM-E proteins of ZIKV using the licensed Japanese encephalitis live-attenuated vaccine SA14-14-2 as the genetic backbone. ChinZIKV retains its replication activity and genetic stability in vitro, while exhibiting an attenuation phenotype in multiple animal models. Remarkably, immunization of mice and rhesus macaques with a single dose of ChinZIKV elicits robust and long-lasting immune responses, and confers complete protection against ZIKV challenge. Significantly, female mice immunized with ChinZIKV are protected against placental and fetal damage upon ZIKV challenge during pregnancy. Overall, our study provides an alternative vaccine platform in response to the ZIKV emergency, and the safety, immunogenicity, and protection profiles of ChinZIKV warrant further clinical development.

Vaccine hesitancy and trust. Ethical aspects of risk communication.

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Nihlén Fahlquist, Jessica

2018-03-01

This paper analyses vaccination policy from an ethical perspective, against the background of the growing hesitancy towards e.g. the measles vaccine. The paper is normative and analyses ethical aspects of risk communication in the context of vaccination. It is argued that ethical analysis of risk communication should be done at the level of the message, the procedure and the effects. The paper takes examples from the Swedish context, linking the current lack of trust in experts to the 2009 vaccination policy and communication promoting the H1N1 vaccine Pandemrix. During the Swedish H1N1 vaccination policy in 2009, the message was that the vaccine is safe. However, a group of adolescents developed narcolepsy as a side effect of the vaccine. Taking this into account, it becomes clear that the government should communicate risks and benefits responsibly and take responsibility for individuals affected negatively by populational health interventions. To communicate respectfully entails not treating vaccine sceptics as ill-informed or less educated, but instead taking the concerns of the vaccine hesitant, who potentially could change their minds, as a starting-point of a respectful discussion. There will inevitably be individuals who suffer from side effects of justifiable population-based health promotion activities. However, the public should be able to trust the message and count on the government to take responsibility for individuals affected by side effects. This is important for normative reasons, but is additionally likely to contribute to restored and maintained trust.

Balancing evidence and uncertainty when considering rubella vaccine introduction.

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Justin Lessler

Full Text Available Despite a safe and effective vaccine, rubella vaccination programs with inadequate coverage can raise the average age of rubella infection; thereby increasing rubella cases among pregnant women and the resulting congenital rubella syndrome (CRS in their newborns. The vaccination coverage necessary to reduce CRS depends on the birthrate in a country and the reproductive number, R0, a measure of how efficiently a disease transmits. While the birthrate within a country can be known with some accuracy, R0 varies between settings and can be difficult to measure. Here we aim to provide guidance on the safe introduction of rubella vaccine into countries in the face of substantial uncertainty in R0.We estimated the distribution of R0 in African countries based on the age distribution of rubella infection using Bayesian hierarchical models. We developed an age specific model of rubella transmission to predict the level of R0 that would result in an increase in CRS burden for specific birth rates and coverage levels. Combining these results, we summarize the safety of introducing rubella vaccine across demographic and coverage contexts.The median R0 of rubella in the African region is 5.2, with 90% of countries expected to have an R0 between 4.0 and 6.7. Overall, we predict that countries maintaining routine vaccination coverage of 80% or higher are can be confident in seeing a reduction in CRS over a 30 year time horizon.Under realistic assumptions about human contact, our results suggest that even in low birth rate settings high vaccine coverage must be maintained to avoid an increase in CRS. These results lend further support to the WHO recommendation that countries reach 80% coverage for measles vaccine before introducing rubella vaccination, and highlight the importance of maintaining high levels of vaccination coverage once the vaccine is introduced.

Balancing evidence and uncertainty when considering rubella vaccine introduction.

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Lessler, Justin; Metcalf, C Jessica E

2013-01-01

Despite a safe and effective vaccine, rubella vaccination programs with inadequate coverage can raise the average age of rubella infection; thereby increasing rubella cases among pregnant women and the resulting congenital rubella syndrome (CRS) in their newborns. The vaccination coverage necessary to reduce CRS depends on the birthrate in a country and the reproductive number, R0, a measure of how efficiently a disease transmits. While the birthrate within a country can be known with some accuracy, R0 varies between settings and can be difficult to measure. Here we aim to provide guidance on the safe introduction of rubella vaccine into countries in the face of substantial uncertainty in R0. We estimated the distribution of R0 in African countries based on the age distribution of rubella infection using Bayesian hierarchical models. We developed an age specific model of rubella transmission to predict the level of R0 that would result in an increase in CRS burden for specific birth rates and coverage levels. Combining these results, we summarize the safety of introducing rubella vaccine across demographic and coverage contexts. The median R0 of rubella in the African region is 5.2, with 90% of countries expected to have an R0 between 4.0 and 6.7. Overall, we predict that countries maintaining routine vaccination coverage of 80% or higher are can be confident in seeing a reduction in CRS over a 30 year time horizon. Under realistic assumptions about human contact, our results suggest that even in low birth rate settings high vaccine coverage must be maintained to avoid an increase in CRS. These results lend further support to the WHO recommendation that countries reach 80% coverage for measles vaccine before introducing rubella vaccination, and highlight the importance of maintaining high levels of vaccination coverage once the vaccine is introduced.

The effect of current Schistosoma mansoni infection on the immunogenicity of a candidate TB vaccine, MVA85A, in BCG-vaccinated adolescents: An open-label trial.

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Anne Wajja

2017-05-01

Full Text Available Helminth infection may affect vaccine immunogenicity and efficacy. Adolescents, a target population for tuberculosis booster vaccines, often have a high helminth burden. We investigated effects of Schistosoma mansoni (Sm on the immunogenicity and safety of MVA85A, a model candidate tuberculosis vaccine, in BCG-vaccinated Ugandan adolescents.In this phase II open label trial we enrolled 36 healthy, previously BCG-vaccinated adolescents, 18 with no helminth infection detected, 18 with Sm only. The primary outcome was immunogenicity measured by Ag85A-specific interferon gamma ELISpot assay. Tuberculosis and schistosome-specific responses were also assessed by whole-blood stimulation and multiplex cytokine assay, and by antibody ELISAs.Ag85A-specific cellular responses increased significantly following immunisation but with no differences between the two groups. Sm infection was associated with higher pre-immunisation Ag85A-specific IgG4 but with no change in antibody levels following immunisation. There were no serious adverse events. Most reactogenicity events were of mild or moderate severity and resolved quickly.The significant Ag85A-specific T cell responses and lack of difference between Sm-infected and uninfected participants is encouraging for tuberculosis vaccine development. The implications of pre-existing Ag85A-specific IgG4 antibodies for protective immunity against tuberculosis among those infected with Sm are not known. MVA85A was safe in this population.ClinicalTrials.gov NCT02178748.

Safety and Efficacy Profile of Commercial Veterinary Vaccines against Rift Valley Fever: A Review Study

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Moataz Alhaj

2016-01-01

Full Text Available Rift Valley Fever (RVF is an infectious illness with serious clinical manifestations and health consequences in humans as well as a wide range of domestic ruminants. This review provides significant information about the prevention options of RVF along with the safety-efficacy profile of commercial vaccines and some of RVF vaccination strategies. Information presented in this paper was obtained through a systematic investigation of published data about RVF vaccines. Like other viral diseases, the prevention of RVF relies heavily on immunization of susceptible herds with safe and cost-effective vaccine that is able to confer long-term protective immunity. Several strains of RVF vaccines have been developed and are available in commercial production including Formalin-Inactivated vaccine, live attenuated Smithburn vaccine, and the most recent Clone13. Although Formalin-Inactivated vaccine and live attenuated Smithburn vaccine are immunogenic and widely used in prevention programs, they proved to be accompanied by significant concerns. Despite Clone13 vaccine being suggested as safe in pregnant ewes and as highly immunogenic along with its potential for differentiating infected from vaccinated animals (DIVA, a recent study raised concerns about the safety of the vaccine during the first trimester of gestation. Accordingly, RVF vaccines that are currently available in the market to a significant extent do not fulfill the requirements of safety, potency, and DIVA. These adverse effects stressed the need for developing new vaccines with an excellent safety profile to bridge the gap in safety and immunity. Bringing RVF vaccine candidates to local markets besides the absence of validated serological test for DIVA remain the major challenges of RVF control.

Expected epidemiological impact of the introduction of a partially effective HIV vaccine among men who have sex with men in Australia.

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Gray, Richard T; Ghaus, Mohammad H; Hoare, Alexander; Wilson, David P

2011-08-18

A trial of the ALVAC-AIDSVAX HIV vaccine was recently found to be partially effective in preventing HIV transmission among study participants in Thailand. The success of this trial means that vaccination may become a viable intervention for the prevention of HIV infection in the medium-term future. Assuming that the vaccine has similar relative protective effectiveness per exposure event for reducing transmission among men who have sex with men (MSM) in high-income settings we investigated the potential population-level impact of rolling out such a vaccine among MSM in New South Wales, Australia. Using a detailed individual-based transmission model that simulates a population of sexually active MSM it was found that one-off intervention of 60% or 30% coverage of a vaccine with characteristics like the ALVAX-AIDSVAX vaccine would likely reduce the cumulative incidence of HIV by 9.6% and 5.1%, respectively, over a 10-year period. Due to the waning of vaccine efficacy, a booster vaccination could be required to maintain this reduction in incidence over the long term. If the previously vaccinated population is given a booster vaccine, with the same protection conferred as with the initial vaccination, every 5 years or every 2 years then the cumulative incidence over 10 years for 60% coverage could be reduced by 14.4% and 22.8%, respectively. Such a weak vaccine, with boosting, may be a potential intervention strategy for the prevention of HIV infection in MSM in high-income countries if further trials show boosting to be safe, acceptable, and cost-effective. However, the moderately low population-level impact suggests that a public health strategy involving such a vaccine should be supplemented with other biomedical and educational strategies. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Vaccines in Development against West Nile Virus

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Frederic Tangy

2013-09-01

Full Text Available West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine.

Safety of human papillomavirus vaccines: a review.

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Stillo, Michela; Carrillo Santisteve, Paloma; Lopalco, Pier Luigi

2015-05-01

Between 2006 and 2009, two different human papillomavirus virus (HPV) vaccines were licensed for use: a quadrivalent (qHPVv) and a bivalent (bHPVv) vaccine. Since 2008, HPV vaccination programmes have been implemented in the majority of the industrialized countries. Since 2013, HPV vaccination has been part of the national programs of 66 countries including almost all countries in North America and Western Europe. Despite all the efforts made by individual countries, coverage rates are lower than expected. Vaccine safety represents one of the main concerns associated with the lack of acceptance of HPV vaccination both in the European Union/European Economic Area and elsewhere. Safety data published on bivalent and quadrivalent HPV vaccines, both in pre-licensure and post-licensure phase, are reviewed. Based on the latest scientific evidence, both HPV vaccines seem to be safe. Nevertheless, public concern and rumors about adverse events (AE) represent an important barrier to overcome in order to increase vaccine coverage. Passive surveillance of AEs is an important tool for detecting safety signals, but it should be complemented by activities aimed at assessing the real cause of all suspect AEs. Improved vaccine safety surveillance is the first step for effective communication based on scientific evidence.

2009 H1N1 Flu Vaccine Facts

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... of this page please turn Javascript on. Feature: Flu 2009 H1N1 Flu Vaccine Facts Past Issues / Fall 2009 Table of ... the H1N1 flu vaccine. 1 The 2009 H1N1 flu vaccine is safe and well tested. Clinical trials ...

Antibody Persistence in Adults Two Years after Vaccination with an H1N1 2009 Pandemic Influenza Virus-Like Particle Vaccine.

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Nuriban Valero-Pacheco

Full Text Available The influenza virus is a human pathogen that causes epidemics every year, as well as potential pandemic outbreaks, as occurred in 2009. Vaccination has proven to be sufficient in the prevention and containment of viral spreading. In addition to the current egg-based vaccines, new and promising vaccine platforms, such as cell culture-derived vaccines that include virus-like particles (VLPs, have been developed. VLPs have been shown to be both safe and immunogenic against influenza infections. Although antibody persistence has been studied in traditional egg-based influenza vaccines, studies on antibody response durations induced by VLP influenza vaccines in humans are scarce. Here, we show that subjects vaccinated with an insect cell-derived VLP vaccine, in the midst of the 2009 H1N1 influenza pandemic outbreak in Mexico City, showed antibody persistence up to 24 months post-vaccination. Additionally, we found that subjects that reported being revaccinated with a subsequent inactivated influenza virus vaccine showed higher antibody titres to the pandemic influenza virus than those who were not revaccinated. These findings provide insights into the duration of the antibody responses elicited by an insect cell-derived pandemic influenza VLP vaccine and the possible effects of subsequent influenza vaccination on antibody persistence induced by this VLP vaccine in humans.

Impact of vaccine herd-protection effects in cost-effectiveness analyses of childhood vaccinations. A quantitative comparative analysis.

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Holubar, Marisa; Stavroulakis, Maria Christina; Maldonado, Yvonne; Ioannidis, John P A; Contopoulos-Ioannidis, Despina

2017-01-01

Inclusion of vaccine herd-protection effects in cost-effectiveness analyses (CEAs) can impact the CEAs-conclusions. However, empirical epidemiologic data on the size of herd-protection effects from original studies are limited. We performed a quantitative comparative analysis of the impact of herd-protection effects in CEAs for four childhood vaccinations (pneumococcal, meningococcal, rotavirus and influenza). We considered CEAs reporting incremental-cost-effectiveness-ratios (ICERs) (per quality-adjusted-life-years [QALY] gained; per life-years [LY] gained or per disability-adjusted-life-years [DALY] avoided), both with and without herd protection, while keeping all other model parameters stable. We calculated the size of the ICER-differences without vs with-herd-protection and estimated how often inclusion of herd-protection led to crossing of the cost-effectiveness threshold (of an assumed societal-willingness-to-pay) of $50,000 for more-developed countries or X3GDP/capita (WHO-threshold) for less-developed countries. We identified 35 CEA studies (20 pneumococcal, 4 meningococcal, 8 rotavirus and 3 influenza vaccines) with 99 ICER-analyses (55 per-QALY, 27 per-LY and 17 per-DALY). The median ICER-absolute differences per QALY, LY and DALY (without minus with herd-protection) were $15,620 (IQR: $877 to $48,376); $54,871 (IQR: $787 to $115,026) and $49 (IQR: $15 to $1,636) respectively. When the target-vaccination strategy was not cost-saving without herd-protection, inclusion of herd-protection always resulted in more favorable results. In CEAs that had ICERs above the cost-effectiveness threshold without herd-protection, inclusion of herd-protection led to crossing of that threshold in 45% of the cases. This impacted only CEAs for more developed countries, as all but one CEAs for less developed countries had ICERs below the WHO-cost-effectiveness threshold even without herd-protection. In several analyses, recommendation for the adoption of the target

A Protective Vaccine against Chlamydia Genital Infection Using Vault Nanoparticles without an Added Adjuvant.

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Jiang, Janina; Liu, Guangchao; Kickhoefer, Valerie A; Rome, Leonard H; Li, Lin-Xi; McSorley, Stephen J; Kelly, Kathleen A

2017-01-19

Chlamydia trachomatis genital infection is the most common sexually transmitted bacterial disease, causing a significant burden to females due to reproductive dysfunction. Intensive screening and antibiotic treatment are unable to completely prevent female reproductive dysfunction, thus, efforts have become focused on developing a vaccine. A major impediment is identifying a safe and effective adjuvant which induces cluster of differentiation 4 (CD4) cells with attributes capable of halting genital infection and inflammation. Previously, we described a natural nanocapsule called the vault which was engineered to contain major outer membrane protein (MOMP) and was an effective vaccine which significantly reduced early infection and favored development of a cellular immune response in a mouse model. In the current study, we used another chlamydial antigen, a polymorphic membrane protein G-1 (PmpG) peptide, to track antigen-specific cells and evaluate, in depth, the vault vaccine for its protective capacity in the absence of an added adjuvant. We found PmpG-vault immunized mice significantly reduced the genital bacterial burden and histopathologic parameters of inflammation following a C. muridarum challenge. Immunization boosted antigen-specific CD4 cells with a multiple cytokine secretion pattern and reduced the number of inflammatory cells in the genital tract making the vault vaccine platform safe and effective for chlamydial genital infection. We conclude that vaccination with a Chlamydia -vault vaccine boosts antigen-specific immunities that are effective at eradicating infection and preventing reproductive tract inflammation.

A Protective Vaccine against Chlamydia Genital Infection Using Vault Nanoparticles without an Added Adjuvant

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Janina Jiang

2017-01-01

Full Text Available Chlamydia trachomatis genital infection is the most common sexually transmitted bacterial disease, causing a significant burden to females due to reproductive dysfunction. Intensive screening and antibiotic treatment are unable to completely prevent female reproductive dysfunction, thus, efforts have become focused on developing a vaccine. A major impediment is identifying a safe and effective adjuvant which induces cluster of differentiation 4 (CD4 cells with attributes capable of halting genital infection and inflammation. Previously, we described a natural nanocapsule called the vault which was engineered to contain major outer membrane protein (MOMP and was an effective vaccine which significantly reduced early infection and favored development of a cellular immune response in a mouse model. In the current study, we used another chlamydial antigen, a polymorphic membrane protein G-1 (PmpG peptide, to track antigen-specific cells and evaluate, in depth, the vault vaccine for its protective capacity in the absence of an added adjuvant. We found PmpG-vault immunized mice significantly reduced the genital bacterial burden and histopathologic parameters of inflammation following a C. muridarum challenge. Immunization boosted antigen-specific CD4 cells with a multiple cytokine secretion pattern and reduced the number of inflammatory cells in the genital tract making the vault vaccine platform safe and effective for chlamydial genital infection. We conclude that vaccination with a Chlamydia-vault vaccine boosts antigen-specific immunities that are effective at eradicating infection and preventing reproductive tract inflammation.

Harnessing naturally occurring tumor immunity: a clinical vaccine trial in prostate cancer.

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Mayu O Frank

2010-09-01

Full Text Available Studies of patients with paraneoplastic neurologic disorders (PND have revealed that apoptotic tumor serves as a potential potent trigger for the initiation of naturally occurring tumor immunity. The purpose of this study was to assess the feasibility, safety, and immunogenicity of an apoptotic tumor-autologous dendritic cell (DC vaccine.We have modeled PND tumor immunity in a clinical trial in which apoptotic allogeneic prostate tumor cells were used to generate an apoptotic tumor-autologous dendritic cell vaccine. Twenty-four prostate cancer patients were immunized in a Phase I, randomized, single-blind, placebo-controlled study to assess the safety and immunogenicity of this vaccine. Vaccinations were safe and well tolerated. Importantly, we also found that the vaccine was immunogenic, inducing delayed type hypersensitivity (DTH responses and CD4+ and CD8+ T cell proliferation, with no effect on FoxP3+ regulatory T cells. A statistically significant increase in T cell proliferation responses to prostate tumor cells in vitro (p = 0.002, decrease in prostate specific antigen (PSA slope (p = 0.016, and a two-fold increase in PSA doubling time (p = 0.003 were identified when we compared data before and after vaccination.An apoptotic cancer cell vaccine modeled on naturally occurring tumor immune responses in PND patients provides a safe and immunogenic tumor vaccine.ClinicalTrials.gov NCT00289341.

Development of novel double-decker microneedle patches for transcutaneous vaccine delivery.

Science.gov (United States)

Ono, Akihiko; Azukizawa, Hiroaki; Ito, Sayami; Nakamura, Yuki; Asada, Hideo; Quan, Ying-Shu; Kamiyama, Fumio; Katayama, Ichiro; Hirobe, Sachiko; Okada, Naoki

2017-10-30

Microneedle (MN) patches have great potential as transcutaneous vaccine delivery devices because MNs can effectively deliver vaccine antigen into the skin through the micropores formed in the stratum corneum by low-invasive and painless skin puncturing. This study aims to develop novel double-decker MN patches which have not only high safety and efficacy but also broad applicability to various vaccine antigens. We developed two types of MN patches (PGA-MN and Nylon-MN) that are made from polyglycolic acid and Nylon-6. In pre-clinical studies, both MN patches could demonstrably deliver antigens into resected human dermal tissue, prolong antigen deposition and increase antigen-specific IgG levels after vaccination compared with conventional injections. We demonstrated both MN patches could be safely applied to human skin because no broken MNs or significant skin irritation were observed after applications in the clinical research. PGA-MN was suggested to be superior to Nylon-MN regarding human skin puncturability based on measurements of transepidermal water loss and needle failure force. A high content of tetravalent influenza hemagglutinin antigens loaded on PGA-MN could stably maintain HA titers at 35°C for 1year. Overall, double-decker MN patches can reliably and safely puncture human skin and are promising as effective transcutaneous vaccine delivery devices. Copyright © 2017 Elsevier B.V. All rights reserved.

Zika virus-like particle (VLP) based vaccine

Science.gov (United States)

Boigard, Hélène; Alimova, Alexandra; Martin, George R.; Katz, Al; Gottlieb, Paul

2017-01-01

The newly emerged mosquito-borne Zika virus poses a major public challenge due to its ability to cause significant birth defects and neurological disorders. The impact of sexual transmission is unclear but raises further concerns about virus dissemination. No specific treatment or vaccine is currently available, thus the development of a safe and effective vaccine is paramount. Here we describe a novel strategy to assemble Zika virus-like particles (VLPs) by co-expressing the structural (CprME) and non-structural (NS2B/NS3) proteins, and demonstrate their effectiveness as vaccines. VLPs are produced in a suspension culture of mammalian cells and self-assembled into particles closely resembling Zika viruses as shown by electron microscopy studies. We tested various VLP vaccines and compared them to analogous compositions of an inactivated Zika virus (In-ZIKV) used as a reference. VLP immunizations elicited high titers of antibodies, as did the In-ZIKV controls. However, in mice the VLP vaccine stimulated significantly higher virus neutralizing antibody titers than comparable formulations of the In-ZIKV vaccine. The serum neutralizing activity elicited by the VLP vaccine was enhanced using a higher VLP dose and with the addition of an adjuvant, reaching neutralizing titers greater than those detected in the serum of a patient who recovered from a Zika infection in Brazil in 2015. Discrepancies in neutralization levels between the VLP vaccine and the In-ZIKV suggest that chemical inactivation has deleterious effects on neutralizing epitopes within the E protein. This along with the inability of a VLP vaccine to cause infection makes it a preferable candidate for vaccine development. PMID:28481898

Understanding vaccines: a public imperative.

Science.gov (United States)

Federman, Ross S

2014-12-01

Though once a discovery greatly celebrated by the nation, the vaccine has come under fire in recent decades from skeptics, critics, and a movement set into motion by fraudulent scientists and fueled by frustrated parents looking for answers to the autism conundrum. There is enough denialist resistance to vaccination to bring upon renewed fear of young children and infants becoming infected with diseases, the threats of which had been functionally eradicated from the United States. In more recent years, the surge in independent online journalism and blogging has invited many to rapidly share their opinions with millions of readers and, importantly, has appeared to open the door for opinion to be portrayed as fact. As a result, many parents are inundated with horror stories of vaccine dangers, all designed to eat away at them emotionally while the medical and scientific communities have mounted their characteristic response by sharing the facts, the data, and all of the reliable peer-reviewed and well-cited research to show that vaccines are safe and effective. It has become clear to me that facts are no match for emotion, but perhaps an understanding behind vaccine methodology will help parents overcome these fears of vaccinating. By helping those who doubt vaccines better understand what vaccines really are and how they work in such an incredibly engineered fashion, we may have a stronger weapon than we realize in battling the emotional arsenal that comes from the fear and skepticism of vaccinating.

Human Papilloma Virus Vaccine: Future of Cervical Cancer Prevention

Directory of Open Access Journals (Sweden)

Jannatul Fardows

2016-09-01

Full Text Available Cervical cancer is a deadly cancer that clutches lives of the women in most of the cases due to lack of consciousness about the disease in the developing countries. It remains a threat which is second only to breast cancer in overall disease burden for women throughout the world. Cervical cancer is almost a preventable disease by prophylactic vaccine and routine screening. Both Cervarix and Gardasil vaccines have been effective in preventing persistent infection with targeted HPV types and in preventing cervical intraepithelial lesions. It is safe and nearly 100% effective if given before onset of sexual activity. This review article is aimed to explore different aspects of this vaccine as well as to develop awareness among health professionals of different disciplines.

Increasing pandemic vaccination rates with effective communication.

Science.gov (United States)

Henrich, Natalie J

2011-06-01

Communicating effectively with the public about the importance of vaccination during a pandemic poses a challenge to health communicators. The public's concerns about the safety, effectiveness and necessity of vaccines lead many people to refuse vaccination and the current communication strategies are often unsuccessful at overcoming the public's resistance to vaccinate. Convincing the public to receive a vaccination, especially during a pandemic when there can be so much uncertainty about the vaccine and the disease, requires a revised communication approach. This revised approach should integrate into messages information that the public identifies as important, as well as presenting messages in a way that is consistent with our evolved social learning biases. These biases will impact both the content of the message and who delivers the message to different target populations. Additionally, an improved understanding between media and health communicators about the role each plays during a crisis may increase the effectiveness of messages disseminated to the public. Lastly, given that the public is increasingly seeking health information from on-line and other electronic sources, health communication needs to continue to find ways to integrate new technologies into communication strategies.

AIDS vaccine: Present status and future challenges

Directory of Open Access Journals (Sweden)

Nigam P

2006-01-01

Full Text Available Development of a preventive vaccine for HIV is the best hope of controlling the AIDS pandemic. HIV has, however, proved a difficult pathogen to vaccinate against because of its very high mutation rate and capability to escape immune responses. Neutralizing antibodies that can neutralize diverse field strains have so far proved difficult to induce. Adjuvanting these vaccines with cytokine plasmids and a "prime-boost," approach is being evaluated in an effort to induce both CTL and antibody responses and thereby have immune responses active against both infected cells and free viral particles, thereby necessitating fewer doses of recombinant protein to reach maximum antibodies titers. Although obstacles exist in evaluation of candidate HIV vaccines, evidence from natural history studies, new molecular tools in virology and immunology, new adjuvants, new gene expression systems, new antigen delivery systems, recent discoveries in HIV entry and pathogenesis, and promising studies of candidate vaccines in animal models have provided reasons to hope that developing a safe and effective AIDS vaccine is possible and within reach.

Vaccines licensed and in clinical trials for the prevention of dengue.

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Torresi, J; Ebert, G; Pellegrini, M

2017-05-04

Dengue has become a major global public health threat with almost half of the world's population living in at-risk areas. Vaccination would likely represent an effective strategy for the management of dengue disease in endemic regions, however to date there is only one licensed preventative vaccine for dengue infection. The development of a vaccine against dengue virus (DENV) has been hampered by an incomplete understanding of protective immune responses against DENV. The most clinically advanced dengue vaccine is the chimeric yellow fever-dengue vaccine (CYD) that employs the yellow fever virus 17D strain as the replication backbone (Chimerivax-DEN; CYD-TDV). This vaccine had an overall pooled protective efficacy of 65.6% but was substantially more effective against severe dengue and dengue hemorrhagic fever. Several other vaccine approaches have been developed including live attenuated chimeric dengue vaccines (DENVax and LAV Delta 30), DEN protein subunit V180 vaccine (DEN1-80E) and DENV DNA vaccines. These vaccines have been shown to be immunogenic in animals and also safe and immunogenic in humans. However, these vaccines are yet to progress to phase III trials to determine their protective efficacy against dengue. This review will summarize the details of vaccines that have progressed to clinical trials in humans.

Development of a novel oral vaccine against Mycobacterium avium paratuberculosis and Johne disease

Science.gov (United States)

Johnston, C; Coffey, A; Sleator, RD

2010-01-01

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne disease, a granulomatous enteritis of cattle and other domesticated and wild ruminant species. Johne disease is prevalent worldwide and has a significant impact on the global agricultural economy. Current vaccines against Johne are insufficient in stemming its spread, and associated side-effects prevent their widespread use in control programs. Effective and safe vaccine strategies are needed. The main purpose of this paper is to propose and evaluate the development of a novel oral subunit-vaccine using a patho-biotechnological approach. This novel strategy, which harnesses patho-genetic elements from the intracellular pathogen Listeria monocytogenes, may provide a realistic route towards developing an effective next generation subunit vaccine against Johne disease and paratuberculosis. PMID:21326921

DNA fusion gene vaccines

DEFF Research Database (Denmark)

Holst, Peter Johannes; Bassi, Maria Rosaria; Thomsen, Allan Randrup

2010-01-01

DNA vaccines are versatile and safe, but limited immunogenicity has prevented their use in the clinical setting. Experimentally, immunogenicity may be enhanced by the use of new delivery technologies, by coadministration of cytokines and pathogen-associated molecular patterns, or by fusion...... of antigens into molecular domains that enhance antigen presentation. More specifically, the immunogenicity of DNA vaccines may benefit from increased protein synthesis, increased T-cell help and MHC class I presentation, and the addition of a range of specific cytokines and pathogen-associated molecular...... with viral-vectored vaccines, various synergistic components may need to be incorporated into DNA vaccines. From the perspective of the future clinical use of DNA vaccines, it has been suggested that antigen presentation should be improved and cytokine coadministration attempted. However, even...

Nonspecific effects of neonatal and infant vaccination

DEFF Research Database (Denmark)

Aaby, Peter; Kollmann, Tobias R; Benn, Christine Stabell

2014-01-01

Vaccines can have nonspecific effects through their modulation of responses to infections not specifically targeted by the vaccine. However, lack of knowledge about the underlying immunological mechanisms and molecular cause-and-effect relationships prevent use of this potentially powerful early-...

[Effectiveness, population-level effects, and heath economics of measles and rubella vaccination].

Science.gov (United States)

Wichmann, O; Ultsch, B

2013-09-01

Vaccination against measles and rubella has been included in national immunization programs worldwide for several decades. In this article, we present the evidence related to the effectiveness of measles and rubella vaccination based on published systematic reviews, and we describe the epidemiological and health economic effects of vaccination at a population level. Several observational studies demonstrate the high effectiveness (> 90 %) of both measles and rubella vaccination. The global measles mortality reduction and the dramatic decrease in rubella and measles incidences after introduction of routine immunization contribute to the very high quality of evidence. The countries of the Americas have proved that it is feasible to eliminate measles and rubella by strengthening infant immunization through routine vaccination services and by conducting supplemental immunization activities in other childhood age groups so as to close immunity gaps. An economic evaluation of measles and rubella vaccination specifically for the healthcare system in Germany does not exist. However, we conducted a systematic review and identified 11 health-economic studies from other industrialized countries and one for a hypothetical industrialized country. Results indicate that vaccination against measles and rubella had either a cost-effective or even a cost-saving potential, which could be assumed with some limitations also for the German setting. In conclusion, there is compelling evidence that the available vaccines are very effective and that measles and rubella elimination is feasible if adequate vaccination strategies are implemented. In Germany, catch-up vaccination programs are urgently needed for children, adolescents, and young adults specifically in the western federal states.

VACCINATION AGAINST HUMAN PAPILLOMAVIRUS INFECTION: A SAFE SOLUTION TO THE GLOBAL PROBLEM

Directory of Open Access Journals (Sweden)

M.G. Galitskaya

2011-01-01

Full Text Available The problem of diagnosis, prevention and treatment of diseases caused by human papilloma virus (HPV, in recent years has become more urgent, not only for physicians, scientists, but also for patients. This is due to the high contagiousness of HPV, its prevalence and, of course, proved oncogenicity. Creation and introduction of preventive vaccines against the most common HPV types played a definite role in the global health, and, of course, raised the attention of doctors and the public to human papillomavirus infection and associated diseases. At the same time propaganda against vaccination blocks the widespread adoption of this disease prevention in our country. In this paper, we introduce the American experience of monitoring vaccination adverse events.Key words: human papillomavirus infection, prevention, vaccination, adverse events, monitoring, children.

The Potential of Vaccines for the Control of AIDS

Directory of Open Access Journals (Sweden)

Margaret I Johnston

1994-01-01

of attenuated and whole-killed products have led to the pursuit of alternativc designs. including recombinant proteins, vectors and particles, synthetic peptides and naked DNA. Seven recombinant envelope. two recombinant vector and four other candidate vaccines that have entered into phase 1 trials in noninfected individuals have proven safe to date, and have differed In their ability lo induce functional antibody and Cytotoxic T lymphocytes. Two recombinant envelope products have recently progressed to phase 2 testing, Five envelope-based and six other products have entered trial in HIV-infected and individuals and have appeared to be safe, Evidence of new antibody, increased T cell proliferation and lncreased cytotoxic T lymphocyte activity have been reported. Additional placebo controlled trials will be required to evaluate the impact of therapeutic vaccination on CD4 cell count. viral burdrn and clinical end-points. The status of HIV/AIDS vaccine development is reviewed. with emphasis on the challenging task of finding an effieacious, safe, prophylactic vaccine.

Vaccines. An Ebola whole-virus vaccine is protective in nonhuman primates.

Science.gov (United States)

Marzi, Andrea; Halfmann, Peter; Hill-Batorski, Lindsay; Feldmann, Friederike; Shupert, W Lesley; Neumann, Gabriele; Feldmann, Heinz; Kawaoka, Yoshihiro

2015-04-24

Zaire ebolavirus is the causative agent of the current outbreak of hemorrhagic fever disease in West Africa. Previously, we showed that a whole Ebola virus (EBOV) vaccine based on a replication-defective EBOV (EBOVΔVP30) protects immunized mice and guinea pigs against lethal challenge with rodent-adapted EBOV. Here, we demonstrate that EBOVΔVP30 protects nonhuman primates against lethal infection with EBOV. Although EBOVΔVP30 is replication-incompetent, we additionally inactivated the vaccine with hydrogen peroxide; the chemically inactivated vaccine remained antigenic and protective in nonhuman primates. EBOVΔVP30 thus represents a safe, efficacious, whole-EBOV vaccine candidate that differs from other EBOV vaccine platforms in that it presents all viral proteins and the viral RNA to the host immune system, which might contribute to protective immune responses. Copyright © 2015, American Association for the Advancement of Science.

Increasing vaccine production using pulsed ultrasound waves.

Directory of Open Access Journals (Sweden)

Jida Xing

Full Text Available Vaccination is a safe and effective approach to prevent deadly diseases. To increase vaccine production, we propose that a mechanical stimulation can enhance protein production. In order to prove this hypothesis, Sf9 insect cells were used to evaluate the increase in the expression of a fusion protein from hepatitis B virus (HBV S1/S2. We discovered that the ultrasound stimulation at a frequency of 1.5 MHz, intensity of 60 mW/cm2, for a duration of 10 minutes per day increased HBV S1/S2 by 27%. We further derived a model for transport through a cell membrane under the effect of ultrasound waves, tested the key assumptions of the model through a molecular dynamics simulation package, NAMD (Nanoscale Molecular Dynamics program and utilized CHARMM force field in a steered molecular dynamics environment. The results show that ultrasound waves can increase cell permeability, which, in turn, can enhance nutrient / waste exchange thus leading to enhanced vaccine production. This finding is very meaningful in either shortening vaccine production time, or increasing the yield of proteins for use as vaccines.

Evolution of Live-Attenuated HIV Vaccines

NARCIS (Netherlands)

Berkhout, Ben

2011-01-01

Despite intensive research since the viral pathogen was discovered some 25 years ago, not much progress has been reported on the development of a safe vaccine that protects against human immunodeficiency virus type 1. A vaccine approach that has been abandoned because its safety cannot be guaranteed

Therapeutic HIV Peptide Vaccine

DEFF Research Database (Denmark)

Fomsgaard, Anders

2015-01-01

Therapeutic vaccines aim to control chronic HIV infection and eliminate the need for lifelong antiretroviral therapy (ART). Therapeutic HIV vaccine is being pursued as part of a functional cure for HIV/AIDS. We have outlined a basic protocol for inducing new T cell immunity during chronic HIV-1...... infection directed to subdominant conserved HIV-1 epitopes restricted to frequent HLA supertypes. The rationale for selecting HIV peptides and adjuvants are provided. Peptide subunit vaccines are regarded as safe due to the simplicity, quality, purity, and low toxicity. The caveat is reduced immunogenicity...

Varicella and herpes zoster vaccine development: lessons learned.

Science.gov (United States)

Warren-Gash, Charlotte; Forbes, Harriet; Breuer, Judith

2017-12-01

Before vaccination, varicella zoster virus (VZV), which is endemic worldwide, led to almost universal infection. This neurotropic virus persists lifelong by establishing latency in sensory ganglia, where its reactivation is controlled by VZV-specific T-cell immunity. Lifetime risk of VZV reactivation (zoster) is around 30%. Vaccine development was galvanised by the economic and societal burden of VZV, including debilitating zoster complications that largely affect older individuals. Areas covered: We describe the story of development, licensing and implementation of live attenuated vaccines against varicella and zoster. We consider the complex backdrop of VZV virology, pathogenesis and immune responses in the absence of suitable animal models and examine the changing epidemiology of VZV disease. We review the vaccines' efficacy, safety, effectiveness and coverage using evidence from trials, observational studies from large routine health datasets and clinical post-marketing surveillance studies and outline newer developments in subunit and inactivated vaccines. Expert commentary: Safe and effective, varicella and zoster vaccines have already made major inroads into reducing the burden of VZV disease globally. As these live vaccines have the potential to reactivate and cause clinical disease, developing alternatives that do not establish latency is an attractive prospect but will require better understanding of latency mechanisms.

Strategies & recent development of transmission-blocking vaccines against Plasmodium falciparum

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Neha Chaturvedi

2016-01-01

Full Text Available Transmission blocking malaria vaccines are aimed to block the development and maturity of sexual stages of parasite within mosquitoes. The vaccine candidate antigens (Pfs25, Pfs48/45, Pfs230 that have shown transmission blocking immunity in model systems are in different stages of development. These antigens are immunogenic with limited genetic diversity. Pfs25 is a leading candidate and currently in phase I clinical trial. Efforts are now focused on the cost-effective production of potent antigens using safe adjuvants and optimization of vaccine delivery system that are capable of inducing strong immune responses. This review addresses the potential usefulness, development strategies, challenges, clinical trials and current status of Plasmodium falciparum sexual stage malaria vaccine candidate antigens for the development of transmission-blocking vaccines.

Novel vaccines to human rabies.

Directory of Open Access Journals (Sweden)

Hildegund C J Ertl

Full Text Available Rabies, the most fatal of all infectious diseases, remains a major public health problem in developing countries, claiming the lives of an estimated 55,000 people each year. Most fatal rabies cases, with more than half of them in children, result from dog bites and occur among low-income families in Southeast Asia and Africa. Safe and efficacious vaccines are available to prevent rabies. However, they have to be given repeatedly, three times for pre-exposure vaccination and four to five times for post-exposure prophylaxis (PEP. In cases of severe exposure, a regimen of vaccine combined with a rabies immunoglobulin (RIG preparation is required. The high incidence of fatal rabies is linked to a lack of knowledge on the appropriate treatment of bite wounds, lack of access to costly PEP, and failure to follow up with repeat immunizations. New, more immunogenic but less costly rabies virus vaccines are needed to reduce the toll of rabies on human lives. A preventative vaccine used for the immunization of children, especially those in high incidence countries, would be expected to lower fatality rates. Such a vaccine would have to be inexpensive, safe, and provide sustained protection, preferably after a single dose. Novel regimens are also needed for PEP to reduce the need for the already scarce and costly RIG and to reduce the number of vaccine doses to one or two. In this review, the pipeline of new rabies vaccines that are in pre-clinical testing is provided and an opinion on those that might be best suited as potential replacements for the currently used vaccines is offered.

DNA/MVA Vaccines for HIV/AIDS

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Smita S. Iyer

2014-02-01

Full Text Available Since the initial proof-of-concept studies examining the ability of antigen-encoded plasmid DNA to serve as an immunogen, DNA vaccines have evolved as a clinically safe and effective platform for priming HIV-specific cellular and humoral responses in heterologous “prime-boost” vaccination regimens. Direct injection of plasmid DNA into the muscle induces T- and B-cell responses against foreign antigens. However, the insufficient magnitude of this response has led to the development of approaches for enhancing the immunogenicity of DNA vaccines. The last two decades have seen significant progress in the DNA-based vaccine platform with optimized plasmid constructs, improved delivery methods, such as electroporation, the use of molecular adjuvants and novel strategies combining DNA with viral vectors and subunit proteins. These innovations are paving the way for the clinical application of DNA-based HIV vaccines. Here, we review preclinical studies on the DNA-prime/modified vaccinia Ankara (MVA-boost vaccine modality for HIV. There is a great deal of interest in enhancing the immunogenicity of DNA by engineering DNA vaccines to co-express immune modulatory adjuvants. Some of these adjuvants have demonstrated encouraging results in preclinical and clinical studies, and these data will be examined, as well.

Intranasal Immunization Using Mannatide as a Novel Adjuvant for an Inactivated Influenza Vaccine and Its Adjuvant Effect Compared with MF59.

Directory of Open Access Journals (Sweden)

Shu-Ting Ren

Full Text Available Intranasal vaccination is more potent than parenteral injection for the prevention of influenza. However, because the poor efficiency of antigen uptake across the nasal mucosa is a key issue, immunostimulatory adjuvants are essential for intranasal vaccines. The immunomodulator mannatide or polyactin (PA has been used for the clinical treatment of impaired immunity in China, but its adjuvant effect on an inactivated trivalent influenza vaccine (ITIV via intranasal vaccination is unclear. To explore the adjuvant effect of PA, an inactivated trivalent influenza virus with or without PA or MF59 was instilled intranasally once a week in BALB/c mice. Humoral immunity was assessed by both the ELISA and hemagglutination inhibition (HI methods using antigen-specific antibodies. Splenic lymphocyte proliferation and the IFN-γ level were measured to evaluate cell-mediated immunity. The post-vaccination serum HI antibody geometric mean titers (GMTs for the H1N1 and H3N2 strains, antigen-specific serum IgG and IgA GMTs, mucosal SIgA GMT, splenic lymphocyte proliferation, and IFN-γ were significantly increased in the high-dose PA-adjuvanted vaccine group. The seroconversion rate and the mucosal response for the H3N2 strain were significantly elevated after high-dose PA administration. These adjuvant effects of high-dose PA for the influenza vaccine were comparable with those of the MF59 adjuvant, and abnormal signs or pathological changes were not found in the evaluated organs. In conclusion, PA is a novel mucosal adjuvant for intranasal vaccination with the ITIV that has safe and effective mucosal adjuvanticity in mice and successfully induces both serum and mucosal antibody responses and a cell-mediated response.

Effective or ineffective: attribute framing and the human papillomavirus (HPV) vaccine.

Science.gov (United States)

Bigman, Cabral A; Cappella, Joseph N; Hornik, Robert C

2010-12-01

To experimentally test whether presenting logically equivalent, but differently valenced effectiveness information (i.e. attribute framing) affects perceived effectiveness of the human papillomavirus (HPV) vaccine, vaccine-related intentions and policy opinions. A survey-based experiment (N=334) was fielded in August and September 2007 as part of a larger ongoing web-enabled monthly survey, the Annenberg National Health Communication Survey. Participants were randomly assigned to read a short passage about the HPV vaccine that framed vaccine effectiveness information in one of five ways. Afterward, they rated the vaccine and related opinion questions. Main statistical methods included ANOVA and t-tests. On average, respondents exposed to positive framing (70% effective) rated the HPV vaccine as more effective and were more supportive of vaccine mandate policy than those exposed to the negative frame (30% ineffective) or the control frame. Mixed valence frames showed some evidence for order effects; phrasing that ended by emphasizing vaccine ineffectiveness showed similar vaccine ratings to the negative frame. The experiment finds that logically equivalent information about vaccine effectiveness not only influences perceived effectiveness, but can in some cases influence support for policies mandating vaccine use. These framing effects should be considered when designing messages. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Effective or ineffective: Attribute framing and the human papillomavirus (HPV) vaccine

Science.gov (United States)

Bigman, Cabral A.; Cappella, Joseph N.; Hornik, Robert C.

2010-01-01

Objectives To experimentally test whether presenting logically equivalent, but differently valenced effectiveness information (i.e. attribute framing) affects perceived effectiveness of the human papillomavirus (HPV) vaccine, vaccine related intentions and policy opinions. Method A survey-based experiment (N= 334) was fielded in August and September 2007 as part of a larger ongoing web-enabled monthly survey, the Annenberg National Health Communication Survey. Participants were randomly assigned to read a short passage about the HPV vaccine that framed vaccine effectiveness information in one of five ways. Afterward, they rated the vaccine and related opinion questions. Main statistical methods included ANOVA and t-tests. Results On average, respondents exposed to positive framing (70% effective) rated the HPV vaccine as more effective and were more supportive of vaccine mandate policy than those exposed to the negative frame (30% ineffective) or the control frame. Mixed valence frames showed some evidence for order effects; phrasing that ended by emphasizing vaccine ineffectiveness showed similar vaccine ratings to the negative frame. Conclusions The experiment finds that logically equivalent information about vaccine effectiveness not only influences perceived effectiveness, but can in some cases influence support for policies mandating vaccine use. Practice implications These framing effects should be considered when designing messages. PMID:20851560

Social Justice and HIV Vaccine Research in the Age of Pre-Exposure Prophylaxis and Treatment as Prevention

Science.gov (United States)

Bailey, Theodore C.; Sugarman, Jeremy

2014-01-01

The advent of pre-exposure prophylaxis (PrEP) and treatment as prevention (TasP) as means of HIV prevention raises issues of justice concerning how most fairly and equitably to apportion resources in support of the burgeoning variety of established HIV treatment and prevention measures and further HIV research, including HIV vaccine research. We apply contemporary approaches to social justice to assess the ethical justification for allocating resources in support of HIV vaccine research given competing priorities to support broad implementation of HIV treatment and prevention measures, including TasP and PrEP. We argue that there is prima facie reason to believe that a safe and effective preventive HIV vaccine would offer a distinct set of ethically significant benefits not provided by current HIV treatment or prevention methods. It is thereby possible to justify continued support for HIV vaccine research despite tension with priorities for treatment, prevention, and other research. We then consider a counter-argument to such a justification based on the uncertainty of successfully developing a safe and effective preventive HIV vaccine. Finally, we discuss how HIV vaccine research might now be ethically designed and conducted given the new preventive options of TasP and PrEP, focusing on the ethically appropriate standard of prevention for HIV vaccine trials. PMID:24033297

Viable adenovirus vaccine prototypes: High-level production of a papillomavirus capsid antigen from the major late transcriptional unit

OpenAIRE

Berg, Michael; DiFatta, Julie; Hoiczyk, Egbert; Schlegel, Richard; Ketner, Gary

2005-01-01

Safe, effective, orally delivered, live adenovirus vaccines have been in use for three decades. Recombinant derivatives of the live adenovirus vaccines may prove an economical alternative to current vaccines for a variety of diseases. To explore that possibility, we constructed a series of recombinants that express the major capsid protein (L1) of canine oral papillomavirus (COPV), a model for mucosal human papillomavirus (HPV) infection. Vaccination with virus-like particles (VLPs) composed ...

Use of the live attenuated Japanese Encephalitis vaccine SA 14-14-2 in children: A review of safety and tolerability studies.

Science.gov (United States)

Ginsburg, Amy Sarah; Meghani, Ankita; Halstead, Scott B; Yaich, Mansour

2017-10-03

Japanese encephalitis (JE) is the leading cause of viral neurological disease and disability in Asia. Some 50-80% of children with clinical JE die or have long-term neurologic sequelae. Since there is no cure, human vaccination is the only effective long-term control measure, and the World Health Organization recommends that at-risk populations receive a safe and effective vaccine. Four different types of JE vaccines are currently available: inactivated mouse brain-derived vaccines, inactivated Vero cell vaccines, live attenuated SA 14-14-2 vaccines and a live recombinant (chimeric) vaccine. With the rapidly increasing demand for and availability and use of JE vaccines, countries face an important decision in the selection of a JE vaccine. This article provides a comprehensive review of the available safety literature for the live attenuated SA 14-14-2 JE vaccine (LAJEV), the most widely used new generation JE vaccine. With well-established effectiveness data, a single dose of LAJEV protects against clinical JE disease for at least 5 years, providing a long duration of protection compared with inactivated mouse brain-derived vaccines. Since 1988, about 700 million doses of the LAJEV have been distributed globally. Our review found that LAJEV is well tolerated across a wide age range and can safely be given to children as young as 8 months of age. While serious adverse events attributable to LAJEV have been reported, independent experts have not found sufficient evidence for causality based on the available data.

Recombinant canine distemper virus serves as bivalent live vaccine against rabies and canine distemper.

Science.gov (United States)

Wang, Xijun; Feng, Na; Ge, Jinying; Shuai, Lei; Peng, Liyan; Gao, Yuwei; Yang, Songtao; Xia, Xianzhu; Bu, Zhigao

2012-07-20

Effective, safe, and affordable rabies vaccines are still being sought. Attenuated live vaccine has been widely used to protect carnivores from canine distemper. In this study, we generated a recombinant canine distemper virus (CDV) vaccine strain, rCDV-RVG, expressing the rabies virus glycoprotein (RVG) by using reverse genetics. The recombinant virus rCDV-RVG retained growth properties similar to those of vector CDV in Vero cell culture. Animal studies demonstrated that rCDV-RVG was safe in mice and dogs. Mice inoculated intracerebrally or intramuscularly with rCDV-RVG showed no apparent signs of disease and developed a strong rabies virus (RABV) neutralizing antibody response, which completely protected mice from challenge with a lethal dose of street virus. Canine studies showed that vaccination with rCDV-RVG induced strong and long-lasting virus neutralizing antibody responses to RABV and CDV. This is the first study demonstrating that recombinant CDV has the potential to serve as bivalent live vaccine against rabies and canine distemper in animals. Copyright © 2012 Elsevier Ltd. All rights reserved.

Plant-derived vaccine protects target animals against a viral disease

NARCIS (Netherlands)

Dalsgaard, K.; Uttenthal, A.; Jones, T.D.; Xu, F.; Merrywater, A.; Hamilton, W.D.O.; Langeveld, J.P.M.; Boshuizen, R.S.; Kamstrup, S.; Lomonos, G.P.

1997-01-01

The successful expression of animal or human virus epitopes on the surface of plant viruses has recently been demonstrated. These chimeric virus particles (CVPs) could represent a cost-effective and safe alternative to conventional animal cell-based vaccines. We report the insertion of

Induction of respiratory immune responses in the chicken; implications for development of mucosal avian influenza virus vaccines

NARCIS (Netherlands)

Geus, de E.D.; Rebel, J.M.J.; Vervelde, L.

2012-01-01

The risk and the size of an outbreak of avian influenza virus (AIV) could be restricted by vaccination of poultry. A vaccine used for rapid intervention during an AIV outbreak should be safe, highly effective after a single administration and suitable for mass application. In the case of AIV,

Enhancement of the Immunogenicity and Protective Efficacy of a Mucosal Influenza Subunit Vaccine by the Saponin Adjuvant GPI-0100

NARCIS (Netherlands)

Liu, Heng; Patil, Harshad P.; de Vries-Idema, Jacqueline; Wilschut, Jan; Huckriede, Anke

2012-01-01

Identification of safe and effective adjuvants remains an urgent need for the development of inactivated influenza vaccines for mucosal administration. Here, we used a murine challenge model to evaluate the adjuvant activity of GPI-0100, a saponin-derived adjuvant, on influenza subunit vaccine

A multi-country study of dengue vaccination strategies with Dengvaxia and a future vaccine candidate in three dengue-endemic countries: Vietnam, Thailand, and Colombia.

Science.gov (United States)

Lee, Jung-Seok; Lourenço, José; Gupta, Sunetra; Farlow, Andrew

2018-04-19

The dengue vaccination era began when Dengvaxia (CYD-TDV) became available in 2016. In addition, several second-generation vaccine candidates are currently in phase 3 trials, suggesting that a broader availability of dengue vaccines may be possible in the near future. Advancing on the recent WHO-SAGE recommendations for the safe and effective use of CYD-TDV at the regional level on average, this study investigates the vaccination impacts and cost-effectiveness of CYD-TDV and of a hypothetical new vaccine candidate (NVC) in a country-specific manner for three endemic countries: Vietnam, Thailand, and Colombia. The vaccination impacts of CYD-TDV and NVC were derived by fitting the empirical seroprevalence rates of 9 year olds into an individual-based meta-population transmission model, previously used for the WHO-SAGE working group. The disability-adjusted life years were estimated by applying country-specific parametric values. The cost-effectiveness analyses of four intervention strategies in combination with routine and catch-up campaigns were compared for both vaccines to inform decision makers regarding the most suitable immunization program in each of the three countries. Both CYD-TDV and NVC could be cost-effective at the DALY threshold cost of $2000 depending upon vaccination costs. With CYD-TDV, targeting 9 year olds in routine vaccination programs and 10-29 year olds as a one-off catch-up campaign was the most cost-effective strategy in all three countries. With NVC, while the most cost-effective strategy was to vaccinate 9-29 and 9-18 year olds in Vietnam and Thailand respectively, vaccinating younger age cohorts between 1 and 5 years old in Colombia was more cost-effective than other strategies. Given that three countries will soon face decisions regarding whether and how to incorporate CYD-TDV or future dengue vaccines into their budget-constrained national immunization programs, the current study outcomes can be used to help decision makers

The safety of influenza vaccines in children: An Institute for Vaccine Safety white paper.

Science.gov (United States)

Halsey, Neal A; Talaat, Kawsar R; Greenbaum, Adena; Mensah, Eric; Dudley, Matthew Z; Proveaux, Tina; Salmon, Daniel A

2015-12-30

Most influenza vaccines are generally safe, but influenza vaccines can cause rare serious adverse events. Some adverse events, such as fever and febrile seizures, are more common in children than adults. There can be differences in the safety of vaccines in different populations due to underlying differences in genetic predisposition to the adverse event. Live attenuated vaccines have not been studied adequately in children under 2 years of age to determine the risks of adverse events; more studies are needed to address this and several other priority safety issues with all influenza vaccines in children. All vaccines intended for use in children require safety testing in the target age group, especially in young children. Safety of one influenza vaccine in children should not be extrapolated to assumed safety of all influenza vaccines in children. The low rates of adverse events from influenza vaccines should not be a deterrent to the use of influenza vaccines because of the overwhelming evidence of the burden of disease due to influenza in children. Copyright © 2016. Published by Elsevier Ltd.

Suspected YF-AND after yellow fever vaccination in Finland.

Science.gov (United States)

Jääskeläinen, Anne J; Huhtamo, Eili; Kivioja, Reetta; Domingo, Cristina; Vene, Sirkka; Kallio-Kokko, Hannimari; Niedrig, Matthias; Tienari, Pentti J; Vapalahti, Olli

2014-11-01

Yellow fever (YF) vaccine is considered safe but vaccine-associated complications have also been encountered. We report neurological symptoms after YF-vaccination in a previously healthy Finnish male. Other concomitant infections or causes for the symptoms could not be identified. Copyright © 2014 Elsevier B.V. All rights reserved.

Feasibility of conducting intradermal vaccination campaign with inactivated poliovirus vaccine using Tropis intradermal needle free injection system, Karachi, Pakistan.

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Yousafzai, Mohammad Tahir; Saleem, Ali Faisal; Mach, Ondrej; Baig, Attaullah; Sutter, Roland W; Zaidi, Anita K M

2017-08-01

Administration of intradermal fractional dose of inactivated poliovirus vaccine (fIPV) has proven to be safe and immunogenic; however, its intradermal application using needle and syringe is technically difficult and requires trained personnel. We assessed feasibility of conducting an intradermal fIPV campaign in polio high risk neighborhood of Karachi using Tropis needle-free injector. During the one-day fIPV campaign, we measured average "application time" to administer fIPV with Tropis, collected ergonomic information and measured vaccine wastage. Eleven vaccinator teams, after two-day training, immunized 582 children between 4 months and 5 years of age. Average "application time" ranged from 35-75 seconds; the "application time" decreased with the number of children vaccinated from 68 to 38 seconds between 1st and 30th child. 10/11 (91%) vaccinator teams found no ergonomic issues; 1/11 (9%) assessed that it was not easy to remove air bubbles when filling the device. There was 0% vaccine loss reported. No adverse events following immunizations were reported. We demonstrated that it is feasible, safe and efficient to use Tropis for the administration of fIPV in a campaign setting.

The cost-effectiveness of rotavirus vaccination in Armenia.

Science.gov (United States)

Jit, Mark; Yuzbashyan, Ruzanna; Sahakyan, Gayane; Avagyan, Tigran; Mosina, Liudmila

2011-11-08

The cost-effectiveness of introducing infant rotavirus vaccination in Armenia in 2012 using Rotarix(R) was evaluated using a multiple birth cohort model. The model considered the cost and health implications of hospitalisations, primary health care consultations and episodes not leading to medical care in children under five years old. Rotavirus vaccination is expected to cost the Ministry of Health $220,000 in 2012, rising to $830,000 in 2016 following termination of GAVI co-financing, then declining to $260,000 in 2025 due to vaccine price maturity. It may reduce health care costs by $34,000 in the first year, rising to $180,000 by 2019. By 2025, vaccination may be close to cost saving to the Ministry of Health if the vaccine purchase price declines as expected. Once coverage has reached high levels, vaccination may prevent 25,000 cases, 3000 primary care consultations, 1000 hospitalisations and 8 deaths per birth cohort vaccinated. The cost per disability-adjusted life year (DALY) saved is estimated to be about $650 from the perspective of the Ministry of Health, $850 including costs accrued to both the Ministry and to GAVI, $820 from a societal perspective excluding indirect costs and $44 from a societal perspective including indirect costs. Since the gross domestic product per capita of Armenia in 2008 was $3800, rotavirus vaccination is likely to be regarded as "very cost-effective" from a WHO standpoint. Vaccination may still be "very cost-effective" if less favourable assumptions are used regarding vaccine price and disease incidence, as long as DALYs are not age-weighted. Copyright © 2011 Elsevier Ltd. All rights reserved.

Case-control vaccine effectiveness studies: Data collection, analysis and reporting results.

Science.gov (United States)

Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

2017-06-05

The case-control methodology is frequently used to evaluate vaccine effectiveness post-licensure. The results of such studies provide important insight into the level of protection afforded by vaccines in a 'real world' context, and are commonly used to guide vaccine policy decisions. However, the potential for bias and confounding are important limitations to this method, and the results of a poorly conducted or incorrectly interpreted case-control study can mislead policies. In 2012, a group of experts met to review recent experience with case-control studies evaluating vaccine effectiveness; we summarize the recommendations of that group regarding best practices for data collection, analysis, and presentation of the results of case-control vaccine effectiveness studies. Vaccination status is the primary exposure of interest, but can be challenging to assess accurately and with minimal bias. Investigators should understand factors associated with vaccination as well as the availability of documented vaccination status in the study context; case-control studies may not be a valid method for evaluating vaccine effectiveness in settings where many children lack a documented immunization history. To avoid bias, it is essential to use the same methods and effort gathering vaccination data from cases and controls. Variables that may confound the association between illness and vaccination are also important to capture as completely as possible, and where relevant, adjust for in the analysis according to the analytic plan. In presenting results from case-control vaccine effectiveness studies, investigators should describe enrollment among eligible cases and controls as well as the proportion with no documented vaccine history. Emphasis should be placed on confidence intervals, rather than point estimates, of vaccine effectiveness. Case-control studies are a useful approach for evaluating vaccine effectiveness; however careful attention must be paid to the collection

Effects of a nurse-managed program on hepatitis A and B vaccine completion among homeless adults.

Science.gov (United States)

Nyamathi, Adeline; Liu, Yihang; Marfisee, Mary; Shoptaw, Steven; Gregerson, Paul; Saab, Sammy; Leake, Barbara; Tyler, Darlene; Gelberg, Lillian

2009-01-01

Hepatitis B virus (HBV) infection constitutes a major health problem for homeless persons. Ability to complete an HBV vaccination series is complicated by the need to prioritize competing needs, such as addiction issues, safe places to sleep, and food, over health concerns. The objectives of this study were to evaluate the effectiveness of a nurse-case-managed intervention compared with that of two standard programs on completion of the combined hepatitis A virus (HAV) and HBV vaccine series among homeless adults and to assess sociodemographic factors and risk behaviors related to the vaccine completion. A randomized, three-group, prospective, quasi-experimental design was conducted with 865 homeless adults residing in homeless shelters, drug rehabilitation sites, and outdoor areas in the Skid Row area of Los Angeles. The programs included (a) nurse-case-managed sessions plus targeted hepatitis education, incentives, and tracking (NCMIT); (b) standard targeted hepatitis education plus incentives and tracking (SIT); and (c) standard targeted hepatitis education and incentives only (SI). Sixty-eight percent of the NCMIT participants completed the three-series vaccine at 6 months, compared with 61% of SIT participants and 54% of SI participants. NCMIT participants had almost 2 times greater odds of completing vaccination than those of participants in the SI program. Completers were more likely to be older, to be female, to report fair or poor health, and not to have participated in a self-help drug treatment program. Newly homeless White adults were significantly less likely than were African Americans to complete the vaccine series. The use of vaccination programs incorporating nurse case management and tracking is critical in supporting adherence to completion of a 6-month HAV/HBV vaccine. The finding that White homeless persons were the least likely to complete the vaccine series suggests that programs tailored to address their unique cultural issues are needed.

In vivo electroporation enhances the immunogenicity of an HIV-1 DNA vaccine candidate in healthy volunteers.

Directory of Open Access Journals (Sweden)

Sandhya Vasan

Full Text Available DNA-based vaccines have been safe but weakly immunogenic in humans to date.We sought to determine the safety, tolerability, and immunogenicity of ADVAX, a multigenic HIV-1 DNA vaccine candidate, injected intramuscularly by in vivo electroporation (EP in a Phase-1, double-blind, randomized placebo-controlled trial in healthy volunteers. Eight volunteers each received 0.2 mg, 1 mg, or 4 mg ADVAX or saline placebo via EP, or 4 mg ADVAX via standard intramuscular injection at weeks 0 and 8. A third vaccination was administered to eleven volunteers at week 36. EP was safe, well-tolerated and considered acceptable for a prophylactic vaccine. EP delivery of ADVAX increased the magnitude of HIV-1-specific cell mediated immunity by up to 70-fold over IM injection, as measured by gamma interferon ELISpot. The number of antigens to which the response was detected improved with EP and increasing dosage. Intracellular cytokine staining analysis of ELISpot responders revealed both CD4+ and CD8+ T cell responses, with co-secretion of multiple cytokines.This is the first demonstration in healthy volunteers that EP is safe, tolerable, and effective in improving the magnitude, breadth and durability of cellular immune responses to a DNA vaccine candidate.ClinicalTrials.gov NCT00545987.

Current status of multiple antigen-presenting peptide vaccine systems: Application of organic and inorganic nanoparticles

Directory of Open Access Journals (Sweden)

Taguchi Hiroaki

2011-08-01

Full Text Available Abstract Many studies are currently investigating the development of safe and effective vaccines to prevent various infectious diseases. Multiple antigen-presenting peptide vaccine systems have been developed to avoid the adverse effects associated with conventional vaccines (i.e., live-attenuated, killed or inactivated pathogens, carrier proteins and cytotoxic adjuvants. Recently, two main approaches have been used to develop multiple antigen-presenting peptide vaccine systems: (1 the addition of functional components, e.g., T-cell epitopes, cell-penetrating peptides, and lipophilic moieties; and (2 synthetic approaches using size-defined nanomaterials, e.g., self-assembling peptides, non-peptidic dendrimers, and gold nanoparticles, as antigen-displaying platforms. This review summarizes the recent experimental studies directed to the development of multiple antigen-presenting peptide vaccine systems.

Conjugating recombinant proteins to Pseudomonas aeruginosa ExoProtein A: a strategy for enhancing immunogenicity of malaria vaccine candidates

OpenAIRE

Qian, Feng; Wu, Yimin; Muratova, Olga; Zhou, Hong; Dobrescu, Gelu; Duggan, Peter; Lynn, Lambert; Song, Guanhong; Zhang, Yanling; Reiter, Karine; MacDonald, Nicholas; Narum, David L.; Long, Carole A.; Miller, Louis H.; Saul, Allan

2007-01-01

Conjugation of polysaccharides to carrier proteins has been a successful approach for producing safe and effective vaccines. In an attempt to increase the immunogenicity of two malarial vaccine candidate proteins of Plasmodium falciparum, apical membrane antigen 1 (AMA1) for blood stage vaccines and surface protein 25 (Pfs25) for mosquito stage vaccines, each was chemically conjugated to the mutant, nontoxic Pseudomonas aeruginosa ExoProtein A (rEPA). AMA1 is a large (66 kD) relatively good i...

HIV/AIDS vaccines for Africa: scientific opportunities, challenges and strategies

Science.gov (United States)

Chin'ombe, Nyasha; Ruhanya, Vurayai

2015-01-01

More than decades have already elapsed since human immunodeficiency virus (HIV) was identified as the causative agent of acquired immunodeficiency syndrome (AIDS). The HIV has since spread to all parts of the world with devastating effects. In sub-saharan Africa, the HIV/AIDS epidemic has reached unprecedented proportions. Safe, effective and affordable HIV/AIDS vaccines for Africans are therefore urgently needed to contain this public health problem. Although, there are challenges, there are also scientific opportunities and strategies that can be exploited in the development of HIV/AIDS vaccines for Africa. The recent RV144 Phase III trial in Thailand has demonstrated that it is possible to develop a vaccine that can potentially elicit modest protective immunity against HIV infection. The main objective of this review is to outline the key scientific opportunities, challenges and strategies in HIV/AIDS vaccine development in Africa. PMID:26185576

Development of Novel Vaccines against Enterovirus-71

Science.gov (United States)

Yee, Pinn Tsin Isabel; Poh, Chit Laa

2015-01-01

The hand, foot and mouth disease is caused by a group of Enteroviruses such as Enterovirus 71 (EV-A71) and Coxsackievirus CV-A5, CV-A8, and CV-A16. Mild symptoms of EV-A71 infection in children range from high fever, vomiting, rashes and ulcers in mouth but can produce more severe symptoms such as brainstem and cerebellar encephalitis, leading up to cardiopulmonary failure and death. The lack of vaccines and antiviral drugs against EV-A71 highlights the urgency of developing preventive and treatment agents against EV-A71 to prevent further fatalities. Research groups have developed experimental inactivated vaccines, recombinant Viral Protein 1 (VP1) vaccine and virus-like particles (VLPs). The inactivated EV-A71 vaccine is considered the safest viral vaccine, as there will be no reversion to the infectious wild type strain. The recombinant VP1 vaccine is a cost-effective immunogen, while VLPs contain an arrangement of epitopes that can elicit neutralizing antibodies against the virus. As each type of vaccine has its advantages and disadvantages, increased studies are required in the development of such vaccines, whereby high efficacy, long-lasting immunity, minimal risk to those vaccinated, safe and easy production, low cost, dispensing the need for refrigeration and convenient delivery are the major goals in their design. PMID:26729152

Vaccines: What You Need to Know | NIH MedlinePlus the Magazine

Science.gov (United States)

... two, it is a very safe vaccine. Not vaccinating your children puts them at risk, and that is really ... shame." "For some people, the idea of not vaccinating their child is based on the misperception that the risk ...

Immunology of Gut Mucosal Vaccines

Science.gov (United States)

Pasetti, Marcela F.; Simon, Jakub K.; Sztein, Marcelo B.; Levine, Myron M.

2011-01-01

Summary Understanding the mechanisms underlying the induction of immunity in the gastrointestinal mucosa following oral immunization and the cross-talk between mucosal and systemic immunity should expedite the development of vaccines to diminish the global burden caused by enteric pathogens. Identifying an immunological correlate of protection in the course of field trials of efficacy, animal models (when available), or human challenge studies is also invaluable. In industrialized country populations, live attenuated vaccines (e.g. polio, typhoid, and rotavirus) mimic natural infection and generate robust protective immune responses. In contrast, a major challenge is to understand and overcome the barriers responsible for the diminished immunogenicity and efficacy of the same enteric vaccines in underprivileged populations in developing countries. Success in developing vaccines against some enteric pathogens has heretofore been elusive (e.g. Shigella). Different types of oral vaccines can selectively or inclusively elicit mucosal secretory immunoglobulin A and serum immunoglobulin G antibodies and a variety of cell-mediated immune responses. Areas of research that require acceleration include interaction between the gut innate immune system and the stimulation of adaptive immunity, development of safe yet effective mucosal adjuvants, better understanding of homing to the mucosa of immunologically relevant cells, and elicitation of mucosal immunologic memory. This review dissects the immune responses elicited in humans by enteric vaccines. PMID:21198669

Current status of flavivirus vaccines.

Science.gov (United States)

Barrett, A D

2001-12-01

Although there are approximately 68 flaviviruses recognized, vaccines have been developed to control very few human flavivirus diseases. Licensed live attenuated vaccines have been developed for yellow fever (strain 17D) and Japanese encephalitis (strain SA14-14-2) viruses, and inactivated vaccines have been developed for Japanese encephalitis and tick-borne encephalitis viruses. The yellow fever live attenuated 17D vaccine is one of the most efficacious and safe vaccines developed to date and has been used to immunize more than 300 million people. A number of experimental vaccines are being developed, most notably for dengue. Candidate tetravalent live attenuated dengue vaccines are undergoing clinical trials. Other vaccines are being developed using reverse genetics, DNA vaccines, and recombinant immunogens. In addition, the yellow fever 17D vaccine has been used as a backbone to generate chimeric viruses containing the premembrane and envelope protein genes from other flaviviruses. The "Chimerivax" platform has been used to construct chimeric Japanese encephalitis and dengue viruses that are in different phases of development. Similar strategies are being used by other laboratories.

Are we there yet? Travel vaccinations for Australian children.

Science.gov (United States)

Slonim, Marnie; Starr, Mike; Blashki, Grant

2014-06-01

Australians travel overseas frequently and general practitioners (GPs) are often asked to provide detailed advice on travel vaccinations for children. Planning a safe and effective vaccination schedule is dependent on the context: where and when the family is travelling, the individual child's medical needs and past vaccination history, and if they are visiting family and friends. In this paper we provide an overview of the issues to consider when vaccinating Australian children for overseas travel. We also list the suite of common travel vaccinations and discuss some clinical scenarios that are likely to present in Australian general practice. Australians love to travel overseas and, increasingly, GPs are asked by patients to provide detailed advice on travel vaccinations for their children. Decisions regarding vaccinations for travelling children can be complex and the advice often differs from that provided for adults. Children differ from adults in their vulnerability to illnesses and side effects of medications. These differences, as well as their status regarding routine childhood vaccinations, all need to be taken into account. As with adults, it is important to consider the location and duration of travel and time until departure. The age of the child is also important and there may be a case for accelerating the routine childhood vaccinations in some children. The aim of this paper is to provide a clear and simple outline of the vaccination recommendations for children travelling overseas from Australia.

Edible vaccines: Current status and future

Directory of Open Access Journals (Sweden)

Lal P

2007-01-01

Full Text Available Edible vaccines hold great promise as a cost-effective, easy-to-administer, easy-to-store, fail-safe and socioculturally readily acceptable vaccine delivery system, especially for the poor developing countries. It involves introduction of selected desired genes into plants and then inducing these altered plants to manufacture the encoded proteins. Introduced as a concept about a decade ago, it has become a reality today. A variety of delivery systems have been developed. Initially thought to be useful only for preventing infectious diseases, it has also found application in prevention of autoimmune diseases, birth control, cancer therapy, etc. Edible vaccines are currently being developed for a number of human and animal diseases. There is growing acceptance of transgenic crops in both industrial and developing countries. Resistance to genetically modified foods may affect the future of edible vaccines. They have passed the major hurdles in the path of an emerging vaccine technology. Various technical obstacles, regulatory and non-scientific challenges, though all seem surmountable, need to be overcome. This review attempts to discuss the current status and future of this new preventive modality.

Leishmania infantum HSP70-II null mutant as candidate vaccine against leishmaniasis: a preliminary evaluation

Directory of Open Access Journals (Sweden)

Fresno Manuel

2011-07-01

Full Text Available Abstract Background Visceral leishmaniasis is the most severe form of leishmaniasis and no effective vaccine exists. The use of live attenuated vaccines is emerging as a promising vaccination strategy. Results In this study, we tested the ability of a Leishmania infantum deletion mutant, lacking both HSP70-II alleles (ΔHSP70-II, to provide protection against Leishmania infection in the L. major-BALB/c infection model. Administration of the mutant line by either intraperitoneal, intravenous or subcutaneous route invariably leads to the production of high levels of NO and the development in mice of type 1 immune responses, as determined by analysis of anti-Leishmania IgG subclasses. In addition, we have shown that ΔHSP70-II would be a safe live vaccine as immunodeficient SCID mice, and hamsters (Mesocricetus auratus, infected with mutant parasites did not develop any sign of pathology. Conclusions The results suggest that the ΔHSP70-II mutant is a promising and safe vaccine, but further studies in more appropriate animal models (hamsters and dogs are needed to appraise whether this attenuate mutant would be useful as vaccine against visceral leishmaniasis.

Estimating the cost-effectiveness profile of a universal vaccination programme with a nine-valent HPV vaccine in Austria.

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Boiron, L; Joura, E; Largeron, N; Prager, B; Uhart, M

2016-04-16

HPV is a major cancer-causing factor in both sexes in the cervix, vulva, vagina, anus, penis, oropharynx as well as the causal factor in other diseases such as genital warts and recurrent respiratory papillomatis. In the context of the arrival of a nonavalent HPV vaccine (6/11/16/18/31/33/45/52/58), this analysis aims to estimate the public health impact and the incremental cost-effectiveness of a universal (girls and boys) vaccination program with a nonavalent HPV vaccine as compared to the current universal vaccination program with a quadrivalent HPV vaccine (6/11/16/18), in Austria. A dynamic transmission model including a wide range of health and cost outcomes related to cervical, anal, vulvar, vaginal diseases and genital warts was calibrated to Austrian epidemiological data. The clinical impact due to the 5 new types was included for cervical and anal diseases outcomes only. In the base case, a two-dose schedule, lifelong vaccine type-specific protection and a vaccination coverage rate of 60% and 40% for girls and boys respectively for the 9-year old cohorts were assumed. A cost-effectiveness threshold of €30,000/QALY-gained was considered. Universal vaccination with the nonavalent vaccine was shown to reduce the incidence of HPV16/18/31/33/45/52/58 -related cervical cancer by 92%, the related CIN2/3 cases by 96% and anal cancer by 83% and 76% respectively in females and males after 100 years, relative to 75%, 76%, 80% and 74% with the quadrivalent vaccine, respectively. Furthermore, the nonavalent vaccine was projected to prevent an additional 14,893 cases of CIN2/3 and 2544 cases of cervical cancer, over 100 years. Depending on the vaccine price, the strategy was shown to be from cost-saving to cost-effective. The present evaluation showed that vaccinating 60% of girls and 40% of boys aged 9 in Austria with a 9-valent vaccine will substantially reduce the incidence of cervical cancer, CIN and anal cancer compared to the existing strategy. The vaccination

Meningococcal group B vaccines.

Science.gov (United States)

Findlow, Jamie

2013-06-01

Meningococcal disease remains a devastating and feared infection with a significant morbidity and mortality profile. The successful impact of meningococcal capsular group C glyconconjugate vaccines introduced into the UK infant immunization schedule in 1999, has resulted in >80% of disease now being attributable to meningococcal capsular group B (MenB). MenB glyconconjugate vaccines are not immunogenic and hence, vaccine design has focused on sub-capsular antigens. Recently, a four component vaccine to combat MenB disease (4CMenB) has progressed through clinical development and was approved by the European Medicines Agency at the end of 2012. This vaccine has proven safe and immunogenic and has been predicted to provide protection against ~73% of the MenB disease from England and Wales. Recommendation/implementation of the vaccine into the UK infant schedule is currently being evaluated. 4CMenB has the potential to provide protection against a significant proportion of MenB disease in the UK which is currently unpreventable.

What a rheumatologist needs to know about yellow fever vaccine.

Science.gov (United States)

Oliveira, Ana Cristina Vanderley; Mota, Licia Maria Henrique da; Santos-Neto, Leopoldo Luiz Dos; Tauil, Pedro Luiz

2013-04-01

Patients with rheumatic diseases are more susceptible to infection, due to the underlying disease itself or to its treatment. The rheumatologist should prevent infections in those patients, vaccination being one preventive measure to be adopted. Yellow fever is one of such infectious diseases that can be avoided.The yellow fever vaccine is safe and effective for the general population, but, being an attenuated live virus vaccine, it should be avoided whenever possible in rheumatic patients on immunosuppressive drugs. Considering that yellow fever is endemic in a large area of Brazil, and that vaccination against that disease is indicated for those living in such area or travelling there, rheumatologists need to know that disease, as well as the indications for the yellow fever vaccine and contraindications to it. Our paper was aimed at highlighting the major aspects rheumatologists need to know about the yellow fever vaccine to decide about its indication or contraindication in specific situations. 2013 Elsevier Editora Ltda. All rights reserved.

Efficacy and effectiveness of an rVSV-vectored vaccine expressing Ebola surface glycoprotein: interim results from the Guinea ring vaccination cluster-randomised trial.

Science.gov (United States)

Henao-Restrepo, Ana Maria; Longini, Ira M; Egger, Matthias; Dean, Natalie E; Edmunds, W John; Camacho, Anton; Carroll, Miles W; Doumbia, Moussa; Draguez, Bertrand; Duraffour, Sophie; Enwere, Godwin; Grais, Rebecca; Gunther, Stephan; Hossmann, Stefanie; Kondé, Mandy Kader; Kone, Souleymane; Kuisma, Eeva; Levine, Myron M; Mandal, Sema; Norheim, Gunnstein; Riveros, Ximena; Soumah, Aboubacar; Trelle, Sven; Vicari, Andrea S; Watson, Conall H; Kéïta, Sakoba; Kieny, Marie Paule; Røttingen, John-Arne

2015-08-29

these clusters (4123 people) were randomly assigned to immediate vaccination with rVSV-ZEBOV, and 42 clusters (3528 people) were randomly assigned to delayed vaccination with rVSV-ZEBOV. In the immediate vaccination group, there were no cases of Ebola virus disease with symptom onset at least 10 days after randomisation, whereas in the delayed vaccination group there were 16 cases of Ebola virus disease from seven clusters, showing a vaccine efficacy of 100% (95% CI 74·7-100·0; p=0·0036). No new cases of Ebola virus disease were diagnosed in vaccinees from the immediate or delayed groups from 6 days post-vaccination. At the cluster level, with the inclusion of all eligible adults, vaccine effectiveness was 75·1% (95% CI -7·1 to 94·2; p=0·1791), and 76·3% (95% CI -15·5 to 95·1; p=0·3351) with the inclusion of everyone (eligible or not eligible for vaccination). 43 serious adverse events were reported; one serious adverse event was judged to be causally related to vaccination (a febrile episode in a vaccinated participant, which resolved without sequelae). Assessment of serious adverse events is ongoing. The results of this interim analysis indicate that rVSV-ZEBOV might be highly efficacious and safe in preventing Ebola virus disease, and is most likely effective at the population level when delivered during an Ebola virus disease outbreak via a ring vaccination strategy. WHO, with support from the Wellcome Trust (UK); Médecins Sans Frontières; the Norwegian Ministry of Foreign Affairs through the Research Council of Norway; and the Canadian Government through the Public Health Agency of Canada, Canadian Institutes of Health Research, International Development Research Centre, and Department of Foreign Affairs, Trade and Development. Copyright © 2015 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd.. All rights reserved.

Rotavirus vaccines: safety, efficacy and public health impact.

Science.gov (United States)

Gray, J

2011-09-01

Rotaviruses are the cause of acute gastroenteritis, and disease is widespread amongst infants and young children throughout the world. Also, rotavirus is associated with significant mortality in developing countries with more than 500 000 children dying each year as a result of the severe dehydration associated with rotavirus disease. Efforts have been ongoing for more than 30 years to develop a safe and effective rotavirus vaccine. Currently, two vaccines, RotaRix and RotaTeq, have been licensed for use in many countries throughout the world following comprehensive safety and efficiency trials. Monitoring their effectiveness after licensure has confirmed that their incorporation into early childhood vaccination schedules can significantly prevent severe rotavirus diarrhoea, which would have resulted in hospitalizations, emergency room visits or increased diarrhoea-related mortality. Although the efficacy of both vaccines is lower at approximately 40-59% in developing countries, their use could significantly reduce the mortality associated with rotavirus disease that is concentrated in these countries. © 2011 The Association for the Publication of the Journal of Internal Medicine.

Immunogenicity and safety of a live attenuated varicella vaccine in ...

African Journals Online (AJOL)

children were vaccinated, of whom 189 (44,5%) completed the study. ... varicella vaccination.. Results. The vaccine was safe and well tolerated. No local symptoms were ... of varicella (e.g. encephalitis, pneumonia, scars); inhibition of the spread of the .... intestinal disorders, respiratory infections, measles and conjunctivitis) ...

Effectiveness of Monovalent and Pentavalent Rotavirus Vaccines in Guatemala.

Science.gov (United States)

Gastañaduy, Paul A; Contreras-Roldán, Ingrid; Bernart, Chris; López, Beatriz; Benoit, Stephen R; Xuya, Marvin; Muñoz, Fredy; Desai, Rishi; Quaye, Osbourne; Tam, Ka Ian; Evans-Bowen, Diana K; Parashar, Umesh D; Patel, Manish; McCracken, John P

2016-05-01

Concerns remain about lower effectiveness and waning immunity of rotavirus vaccines in resource-poor populations. We assessed vaccine effectiveness against rotavirus in Guatemala, where both the monovalent (RV1; 2-dose series) and pentavalent (RV5; 3-dose series) vaccines were introduced in 2010. A case-control evaluation was conducted in 4 hospitals from January 2012 to August 2013. Vaccine status was compared between case patients (children with laboratory-confirmed rotavirus diarrhea) and 2 sets of controls: nondiarrhea "hospital" controls (matched by birth date and site) and nonrotavirus "test-negative" diarrhea controls (adjusted for age, birth month/year, and site). Vaccine effectiveness ([1 - odds ratio of vaccination] × 100%) was computed using logistic regression models. We evaluated 213 case patients, 657 hospital controls, and 334 test-negative controls. Effectiveness of 2-3 doses of a rotavirus vaccine against rotavirus requiring emergency department visit or hospitalization was 74% (95% confidence interval [CI], 58%-84%) with hospital controls, and 52% (95% CI, 26%-69%) with test-negative controls. Using hospital controls, no significant difference in effectiveness was observed between infants 6-11 months (74% [95% CI, 18%-92%]) and children ≥12 months of age (71% [95% CI, 44%-85%]) (P= .85), nor between complete courses of RV1 (63% [95% CI, 23%-82%]) and RV5 (69% [95% CI, 29%-87%]) (P= .96). An uncommon G12P[8] strain, partially heterotypic to strains in both vaccines, was identified in 89% of cases. RV1 and RV5 were similarly effective against severe rotavirus diarrhea caused by a heterotypic strain in Guatemala. This supports broader implementation of rotavirus vaccination in low-income countries where >90% global deaths from rotavirus occur. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Successful administration of measles-rubella-mumps vaccine by graded challenge in a case with anaphylaxis after prior vaccination.

Science.gov (United States)

Tuncel, Tuba; Sancakli, Ozlem; Ozdogru, Ece

2017-04-01

Egg allergy is one of the most common food allergies during childhood along with cow's milk allergy. The measles-mumpsrubella (MMR) vaccine is included in the pediatric immunization schedule and contains egg protein. The currently accepted opinion is that the MMR vaccination should be done in a single dose under medical observation in patients with egg allergy. Although it is reported that the MMR vaccine is safe for that patients, there are some patients who developed anaphylaxis. Generally, the development of anaphylaxis after the previous vaccination is reported as a contraindication. We present a successful administration of MMR vaccine by gradually increased doses for a patient who developed anaphylaxis after the previous vaccination. Sociedad Argentina de Pediatría.

The future of HIV vaccine research and the role of the Global HIV Vaccine Enterprise.

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Voronin, Yegor; Manrique, Amapola; Bernstein, Alan

2010-09-01

This review covers the role of the Global HIV Vaccine Enterprise (the Enterprise), an alliance of independent organizations committed to development of a safe and effective HIV vaccine. It discusses the history, impact on the field, and future directions and initiatives of the alliance in the context of recent progress in HIV vaccine research and development. Significant progress has been made in the field since the release of the 2005 Scientific Strategic Plan (the Plan) of the Enterprise. Over the last year, the Enterprise embarked on an impact assessment of the 2005 Plan and the development of the 2010 Plan. Enterprise Working Groups identified key priorities in the field, several of which are discussed in this review, including changing the nature, purpose and process of clinical trials, increasing and facilitating data sharing, and optimizing existing and mobilizing new resources. This time is an important moment in HIV vaccine research. New clinical trial and laboratory results have created new opportunities to advance the search for an HIV vaccine and reinvigorated the field. The Enterprise will publish its 2010 Plan this year, providing a framework for setting new priorities and directions and encouraging new and existing partners to embark on a shared scientific agenda.

Occurrence of Autoimmune Diseases Related to the Vaccine against Yellow Fever

Directory of Open Access Journals (Sweden)

Ana Cristina Vanderley Oliveira

2014-01-01

Full Text Available Yellow fever is an infectious disease, endemic in South America and Africa. This is a potentially serious illness, with lethality between 5 and 40% of cases. The most effective preventive vaccine is constituted by the attenuated virus strain 17D, developed in 1937. It is considered safe and effective, conferring protection in more than 90% in 10 years. Adverse effects are known as mild reactions (allergies, transaminases transient elevation, fever, headache and severe (visceral and neurotropic disease related to vaccine. However, little is known about its potential to induce autoimmune responses. This systematic review aims to identify the occurrence of autoinflammatory diseases related to 17D vaccine administration. Six studies were identified describing 13 possible cases. The diseases were Guillain-Barré syndrome, multiple sclerosis, multiple points evanescent syndrome, acute disseminated encephalomyelitis, autoimmune hepatitis, and Kawasaki disease. The data suggest that 17D vaccination may play a role in the mechanism of loss of self-tolerance.

Subdeltoid/subacromial bursitis associated with influenza vaccination.

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Cook, Ian F

2014-01-01

A 76-year-old male presented with subacromial/subdeltoid bursitis following influenza vaccine administration into the left deltoid muscle. This shoulder injury related to vaccine administration (SIRVA) could have been prevented by the use of a safe, evidence based protocol for the intramuscular injection of the deltoid muscle.

"It just forces hardship": impacts of government financial penalties on non-vaccinating parents.

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Helps, Catherine; Leask, Julie; Barclay, Lesley

2018-01-22

Despite strong evidence confirming vaccination is safe and effective, some parents choose not to vaccinate their children. In 2016, the Australian Government introduced legislation strengthening links between vaccination compliance and some government payments. We interviewed thirty-one non-vaccinating parents about the impacts of this policy. Data analysis produced three key themes: 'questioning policy integrity', 'minimising impact' and 'holding my ground'. Affected parents offset reduced income by removing children from early childhood learning, reducing work commitments, moving residence to reduce living costs and accessing informal childcare arrangements. Parents reported a greater commitment to their decision not to vaccinate and an increased desire to maintain control over health choices for their children including an unprecedented willingness to become involved in protest action. Our study identifies why financial penalties have not been an effective policy measure for this sample of non-vaccinating parents, an understanding which may assist in the development of future legislation.

Cost-effectiveness analysis of vaccinations and decision makings on vaccination programmes in Hong Kong: A systematic review.

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Wong, Carlos K H; Liao, Qiuyan; Guo, Vivian Y W; Xin, Yiqiao; Lam, Cindy L K

2017-05-31

To describe and systematically review the modelling and reporting of cost-effectiveness analysis of vaccination in Hong Kong, and to identify areas for quality enhancement in future cost-effectiveness analyses. We conducted a comprehensive and systematic review of cost-effectiveness studies related to vaccination and government immunisation programmes in Hong Kong published from 1990 to 2015, through database search of Pubmed, Web of Science, Embase, and OVID Medline. Methodological quality of selected studies was assessed using Consolidated Health Economic Evaluation Reporting Standards checklist (CHEERS). Decision making of vaccination was obtained from Scientific Committee on Vaccine Preventable Diseases (SCVPD) and Department of Health in Hong Kong. Nine eligible studies reporting twelve comparative cost-effectiveness comparisons of vaccination programme for influenza (n=2), pneumococcal disease (n=3), influenza plus pneumococcal disease (n=1), chickenpox (n=2), Haemophilus influenzae b (n=1), hepatitis A (n=1), cervical cancer (n=1) and rotavirus (n=1) were identified. Ten comparisons (83.3%) calculated the incremental cost-effectiveness ratio (ICER) of a vaccination strategy versus status quo as outcomes in terms of cost in USD per life-years, cost per quality-adjusted life-years, or cost per disability-adjusted life-years. Among those 10 comparisons in base-case scenario, 4 evaluated interventions were cost-saving relative to status quo while the ICER estimates in 3 of the 6 remaining comparisons were far below commonly accepted threshold and WHO willingness-to-pay threshold, suggestive of very cost-effective. Seven studies were of good quality based on the CHEERS checklist; one was of moderate quality; and one was of excellent quality. The common methodological problems were characterisation of heterogeneity and reporting of study parameters. There was a paucity of cost-effectiveness models evaluating vaccination targeted to the Hong Kong population. All

Development of an epitope-based HIV-1 vaccine strategy from HIV-1 lipopeptide to dendritic-based vaccines.

Science.gov (United States)

Surenaud, Mathieu; Lacabaratz, Christine; Zurawski, Gérard; Lévy, Yves; Lelièvre, Jean-Daniel

2017-10-01

Development of a safe, effective and globally affordable Human Immunodeficiency Virus strain 1 (HIV-1) vaccine offers the best hope for future control of the HIV-1 pandemic. However, with the exception of the recent RV144 trial, which elicited a modest level of protection against infection, no vaccine candidate has shown efficacy in preventing HIV-1 infection or in controlling virus replication in humans. There is also a great need for a successful immunotherapeutic vaccine since combination antiretroviral therapy (cART) does not eliminate the reservoir of HIV-infected cells. But to date, no vaccine candidate has proven to significantly alter the natural history of an individual with HIV-1 infection. Areas covered: For over 25 years, the ANRS (France Recherche Nord&Sud Sida-HIV hépatites) has been committed to an original program combining basic science and clinical research developing an epitope-based vaccine strategy to induce a multiepitopic cellular response against HIV-1. This review describes the evolution of concepts, based on strategies using HIV-1 lipopeptides towards the use of dendritic cell (DC) manipulation. Expert commentary: Understanding the crucial role of DCs in immune responses allowed moving from the non-specific administration of HIV-1 sequences with lipopeptides to DC-based vaccines. These DC-targeting strategies should improve HIV-1 vaccine efficacy.

Cost-effectiveness of norovirus vaccination in children in Peru.

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Mirelman, Andrew J; Ballard, Sarah Blythe; Saito, Mayuko; Kosek, Margaret N; Gilman, Robert H

2015-06-17

With candidate norovirus (NV) vaccines in a rapid phase of development, assessment of the potential economic value of vaccine implementation will be necessary to aid health officials in vaccine implementation decisions. To date, no evaluations have been performed to evaluate the benefit of adopting NV vaccines for use in the childhood immunization programs of low- and middle-income countries. We used a Markov decision model to evaluate the cost-effectiveness of adding a two-dose NV vaccine to Peru's routine childhood immunization schedule using two recent estimates of NV incidence, one for a peri-urban region and one for a jungle region of the country. Using the peri-urban NV incidence estimate, the annual cost of vaccination would be $13.0 million, offset by $2.6 million in treatment savings. Overall, this would result in 473 total DALYs averted; 526,245 diarrhea cases averted;153,735 outpatient visits averted; and 414 hospitalizations averted between birth and the fifth year of life. The incremental cost-effectiveness ratio would be $21,415 per DALY averted; $19.86 per diarrhea case; $68.23 per outpatient visit; and $26,298 per hospitalization. Using the higher jungle NV incidence rates provided a lower cost per DALY of $10,135. The incremental cost per DALY with per-urban NV incidence is greater than three times the 2012 GDP per capita of Peru but the estimate drops below this threshold using the incidence from the jungle setting. In addition to the impact of incidence, sensitivity analysis showed that vaccine price and efficacy play a strong role in determining the level of cost-effectiveness. The introduction of a NV vaccine would prevent many healthcare outcomes in the Peru and potentially be cost-effective in scenarios with high NV incidence. The vaccine cost-effectiveness model could also be applied to the evaluation of NV vaccine cost-effectiveness in other countries. In resource-poor settings, where NV incidence rates are expected to be higher. Published

Tipping the Proteome with Gene-Based Vaccines: Weighing in on the Role of Nano materials

International Nuclear Information System (INIS)

Flores, K.J.; Craig, M.; Smith, J.J.; DeLong, R.K.; Wanekaya, A.; Dong, L.

2012-01-01

Since the first generation of DNA vaccines was introduced in 1988, remarkable improvements have been made to improve their efficacy and immunogenicity. Although human clinical trials have shown that delivery of DNA vaccines is well tolerated and safe, the potency of these vaccines in humans is somewhat less than optimal. The development of a gene-based vaccine that was effective enough to be approved for clinical use in humans would be one of, if not the most important, advance in vaccines to date. This paper highlights the literature relating to gene-based vaccines, specifically DNA vaccines, and suggests possible approaches to boost their performance. In addition, we explore the idea that combining RNA and nano materials may hold the key to successful gene-based vaccines for prevention and treatment of disease

42 CFR 71.3 - Designation of yellow fever vaccination centers; Validation stamps.

Science.gov (United States)

2010-10-01

... safe, potent, and pure yellow fever vaccine. Medical facilities of Federal agencies are authorized to obtain yellow fever vaccine without being designated as a yellow fever vaccination center by the Director..., storage, and administration of yellow fever vaccine. If a designated center fails to comply with such...

Impact of imitation processes on the effectiveness of ring vaccination.

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Wells, Chad R; Tchuenche, Jean M; Meyers, Lauren Ancel; Galvani, Alison P; Bauch, Chris T

2011-11-01

Ring vaccination can be a highly effective control strategy for an emerging disease or in the final phase of disease eradication, as witnessed in the eradication of smallpox. However, the impact of behavioural dynamics on the effectiveness of ring vaccination has not been explored in mathematical models. Here, we analyze a series of stochastic models of voluntary ring vaccination. Contacts of an index case base vaccinating decisions on their own individual payoffs to vaccinate or not vaccinate, and they can also imitate the behaviour of other contacts of the index case. We find that including imitation changes the probability of containment through ring vaccination considerably. Imitation can cause a strong majority of contacts to choose vaccination in some cases, or to choose non-vaccination in other cases-even when the equivalent solution under perfectly rational (non-imitative) behaviour yields mixed choices. Moreover, imitation processes can result in very different outcomes in different stochastic realizations sampled from the same parameter distributions, by magnifying moderate tendencies toward one behaviour or the other: in some realizations, imitation causes a strong majority of contacts not to vaccinate, while in others, imitation promotes vaccination and reduces the number of secondary infections. Hence, the effectiveness of ring vaccination can depend significantly and unpredictably on imitation processes. Therefore, our results suggest that risk communication efforts should be initiated early in an outbreak when ring vaccination is to be applied, especially among subpopulations that are heavily influenced by peer opinions.

The cost-effectiveness of male HPV vaccination in the United States.

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Chesson, Harrell W; Ekwueme, Donatus U; Saraiya, Mona; Dunne, Eileen F; Markowitz, Lauri E

2011-10-26

The objective of this study was to estimate the cost-effectiveness of adding human papillomavirus (HPV) vaccination of 12-year-old males to a female-only vaccination program for ages 12-26 years in the United States. We used a simplified model of HPV transmission to estimate the reduction in the health and economic burden of HPV-associated diseases in males and females as a result of HPV vaccination. Estimates of the incidence, cost-per-case, and quality-of-life impact of HPV-associated health outcomes were based on the literature. The HPV-associated outcomes included were: cervical intraepithelial neoplasia (CIN); genital warts; juvenile-onset recurrent respiratory papillomatosis (RRP); and cervical, vaginal, vulvar, anal, oropharyngeal, and penile cancers. The cost-effectiveness of male vaccination depended on vaccine coverage of females. When including all HPV-associated outcomes in the analysis, the incremental cost per quality-adjusted life year (QALY) gained by adding male vaccination to a female-only vaccination program was $23,600 in the lower female coverage scenario (20% coverage at age 12 years) and $184,300 in the higher female coverage scenario (75% coverage at age 12 years). The cost-effectiveness of male vaccination appeared less favorable when compared to a strategy of increased female vaccination coverage. For example, we found that increasing coverage of 12-year-old girls would be more cost-effective than adding male vaccination even if the increased female vaccination strategy incurred program costs of $350 per additional girl vaccinated. HPV vaccination of 12-year-old males might potentially be cost-effective, particularly if female HPV vaccination coverage is low and if all potential health benefits of HPV vaccination are included in the analysis. However, increasing female coverage could be a more efficient strategy than male vaccination for reducing the overall health burden of HPV in the population. Published by Elsevier Ltd.

Beliefs, behaviors and HPV vaccine: correcting the myths and the misinformation.

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Zimet, Gregory D; Rosberger, Zeev; Fisher, William A; Perez, Samara; Stupiansky, Nathan W

2013-11-01

Human papillomavirus (HPV) vaccine uptake in many countries has been sub-optimal. We examine several issues associated with non-vaccination that have received particular attention, including fears about sexual risk compensation, concerns about vaccine safety, inadequate vaccination recommendations by health care providers (HCPs), and distrust due to the perceived "newness" of HPV vaccines. Selective review of behavioral and social science literature on HPV vaccine attitudes and uptake. There is no evidence of post-vaccination sexual risk compensation, HPV vaccines are quite safe, and they can no longer be considered "new". Nonetheless, research findings point to these issues and, most importantly, to the failure of HCPs to adequately recommend HPV vaccine as major drivers of non-vaccination. Most fears related to HPV vaccine are more related to myth than reality. In the absence of major health policy initiatives, such as those implemented in Canada, the U.K., and Australia, a multi-level, multi-faceted approach will be required to achieve high rates of HPV vaccination. It will be essential to focus on the education of HCPs regarding indications for HPV vaccination and approaches to communicating most effectively with parents and patients about the safety and benefits of vaccination and the risks associated with non-vaccination. Copyright © 2013 Elsevier Inc. All rights reserved.

Dynamic modeling of cost-effectiveness of rotavirus vaccination, Kazakhstan.

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Freiesleben de Blasio, Birgitte; Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

2014-01-01

The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children vaccine cost at vaccination program costs would be entirely offset. To further evaluate efficacy of a vaccine program, benefits of indirect protection conferred by vaccination warrant further study.

Maternal vaccination to prevent pertussis in infants

African Journals Online (AJOL)

2016-09-09

Sep 9, 2016 ... that maternal immunisation with the Tdap (tetanus, diphtheria and acellular pertussis) vaccine is safe. Indeed, maternal vaccination is now recommended to prevent pertussis infection in vulnerable young infants. In the USA and UK, the immunisation of pregnant women with a Tdap or dTaP/IPV (diphtheria, ...

Cost-effectiveness analysis of vaccinating children in Malawi with RTS,S vaccines in comparison with long-lasting insecticide-treated nets.

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Seo, Mikyung Kelly; Baker, Peter; Ngo, Karen Ngoc-Lan

2014-02-24

New RTS,S malaria vaccines may soon be licensed, yet its cost-effectiveness is unknown. Before the widespread introduction of RTS,S vaccines, cost-effectiveness studies are needed to help inform governments in resource-poor settings about how best to prioritize between the new vaccine and existing malaria interventions. A Markov model simulated malaria progression in a hypothetical Malawian birth cohort. Parameters were based on published data. Three strategies were compared: no intervention, vaccination at one year, and long-lasting, insecticide-treated nets (LLINs) at birth. Both health service and societal perspectives were explored. Health outcomes were measured in disability-adjusted life years (DALYs) averted and costed in 2012 US$. Incremental cost-effectiveness ratios (ICERs) were calculated and extensive sensitivity analyses were conducted. Three times GDP per capita ($1,095) per DALY averted was used for a cost-effectiveness threshold, whilst one times GDP ($365) was considered 'very cost-effective'. From a societal perspective the vaccine strategy was dominant. It averted 0.11 more DALYs than LLINs and 0.372 more DALYs than the no intervention strategy per person, while costing $10.04 less than LLINs and $59.74 less than no intervention. From a health service perspective the vaccine's ICER was $145.03 per DALY averted, and thus can be considered very cost-effective. The results were robust to changes in all variables except the vaccine and LLINs' duration of efficacy. Vaccines remained cost-effective even at the lowest assumed efficacy levels of 49.6% (mild malaria) and 14.2% (severe malaria), and the highest price of $15. However, from a societal perspective, if the vaccine duration efficacy was set below 2.69 years or the LLIN duration of efficacy was greater than 4.24 years then LLINs became the more cost-effective strategy. The results showed that vaccinating Malawian children with RTS,S vaccines was very cost-effective from both a societal and a

Dynamic Modeling of Cost-effectiveness of Rotavirus Vaccination, Kazakhstan

Science.gov (United States)

Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

2014-01-01

The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children <5 years of age. Indirect protection accounted for 40% and 60% reduction in severe and mild rotavirus gastroenteritis, respectively. Cost per life year gained was US $18,044 from a societal perspective and US $23,892 from a health care perspective. Comparing the 2 key parameters of cost-effectiveness, mortality rates and vaccine cost at vaccination program costs would be entirely offset. To further evaluate efficacy of a vaccine program, benefits of indirect protection conferred by vaccination warrant further study. PMID:24378188

Successful adjuvant-free vaccination of BALB/c mice with mutated amyloid β peptides

Directory of Open Access Journals (Sweden)

Wahi Monika M

2008-02-01

Full Text Available Abstract Background A recent human clinical trial of an Alzheimer's disease (AD vaccine using amyloid beta (Aβ 1–42 plus QS-21 adjuvant produced some positive results, but was halted due to meningoencephalitis in some participants. The development of a vaccine with mutant Aβ peptides that avoids the use of an adjuvant may result in an effective and safer human vaccine. Results All peptides tested showed high antibody responses, were long-lasting, and demonstrated good memory response. Epitope mapping indicated that peptide mutation did not lead to epitope switching. Mutant peptides induced different inflammation responses as evidenced by cytokine profiles. Ig isotyping indicated that adjuvant-free vaccination with peptides drove an adequate Th2 response. All anti-sera from vaccinated mice cross-reacted with human Aβ in APP/PS1 transgenic mouse brain tissue. Conclusion Our study demonstrated that an adjuvant-free vaccine with different Aβ peptides can be an effective and safe vaccination approach against AD. This study represents the first report of adjuvant-free vaccines utilizing Aβ peptides carrying diverse mutations in the T-cell epitope. These largely positive results provide encouragement for the future of the development of human vaccinations for AD.

Cost-Effectiveness of Rotavirus Vaccination in France-Accounting for Indirect Protection.

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Yamin, Dan; Atkins, Katherine E; Remy, Vanessa; Galvani, Alison P

Vaccination against rotavirus has shown great potential for reducing the primary cause of severe childhood gastroenteritis. Previous economic evaluations of rotavirus vaccination in France have not modeled the potential impact of vaccines on disease burden via reduced transmission. To determine the cost-effectiveness of the introduction of pentavalent rotavirus vaccination into the French infant vaccination schedule. We developed an age-structured model of rotavirus transmission calibrated to 6 years of French gastroenteritis incidence and vaccine clinical trial data. We evaluated the cost-effectiveness of pentavalent rotavirus vaccination considering that 75% of infants would receive the three-dose vaccine course. Our model predicts that rotavirus vaccination will decrease rotavirus gastroenteritis incidence and associated clinical outcomes in vaccinated and unvaccinated individuals, delay the seasonal peak of infection, and increase the age of infection. From the societal perspective, our base-case scenario predicts that vaccination coverage would be cost-effective at €115 or €135 per vaccine course at €28,500 and €39,500/quality-adjusted life-year (QALY) gained, respectively, and suggests that almost 95% of the financial benefits will be recouped within the first 5 years following vaccination implementation. From the third-party payer perspective, incremental cost-effectiveness ratios ranged from €12,500 to €20,000/QALY, respectively. Our uncertainty analysis suggests that findings were sensitive to various assumptions including the number of hospitalizations, outpatient visits, and the extent of QALY losses per rotavirus episode. Introducing pentavalent rotavirus vaccination into the French infant vaccination schedule would significantly reduce the burden of rotavirus disease in children, and could be cost-effective under plausible conditions. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by

Estimating long-term clinical effectiveness and cost-effectiveness of HPV 16/18 vaccine in China.

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Zhang, Qian; Liu, Yi-Jun; Hu, Shang-Ying; Zhao, Fang-Hui

2016-11-04

Human papillomavirus (HPV) 16 and 18 are the two most common HPV oncogenic types that can be prevented by vaccination. This study aimed at assessing the cost-effectiveness of 3 doses of the bivalent HPV vaccine in rural and urban settings in China. A Markov model was adapted to reflect the lifetime of a modelled 100,000 12-year-old girls cohort in rural and urban settings in China. Input parameters were obtained from published literature, official reports and a two-round expert review panel. Clinical and economic outcomes of vaccination at age 12 with screening was compared to screening only. In the base case analysis, a 3 % discount rate, the vaccine cost of 247 CNY (US$ 39, PAHO vaccine cost in 2013), two rounds of screening in a life time and 70 % coverage for both screening and vaccination were used. One-way, two-way and probabilistic sensitivity analyses were performed. We used different thresholds of cost-effectiveness to reflect the diversity of economic development in China. Vaccination in addition to screening could prevent 60 % more cervical cancer cases and deaths than screening only. The incremental cost effectiveness ratio varied largely when changing cost of vaccination and discount in one way analysis. Vaccination was very cost-effective when the vaccine cost ranged 87-630 CNY (US$ 13.8-100) in rural and 87-750 CNY (US$ 13.8-119) in urban; and remained cost-effective when the vaccine cost ranged 630-1,700 CNY (US$ 100-270) in rural and 750-1,900 CNY (US$ 119-302) in urban in two way analysis. Probabilistic sensitivity analyses showed that model results were robust. In both rural and urban, the vaccination cost and discounting are important factors determining the cost-effectiveness of HPV vaccination; policy makers in China should take these into account when making a decision on the introduction of HPV vaccine. In areas with a high burden of cervical cancer and limited screening activities, HPV vaccination should be prioritized. However, the vaccine

New vaccines against otitis media: projected benefits and cost-effectiveness.

Science.gov (United States)

O'Brien, Megan A; Prosser, Lisa A; Paradise, Jack L; Ray, G Thomas; Kulldorff, Martin; Kurs-Lasky, Marcia; Hinrichsen, Virginia L; Mehta, Jyotsna; Colborn, D Kathleen; Lieu, Tracy A

2009-06-01

New vaccines that offer protection against otitis media caused by nontypeable Haemophilus influenzae and by Moraxella catarrhalis are under development. However, the potential health benefits and economic effects of such candidate vaccines have not been systematically assessed. We created a computerized model to compare the projected benefits and costs of (1) the currently available 7-valent pneumococcal conjugate vaccine, (2) a candidate pneumococcal-nontypeable H influenzae vaccine that has been tested in Europe, (3) a hypothetical pneumococcal-nontypeable H influenzae-Moraxella vaccine, and (4) no vaccination. The clinical probabilities of acute otitis media and of otitis media with effusion were generated from multivariate analyses of data from 2 large health maintenance organizations and from the Pittsburgh Child Development/Otitis Media Study cohort. Other probabilities, costs, and quality-of-life values were derived from published and unpublished sources. The base-case analysis assumed vaccine dose costs of $65 for the 7-valent pneumococcal conjugate vaccine, $100 for the pneumococcal-nontypeable H influenzae vaccine, and $125 for the pneumococcal-nontypeable H influenzae-Moraxella vaccine. With no vaccination, we projected that 13.7 million episodes of acute otitis media would occur annually in US children aged 0 to 4 years, at an annual cost of $3.8 billion. The 7-valent pneumococcal conjugate vaccine was projected to prevent 878,000 acute otitis media episodes, or 6.4% of those that would occur with no vaccination; the corresponding value for the pneumococcal-nontypeable H influenzae vaccine was 3.7 million (27%) and for the pneumococcal-nontypeable H influenzae-Moraxella vaccine was 4.2 million (31%). Using the base-case vaccine costs, pneumococcal-nontypeable H influenzae vaccine use would result in net savings compared with nontypeable 7-valent pneumococcal conjugate use. Conversely, pneumococcal-nontypeable H influenzae-Moraxella vaccine use would not

Estimating the herd immunity effect of rotavirus vaccine.

Science.gov (United States)

Pollard, Suzanne L; Malpica-Llanos, Tanya; Friberg, Ingrid K; Fischer-Walker, Christa; Ashraf, Sania; Walker, Neff

2015-07-31

Diarrhea is one of the leading causes of death in children under 5, and an estimated 39% of these deaths are attributable to rotavirus. Currently two live, oral rotavirus vaccines have been introduced on the market; however, the herd immunity effect associated with rotavirus vaccine has not yet been quantified. The purpose of this meta-analysis was to estimate the herd immunity effects associated with rotavirus vaccines. We performed a systematic literature review of articles published between 2008 and 2014 that measured the impact of rotavirus vaccine on severe gastroenteritis (GE) morbidity or mortality. We assessed the quality of published studies using a standard protocol and conducted meta-analyses to estimate the herd immunity effect in children less than one year of age across all years presented in the studies. We conducted these analyses separately for studies reporting a rotavirus-specific GE outcome and those reporting an all-cause GE outcome. In studies reporting a rotavirus-specific GE outcome, four of five of which were conducted in the United States, the median herd effect across all study years was 22% [19-25%]. In studies reporting an all-cause GE outcome, all of which were conducted in Latin America, the median herd effect was 24.9% [11-30%]. There is evidence that rotavirus vaccination confers a herd immunity effect in children under one year of age in the United States and Latin American countries. Given the high variability in vaccine efficacy across regions, more studies are needed to better examine herd immunity effects in high mortality regions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Estimating effectiveness of HPV vaccination against HPV infection from post-vaccination data in the absence of baseline data.

Science.gov (United States)

Vänskä, Simopekka; Söderlund-Strand, Anna; Uhnoo, Ingrid; Lehtinen, Matti; Dillner, Joakim

2018-04-28

HPV vaccination programs have been introduced in large parts of the world, but monitoring of effectiveness is not routinely performed. Many countries introduced vaccination programs without establishing the baseline of HPV prevalences. We developed and validated methods to estimate protective effectiveness (PE) of vaccination from the post-vaccination data alone using references, which are invariant under HPV vaccination. Type-specific HPV prevalence data for 15-39 year-old women were collected from the pre- and post-vaccination era in a region in southern Sweden. In a region in middle Sweden, where no baseline data had been collected, only post-vaccination data was collected. The age-specific baseline prevalence of vaccine HPV types (vtHPV, HPV 6, 11, 16, 18) were reconstructed as Beta distributions from post-vaccination data by applying the reference odds ratios between the target HPV type and non-vaccine-type HPV (nvtHPV) prevalences. Older non-vaccinated age cohorts and the southern Sweden region were used as the references. The methods for baseline reconstructions were validated by computing the Bhattacharyya coefficient (BC), a measure for divergence, between reconstructed and actual observed prevalences for vaccine HPV types in Southern Sweden, and in addition, for non-vaccine types in both regions. The PE estimates among 18-21 year-old women were validated by comparing the PE estimates that were based on the reconstructed baseline prevalences against the PE estimates based on the actual baseline prevalences. In Southern Sweden the PEs against vtHPV were 52.2% (95% CI: 44.9-58.5) using the reconstructed baseline and 49.6% (43.2-55.5) using the actual baseline, with high BC 82.7% between the reconstructed and actual baseline. In the middle Sweden region where baseline data was missing, the PE was estimated at 40.5% (31.6-48.5). Protective effectiveness of HPV vaccination can be estimated from post-vaccination data alone via reconstructing the baseline

Live-attenuated tetravalent dengue vaccines: The needs and challenges of post-licensure evaluation of vaccine safety and effectiveness.

Science.gov (United States)

Wichmann, Ole; Vannice, Kirsten; Asturias, Edwin J; de Albuquerque Luna, Expedito José; Longini, Ira; Lopez, Anna Lena; Smith, Peter G; Tissera, Hasitha; Yoon, In-Kyu; Hombach, Joachim

2017-10-09

Since December 2015, the first dengue vaccine has been licensed in several Asian and Latin American countries for protection against disease from all four dengue virus serotypes. While the vaccine demonstrated an overall good safety and efficacy profile in clinical trials, some key research questions remain which make risk-benefit-assessment for some populations difficult. As for any new vaccine, several questions, such as very rare adverse events following immunization, duration of vaccine-induced protection and effectiveness when used in public health programs, will be addressed by post-licensure studies and by data from national surveillance systems after the vaccine has been introduced. However, the complexity of dengue epidemiology, pathogenesis and population immunity, as well as some characteristics of the currently licensed vaccine, and potentially also future, live-attenuated dengue vaccines, poses a challenge for evaluation through existing monitoring systems, especially in low and middle-income countries. Most notable are the different efficacies of the currently licensed vaccine by dengue serostatus at time of first vaccination and by dengue virus serotype, as well as the increased risk of dengue hospitalization among young vaccinated children observed three years after the start of vaccination in one of the trials. Currently, it is unknown if the last phenomenon is restricted to younger ages or could affect also seronegative individuals aged 9years and older, who are included in the group for whom the vaccine has been licensed. In this paper, we summarize scientific and methodological considerations for public health surveillance and targeted post-licensure studies to address some key research questions related to live-attenuated dengue vaccines. Countries intending to introduce a dengue vaccine should assess their capacities to monitor and evaluate the vaccine's effectiveness and safety and, where appropriate and possible, enhance their surveillance

Vaccination against Lyme disease: Are we ready for it?

Science.gov (United States)

Kaaijk, Patricia; Luytjes, Willem

2016-03-03

Lyme disease is the most common tick-borne illness in the Northern hemisphere and is caused by spirochetes of the Borrelia burgdorferi sensu lato complex. A first sign of Borrelia infection is a circular skin rash, erythema migrans, but it can develop to more serious manifestations affecting skin, nervous system, joints, and/or heart. The marked increase in Lyme disease incidence over the past decades, the severity of the disease, and the associated high medical costs of, in particular, the persistent forms of Lyme disease requires adequate measures for control. Vaccination would be the most effective intervention for prevention, but at present no vaccine is available. In the 1990s, 2 vaccines against Lyme disease based on the OspA protein from the predominant Borrelia species of the US showed to be safe and effective in clinical phase III studies. However, failed public acceptance led to the demise of these monovalent OspA-based vaccines. Nowadays, public seem to be more aware of the serious health problems that Lyme disease can cause and seem more ready for the use of a broadly protective vaccine. This article discusses several aspects that should be considered to enable the development and implementation of a vaccine to prevent Lyme disease successfully.

Prolonging herd immunity to cholera via vaccination: Accounting for human mobility and waning vaccine effects.

Directory of Open Access Journals (Sweden)

Corey M Peak

2018-02-01

Full Text Available Oral cholera vaccination is an approach to preventing outbreaks in at-risk settings and controlling cholera in endemic settings. However, vaccine-derived herd immunity may be short-lived due to interactions between human mobility and imperfect or waning vaccine efficacy. As the supply and utilization of oral cholera vaccines grows, critical questions related to herd immunity are emerging, including: who should be targeted; when should revaccination be performed; and why have cholera outbreaks occurred in recently vaccinated populations?We use mathematical models to simulate routine and mass oral cholera vaccination in populations with varying degrees of migration, transmission intensity, and vaccine coverage. We show that migration and waning vaccine efficacy strongly influence the duration of herd immunity while birth and death rates have relatively minimal impacts. As compared to either periodic mass vaccination or routine vaccination alone, a community could be protected longer by a blended "Mass and Maintain" strategy. We show that vaccination may be best targeted at populations with intermediate degrees of mobility as compared to communities with very high or very low population turnover. Using a case study of an internally displaced person camp in South Sudan which underwent high-coverage mass vaccination in 2014 and 2015, we show that waning vaccine direct effects and high population turnover rendered the camp over 80% susceptible at the time of the cholera outbreak beginning in October 2016.Oral cholera vaccines can be powerful tools for quickly protecting a population for a period of time that depends critically on vaccine coverage, vaccine efficacy over time, and the rate of population turnover through human mobility. Due to waning herd immunity, epidemics in vaccinated communities are possible but become less likely through complementary interventions or data-driven revaccination strategies.

Approaches and Perspectives for Development of African Swine Fever Virus Vaccines

Directory of Open Access Journals (Sweden)

Marisa Arias

2017-10-01

Full Text Available African swine fever (ASF is a complex disease of swine, caused by a large DNA virus belonging to the family Asfarviridae. The disease shows variable clinical signs, with high case fatality rates, up to 100%, in the acute forms. ASF is currently present in Africa and Europe where it circulates in different scenarios causing a high socio-economic impact. In most affected regions, control has not been effective in part due to lack of a vaccine. The availability of an effective and safe ASFV vaccines would support and enforce control–eradication strategies. Therefore, work leading to the rational development of protective ASF vaccines is a high priority. Several factors have hindered vaccine development, including the complexity of the ASF virus particle and the large number of proteins encoded by its genome. Many of these virus proteins inhibit the host’s immune system thus facilitating virus replication and persistence. We review previous work aimed at understanding ASFV–host interactions, including mechanisms of protective immunity, and approaches for vaccine development. These include live attenuated vaccines, and “subunit” vaccines, based on DNA, proteins, or virus vectors. In the shorter to medium term, live attenuated vaccines are the most promising and best positioned candidates. Gaps and future research directions are evaluated.

Principles underlying rational design of live attenuated influenza vaccines

Science.gov (United States)

Jang, Yo Han

2012-01-01

Despite recent innovative advances in molecular virology and the developments of vaccines, influenza virus remains a serious burden for human health. Vaccination has been considered a primary countermeasure for prevention of influenza infection. Live attenuated influenza vaccines (LAIVs) are particularly attracting attention as an effective strategy due to several advantages over inactivated vaccines. Cold-adaptation, as a classical means for attenuating viral virulence, has been successfully used for generating safe and effective donor strains of LAIVs against seasonal epidemics and occasional pandemics. Recently, the advent of reverse genetics technique expedited a variety of rational strategies to broaden the pool of LAIVs. Considering the breadth of antigenic diversity of influenza virus, the pool of LAIVs is likely to equip us with better options for controlling influenza pandemics. With a brief reflection on classical attenuating strategies used at the initial stage of development of LAIVs, especially on the principles underlying the development of cold-adapted LAIVs, we further discuss and outline other attenuation strategies especially with respect to the rationales for attenuation, and their practicality for mass production. Finally, we propose important considerations for a rational vaccine design, which will provide us with practical guidelines for improving the safety and effectiveness of LAIVs. PMID:23596576

Development and trial of vaccines against Brucella.

Science.gov (United States)

Lalsiamthara, Jonathan; Lee, John Hwa

2017-08-31

The search for ideal brucellosis vaccines remains active today. Currently, no licensed human or canine anti-brucellosis vaccines are available. In bovines, the most successful vaccine (S19) is only used in calves, as adult vaccination results in orchitis in male, prolonged infection, and possible abortion complications in pregnant female cattle. Another widely deployed vaccine (RB51) has a low protective efficacy. An ideal vaccine should exhibit a safe profile as well as enhance protective efficacy. However, currently available vaccines exhibit one or more major drawbacks. Smooth live attenuated vaccines suffer shortcomings such as residual virulence and serodiagnostic interference. Inactivated vaccines, in general, confer relatively low levels of protection. Recent developments to improve brucellosis vaccines include generation of knockout mutants by targeting genes involved in metabolism, virulence, and the lipopolysaccharide synthesis pathway, as well as generation of DNA vaccines, mucosal vaccines, and live vectored vaccines, have all produced varying degrees of success. Herein, we briefly review the bacteriology, pathogenesis, immunological implications, candidate vaccines, vaccinations, and models related to Brucella .

The impact of new technologies on vaccines.

Science.gov (United States)

Talwar, G P; Diwan, M; Razvi, F; Malhotra, R

1999-01-01

Vast changes are taking place in vaccinology consequent to the introduction of new technologies. Amongst the vaccines included in the Expanded Programme of Immunization (EPI), the pertussis vaccine has been replaced by acellular purified fractions devoid of side-effects. Non-pathogenic but immunogenic mutants of tetanus and diptheria toxins are likely to replace the toxoids. An effective vaccine against hepatitis B prepared by recombinant technology is in large-scale use. Conjugated vaccines against Haemophilus influenzae b, S. pneumococcus and meningococcus are now available, as also vaccines against mumps, rubella and measles. Combination vaccines have been devised to limit the number of injections. Vaccine delivery systems have been developed to deliver multiple doses of the vaccine at a single contact point. A genetically-engineered oral vaccine for typhoid imparts better and longer duration of immunity. Oral vaccines for cholera and other enteric infections are under clinical trials. The nose as a route for immunization is showing promise for mucosal immunity and for anti-inflammatory experimental vaccines against multiple sclerosis and insulin-dependent diabetes mellitus. The range of vaccines has expanded to include pathogens resident in the body such as Helicobacter pylori (duodenal ulcer), S. mutans (dental caries), and human papilloma virus (carcinoma of the cervix). An important progress is the recognition that DNA alone can constitute the vaccines, inducing both humoral and cell-mediated immune responses. A large number of DNA vaccines have been made and shown interesting results in experimental animals. Live recombinant vaccines against rabies and rinderpest have proven to be highly effective for controlling these infections in the field, and those for AIDS are under clinical trial. Potent adjuvants have added to the efficacy of the vaccines. New technologies have emerged to 'humanize' mouse monoclonals by genetic engineering and express these

Impact and cost-effectiveness of rotavirus vaccination in Bangladesh.

Science.gov (United States)

Pecenka, Clint; Parashar, Umesh; Tate, Jacqueline E; Khan, Jahangir A M; Groman, Devin; Chacko, Stephen; Shamsuzzaman, Md; Clark, Andrew; Atherly, Deborah

2017-07-13

Diarrheal disease is a leading cause of child mortality globally, and rotavirus is responsible for more than a third of those deaths. Despite substantial decreases, the number of rotavirus deaths in children under five was 215,000 per year in 2013. Of these deaths, approximately 41% occurred in Asia and 3% of those in Bangladesh. While Bangladesh has yet to introduce rotavirus vaccination, the country applied for Gavi support and plans to introduce it in 2018. This analysis evaluates the impact and cost-effectiveness of rotavirus vaccination in Bangladesh and provides estimates of the costs of the vaccination program to help inform decision-makers and international partners. This analysis used Pan American Health Organization's TRIVAC model (version 2.0) to examine nationwide introduction of two-dose rotavirus vaccination in 2017, compared to no vaccination. Three mortality scenarios (low, high, and midpoint) were assessed. Benefits and costs were examined from the societal perspective over ten successive birth cohorts with a 3% discount rate. Model inputs were locally acquired and complemented by internationally validated estimates. Over ten years, rotavirus vaccination would prevent 4000 deaths, nearly 500,000 hospitalizations and 3 million outpatient visits in the base scenario. With a Gavi subsidy, cost/disability adjusted life year (DALY) ratios ranged from $58/DALY to $142/DALY averted. Without a Gavi subsidy and a vaccine price of $2.19 per dose, cost/DALY ratios ranged from $615/DALY to $1514/DALY averted. The discounted cost per DALY averted was less than the GDP per capita for nearly all scenarios considered, indicating that a routine rotavirus vaccination program is highly likely to be cost-effective. Even in a low mortality setting with no Gavi subsidy, rotavirus vaccination would be cost-effective. These estimates exclude the herd immunity benefits of vaccination, so represent a conservative estimate of the cost-effectiveness of rotavirus vaccination

The effectiveness of vaccine day and educational interventions on influenza vaccine coverage among health care workers at long-term care facilities.

Science.gov (United States)

Kimura, Akiko C; Nguyen, Christine N; Higa, Jeffrey I; Hurwitz, Eric L; Vugia, Duc J

2007-04-01

We examined barriers to influenza vaccination among long-term care facility (LTCF) health care workers in Southern California and developed simple, effective interventions to improve influenza vaccine coverage of these workers. In 2002, health care workers at LTCFs were surveyed regarding their knowledge and attitudes about influenza and the influenza vaccine. Results were used to develop 2 interventions, an educational campaign and Vaccine Day (a well-publicized day for free influenza vaccination of all employees at the worksite). Seventy facilities were recruited to participate in an intervention trial and randomly assigned to 4 study groups. The combination of Vaccine Day and an educational campaign was most effective in increasing vaccine coverage (53% coverage; prevalence ratio [PR]=1.45; 95% confidence interval [CI]=1.24, 1.71, compared with 27% coverage in the control group). Vaccine Day alone was also effective (46% coverage; PR= 1.41; 95% CI=1.17, 1.71). The educational campaign alone was not effective in improving coverage levels (34% coverage; PR=1.18; 95% CI=0.93, 1.50). Influenza vaccine coverage of LTCF health care workers can be improved by providing free vaccinations at the worksite with a well-publicized Vaccine Day.

Effectiveness of 2010/2011 seasonal influenza vaccine in Ireland.

LENUS (Irish Health Repository)

Barret, A S

2012-02-01

We conducted a case-control study to estimate the 2010\\/2011 trivalent influenza vaccine effectiveness (TIVE) using the Irish general practitioners\\' influenza sentinel surveillance scheme. Cases were influenza-like illness (ILI) patients with laboratory-confirmed influenza. Controls were ILI patients who tested negative for influenza. Participating sentinel general practitioners (GP) collected swabs from patients presenting with ILI along with their vaccination history and other individual characteristics. The TIVE was computed as (1 - odds ratiofor vaccination) x100%. Of 60 sentinel GP practices, 22 expressed interest in participating in the study and 17 (28%) recruited at least one ILI patient. In the analysis, we included 106 cases and 85 controls. Seven controls (8.2%) and one influenza case (0.9%) had been vaccinated in 2010\\/2011. The estimated TIVE against any influenza subtype was 89.4% [95% CI: 13.8; 99.8%], suggesting a protective effect against GP-attended laboratory confirmed influenza. This study design could be used to monitor influenza vaccine effectiveness annually but sample size and vaccination coverage should be increased to obtain precise and adjusted estimates.

A novel rabies vaccine based-on toll-like receptor 3 (TLR3) agonist PIKA adjuvant exhibiting excellent safety and efficacy in animal studies

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yi [Yisheng Biopharma. Co., Ltd., Beijing (China); Zhang, Shoufeng [Academy of Military Medical Sciences, Changchun (China); Li, Wei [National Center for Safety Evaluation of Drugs, Beijing (China); Hu, Yuchi; Zhao, Jinyan [Beijing Institute for Drug Control, Beijing (China); Liu, Fang; Lin, Haixiang; Liu, Yuan; Wang, Liliang; Xu, Shu [Yisheng Biopharma. Co., Ltd., Beijing (China); Hu, Rongliang, E-mail: ronglianghu@hotmail.com [Academy of Military Medical Sciences, Changchun (China); Shao, Hui, E-mail: hui.shao@yishengbio.com [Yisheng Biopharma. Co., Ltd., Beijing (China); Li, Lietao, E-mail: lietao.li@gmail.com [Yisheng Biopharma. Co., Ltd., Beijing (China)

2016-02-15

Vaccination alone is not sufficiently effective to protect human from post-exposure rabies virus infection due to delayed generation of rabies virus neutralizing antibodies and weak cellular immunity. Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as adjuvant of rabies vaccine. The efficacy and safety of PIKA rabies vaccine were evaluated. The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group (control) was 20–30%. According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to develop next-generation rabies vaccine and encourage the start of clinical studies. - Highlights: • Vaccination alone is not effective to protect human from rabies virus infection due to delayed generation of rabies virus neutralizing antibodies (RVNA) and weak cellular immunity. • Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as an adjuvant of rabies vaccine. • The efficacy and safety of PIKA rabies vaccine was evaluated in mice. • The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. • After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group was only 20–30%. • According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. • Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to

A novel rabies vaccine based-on toll-like receptor 3 (TLR3) agonist PIKA adjuvant exhibiting excellent safety and efficacy in animal studies

International Nuclear Information System (INIS)

Zhang, Yi; Zhang, Shoufeng; Li, Wei; Hu, Yuchi; Zhao, Jinyan; Liu, Fang; Lin, Haixiang; Liu, Yuan; Wang, Liliang; Xu, Shu; Hu, Rongliang; Shao, Hui; Li, Lietao

2016-01-01

Vaccination alone is not sufficiently effective to protect human from post-exposure rabies virus infection due to delayed generation of rabies virus neutralizing antibodies and weak cellular immunity. Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as adjuvant of rabies vaccine. The efficacy and safety of PIKA rabies vaccine were evaluated. The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group (control) was 20–30%. According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to develop next-generation rabies vaccine and encourage the start of clinical studies. - Highlights: • Vaccination alone is not effective to protect human from rabies virus infection due to delayed generation of rabies virus neutralizing antibodies (RVNA) and weak cellular immunity. • Therefore, it is vital to develop safer and more efficacious vaccine against rabies. PIKA, a stabilized chemical analog of double-stranded RNA that interacts with TLR3, was employed as an adjuvant of rabies vaccine. • The efficacy and safety of PIKA rabies vaccine was evaluated in mice. • The results showed that PIKA rabies vaccine enhanced both humoral and cellular immunity. • After viral challenge, PIKA rabies vaccine protected 70–80% of animals, while the survival rate of non-adjuvant vaccine group was only 20–30%. • According to the results of toxicity tests, PIKA and PIKA rabies vaccine are shown to be well tolerated in mice. • Thus, this study indicates that PIKA rabies vaccine is an effective and safe vaccine which has the potential to

The safety and immunogenicity of influenza vaccine in children with asthma in Mexico.

Science.gov (United States)

Pedroza, Alvaro; Huerta, José G; Garcia, Maria de la Luz; Rojas, Arsheli; López-Martínez, Irma; Penagos, Martín; Franco-Paredes, Carlos; Deroche, Christele; Mascareñas, Cesar

2009-07-01

The morbidity and mortality associated with influenza is substantial in children with asthma. There are no available data on the safety and immunogenicity of influenza vaccine in children with asthma in Latin America. Furthermore, it is unclear if influenza vaccination may cause asthma exacerbations. We conducted a placebo-controlled trial to investigate the safety and immunogenicity of an inactivated trivalent split virus influenza vaccine in children with asthma in Mexico. We also measured the impact of influenza vaccination on pulmonary function tests in this population. The inactivated influenza vaccine was immunogenic and safe in terms of local and systemic side effects compared to placebo. We observed no significant impact on pulmonary function tests among vaccine recipients. Given the significant morbidity associated with influenza in children, strategies to promote increased influenza vaccination coverage in this high-risk group in Latin America and elsewhere are urgently needed.

Non-specific Effects of Vaccines and Stunting: Timing May Be Essential

Directory of Open Access Journals (Sweden)

Mike L.T. Berendsen

2016-06-01

Conclusions: We found a general time-dependent pattern of non-specific effects of vaccination, with positive associations for vaccinations given early in life and negative associations for vaccinations given later in infancy. If confirmed in further research, our findings may provide a new perspective on the non-specific effects of vaccination.

Xenogeneic murine tyrosinase DNA vaccine for malignant melanoma of the digit of dogs.

Science.gov (United States)

Manley, C A; Leibman, N F; Wolchok, J D; Rivière, I C; Bartido, S; Craft, D M; Bergman, P J

2011-01-01

Malignant melanoma of dogs is a highly aggressive neoplasm and is the 2nd most common digit tumor. Metastatic disease is a common sequela for which few effective treatment options exist. Studies show that xenogeneic tyrosinase DNA vaccination yields immune responses and prolongation of survival in dogs with oral malignant melanoma. Describe clinical findings and tumor characteristics of a cohort of dogs with digit malignant melanoma, and evaluate the prognostic utility of a proposed staging system. Determine if a novel xenogeneic DNA vaccine is safe and potentially effective for treatment of dogs with digit melanoma. Fifty-eight dogs with digit malignant melanoma treated at the Animal Medical Center between 2004 and 2007. Retrospective, medical records review of dogs with digit melanoma treated with xenogeneic DNA vaccine. Overall median survival time (MST) for dogs treated with loco-regional control and xenogeneic DNA vaccine was 476 days with a 1-year survival rate of 63%. MST for dogs presenting with metastasis was 105 days versus 533 days for dogs presenting without metastasis (P dogs in the latter group were alive at 2 and 3 years. A proposed staging system proved prognostic with stages I-IV dogs surviving >952, >1,093, 321, and 76 days, respectively. The xenogeneic murine tyrosinase DNA vaccine was safe and appears effective when used in conjunction with local and regional disease control. The proposed staging system was prognostic in this study and future studies might benefit from utilizing this staging system. Copyright © 2010 by the American College of Veterinary Internal Medicine.

Adjuvanted vaccines: Aspects of immunosafety and modes of action

NARCIS (Netherlands)

Aalst, Susan van

2017-01-01

New developments in vaccine design shift towards safe, though sometimes less immunogenic, subunit and synthetic antigens. Therefore, the majority of current vaccines require adjuvants to increase immunogenicity. Most adjuvants available were developed empirically and their mode of action is only

A Rapporteur's Summary : Research on Dengue Vaccine

OpenAIRE

Kitamura, Takashi

1994-01-01

Dengue virus is a member of flavivirus group. Diseases caused by flaviviruses have been a scourge of mankind for long history of human kind; with yellow fever at the top, followed by dengue fever, Japanese encephalitis (JE) and Russian spring-summer encephalitis (RSSE). Due to the dvevelopment of a safe and efficacious live-attenuated vaccine against yellow fever as a first laboratory-designed virus vaccine, this disease is no longer a threat in countries where adequate vaccination is practic...

Estimates of pandemic influenza vaccine effectiveness in Europe, 2009-2010: results of Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE multicentre case-control study.

Directory of Open Access Journals (Sweden)

Marta Valenciano

2011-01-01

Full Text Available BACKGROUND: A multicentre case-control study based on sentinel practitioner surveillance networks from seven European countries was undertaken to estimate the effectiveness of 2009-2010 pandemic and seasonal influenza vaccines against medically attended influenza-like illness (ILI laboratory-confirmed as pandemic influenza A (H1N1 (pH1N1. METHODS AND FINDINGS: Sentinel practitioners swabbed ILI patients using systematic sampling. We included in the study patients meeting the European ILI case definition with onset of symptoms >14 days after the start of national pandemic vaccination campaigns. We compared pH1N1 cases to influenza laboratory-negative controls. A valid vaccination corresponded to >14 days between receiving a dose of vaccine and symptom onset. We estimated pooled vaccine effectiveness (VE as 1 minus the odds ratio with the study site as a fixed effect. Using logistic regression, we adjusted VE for potential confounding factors (age group, sex, month of onset, chronic diseases and related hospitalizations, smoking history, seasonal influenza vaccinations, practitioner visits in previous year. We conducted a complete case analysis excluding individuals with missing values and a multiple multivariate imputation to estimate missing values. The multivariate imputation (n = 2902 adjusted pandemic VE (PIVE estimates were 71.9% (95% confidence interval [CI] 45.6-85.5 overall; 78.4% (95% CI 54.4-89.8 in patients <65 years; and 72.9% (95% CI 39.8-87.8 in individuals without chronic disease. The complete case (n = 1,502 adjusted PIVE were 66.0% (95% CI 23.9-84.8, 71.3% (95% CI 29.1-88.4, and 70.2% (95% CI 19.4-89.0, respectively. The adjusted PIVE was 66.0% (95% CI -69.9 to 93.2 if vaccinated 8-14 days before ILI onset. The adjusted 2009-2010 seasonal influenza VE was 9.9% (95% CI -65.2 to 50.9. CONCLUSIONS: Our results suggest good protection of the pandemic monovalent vaccine against medically attended pH1N1 and no effect of the

Toward the development of a one-dose classical swine fever subunit vaccine: antigen titration, immunity onset, and duration of immunity

Science.gov (United States)

Madera, Rachel F.; Wang, Lihua; Gong, Wenjie; Burakova, Yulia; Buist, Sterling; Nietfeld, Jerome; Henningson, Jamie; Cino-Ozuna, Ada G.; Tu, Changchun

2018-01-01

Highly contagious classical swine fever (CSF) remains a major trade and health problem in the pig industry, resulting in large economic losses worldwide. In CSF-endemic countries, attenuated CSF virus (CSFV) vaccines have been routinely used to control the disease. However, eradication of CSFV in a geographical area would require permanent reduction to zero presence of the virus. It is therefore of paramount importance to develop a safe, potent, and non-infectious CSF vaccine. We have previously reported on a cost-effective CSF E2 subunit vaccine, KNB-E2, which can protect against CSF symptoms in a single dose containing 75 µg of recombinant CSFV glycoprotein E2. In this study, we report on a series of animal studies undertaken to elucidate further the efficacy of KNB-E2. We found that pigs vaccinated with a single KNB-E2 dose containing 25 µg of recombinant CSFV glycoprotein E2 were protected from clinical symptoms of CSF. In addition, KNB-E2-mediated reduction of CSF symptoms was observed at two weeks post-vaccination and the vaccinated pigs continued to exhibit reduced CSF clinical signs when virus challenged at two months and four months post-vaccination. These results suggest that KNB-E2 effectively reduces CSF clinical signs, indicating the potential of this vaccine for safely minimizing CSF-related losses. PMID:29510474

Possible Triggering Effect of Influenza Vaccination on Psoriasis

Directory of Open Access Journals (Sweden)

Ali Tahsin Gunes

2015-01-01

Full Text Available Psoriasis is a chronic, recurrent, immune-mediated inflammatory disease and it can be provoked or exacerbated by a variety of different environmental factors, particularly infections and drugs. In addition, a possible association between vaccination and the new onset and/or exacerbation of psoriasis has been reported by a number of different authors. The aim of this study is to investigate the effects of influenza vaccination on patients with psoriasis. Here, we report the findings from 43 patients suffering from psoriasis (clinical phenotypes as mixed guttate/plaque lesions, palmoplantar or scalp psoriasis whose diseases had been triggered after influenza vaccination applied in the 2009-2010 season. The short time intervals between vaccination and psoriasis flares in our patients and the lack of other possible triggers suggest that influenza vaccinations may have provocative effects on psoriasis. However, further large and controlled studies need to be carried out to confirm this relationship.

Effectiveness of hepatitis A vaccination as post-exposure prophylaxis

Science.gov (United States)

Parrón, Ignasi; Planas, Caritat; Manzanares-Laya, Sandra; Martínez, Ana; Sala, Maria Rosa; Minguell, Sofia; Jané, Mireia

2017-01-01

ABSTRACT Hepatitis A (HA) has been a vaccine-preventable disease since 1995. In Catalonia, a universal combined hepatitis A+B vaccination program of preadolescents was initiated at the end of 1998. However, outbreaks are reported each year and post-exposure prophylaxis (PEP) with hepatitis A virus (HAV) vaccine or immunoglobulin (IG) is recommended to avoid cases. The aim of this study was to assess the effectiveness of HAV vaccine and IG in preventing hepatitis A cases in susceptible exposed people. A retrospective cohort study of contacts of HA cases involved in outbreaks reported in Catalonia between January 2006 and December 2012 was made. The rate ratios and 95% confidence intervals (CI) of HA in susceptible contacts receiving HAV or IG versus those without PEP were calculated. There were 3550 exposed persons in the outbreaks studied: 2381 received one dose of HAV vaccine (Hepatitis A or hepatitis A+B), 190 received IG, and 611 received no PEP. 368 exposed subjects received one dose of HAV vaccine and IG simultaneously and were excluded from the study. The effectiveness of PEP was 97.6% (95% CI 96.2–98.6) for HAV vaccine and 98.3% (95% CI 91.3–99.9) for IG; the differences were not statistically significant (p = 0.36). The elevated effectiveness of HAV vaccination for PEP in HA outbreaks, similar to that of IG, and the long-term protection of active immunization, supports the preferential use of vaccination to avoid secondary cases. PMID:27925847

[Clinical effectiveness and economical evaluation of preventive vaccination].

Science.gov (United States)

Vaz Carneiro, António; Belo, Ana Isabel; Gouveia, Miguel; Costa, João; Borges, Margarida

2011-01-01

The value of mass vaccination as a preventive measure for infectious diseases is one of the most important advances of modern Medicine. The impact on incidence of several infectious diseases, until recently responsible for significant morbidity and mortality at world level, is well proved in a series of high quality epidemiological studies. In this scientific review we aimed firstly to briefly resume the history of mass vaccination and its scientists, responsible for synthesis and marketing of these drugs. In second place we present a group of a few disease preventable by vaccines as well as the Portuguese National Vaccination Plan and its benefits. In third place we identified groups of subjects in which a well structured vaccination plan is particularly important, as well as the correspondent diseases to be covered by vaccination. Fourthly, we discussed the ethical considerations of vaccination, and its tensions between subject autonomy and society advantages in com pulsive programs. Fifthly, we analyzed clinical effectiveness of vaccines through the concept of herd immunity, clinical evaluation of immune response to vaccines and some examples of systematic reviews on three relevant diseases (influenza, meningococcal and pneumococcal infections). In sixth place we discussed vaccine safety presenting monitoring methods of vaccination risks, as well as discussing the public myths concerning vaccines. Finally we present a economic analysis of preventive vaccination with a review of some published literature on specific diseases. We conclude that mass vaccination is a efficacious preventive measure, as well as a economic rational choice, and that this public health intervention should be a pillar of a modern preventive system.

Recombinant vaccines against T. gondii: comparison between homologous and heterologous vaccination protocols using two viral vectors expressing SAG1.

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Mendes, Érica Araújo; Fonseca, Flavio G; Casério, Bárbara M; Colina, Janaína P; Gazzinelli, Ricardo Tostes; Caetano, Braulia C

2013-01-01

The use of recombinant viral vectors expressing T. gondii antigens is a safe and efficient approach to induce immune response against the parasite and a valuable tool for vaccine development. We have previously protected mice from toxoplasmosis by immunizing the animals with an adenovirus expressing the protein SAG1 (AdSAG1) of T. gondii. We are now looking for ways to improve the vaccination strategy and enhance protection. One limitation of homologous vaccinations (sequential doses of the same vector) is induction of anti-vector immune response that blocks cell transduction, restricts transgene expression and, consequently, compromises the overall outcome of vaccination. One way to avert the effects of anti-vector response is to use different viruses in prime and boost (heterologous vaccination). Bearing this in mind, we generated a modified Vaccinia Virus Ankara encoding SAG1 (MVASAG1), to be tested as boost agent after prime with AdSAG1. Although minor differences were observed in the magnitude of the anti-SAG1 immune response induced by each vaccination protocol, the heterologous immunization with AdSAG1 followed by MVASAG1 resulted in improved capacity to control brain cyst formation in a model of chronic toxoplasmosis in C57BL/6 mice.

Recombinant vaccines against T. gondii: comparison between homologous and heterologous vaccination protocols using two viral vectors expressing SAG1.

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Érica Araújo Mendes

Full Text Available The use of recombinant viral vectors expressing T. gondii antigens is a safe and efficient approach to induce immune response against the parasite and a valuable tool for vaccine development. We have previously protected mice from toxoplasmosis by immunizing the animals with an adenovirus expressing the protein SAG1 (AdSAG1 of T. gondii. We are now looking for ways to improve the vaccination strategy and enhance protection. One limitation of homologous vaccinations (sequential doses of the same vector is induction of anti-vector immune response that blocks cell transduction, restricts transgene expression and, consequently, compromises the overall outcome of vaccination. One way to avert the effects of anti-vector response is to use different viruses in prime and boost (heterologous vaccination. Bearing this in mind, we generated a modified Vaccinia Virus Ankara encoding SAG1 (MVASAG1, to be tested as boost agent after prime with AdSAG1. Although minor differences were observed in the magnitude of the anti-SAG1 immune response induced by each vaccination protocol, the heterologous immunization with AdSAG1 followed by MVASAG1 resulted in improved capacity to control brain cyst formation in a model of chronic toxoplasmosis in C57BL/6 mice.

Policy considerations for improving influenza vaccination rates among pregnant women.

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Mollard, Elizabeth K; Guenzel, Nicholas; Brown, Peggy A; Keeler, Heidi J; Cramer, Mary E

2014-01-01

Influenza exposure during pregnancy can cause severe health problems for both the mother and her offspring, including an increased risk of mortality. Influenza vaccination during all trimesters of pregnancy is safe and effective, and recommended by professional organizations such as the American College of Obstetrics and Gynecology. Despite these recommendations, the U.S. vaccination rates remain low in this high-risk population. A policy analysis based on the five-part method identified by Teitelbaum and Wilensky () addresses factors to consider in identifying the best voluntary policy options to improve the vaccination rates. The authors provide discussion of the background, landscape, and stakeholder interests and the pros and cons of two voluntary policy options to increase vaccination. The policy options include: (a) financial incentives for providers and (b) an education emphasis for providers and staff. The authors conclude that based on considerations of cost, provider preference, and practicality of implementation, a continuing educational intervention is the preferred policy venue to increase vaccination rates. © 2014 Wiley Periodicals, Inc.

Recombinant viruses as vaccines against viral diseases

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A.P.D. Souza

2005-04-01

Full Text Available Vaccine approaches to infectious diseases are widely applied and appreciated. Amongst them, vectors based on recombinant viruses have shown great promise and play an important role in the development of new vaccines. Many viruses have been investigated for their ability to express proteins from foreign pathogens and induce specific immunological responses against these antigens in vivo. Generally, gene-based vaccines can stimulate potent humoral and cellular immune responses and viral vectors might be an effective strategy for both the delivery of antigen-encoding genes and the facilitation and enhancement of antigen presentation. In order to be utilized as a vaccine carrier, the ideal viral vector should be safe and enable efficient presentation of required pathogen-specific antigens to the immune system. It should also exhibit low intrinsic immunogenicity to allow for its re-administration in order to boost relevant specific immune responses. Furthermore, the vector system must meet criteria that enable its production on a large-scale basis. Several viral vaccine vectors have thus emerged to date, all of them having relative advantages and limits depending on the proposed application, and thus far none of them have proven to be ideal vaccine carriers. In this review we describe the potential, as well as some of the foreseeable obstacles associated with viral vaccine vectors and their use in preventive medicine.

Rotavirus vaccine and diarrhea mortality: quantifying regional variation in effect size

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Black Robert E

2011-04-01

Full Text Available Abstract Background Diarrhea mortality remains a leading cause of child death and rotavirus vaccine an effective tool for preventing severe rotavirus diarrhea. New data suggest vaccine efficacy may vary by region. Methods We reviewed published vaccine efficacy trials to estimate a regional-specific effect of vaccine efficacy on severe rotavirus diarrhea and hospitalizations. We assessed the quality of evidence using a standard protocol and conducted meta-analyses where more than 1 data point was available. Results Rotavirus vaccine prevented severe rotavirus episodes in all regions; 81% of episodes in Latin America, 42.7% of episodes in high-mortality Asia, 50% of episodes in sub-Saharan Africa, 88% of episodes low-mortality Asia and North Africa, and 91% of episodes in developed countries. The effect sizes observed for preventing severe rotavirus diarrhea will be used in LiST as the effect size for rotavirus vaccine on rotavirus-specific diarrhea mortality. Conclusions Vaccine trials have not measured the effect of vaccine on diarrhea mortality. The overall quality of the evidence and consistency observed across studies suggests that estimating mortality based on a severe morbidity reduction is highly plausible.

Travel and biologic therapy: travel-related infection risk, vaccine response and recommendations.

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Hall, Victoria; Johnson, Douglas; Torresi, Joseph

2018-01-01

Biologic therapy has revolutionized the management of refractory chronic autoimmune and auto-inflammatory disease, as well as several malignancies, providing rapid symptomatic relief and/or disease remission. Patients receiving biologic therapies have an improved quality of life, facilitating travel to exotic destinations and potentially placing them at risk of a range of infections. For each biologic agent, we review associated travel-related infection risk and expected travel vaccine response and effectiveness. A PUBMED search [vaccination OR vaccine] AND/OR ['specific vaccine'] AND/OR [immunology OR immune response OR response] AND [biologic OR biological OR biologic agent] was performed. A review of the literature was performed in order to develop recommendations on vaccination for patients in receipt of biologic therapy travelling to high-risk travel destinations. There is a paucity of literature in this area, however, it is apparent that travel-related infection risk is increased in patients on biologic therapy and when illness occurs they are at a higher risk of complication and hospitalization. Patients in receipt of biologic agents are deemed as having a high level of immunosuppression-live vaccines, including the yellow fever vaccine, are contraindicated. Inactivated vaccines are considered safe; however, vaccine response can be attenuated by the patient's biologic therapy, thereby resulting in reduced vaccine effectiveness and protection. Best practice requires a collaborative approach between the patient's primary healthcare physician, relevant specialist and travel medicine expert, who should all be familiar with the immunosuppressive and immunomodulatory effects resulting from the biologic therapies. Timing of vaccines should be carefully planned, and if possible, vaccination provided well before established immunosuppression.

IMMUNO-MODULATORY EFFECT OF INACTIVATED EIMERIA TENELLA VACCINE AND LIVE IMPPORTED COCCIDIAL VACCINE ON NEWCASTLE DISEASE VIRUS VACCINA TED BROILER CHICKS

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Muhammad Akram Muneer, Haji Ahmad Hashmi, Masood Rabbani, Zahid Munir Chaudhry and Ali M. Bahrami

2001-01-01

Full Text Available A total of 160 one-day-old broiler chicks were used to evaluate the immunomodulatory effects of an inactivated Eimeria tenella vaccine and a live polyvalent imported antiococcidial vaccine (Coccivac. This study indicated that both of these vaccines did not adversely affect the development of serum antibody against Newcastle disease virus (NDV and the chicks vaccinated with either of the anticoccidial vaccines resisted the virulent NDV challenge. A study of the lymphoid organs such as bursa of fabricuis: thymus and spleen from the experimental chicks indicated that those organs were comparable with those from the chicks not vaccinated with these coccidial vaccines. The overall findings of this study indicate that anticoccidial vaccines do not have any effects on the immune functions of the vaccinates. In fact these vaccines prevented the occurrence of clinical coccidiosis in the vaccinates.

HPV vaccines: their pathology-based discovery, benefits, and adverse effects.

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Nicol, Alcina F; de Andrade, Cecilia V; Russomano, Fabio B; Rodrigues, Luana S L; Oliveira, Nathalia S; Provance, David William; Nuovo, Gerard J

2015-12-01

The discovery of the human papillomavirus (HPV) vaccine illustrates the power of in situ-based pathologic analysis in better understanding and curing diseases. The 2 available HPV vaccines have markedly reduced the incidence of cervical intraepithelial neoplasias, genital warts, and cervical cancer throughout the world. Concerns about HPV vaccine safety have led some physicians, health care officials, and parents to refuse providing the recommended vaccination to the target population. The aims of the study were to discuss the discovery of HPV vaccine and review scientific data related to measurable outcomes from the use of HPV vaccines. The strong type-specific immunity against HPV in humans has been known for more than 25 years. Multiple studies confirm the positive risk benefit of HPV vaccination with minimal documented adverse effects. The most common adverse effect, injection site pain, occurred in about 10% of girls and was less than the rate reported for other vaccines. Use of HPV vaccine should be expanded into more diverse populations, mainly in low-resource settings. Copyright © 2015 Elsevier Inc. All rights reserved.

Yellow fever vaccine: an effective vaccine for travelers.

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Verma, Ramesh; Khanna, Pardeep; Chawla, Suraj

2014-01-01

Yellow fever (YF) is an acute viral communicable disease transmitted by an arbovirus of the Flavivirus genus. It is primarily a zoonotic disease, especially the monkeys. Worldwide, an estimated 200,000 cases of yellow fever occurred each year, and the case-fatality rate is ~15%. Forty-five endemic countries in Africa and Latin America, with a population of close to 1 billion, are at risk. Up to 50% of severely affected persons from YF die without treatment. During 2009, 55 cases and 18 deaths were reported from Brazil, Colombia, and Peru. Brazil reported the maximum number of cases and death, i.e., 42 cases with 11 deaths. From January 2010 to March 2011, outbreaks of YF were reported to the WHO by Cameroon, Democratic Republic of Congo, Cote d'Ivoire, Guinea, Sierra Leone, Senegal, and Uganda. Cases were also reported in three northern districts of Abim, Agago, and Kitugun near the border with South Sudan. YF usually causes fever, muscle pain with prominent backache, headache, shivers, loss of appetite, and nausea or vomiting. Most patients improve, and their symptoms disappear after 3 to 4 d. Half of the patients who enter the toxic phase die within 10-14 d, while the rest recover without significant organ damage. Vaccination has been the single most important measure for preventing YF. The 17D-204 YF vaccine is a freeze-dried, live attenuated, highly effective vaccine. It is available in single-dose or multi-dose vials and should be stored at 2-8 °C. It is reconstituted with normal saline and should be used within 1 h of reconstitution. The 0.5 mL dose is delivered subcutaneously. Revaccination is recommended every 10 y for people at continued risk of exposure to yellow fever virus (YFV). This vaccine is available worldwide. Travelers, especially to Africa or Latin America from Asia, must have a certificate documenting YF vaccination, which is required by certain countries for entry under the International Health Regulations (IHR) of the WHO.

Parental Expectation of Side Effects Following Vaccination Is Self-fulfilling: A Prospective Cohort Study.

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Smith, Louise E; Weinman, John; Amlôt, Richard; Yiend, Jenny; Rubin, G James

2018-06-02

One of the major factors contributing to parental refusal of vaccinations is the perception that vaccines cause side effects. Although symptoms are commonly reported following vaccinations, their causes are not always straightforward. Although some may be directly attributable to the vaccine itself, others may reflect pre-existing or coincidental symptoms that are misattributed to the vaccine. To investigate psychological factors associated with parental report of side effects following vaccination with the child influenza vaccine, and parental intention to re-vaccinate one's child the following year. A prospective cohort study was run in primary care practices in London in the 2016-2017 influenza season (ClinicalTrials.gov number NCT02909855). Two hundred seventy parents from 14 practices completed a questionnaire before their child's vaccination. Follow-up questionnaires were completed 3 days after vaccination and one month after vaccination. Parental report of side effects and vaccination intention for the subsequent year were measured. Parental report of side effects was strongly associated with pre-vaccination expectation of side effects. Suggestions received from the media, National Health Service (NHS) vaccination leaflet, and health care workers, as well as uncertainty-related beliefs, perceived sensitivity of the child to medicines, pessimism, and anxiety were also associated with reporting side effects. Side effect report was associated with lower vaccination intention for the following influenza season. Side effect perception following vaccination is influenced by psychological factors, in particular expectations. Perceiving side effects reduces future vaccination intention. Future public health communications should aim to decrease unrealistic expectations of side effects to increase vaccine uptake.

Clinical responses in patients with advanced colorectal cancer to a dendritic cell based vaccine

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Burgdorf, Stefan K; Fischer, Anders; Myschetzky, Peter S

2008-01-01

Patients with disseminated colorectal cancer have a poor prognosis. Preliminary studies have shown encouraging results from vaccines based on dendritic cells. The aim of this phase II study was to evaluate the effect of treating patients with advanced colorectal cancer with a cancer vaccine based...... with this DC-based cancer vaccine was safe and non-toxic. Stable disease was found in 24% (4/17) of the patients. The quality of life remained for most categories high and stable throughout the study period.......Patients with disseminated colorectal cancer have a poor prognosis. Preliminary studies have shown encouraging results from vaccines based on dendritic cells. The aim of this phase II study was to evaluate the effect of treating patients with advanced colorectal cancer with a cancer vaccine based......-testis antigens. Vaccines were biweekly administered intradermally with a total of 10 vaccines per patient. CT scans were performed and responses were graded according to the RECIST criteria. Quality of life was monitored with the SF-36 questionnaire. Toxicity and adverse events were graded according...

[Meningococcal C conjugate vaccine: Impact of a vaccination program and long-term effectiveness in Navarra, Spain, 2000-2014].

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Morales, Desirée; García-Cenoz, Manuel; Moreno, Laura; Bernaola, Enrique; Barricarte, Aurelio; Castilla, Jesús

2016-12-01

Since 2000, when the meningococcal serogroupC conjugate vaccine (MenCC) was introduced in the childhood immunization schedule in Spain, several changes in the schedule and catch-up campaigns have been performed. We aim to estimate the impact and effectiveness of this vaccine in Navarra up to 2014. The impact of the vaccination program was analysed by comparing incidence, mortality and lethality rates of disease before (1995-1999) and after (2004-2014) the introduction of the MenCC. Vaccine effectiveness was estimated using the screening method (Farrington) and the indirect cohort method (Broome). Data on cases were obtained from the active surveillance of meningococcal disease. During 1995-1999 the mean annual incidence of meningococcalC disease was 1.32 per 100,000, and 7.18 per 100,000 in children younger than 15years. The fall of meningococcalC disease incidence was significant in cohorts targeted for vaccination from the beginning and progressive in the general population. No cases were reported between 2011 and 2014. The estimated vaccine effectiveness was 96% by the screening method, and 99% by the indirect cohort method. The MenCC vaccination program has been successful in decreasing the incidence rate of serogroupC meningococcal disease in Navarra, and schedule changes have maintained high vaccine effectiveness throughout the study period. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Effect of DETOX as an adjuvant for melanoma vaccine.

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Schultz, N; Oratz, R; Chen, D; Zeleniuch-Jacquotte, A; Abeles, G; Bystryn, J C

1995-04-01

The identification of effective adjuvants is critical for tumor vaccine development. Towards this end, we examined whether the immunogenicity of a melanoma vaccine could be potentiated by DETOX, an adjuvant consisting of monophosphoryl lipid A (MPL) and purified mycobacterial cell-wall skeleton (CWS). Nineteen patients with resected stage III melanoma were immunized with a polyvalent melanoma antigen vaccine (40 micrograms) admixed with DETOX, q3 wks x 4. Seven patients received vaccine + low-dose DETOX (10 micrograms MPL + 100 micrograms CWS) and 12 received vaccine + high-dose DETOX (20 micrograms MPL + 200 micrograms CWS). A non-randomized control group of 35 patients was treated similarly with 40 micrograms vaccine + alum. One week after the fourth vaccine immunization, melanoma antibodies were increased over baseline in 7/7 (100%) patients treated with vaccine + low-dose DETOX, 8/12 (67%) patients treated with vaccine + high-dose DETOX, and in 4/19 (21%) of vaccine + alum patients. For the entire DETOX group, the antibody response rate was 15/19 (79%) compared 4/19 (21%) in the alum group (p or = 15 mm increase in DTH response over baseline) was induced in 50% of the entire DETOX group versus in 47% of the alum group. Median disease-free (DF) survival for the entire DETOX group was 17.8 months compared with 32.1 months in the alum group (p DETOX markedly potentiated antibody but had little effect on DTH responses to melanoma vaccine immunization. It did not appear to improve disease-free survival in comparison to alum in this non-randomized study.

Production of killed vaccine from Streptococcus sp. and its application in sea bass (Lates calcarifer

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Wanman, CH.

2007-09-01

Full Text Available Fish with an average length of 3.0-4.0 inches vaccinated with formalin-killed vaccine of Streptococcus sp. either by intraperitoneal injection and immersion methods had a survival rate of 100% indicating that the vaccine is safe to be used with sea bass. The highest efficacy was received when the vaccine containing bacterin at 2.50x1010 CFU/ml. Injection of vaccine together with adjuvant (CFA was highly effective against Streptococcus sp. infection. The relative percent survival (RPS of fish injected with vaccine alone and vaccine plus adjuvant were 100 (10 days post vaccination, 54.06 and 92.29 (20 days post vaccination and 31.58 and 73.68 (30 days post vaccination respectively. The fish which received vaccine by hyperosmotic immersion showed higher resistance to the disease than by direct immersion with the RPS of 30.77 and 71.80 (10 days post vaccination, 9.75 and 70.73 (20 days post vaccination and 7.14 and 16.67 (30 days post vaccination for direct immersion and hyperosmotic immersion, respectively.

Ebola hemorrhagic Fever and the current state of vaccine development.

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Hong, Joo Eun; Hong, Kee-Jong; Choi, Woo Young; Lee, Won-Ja; Choi, Yeon Hwa; Jeong, Chung-Hyeon; Cho, Kwang-Il

2014-12-01

Current Ebola virus outbreak in West Africa already reached the total number of 1,323 including 729 deaths by July 31st. the fatality is around 55% in the southeastern area of Guinea, Sierra Leone, Liberia, and Nigeria. The number of patients with Ebola Hemorrhagic Fever (EHF) was continuously increasing even though the any effective therapeutics or vaccines has not been developed yet. The Ebola virus in Guinea showed 98% homology with Zaire Ebola Virus. Study of the pathogenesis of Ebola virus infection and assess of the various candidates of vaccine have been tried for a long time, especially in United States and some European countries. Even though the attenuated live vaccine and DNA vaccine containing Ebola viral genes were tested and showed efficacy in chimpanzees, those candidates still need clinical tests requiring much longer time than the preclinical development to be approved for the practical treatment. It can be expected to eradicate Ebola virus by a safe and efficient vaccine development similar to the case of smallpox virus which was extinguished from the world by the variola vaccine.

Oral cholera vaccine--for whom, when, and why?

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Topps, Maureen H

2006-01-01

The search for a safe, effective, well tolerated, low cost vaccine against the ancient cholera enemy has been ongoing since the 19th century and has been revitalized in the past two decades since the advent of recombinant technology. Large-scale field trials have readily demonstrated the tolerability and safety of oral cholera vaccine in various forms. Variable levels of protection have been shown and one challenge has been to demonstrate whether this is a cost effective treatment in differing environments including its use in endemic and epidemic areas as well as for travelers. A review of recent literature was undertaken to assess the effectiveness and uses of currently available oral cholera vaccine. While the evidence does not support the creation of formal guidelines, some clear recommendations can be made. There is undoubtedly the potential to reduce the burden of illness both in endemic and epidemic situations. For travelers, certain higher risk groups may benefit from protection against cholera. More significantly, the short term cross-protection afforded by whole cell, B subunit (WC BS) oral cholera vaccine formulations against enterotoxigenic E. coli, (ETEC), the commonest causative agent of traveler's diarrhoea, may prove to be the most important raison d'être.

Vaccination strategies for future influenza pandemics: a severity-based cost effectiveness analysis.

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Kelso, Joel K; Halder, Nilimesh; Milne, George J

2013-02-11

A critical issue in planning pandemic influenza mitigation strategies is the delay between the arrival of the pandemic in a community and the availability of an effective vaccine. The likely scenario, born out in the 2009 pandemic, is that a newly emerged influenza pandemic will have spread to most parts of the world before a vaccine matched to the pandemic strain is produced. For a severe pandemic, additional rapidly activated intervention measures will be required if high mortality rates are to be avoided. A simulation modelling study was conducted to examine the effectiveness and cost effectiveness of plausible combinations of social distancing, antiviral and vaccination interventions, assuming a delay of 6-months between arrival of an influenza pandemic and first availability of a vaccine. Three different pandemic scenarios were examined; mild, moderate and extreme, based on estimates of transmissibility and pathogenicity of the 2009, 1957 and 1918 influenza pandemics respectively. A range of different durations of social distancing were examined, and the sensitivity of the results to variation in the vaccination delay, ranging from 2 to 6 months, was analysed. Vaccination-only strategies were not cost effective for any pandemic scenario, saving few lives and incurring substantial vaccination costs. Vaccination coupled with long duration social distancing, antiviral treatment and antiviral prophylaxis was cost effective for moderate pandemics and extreme pandemics, where it saved lives while simultaneously reducing the total pandemic cost. Combined social distancing and antiviral interventions without vaccination were significantly less effective, since without vaccination a resurgence in case numbers occurred as soon as social distancing interventions were relaxed. When social distancing interventions were continued until at least the start of the vaccination campaign, attack rates and total costs were significantly lower, and increased rates of vaccination

Effective case/infection ratio of poliomyelitis in vaccinated populations.

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Bencskó, G; Ferenci, T

2016-07-01

Recent polio outbreaks in Syria and Ukraine, and isolation of poliovirus from asymptomatic carriers in Israel have raised concerns that polio might endanger Europe. We devised a model to calculate the time needed to detect the first case should the disease be imported into Europe, taking the effect of vaccine coverage - both from inactivated and oral polio vaccines, also considering their differences - on the length of silent transmission into account by deriving an 'effective' case/infection ratio that is applicable for vaccinated populations. Using vaccine coverage data and the newly developed model, the relationship between this ratio and vaccine coverage is derived theoretically and is also numerically determined for European countries. This shows that unnoticed transmission is longer for countries with higher vaccine coverage and a higher proportion of IPV-vaccinated individuals among those vaccinated. Assuming borderline transmission (R = 1·1), the expected time to detect the first case is between 326 days and 512 days in different countries, with the number of infected individuals between 235 and 1439. Imperfect surveillance further increases these numbers, especially the number of infected until detection. While longer silent transmission does not increase the number of clinical diseases, it can make the application of traditional outbreak response methods more complicated, among others.

Twenty years of universal vaccination against hepatitis B in Italy: achievements and challanges

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Luisa Romano'

2012-04-01

Full Text Available Viral hepatitis B is a vaccine-preventable disease. Vaccination has proved to be safe and highly effective in reducing the incidence, the carrier rate and HBV-related mortality on a global scale. In Italy, universal vaccination against hepatitis B started in 1991 in infants as well as in adolescents, providing an outstanding record of safety and effectiveness. Within a few years, over 95% coverage was consistently reported. Today, some 17 million people are immune against hepatitis B and their immunity has been shown to be long-lasting. At present, no booster is required in healthy vaccinated people to sustain protection. Surveillance data from Italy have shown a clear overall decline in hepatitis B among successfully vaccinated individuals. Furthermore, a generation of children and young people (at present cohorts ranging from 0 to 32 years is emerging with practically no markers of HBV infection. Italy’s vaccination programme has resulted in substantial progress being made towards the prevention and control of hepatitis B. The vaccination programme must continue. Maintaining mandatory vaccination of infants and increasing HBV vaccination coverage in high-risk groups, including households of HBsAg carriers as well as immigrants, remain a priority for the future.

An E2-Substituted Chimeric Pestivirus With DIVA Vaccine Properties

DEFF Research Database (Denmark)

Rasmussen, Thomas Bruun; Uttenthal, Åse; Nielsen, Jens

An advantage of the use of chimeric pestiviruses as modified live vaccines against classical swine fever (CSF) resides in their capacity to be manipulated to achieve the characteristics desired for safe and efficacious DIVA vaccines. We have recently generated a new chimeric virus, Riems26_E2gif...... vaccinated pigs were protected. This new chimeric pestivirus represents a C-strain based DIVA vaccine candidate that can be differentiated based on CSFV E2 specific antibodies....

[Adverse effects of seasonal flu vaccine and new influenza A (H1N1) vaccine in health care workers].

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Torruella, Joan Inglés; Soto, Rosa Gil; Valls, Rosa Carreras; Lozano, Judit Valverde; Carreras, Dolors Benito; Cunillera, Arnau Besora

2013-01-01

To assess and compare adverse effects of Seasonal Influenza Vaccine (SIV) and new Influenza A(H1N1) Vaccine (AIV) in health care workers. Multicenter cross-sectional study in health care workers from acute care hospitals, primary health care centers, social centers, mental health centers and a geriatric hospital participating in the 2009 vaccination campaign. Self-administered questionnaires were sent to all workers vaccinated with SIV and/or AIV. 527 valid questionnaires were collected out of 1123 sent to SIV vaccinated workers (46.9%), and 241 out of 461 sent to AIV vaccinated workers (52.%%). Participant workers include 527 vaccinated only with SIV, 117 first vaccinated with SIV and later with AIV (SIV+AIV), and 125 vaccinated only with AIV. Overall, 18.4% (95%CI 15.1-21.7) of workers vaccinated only with SIV reported adverse effects, as compared to 45.3% (95I 36.3-54.3) reporting adverse effects to AIV in the SIV+AIV group and 46.4% (95%CI 37.7-55.1) of workers vaccinated only with AIV. In all participants the most common adverseeffect was a local reaction. Women wre more reactive to both SIV and AIV than men. In all age groups SIV vaccination alone caused fewer reactions that either AIV only or the combination of SIV+AIV, with the exception of workers below 29 years of age. AIV was associated with more reactions than SIV, with no differences observed in relation to administration sequence. There were differences by sex and age, but reactions always occurred more commonly with AIV. Copyright belongs to the Societat Catalana de Seguretat i Medicina del Treball.

Cost-effectiveness of quadrivalent human papillomavirus vaccination in adolescent girls

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A. V. Rudakova

2016-01-01

Full Text Available The human papillomavirus (HPV infection is one of the major risk factor of development of genital warts, a cervical dysplasia, a cervical cancer, and also some other oncologic diseases. The usage of quadrivalent HPV vaccine in girls reduces the corresponding case rate and the mortality significantly.The objective of this study is to analyze the cost-effectiveness of quadrivalent HPV vaccination cases of 12-yearold girls in Russian Federation.Materials and methods. A Markov model is used on the basis of epidemiological data in Russian Federation. The cost-effectiveness was estimated from societal perspective. We assumed that the effect of vaccination remains throughout all life. The analysis is performed for survival of 12-year-old girls. We considered only effect in the vaccinated population. Costs for therapy of the diseases associated with HPV infection corresponded to compulsory health insurance rates across St. Petersburg for 2016. Costs and life expectancy have been discounted for 3,5% a year.Results. Quadrivalent HPV vaccination of 12-year-old girls in Russian Federation will allow to prevent counting on 10000 the vaccinated persons 293 cases of genital warts, 15 cases of pre invasive cervical cancer, 81 cases of invasive cervical cancer, 6 cases of vulvar cancer, 2 cases of vaginal cancer, 2 cases of anal cancer, 1 case of oropharyngeal cancer. In general, 49 cases of death caused by HPV infection on 10000 vaccinated girls would be prevented. The vaccination will provide cost reduction, caused by HPV-associated diseases, for 68% (58,38 million rubles on 10000 vaccinated, and 96% of the predicted prevented costs will be caused by decrease in incidence of cervical cancer. The quadrivalent HPV vaccination is associated with an incremental cost-effectiveness ratio (ICER of 172 000 rubles per quality adjusted life-year (QALY and 411 300 rubles per death caused by HPV-associated diseases.Conclusions. Quadrivalent

Randomized controlled trials for influenza drugs and vaccines: a review of controlled human infection studies

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Shobana Balasingam

2016-08-01

Conclusions: Controlled human infection studies are an important research tool in assessing promising influenza vaccines and antivirals. These studies are performed quickly and are cost-effective and safe, with a low incidence of serious adverse events.

Effectiveness of rotavirus vaccines against hospitalisations in Japan.

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Fujii, Yoshiyuki; Noguchi, Atsuko; Miura, Shinobu; Ishii, Haruka; Nakagomi, Toyoko; Nakagomi, Osamu; Takahashi, Tsutomu

2017-07-11

In Japan, rotavirus hospitalisation occurs at a rate from 2.8 to 13.7 per 1000 child-years among children age less than 5 years, and it imposes a substantial burden to the healthcare system in the country. While both monovalent (RV1) and pentavalent (RV5) rotavirus vaccines are licensed in Japan, neither has been incorporated in the national infant immunization programme. In this study, we estimated vaccine effectiveness (VE) in Japan. This study was conducted in Yuri-Kumiai General Hospital located in a city in the north-western part of Japan. Age-eligible children for rotavirus vaccination were enrolled if they were hospitalized for rotavirus gastroenteritis between September 2013 and August 2016. Rotavirus gastroenteritis was defined by the detection of rotavirus antigen by immunochromatography. "Vaccinated" was defined as infant inoculated with at least one dose of either RV1 or RV5. A conditional logistic regression analysis was performed by modelling the year of birth, year of admission, residence of the children and vaccination status, and by matching the age of cases with that of test-negative controls. The adjusted odds ratio of the vaccinated over unvaccinated was then used to calculate VE in the formula of (1 - adjusted odds ratio) × 100. Out of the 244 patients enrolled, rotavirus antigen was detected in 55 (22.5%) of whom 10 (18.2%) were vaccinated, whereas 94 (49.7%) of 189 test-negative controls were vaccinated. During the study period, the vaccine uptake rate in the controls increased from 36.2% to 61.8%. On the other hand, the vaccination coverage over the three years was 64.2% in Yuri-Honjo city (three quarters of the catchment), and 91.4% in Nikaho city (one quarter of the catchment). The VE was calculated to be 70.4% (95% confidence interval: 36.0-86.4%, P = 0.002). The point estimate of the VE was lower but its 95% confidence interval overlaps those of the efficacies obtained from clinical trials in Japan. The rotavirus vaccine was

Marketing paediatric influenza vaccination: results of a major metropolitan trial.

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Van Buynder, Paul G; Carcione, Dale; Rettura, Vince; Daly, Alison; Woods, Emily

2011-01-01

After a cluster of rapidly fulminant influenza related toddler deaths in a Western Australian metropolis, children aged six to 59 months were offered influenza vaccination in subsequent winters. Some parental resistance was expected and previous poor uptake of paediatric influenza vaccination overseas was noted. A marketing campaign addressing barriers to immunization was developed to maximise uptake. Advertising occurred in major statewide newspapers, via public poster displays and static 'eye-lite' displays, via press releases, via a series of rolling radio advertisements, via direct marketing to child care centres, and via a linked series of web-sites. Parents were subsequently surveyed to assess reasons for vaccination. The campaign produced influenza vaccination coverage above that previously described elsewhere and led to a proportionate reduction in influenza notifications in this age group compared to previous seasons. Influenza in children comes with significant morbidity and some mortality. Paediatric influenza vaccination is safe, well tolerated and effective if two doses are given. A targeted media campaign can increase vaccine uptake if it reinforces the seriousness of influenza and addresses community 'myths' about influenza and influenza vaccine. The lessons learned enabling enhancements of similar programs elsewhere. © 2010 Blackwell Publishing Ltd.

Overview of Vaccine Adjuvants: Introduction, History, and Current Status.

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Shah, Ruchi R; Hassett, Kimberly J; Brito, Luis A

2017-01-01

Adjuvants are included in sub-unit or recombinant vaccines to enhance the potency of poorly immunogenic antigens. Adjuvant discovery is as complex as it is a multidiscplinary intersection of formulation science, immunology, toxicology, and biology. Adjuvants such as alum, which have been in use for the past 90 years, have illustrated that adjuvant research is a methodical process. As science advances, new analytical tools are developed which allows us to delve deeper into the various mechanisms that generates a potent immune response. Additionally, these new techniques help the field learn about our existing vaccines and what makes them safe, and effective, allowing us to leverage that in the next generation of vaccines. Our goal in this chapter is to define the concept, need, and mechanism of adjuvants in the vaccine field while describing its history, present use, and future prospects. More details on individual adjuvants and their formulation, development, mechanism, and use will be covered in depth in the next chapters.

Immune responses to the smallpox vaccine given in combination with ST-246, a small-molecule inhibitor of poxvirus dissemination

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Grosenbach, Douglas W.; Jordan, Robert; King, David S.; Berhanu, Aklile; Warren, Travis K.; Kirkwood-Watts, Dana L.; Tyavanagimatt, Shanthakumar; Tan, Ying; Wilson, Rebecca L.; Jones, Kevin F.; Hruby, Dennis E.

2007-01-01

The re-emerging threat of smallpox and the emerging threat of monkeypox highlight the need for effective poxvirus countermeasures. Currently approved smallpox vaccines have unacceptable safety profiles and, consequently, the general populace is no longer vaccinated, leading to an increasingly susceptible population. ST-246, a small-molecule inhibitor of poxvirus dissemination, has been demonstrated in various animal models to be safe and effective in preventing poxviral disease. This suggests...

Typhoid Fever surveillance and vaccine use - South-East Asia and Western Pacific regions, 2009-2013.

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Date, Kashmira A; Bentsi-Enchill, Adwoa D; Fox, Kimberley K; Abeysinghe, Nihal; Mintz, Eric D; Khan, M Imran; Sahastrabuddhe, Sushant; Hyde, Terri B

2014-10-03

Typhoid fever is a serious, systemic infection resulting in nearly 22 million cases and 216,500 deaths annually, primarily in Asia. Safe water, adequate sanitation, appropriate personal and food hygiene, and vaccination are the most effective strategies for prevention and control. In 2008, the World Health Organization (WHO) recommended use of available typhoid vaccines to control endemic disease and outbreaks and strengthening of typhoid surveillance to improve disease estimates and identify high-risk populations (e.g., persons without access to potable water and adequate sanitation). This report summarizes the status of typhoid surveillance and vaccination programs in the WHO South-East Asia (SEAR) and Western Pacific regions (WPR) during 2009-2013, after the revised WHO recommendations. Data were obtained from the WHO/United Nations Children's Fund (UNICEF) Joint Reporting Form on Immunization, a supplemental survey of surveillance and immunization program managers, and published literature. During 2009-2013, 23 (48%) of 48 countries and areas of SEAR (11) and WPR (37) collected surveillance or notifiable disease data on typhoid cases, with most surveillance activities established before 2008. Nine (19%) countries reported implementation of typhoid vaccination programs or recommended vaccine use during 2009-2013. Despite the high incidence, typhoid surveillance is weak in these two regions, and vaccination efforts have been limited. Further progress toward typhoid fever prevention and control in SEAR and WPR will require country commitment and international support for enhanced surveillance, targeted use of existing vaccines and availability of newer vaccines integrated within routine immunization programs, and integration of vaccination with safe water, sanitation, and hygiene measures.

Genotyping assay for differentiation of wild-type and vaccine viruses in subjects immunized with live attenuated influenza vaccine.

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Victoria Matyushenko

Full Text Available Live attenuated influenza vaccines (LAIVs are considered as safe and effective tool to control influenza in different age groups, especially in young children. An important part of the LAIV safety evaluation is the detection of vaccine virus replication in the nasopharynx of the vaccinees, with special attention to a potential virus transmission to the unvaccinated close contacts. Conducting LAIV clinical trials in some geographical regions with year-round circulation of influenza viruses warrants the development of robust and reliable tools for differentiating vaccine viruses from wild-type influenza viruses in nasal pharyngeal wash (NPW specimens of vaccinated subjects. Here we report the development of genotyping assay for the detection of wild-type and vaccine-type influenza virus genes in NPW specimens of young children immunized with Russian-backbone seasonal trivalent LAIV using Sanger sequencing from newly designed universal primers. The new primer set allowed amplification and sequencing of short fragments of viral genes in NPW specimens and appeared to be more sensitive than conventional real-time RT-PCR protocols routinely used for the detection and typing/subtyping of influenza virus in humans. Furthermore, the new assay is capable of defining the origin of wild-type influenza virus through BLAST search with the generated sequences of viral genes fragments.

Imperfect Vaccine Aggravates the Long-Standing Dilemma of Voluntary Vaccination

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Wu, Bin; Fu, Feng; Wang, Long

2011-01-01

Achieving widespread population immunity by voluntary vaccination poses a major challenge for public health administration and practice. The situation is complicated even more by imperfect vaccines. How the vaccine efficacy affects individuals' vaccination behavior has yet to be fully answered. To address this issue, we combine a simple yet effective game theoretic model of vaccination behavior with an epidemiological process. Our analysis shows that, in a population of self-interested individuals, there exists an overshooting of vaccine uptake levels as the effectiveness of vaccination increases. Moreover, when the basic reproductive number, , exceeds a certain threshold, all individuals opt for vaccination for an intermediate region of vaccine efficacy. We further show that increasing effectiveness of vaccination always increases the number of effectively vaccinated individuals and therefore attenuates the epidemic strain. The results suggest that ‘number is traded for efficiency’: although increases in vaccination effectiveness lead to uptake drops due to free-riding effects, the impact of the epidemic can be better mitigated. PMID:21687680

Imperfect vaccine aggravates the long-standing dilemma of voluntary vaccination.

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Bin Wu

Full Text Available Achieving widespread population immunity by voluntary vaccination poses a major challenge for public health administration and practice. The situation is complicated even more by imperfect vaccines. How the vaccine efficacy affects individuals' vaccination behavior has yet to be fully answered. To address this issue, we combine a simple yet effective game theoretic model of vaccination behavior with an epidemiological process. Our analysis shows that, in a population of self-interested individuals, there exists an overshooting of vaccine uptake levels as the effectiveness of vaccination increases. Moreover, when the basic reproductive number, R0, exceeds a certain threshold, all individuals opt for vaccination for an intermediate region of vaccine efficacy. We further show that increasing effectiveness of vaccination always increases the number of effectively vaccinated individuals and therefore attenuates the epidemic strain. The results suggest that 'number is traded for efficiency': although increases in vaccination effectiveness lead to uptake drops due to free-riding effects, the impact of the epidemic can be better mitigated.

Immunology and evolvement of the adenovirus prime, MVA boost Ebola virus vaccine.

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Zhou, Yan; Sullivan, Nancy J

2015-08-01

The 2014 Ebola virus outbreak caused an order of magnitude more deaths in a single outbreak than all previous known outbreaks combined, affecting both local and international public health, and threatening the security and economic stability of the countries in West Africa directly confronting the outbreak. The severity of the epidemic lead to a global response to assist with patient care, outbreak control, and deployment of vaccines. The latter was possible due to the long history of basic and clinical research aimed at identifying a safe and effective vaccine to protect against Ebola virus infection. This review highlights the immunology, development, and progress of vaccines based on replication-defective adenovirus vectors, culminating in the successful launch of the first Phase III trial of an Ebola virus vaccine. Published by Elsevier Ltd.

Toward a new generation of vaccines: the anti-cytokine therapeutic vaccines.

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Zagury, D; Burny, A; Gallo, R C

2001-07-03

Pathological conditions, such as cancers, viral infections, and autoimmune diseases, are associated with abnormal cytokine production, and the morbidity associated with many medical disorders is often directly a result of cytokine production. Because of the absence of negative feedback control occurring in some pathophysiologic situations, a given cytokine may flood and accumulate in the extracellular compartment of tissues or tumors thereby impairing the cytokine network homeostasis and contributing to local pathogenesis. To evaluate whether the rise of anti-cytokine Abs by vaccination is an effective way to treat these pathological conditions without being harmful to the organism, we have analyzed each step of the cytokine process (involving cytokine production, target response, and feedback regulation) and have considered them in the local context of effector--target cell microenvironment and in the overall context of the macroenvironment of the immune system of the organism. In pathologic tissues, Abs of high affinity, as raised by anti-cytokine vaccination, should neutralize the pool of cytokines ectopically accumulated in the extracellular compartment, thus counteracting their pathogenic effects. In contrast, the same Abs should not interfere with cytokine processes occurring in normal tissues, because under physiologic conditions cytokine production by effector cells (induced by activation but controlled by negative feedback regulation) does not accumulate in the extracellular compartment. These concepts are consistent with results showing that following animal and human anti-cytokine vaccination, induction of high-affinity Abs has proven to be safe and effective and encourages this approach as a pioneering avenue of therapy.

VACCINATION OF CHILDREN WITH MALIGNANCIES

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D.Yu. Kachanov

2010-01-01

Full Text Available Children suffering from oncological diseases fall into the group of immunocompromised patients. They are more at risk of severe children’s banal infections. Development of safe and efficient methods for immunological prevention of preventable infections diseases in this group of children is one of priorities for modern medicine. It is also important to properly organise the process of vaccinating the persons surrounding the patient to eliminate the risk of postvaccinal complications in the sick (non-vaccinated child. The article provides a detailed overview of the global experience in vaccinating children with malignant neoplasms. It describes modern principles of immunological prevention in children both being administered the standard anticancer therapy and those have undergone transplantation of hemopoietic stem cells. Key words: children, malignancy, vaccination.(Pediatric Pharmacology. – 2010; 7(3:28-34

Prevention of carcinoma of cervix with human papillomavirus vaccine.

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Gavarasana, S; Kalasapudi, R S; Rao, T D; Thirumala, S

2000-01-01

Carcinoma of cervix is the most common cancer found among the women of India. Though cervical cytology screening was effective in preventing carcinoma of cervix in developed nations, it is considered unsuitable in developing countries. Recent research has established an etiological link between human papillomavirus infection and carcinoma of cervix. In this review, an attempt is made to answer the question, 'whether carcinoma of cervix can be prevented with human papillomavirus vaccine?' Literature search using Pubmed and Medline was carried out and relevant articles were reviewed. There is ample experimental evidence to show that DNA of human papillomavirus integrates with cervical cell genome. Viral genes E6 and E7 of HPV type 16 and 18 inactivate p53 function and Rb gene, thus immortalize the cervical epithelial cells. Recombinant vaccines blocked the function of E6 and E7 genes preventing development of papillomas in animals. Vaccination with HPV-VLPs encoding for genes of E6 and E7 neutralizes HPV integrated genome of malignant cells of uterine cervix. Based on experimental evidence, it is possible to prevent carcinoma of cervix with human papillomavirus vaccine, Further research is necessary to identify a effective and safe HPV vaccine, routes of administration and characteristics of potential beneficiaries.

Socio-psychological factors driving adult vaccination: a qualitative study.

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Ana Wheelock

Full Text Available While immunization is one of the most effective and successful public health interventions, there are still up to 30,000 deaths in major developed economies each year due to vaccine-preventable diseases, almost all in adults. In the UK, despite comparatively high vaccination rates among ≥65 s (73% and, to a lesser extent, at-risk ≤65 s (52% in 2013/2014, over 10,000 excess deaths were reported the previous influenza season. Adult tetanus vaccines are not routinely recommended in the UK, but may be overly administered. Social influences and risk-perceptions of diseases and vaccines are known to affect vaccine uptake. We aimed to explore the socio-psychological factors that drive adult vaccination in the UK, specifically influenza and tetanus, and to evaluate whether these factors are comparable between vaccines.20 in-depth, face-to-face interviews were conducted with members of the UK public who represented a range of socio-demographic characteristics associated with vaccination uptake. We employed qualitative interviewing approaches to reach a comprehensive understanding of the factors influencing adult vaccination decisions. Thematic analysis was used to analyze the data.Participants were classified according to their vaccination status as regular, intermittent and non-vaccinators for influenza, and preventative, injury-led, mixed (both preventative and injury-led and as non-vaccinators for tetanus. We present our finding around five overarching themes: 1 perceived health and health behaviors; 2 knowledge; 3 vaccination influences; 4 disease appraisal; and 5 vaccination appraisal.The uptake of influenza and tetanus vaccines was largely driven by participants' risk perception of these diseases. The tetanus vaccine is perceived as safe and sufficiently tested, whereas the changing composition of the influenza vaccine is a cause of uncertainty and distrust. To maximize the public health impact of adult vaccines, policy should be better

Safety and long-term immunological effects of CryJ2-LAMP plasmid vaccine in Japanese red cedar atopic subjects: A phase I study.

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Su, Yan; Romeu-Bonilla, Eliezer; Anagnostou, Athanasia; Fitz-Patrick, David; Hearl, William; Heiland, Teri

2017-12-02

Japanese Red Cedar (JRC) pollen induced allergy affects one third of Japanese and the development of effective therapies remains an unachieved challenge. We designed a DNA vaccine encoding CryJ2 allergen from the JRC pollen and Lysosomal Associated Membrane Protein 1 (LAMP-1) to treat JRC allergy. These Phase IA and IB trials assessed safety and immunological effects of the investigational CryJ2-LAMP DNA vaccine in both non-sensitive and sensitive Japanese expatriates living in Honolulu, Hawaii. In the Phase IA trial, 6 JRC non-sensitive subjects and 9 JRC and/or Mountain Cedar (MC) sensitive subjects were given 4 vaccine doses (each 4mg/1ml) intramuscularly (IM) at 14-day intervals. Nine JRC and/or MC sensitive subjects were given 4 doses (2 mg/0.5 ml) IM at 14-day intervals. The safety and functional biomarkers were followed for 132 d. Following this, 17 of 24 subjects were recruited into the IB trial and received one booster dose (2 mg/0.5 ml) IM approximately 300 d after the first vaccination dose to which they were randomized in the first phase of the trial. All safety endpoints were met and all subjects tolerated CryJ2-LAMP vaccinations well. At the end of the IA trial, 10 out of 12 JRC sensitive and 6 out of 11 MC sensitive subjects experienced skin test negative conversion, possibly related to the CryJ2-LAMP vaccinations. Collectively, these data suggested that the CryJ2-LAMP DNA vaccine is safe and may be immunologically effective in treating JRC induced allergy.

Non-clinical efficacy and safety of HyVac4:IC31 vaccine administered in a BCG prime-boost regimen.

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Skeiky, Yasir A W; Dietrich, Jes; Lasco, Todd M; Stagliano, Katherine; Dheenadhayalan, Veerabadran; Goetz, Margaret Ann; Cantarero, Luis; Basaraba, Randall J; Bang, Peter; Kromann, Ingrid; McMclain, J Bruce; Sadoff, Jerald C; Andersen, Peter

2010-01-22

Despite the extensive success with the introduction of M. bovis Bacille Calmette-Guérin (BCG), tuberculosis (TB) remains a major global epidemic infecting between 8 and 9 million people annually with an estimated 1.7 million deaths each year. However, because of its demonstrated effectiveness against some of the most severe forms of childhood TB, it is now realized that BCG vaccination of newborns is unlikely to be replaced. Therefore, BCG or an improved BCG will continue to be used as a prime TB vaccine and there is a need to develop effective boost vaccines that would enhance and prolong the protective immunity induced by BCG prime immunization. We report on a heterologous booster approach using two highly immunogenic TB antigens comprising Ag85B and TB10.4 (HyVac4) delivered as a fusion molecule and formulated in the proprietary adjuvant IC31. This vaccine was found to be immunogenic and demonstrated greater protection in the more stringent guinea pig model of pulmonary tuberculosis than BCG alone when used in a prime/boost regimen. Significant difference in lung involvement was observed for all animals in the HyVac4 boosted group compared to BCG alone regardless of time to death or sacrifice. A vaccine toxicology study of the HyVac4:IC31 regimen was performed and it was judged safe to advance the vaccine into clinical trials. Therefore, all non-clinical data supports the suitability of HyVac4 as a safe, immunogenic, and effective vaccination in a prime-boost regimen with BCG.

Sub-nucleocapsid nanoparticles: a nasal vaccine against respiratory syncytial virus.

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Xavier Roux

Full Text Available BACKGROUND: Bronchiolitis caused by the respiratory syncytial virus (RSV in infants less than two years old is a growing public health concern worldwide, and there is currently no safe and effective vaccine. A major component of RSV nucleocapsid, the nucleoprotein (N, has been so far poorly explored as a potential vaccine antigen, even though it is a target of protective anti-viral T cell responses and is remarkably conserved between human RSV A and B serotypes. We recently reported a method to produce recombinant N assembling in homogenous rings composed of 10-11 N subunits enclosing a bacterial RNA. These nanoparticles were named sub-nucleocapsid ring structure (N SRS. METHODOLOGY AND PRINCIPAL FINDINGS: The vaccine potential of N SRS was evaluated in a well-characterized and widely acknowledged mouse model of RSV infection. BALB/c adult mice were immunized intranasally with N SRS adjuvanted with the detoxified E. coli enterotoxin LT(R192G. Upon RSV challenge, vaccinated mice were largely protected against virus replication in the lungs, with a mild inflammatory lymphocytic and neutrophilic reaction in their airways. Mucosal immunization with N SRS elicited strong local and systemic immunity characterized by high titers of IgG1, IgG2a and IgA anti-N antibodies, antigen-specific CD8(+ T cells and IFN-gamma-producing CD4(+ T cells. CONCLUSIONS/SIGNIFICANCE: This is the first report of using nanoparticles formed by the recombinant nucleocapsid protein as an efficient and safe intra-nasal vaccine against RSV.

An assessment of mumps vaccine effectiveness by dose during an outbreak in Canada.

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Deeks, Shelley L; Lim, Gillian H; Simpson, Mary Anne; Gagné, Louise; Gubbay, Jonathan; Kristjanson, Erik; Fung, Cecilia; Crowcroft, Natasha S

2011-06-14

This investigation was done to assess vaccine effectiveness of one and two doses of the measles, mumps and rubella (MMR) vaccine during an outbreak of mumps in Ontario. The level of coverage required to reach herd immunity and interrupt community transmission of mumps was also estimated. Information on confirmed cases of mumps was retrieved from Ontario's integrated Public Health Information System. Cases that occurred between Sept. 1, 2009, and June 10, 2010, were included. Selected health units supplied coverage data from the Ontario Immunization Record Information System. Vaccine effectiveness by dose was calculated using the screening method. The basic reproductive number (R(0)) represents the average number of new infections per case in a fully susceptible population, and R(0) values of between 4 and 10 were considered for varying levels of vaccine effectiveness. A total of 134 confirmed cases of mumps were identified. Information on receipt of MMR vaccine was available for 114 (85.1%) cases, of whom 63 (55.3%) reported having received only one dose of vaccine; 32 (28.1%) reported having received two doses. Vaccine effectiveness of one dose of the MMR vaccine ranged from 49.2% to 81.6%, whereas vaccine effectiveness of two doses ranged from 66.3% to 88.0%. If we assume vaccine effectiveness of 85% for two doses of the vaccine, vaccine coverage of 88.2% and 98.0% would be needed to interrupt community transmission of mumps if the corresponding reproductive values were four and six. Our estimates of vaccine effectiveness of one and two doses of mumps-containing vaccine were consistent with the estimates that have been reported in other outbreaks. Outbreaks occurring in Ontario and elsewhere serve as a warning against complacency over vaccination programs.

Cost-effectiveness analysis of pneumococcal vaccination for infants in China.

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Maurer, Kristin A; Chen, Huey-Fen; Wagner, Abram L; Hegde, Sonia T; Patel, Tejasi; Boulton, Matthew L; Hutton, David W

2016-12-07

Although China has a high burden of pneumococcal disease among young children, the government does not administer publicly-funded pneumococcal conjugate vaccines (PCV) through its Expanded Program on Immunization (EPI). We evaluated the cost-effectiveness of publicly-funded PCV-7, PCV-10, and PCV-13 vaccination programs for infants in China. Using a Markov model, we simulated a cohort of 16 million Chinese infants to estimate the impact of PCV-7, PCV-10, and PCV-13 vaccination programs from a societal perspective. We extrapolated health states to estimate the effects of the programs over the course of a lifetime of 75years. Parameters in the model were derived from a review of the literature. We found that PCV-7, PCV-10, and PCV-13 vaccination programs would be cost-effective compared to no vaccination. However, PCV-13 had the lowest incremental cost-effectiveness ratio ($11,464/QALY vs $16,664/QALY for PCV-10 and $18,224/QALY for PCV-7) due to a reduction in overall costs. Our sensitivity analysis revealed that the incremental cost-effectiveness ratios were most sensitive to the utility of acute otitis media, the cost of PCV-13, and the incidence of pneumonia and acute otitis media. The Chinese government should take steps to reduce the burden of pneumococcal diseases among young children through the inclusion of a pneumococcal conjugate vaccine in its EPI. Although all vaccinations would be cost-effective, PCV-13 would save more costs to the healthcare system and would be the preferred strategy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measuring effectiveness of the cervical cancer vaccine in an Australian setting (the VACCINE study).

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Young, Elisa J; Tabrizi, Sepehr N; Brotherton, Julia Ml; Wark, John D; Pyman, Jan; Saville, Marion; Wrede, C David; Jayasinghe, Yasmin; Tan, Jeffrey; Gertig, Dorota M; Pitts, Marian; Garland, Suzanne M

2013-06-19

The quadrivalent human papillomavirus vaccine has been provided in Australia through the National Human Papillomavirus Vaccination Program since April 2007. National registry data demonstrates good coverage of the vaccine, with 73% of school-aged girls having received all three doses. To evaluate the effectiveness of the program, we propose a two-pronged approach. In one (sub study A), the prevalence of the vaccine-targeted human papillomavirus genotypes in a population cohort is being estimated, and will be analysed in relation to vaccination status, cervical cytology screening status, demographic, social, behavioural, medical and clinical factors. In sub study B, the distribution of human papillomavirus genotypes detected in high grade cervical intraepithelial neoplastic lesions from vaccine eligible women is being assessed. Sub Study A involves the recruitment of 1569 women aged 18-25, residing in Victoria, Australia, through Facebook advertising. Women who are sexually active are being asked to provide a self-collected vaginal swab, collected at home and posted into the study centre, where human papillomavirus DNA detection and genotyping is performed. Participants also complete an online questionnaire regarding sexual history, experience with, knowledge of, and attitudes towards human papillomavirus, the human papillomavirus vaccine, and cervical screening.Sub Study B will involve the collection of 500 cervical biopsies, positively identified as containing high grade cervical intraepithelial neoplastic lesions and/or adenocarcinoma in situ. Five serial sections are being taken from each case: sections 1 and 5 are being assessed to confirm the presence of the high grade cervical intraepithelial neoplastic lesions or adenocarcinoma in situ; human papillomavirus genotyping is performed on sections 2 and 3; single lesions are excised from section 4 using laser capture microdissection to specifically define causality of a human papillomavirus genotyping of each

Cost-effectiveness of 13-valent pneumococcal conjugate vaccination in Mongolia.

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Sundaram, Neisha; Chen, Cynthia; Yoong, Joanne; Luvsan, Munkh-Erdene; Fox, Kimberley; Sarankhuu, Amarzaya; La Vincente, Sophie; Jit, Mark

2017-02-15

The Ministry of Health (MOH), Mongolia, is considering introducing 13-valent pneumococcal conjugate vaccine (PCV13) in its national immunization programme to prevent the burden of disease caused by Streptococcus pneumoniae. This study evaluates the cost-effectiveness and budget impact of introducing PCV13 compared to no PCV vaccination in Mongolia. The incremental cost-effectiveness ratio (ICER) of introducing PCV13 compared to no PCV vaccination was assessed using an age-stratified static multiple cohort model. The risk of various clinical presentations of pneumococcal disease (meningitis, pneumonia, non-meningitis non-pneumonia invasive pneumococcal disease and acute otitis media) at all ages for thirty birth cohorts was assessed. The analysis considered both health system and societal perspectives. A 3+0 vaccine schedule and price of US$3.30 per dose was assumed for the baseline scenario based on Gavi, the Vaccine Alliance's advance market commitment tail price. The ICER of PCV13 introduction is estimated at US$52 per disability-adjusted life year (DALY) averted (health system perspective), and cost-saving (societal perspective). Although indirect effects of PCV have been well-documented, a conservative scenario that does not consider indirect effects estimated PCV13 introduction to cost US$79 per DALY averted (health system perspective), and US$19 per DALY averted (societal perspective). Vaccination with PCV13 is expected to cost around US$920,000 in 2016, and thereafter US$820,000 every year. The programme is likely to reduce direct disease-related costs to MOH by US$440,000 in the first year, increasing to US$510,000 by 2025. Introducing PCV13 as part of Mongolia's national programme appears to be highly cost-effective when compared to no vaccination and cost-saving from a societal perspective at vaccine purchase prices offered through Gavi. Notwithstanding uncertainties around some parameters, cost-effectiveness of PCV introduction for Mongolia remains

Regulatory T cell frequencies and phenotypes following anti-viral vaccination.

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A Charlotte M T de Wolf

Full Text Available Regulatory T cells (Treg function in the prevention of excessive inflammation and maintenance of immunological homeostasis. However, these cells may also interfere with resolution of infections or with immune reactions following vaccination. Effects of Treg on vaccine responses are nowadays investigated, but the impact of vaccination on Treg homeostasis is still largely unknown. This may be a relevant safety aspect, since loss of tolerance through reduced Treg may trigger autoimmunity. In exploratory clinical trials, healthy adults were vaccinated with an influenza subunit vaccine plus or minus the adjuvant MF59®, an adjuvanted hepatitis B subunit vaccine or a live attenuated yellow fever vaccine. Frequencies and phenotypes of resting (rTreg and activated (aTreg subpopulations of circulating CD4+ Treg were determined and compared to placebo immunization. Vaccination with influenza vaccines did not result in significant changes in Treg frequencies and phenotypes. Vaccination with the hepatitis B vaccine led to slightly increased frequencies of both rTreg and aTreg subpopulations and a decrease in expression of functionality marker CD39 on aTreg. The live attenuated vaccine resulted in a decrease in rTreg frequency, and an increase in expression of activation marker CD25 on both subpopulations, possibly indicating a conversion from resting to migratory aTreg due to vaccine virus replication. To study the more local effects of vaccination on Treg in lymphoid organs, we immunized mice and analyzed the CD4+ Treg frequency and phenotype in draining lymph nodes and spleen. Vaccination resulted in a transient local decrease in Treg frequency in lymph nodes, followed by a systemic Treg increase in the spleen. Taken together, we showed that vaccination with vaccines with an already established safe profile have only minimal impact on frequencies and characteristics of Treg over time. These findings may serve as a bench-mark of inter-individual variation

Yellow fever vaccine-associated neurotropic disease (YEL-AND) - A case report.

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Florczak-Wyspiańska, Jolanta; Nawotczyńska, Ewa; Kozubski, Wojciech

Yellow fever (YF) is a mosquito-borne viral hemorrhagic fever, which is a serious and potentially fatal disease with no specific antiviral treatment that can be effectively prevented by an attenuated vaccine (YEL). Despite the long history of safe and efficacious YF vaccination, sporadic case reports of serious adverse events (SAEs) have been reported, including yellow fever vaccine-associated neurotropic disease (YEL-AND). YEL-AND usually appears within one month of YF vaccination, manifesting as meningoencephalitis, Guillain-Barré syndrome (GBS) or acute disseminated encephalomyelitis (ADEM). We report a case of YEL-AND with meningitis presentation in a 39-year-old Caucasian man without evidence of significant risk factors, which was confirmed by the presence of the YF virus and specific immunoglobulin G (IgG) antibodies in the cerebrospinal fluid (CSF). In conclusion, we should stress the importance of balancing the risk of SAEs associated with the vaccine and the benefits of YF vaccination for each patient individually. Copyright © 2016 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Rotavirus vaccine and diarrhea mortality: quantifying regional variation in effect size

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Fischer Walker, Christa L; Black, Robert E

2011-01-01

Abstract Background Diarrhea mortality remains a leading cause of child death and rotavirus vaccine an effective tool for preventing severe rotavirus diarrhea. New data suggest vaccine efficacy may vary by region. Methods We reviewed published vaccine efficacy trials to estimate a regional-specific effect of vaccine efficacy on severe rotavirus diarrhea and hospitalizations. We assessed the quality of evidence using a standard protocol and conducted meta-analyses where more than 1 data point ...

A cost-effectiveness analysis of typhoid fever vaccines in US military personnel.

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Warren, T A; Finder, S F; Brier, K L; Ries, A J; Weber, M P; Miller, M R; Potyk, R P; Reeves, C S; Moran, E L; Tornow, J J

1996-11-01

Typhoid fever has been a problem for military personnel throughout history. A cost-effectiveness analysis of typhoid fever vaccines from the perspective of the US military was performed. Currently 3 vaccine preparations are available in the US: an oral live Type 21A whole cell vaccine; a single-dose parenteral, cell subunit vaccine; and a 2-dose parenteral heat-phenol killed, whole cell vaccine. This analysis assumed all vaccinees were US military personnel. Two pharmacoeconomic models were developed, one for personnel who have not yet been deployed, and the other for personnel who are deployed to an area endemic for typhoid fever. Drug acquisition, administration, adverse effect and lost work costs, as well as the costs associated with typhoid fever, were included in this analysis. Unique military issues, typhoid fever attack rates, vaccine efficacy, and compliance with each vaccine's dosage regimen were included in this analysis. A sensitivity analysis was performed to test the robustness of the models. Typhoid fever immunisation is not cost-effective for US military personnel unless they are considered imminently deployable or are deployed. The most cost-effective vaccine for US military personnel is the single-dose, cell subunit parenteral vaccine.

Progress in the introduction of the rotavirus vaccine in Latin America and the Caribbean: four years of accumulated experience.

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de Oliveira, Lucia Helena; Danovaro-Holliday, M Carolina; Sanwogou, N Jennifer; Ruiz-Matus, Cuauhtemoc; Tambini, Gina; Andrus, Jon Kim

2011-01-01

Two effective and safe rotavirus vaccines became available in 2006 and have been recommended for use in all countries by the World Health Organization. This article provides an update on the use of rotavirus vaccine in Latin American and Caribbean (LAC) countries. Data reported by LAC countries to the Pan American Health Organization (PAHO) were reviewed. As of May 2010, 14 LAC countries and 1 territory have introduced the rotavirus vaccine into their national expanded program on immunization (EPI). Reported coverage levels for rotavirus vaccine are lower than those for other EPI vaccines recommended at the same age. A total of 15 LAC countries are part of the PAHO's LAC rotavirus surveillance network; 12 of them are using the vaccine. LAC countries are conducting several studies on rotavirus vaccine effectiveness, cost-effectiveness, and monitoring safety. Also, LAC countries are generating lessons learned on the public health implications of introducing a new vaccine into the EPI. Nine countries and the Cayman Islands pay for the entire cost of the vaccine using government funds. All but 2 countries purchase their rotavirus vaccine through PAHO's Revolving Fund. Rotavirus vaccine introduction in LAC has been faster than for other new vaccines, but coverage levels need to increase to maximize the effect of the intervention. Rotavirus surveillance needs to expand and be strengthened to better assess the effect of vaccine use. LAC countries will continue to provide useful data to monitor rotavirus trends and vaccine effect.

The Evolution of the Meningitis Vaccine Project.

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Tiffay, Kathleen; Jodar, Luis; Kieny, Marie-Paule; Socquet, Muriel; LaForce, F Marc

2015-11-15

In 2001, the Meningitis Vaccine Project (MVP) was tasked to develop, test, license, and introduce a group A meningococcal (MenA) conjugate vaccine for sub-Saharan Africa. African public health officials emphasized that a vaccine price of less than US$0.50 per dose was necessary to ensure introduction and sustained use of this new vaccine. Initially, MVP envisioned partnering with a multinational vaccine manufacturer, but the target price and opportunity costs were problematic and formal negotiations ended in 2002. MVP chose to become a "virtual vaccine company," and over the next decade managed a network of public-private and public-public partnerships for pharmaceutical development, clinical development, and regulatory submission. MVP supported the transfer of key know-how for the production of group A polysaccharide and a new conjugation method to the Serum Institute of India, Ltd, based in Pune, India. A robust staff structure supported by technical consultants and overseen by advisory groups in Europe and Africa ensured that the MenA conjugate vaccine would meet all international standards. A robust project structure including a team of technical consultants and 3 advisory groups in Europe and Africa ensured that the MenA conjugate vaccine (PsA-TT, MenAfriVac) was licensed by the Drug Controller General of India and prequalified by the World Health Organization in June 2010. The vaccine was introduced in Burkina Faso, Mali, and Niger in December 2010. The development, through a public-private partnership, of a safe, effective, and affordable vaccine for sub-Saharan Africa, PsA-TT, offers a new paradigm for the development of vaccines specifically targeting populations in resource-poor countries. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

Strain diversity plays no major role in the varying efficacy of rotavirus vaccines: an overview.

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Velasquez, Daniel E; Parashar, Umesh D; Jiang, Baoming

2014-12-01

While a monovalent Rotarix® [RV1] and a pentavalent RotaTeq® [RV5] have been extensively tested and found generally safe and equally efficacious in clinical trials, the question still lingers about the evolving diversity of circulating rotavirus strains over time and their relationship with protective immunity induced by rotavirus vaccines. We reviewed data from clinical trials and observational studies that assessed the efficacy or field effectiveness of rotavirus vaccines against different rotavirus strains worldwide. RV1 provided broad clinical efficacy and field effectiveness against severe diarrhea due to all major circulating strains, including the homotypic G1P[8] and the fully heterotypic G2P[4] strains. Similarly, RV5 provided broad efficacy and effectiveness against RV5 and non-RV5 strains throughout different locations. Rotavirus vaccination provides broad heterotypic protection; however continuing surveillance is needed to track the change of circulating strains and monitor the effectiveness and safety of vaccines. Published by Elsevier B.V.

Safety and immunogenicity of GMZ2 - a MSP3-GLURP fusion protein malaria vaccine candidate

DEFF Research Database (Denmark)

Esen, Meral; Kremsner, Peter G; Schleucher, Regina

2009-01-01

Malaria is a major public health problem in Sub-Saharan Africa. In highly endemic regions infants, children and pregnant women are mostly affected. An effective malaria vaccine would complement existing malaria control strategies because it can be integrated in existing immunization programs easily....... Here we present the results of the first phase Ia clinical trial of GMZ2 adjuvanted in aluminium hydroxide. GMZ2 is a malaria vaccine candidate, designed upon the rationale to induce immune responses against asexual blood stages of Plasmodium falciparum similar to those encountered in semi...... is a safe and immunogenic malaria vaccine candidate suitable for further clinical development....

[Individual versus collective protection: bioethical analysis of the national program of mass child vaccination].

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Lessa, Sérgio de Castro; Schramm, Fermin Roland

2015-01-01

Vaccination is considered one of the most efficient and cost-effective public health policies most used in the control and prevention of disease. However, it is also one of the most polemic and controversial biomedical techniques, making it difficult to avoid an ethical dilemma, especially when vaccination is compulsory for the entire population. Indeed, since vaccines are not totally effective and safe, there is an ethical conflict between the individual and the collective interest, because children effectively carry the burden of vaccination for the benefit of public health when they are affected with serious adverse reactions and do not benefit from the care that should be offered by the government. The objective of this article was to demonstrate that the tools of bioethics are relevant in this discussion to understand and analyze these dilemmas critically by providing convincing arguments to underpin the development of biopolitics that consider prevention not only rigorously, but also the joint responsibility of all as fundamental for individual and collective protection.

Biologic interactions between HSV-2 and HIV-1 and possible implications for HSV vaccine development.

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Schiffer, Joshua T; Gottlieb, Sami L

2017-09-25

Development of a safe and effective vaccine against herpes simplex virus type 2 (HSV-2) has the potential to limit the global burden of HSV-2 infection and disease, including genital ulcer disease and neonatal herpes, and is a global sexual and reproductive health priority. Another important potential benefit of an HSV-2 vaccine would be to decrease HIV infections, as HSV-2 increases the risk of HIV-1 acquisition several-fold. Acute and chronic HSV-2 infection creates ulcerations and draws dendritic cells and activated CD4+ T cells into genital mucosa. These cells are targets for HIV entry and replication. Prophylactic HSV-2 vaccines (to prevent infection) and therapeutic vaccines (to modify or treat existing infections) are currently under development. By preventing or modifying infection, an effective HSV-2 vaccine could limit HSV-associated genital mucosal inflammation and thus HIV risk. However, a vaccine might have competing effects on HIV risk depending on its mechanism of action and cell populations generated in the genital mucosa. In this article, we review biologic interactions between HSV-2 and HIV-1, consider HSV-2 vaccine development in the context of HIV risk, and discuss implications and research needs for future HSV vaccine development. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pneumonia Prevention during a Humanitarian Emergency: Cost-effectiveness of Haemophilus Influenzae Type B Conjugate Vaccine and Pneumococcal Conjugate Vaccine in Somalia.

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Gargano, Lisa M; Hajjeh, Rana; Cookson, Susan T

2015-08-01

Pneumonia is a leading cause of death among children less than five years old during humanitarian emergencies. Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae are the leading causes of bacterial pneumonia. Vaccines for both of these pathogens are available to prevent pneumonia. Problem This study describes an economic analysis from a publicly funded health care system perspective performed on a birth cohort in Somalia, a country that has experienced a protracted humanitarian emergency. An impact and cost-effectiveness analysis was performed comparing: no vaccine, Hib vaccine only, pneumococcal conjugate vaccine 10 (PCV10) only, and both together administered through supplemental immunization activities (SIAs). The main summary measure was the incremental cost per disability-adjusted life-years (DALYs) averted. One-way sensitivity analysis was conducted for uncertainty in parameter values. Each SIA would avert a substantial number of cases and deaths. Compared with no vaccine, the DALYs averted by two SIAs for two doses of Hib vaccine was US $202.93 (lower and upper limits: $121.80-$623.52), two doses of PCV10 was US $161.51 ($107.24-$227.21), and two doses of both vaccines was US $152.42 ($101.20-$214.42). Variables that influenced the cost-effectiveness for each strategy most substantially were vaccine effectiveness, case fatality rates (CFRs), and disease burden. The World Health Organization (WHO) defines a cost-effective intervention as costing one to three times the per capita gross domestic product (GDP; in 2011, for Somalia=US $112). Based on the presented model, Hib vaccine alone, PCV10 alone, or Hib vaccine and PCV10 given together in SIAs are cost-effective interventions in Somalia. The WHO/Strategic Advisory Group of Experts decision-making factors for vaccine deployment appear to have all been met: the disease burden is large, the vaccine-related risk is low, prevention in this setting is more feasible than treatment, the vaccine

Cost-effectiveness of dog rabies vaccination programs in East Africa

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Borse, Rebekah H.; Atkins, Charisma Y.; Gambhir, Manoj; Undurraga, Eduardo A.; Blanton, Jesse D.; Kahn, Emily B.; Dyer, Jessie L.; Rupprecht, Charles E.

2018-01-01

Background Dog rabies annually causes 24,000–70,000 deaths globally. We built a spreadsheet tool, RabiesEcon, to aid public health officials to estimate the cost-effectiveness of dog rabies vaccination programs in East Africa. Methods RabiesEcon uses a mathematical model of dog-dog and dog-human rabies transmission to estimate dog rabies cases averted, the cost per human rabies death averted and cost per year of life gained (YLG) due to dog vaccination programs (US 2015 dollars). We used an East African human population of 1 million (approximately 2/3 living in urban setting, 1/3 rural). We considered, using data from the literature, three vaccination options; no vaccination, annual vaccination of 50% of dogs and 20% of dogs vaccinated semi-annually. We assessed 2 transmission scenarios: low (1.2 dogs infected per infectious dog) and high (1.7 dogs infected). We also examined the impact of annually vaccinating 70% of all dogs (World Health Organization recommendation for dog rabies elimination). Results Without dog vaccination, over 10 years there would a total of be approximately 44,000–65,000 rabid dogs and 2,100–2,900 human deaths. Annually vaccinating 50% of dogs results in 10-year reductions of 97% and 75% in rabid dogs (low and high transmissions scenarios, respectively), approximately 2,000–1,600 human deaths averted, and an undiscounted cost-effectiveness of $451-$385 per life saved. Semi-annual vaccination of 20% of dogs results in in 10-year reductions of 94% and 78% in rabid dogs, and approximately 2,000–1,900 human deaths averted, and cost $404-$305 per life saved. In the low transmission scenario, vaccinating either 50% or 70% of dogs eliminated dog rabies. Results were most sensitive to dog birth rate and the initial rate of dog-to-dog transmission (Ro). Conclusions Dog rabies vaccination programs can control, and potentially eliminate, dog rabies. The frequency and coverage of vaccination programs, along with the level of dog rabies

Vaccination with melanoma lysate-pulsed dendritic cells, of patients with advanced colorectal carcinoma: report from a phase I study

DEFF Research Database (Denmark)

Burgdorf, S K; Fischer, A; Claesson, M H

2006-01-01

Immune therapy have shown new and exciting perspectives for cancer treatment. Aim of our study was to evaluate toxicity and possible adverse effects from vaccination of patients with advanced colorectal cancer with autologous dendritic cells (DC) pulsed with lysate from a newly developed melanoma...... contained 3-5 x 10(6) DCs. Five of the six patients received all five vaccines. The treatment was well tolerated in all patients without any observed vaccine-correlated adverse effects. Treatment with this DC-based cancer vaccine proved safe and non-toxic.......Immune therapy have shown new and exciting perspectives for cancer treatment. Aim of our study was to evaluate toxicity and possible adverse effects from vaccination of patients with advanced colorectal cancer with autologous dendritic cells (DC) pulsed with lysate from a newly developed melanoma...... and selected melanoma cell line enriched in expression of MAGE-A antigens and deficient in expression of melanoma differentiation antigens: tyrosinase, MART-1 and gp100. Vaccinations were administered intradermally on the proximal thigh with a total of five given vaccines at 2 weeks intervals. Each vaccine...

Cost-effectiveness analysis of prophylactic cervical cancer vaccination in Japanese women.

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Konno, Ryo; Sasagawa, Toshiyuki; Fukuda, Takashi; Van Kriekinge, Georges; Demarteau, Nadia

2010-04-01

The incidence of cervical cancer (CC) is high in Japan and is further increasing among women younger than 30 years. This burden could be reduced by the implementation of a CC vaccine, but its cost-effectiveness is unknown. We quantified the clinical impact and assessed the cost-effectiveness of adding CC vaccination at age 12 to the current screening in place in Japan with a lifetime Markov model adapted to the Japanese setting. Transition probabilities and utility values were obtained from public databases. Direct costs for treatment and screening were estimated using Japanese medical fees. Annual costs and benefits were discounted at 3%. Sensitivity analyses were conducted on the age at vaccination, the vaccine characteristics, the discount rates, the proportion of human papillomavirus types 16/18 in cancer, and the screening coverage. Vaccinating a 12-year-old cohort was predicted to reduce CC incidence and deaths from CC by 73%. These clinical effects were associated with an incremental cost-effectiveness ratio of yen1.8 million per quality-adjusted life year gained. The incremental cost-effectiveness ratio of vaccinating all 10- to 45-year-old women was yen2.8 million per quality-adjusted life year, still below the threshold value. The implementation of a CC vaccination in Japan could reduce the CC burden in a very cost-effective manner for women up to 45 years.

Modified Vaccinia Virus Ankara: History, Value in Basic Research, and Current Perspectives for Vaccine Development.

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Volz, A; Sutter, G

2017-01-01

Safety tested Modified Vaccinia virus Ankara (MVA) is licensed as third-generation vaccine against smallpox and serves as a potent vector system for development of new candidate vaccines against infectious diseases and cancer. Historically, MVA was developed by serial tissue culture passage in primary chicken cells of vaccinia virus strain Ankara, and clinically used to avoid the undesirable side effects of conventional smallpox vaccination. Adapted to growth in avian cells MVA lost the ability to replicate in mammalian hosts and lacks many of the genes orthopoxviruses use to conquer their host (cell) environment. As a biologically well-characterized mutant virus, MVA facilitates fundamental research to elucidate the functions of poxvirus host-interaction factors. As extremely safe viral vectors MVA vaccines have been found immunogenic and protective in various preclinical infection models. Multiple recombinant MVA currently undergo clinical testing for vaccination against human immunodeficiency viruses, Mycobacterium tuberculosis or Plasmodium falciparum. The versatility of the MVA vector vaccine platform is readily demonstrated by the swift development of experimental vaccines for immunization against emerging infections such as the Middle East Respiratory Syndrome. Recent advances include promising results from the clinical testing of recombinant MVA-producing antigens of highly pathogenic avian influenza virus H5N1 or Ebola virus. This review summarizes our current knowledge about MVA as a unique strain of vaccinia virus, and discusses the prospects of exploiting this virus as research tool in poxvirus biology or as safe viral vector vaccine to challenge existing and future bottlenecks in vaccinology. © 2017 Elsevier Inc. All rights reserved.

Development and evaluation of a replicon particle vaccine expressing the E2 glycoprotein of bovine viral diarrhea virus (BVDV in cattle

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Loy John Dustin

2013-01-01

Full Text Available Abstract Background Bovine viral diarrhea virus is one of the most significant and costly viral pathogens of cattle worldwide. Alphavirus-derived replicon particles have been shown to be safe and highly effective vaccine vectors against a variety of human and veterinary pathogens. Replicon particles are non-propagating, DIVA compatible, and can induce both humoral and cell mediated immune responses. This is the first experiment to demonstrate that Alphavirus-based replicon particles can be utilized in a standard prime/boost vaccination strategy in calves against a commercially significant bovine pathogen. Findings Replicon particles that express bovine viral diarrhea virus sub-genotype 1b E2 glycoprotein were generated and expression was confirmed in vitro using polyclonal and monoclonal antibodies specific to E2. Vaccine made from particles was generated in Vero cells and administered to BVDV free calves in a prime/boost regimen at two dosage levels. Vaccination resulted in neutralizing antibody titers that cross-neutralized both type 1 and type 2 BVD genotypes following booster vaccination. Additionally, high dose vaccine administration demonstrated some protection from clinical disease and significantly reduced the degree of leukopenia caused by viral infection. Conclusions Replicon particle vaccines administered in a prime/boost regimen expressing BVDV E2 glycoprotein can induce cross-neutralizing titers, reduce leukopenia post challenge, and mitigate clinical disease in calves. This strategy holds promise for a safe and effective vaccine to BVDV.

Adjuvants for vaccines to drugs of abuse and addiction.

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Alving, Carl R; Matyas, Gary R; Torres, Oscar; Jalah, Rashmi; Beck, Zoltan

2014-09-22

Immunotherapeutic vaccines to drugs of abuse, including nicotine, cocaine, heroin, oxycodone, methamphetamine, and others are being developed. The theoretical basis of such vaccines is to induce antibodies that sequester the drug in the blood in the form of antibody-bound drug that cannot cross the blood brain barrier, thereby preventing psychoactive effects. Because the drugs are haptens a successful vaccine relies on development of appropriate hapten-protein carrier conjugates. However, because induction of high and prolonged levels of antibodies is required for an effective vaccine, and because injection of T-independent haptenic drugs of abuse does not induce memory recall responses, the role of adjuvants during immunization plays a critical role. As reviewed herein, preclinical studies often use strong adjuvants such as complete and incomplete Freund's adjuvant and others that cannot be, or in the case of many newer adjuvants, have never been, employed in humans. Balanced against this, the only adjuvant that has been included in candidate vaccines in human clinical trials to nicotine and cocaine has been aluminum hydroxide gel. While aluminum salts have been widely utilized worldwide in numerous licensed vaccines, the experience with human responses to aluminum salt-adjuvanted vaccines to haptenic drugs of abuse has suggested that the immune responses are too weak to allow development of a successful vaccine. What is needed is an adjuvant or combination of adjuvants that are safe, potent, widely available, easily manufactured, and cost-effective. Based on our review of the field we recommend the following adjuvant combinations either for research or for product development for human use: aluminum salt with adsorbed monophosphoryl lipid A (MPLA); liposomes containing MPLA [L(MPLA)]; L(MPLA) adsorbed to aluminum salt; oil-in-water emulsion; or oil-in-water emulsion containing MPLA. Copyright © 2014. Published by Elsevier Ltd.

Priming-boosting vaccination with recombinant Mycobacterium bovis bacillus Calmette-Guérin and a nonreplicating vaccinia virus recombinant leads to long-lasting and effective immunity.

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Ami, Yasushi; Izumi, Yasuyuki; Matsuo, Kazuhiro; Someya, Kenji; Kanekiyo, Masaru; Horibata, Shigeo; Yoshino, Naoto; Sakai, Koji; Shinohara, Katsuaki; Matsumoto, Sohkichi; Yamada, Takeshi; Yamazaki, Shudo; Yamamoto, Naoki; Honda, Mitsuo

2005-10-01

Virus-specific T-cell responses can limit immunodeficiency virus type 1 (HIV-1) transmission and prevent disease progression and so could serve as the basis for an affordable, safe, and effective vaccine in humans. To assess their potential for a vaccine, we used Mycobacterium bovis bacillus Calmette-Guérin (BCG)-Tokyo and a replication-deficient vaccinia virus strain (DIs) as vectors to express full-length gag from simian immunodeficiency viruses (SIVs) (rBCG-SIVgag and rDIsSIVgag). Cynomolgus macaques were vaccinated with either rBCG-SIVgag dermally as a single modality or in combination with rDIsSIVgag intravenously. When cynomologus macaques were primed with rBCG-SIVgag and then boosted with rDIsSIVgag, high levels of gamma interferon (IFN-gamma) spot-forming cells specific for SIV Gag were induced. This combination regimen elicited effective protective immunity against mucosal challenge with pathogenic simian-human immunodeficiency virus for the 1 year the macaques were under observation. Antigen-specific intracellular IFN-gamma activity was similarly induced in each of the macaques with the priming-boosting regimen. Other groups receiving the opposite combination or the single-modality vaccines were not effectively protected. These results suggest that a recombinant M. bovis BCG-based vector may have potential as an HIV/AIDS vaccine when administered in combination with a replication-deficient vaccinia virus DIs vector in a priming-boosting strategy.

[EFFECTIVENESS OF PREVENTIVE VACCINE PROPHYLAXIS OF CHICKEN POX IN MILITARY COLLECTIVES].

Science.gov (United States)

Dubodelov, D V; Rybin, V V; Rikhter, V V; Yaroslavtsev, V V; Gritsik, A A; Kazanova, A S; Lavrov, V F; Semenenko, T A; Kuzin, S N

2015-01-01

Study the effectiveness of preventive vaccine prophylaxis of chicken pox in military collectives. In the focus of chicken pox, 200 servicemen of the new addition by conscription were immunized once against chicken pox; 97 servicemen by conscription of the new addition (comparison group) were not vaccinated. Epidemiologic and immunologic effectiveness of conduction of preventive vaccine prophylaxis in chicken pox focus were studied. In the group of 200 soldiers, that were present in the focus of infection and were immunized once against chicken pox, only 2 cases of this disease were registered (10 per thousand). In the comparison group, that consisted of 97 unvaccinated servicemen, chicken pox disease was registered in 7 individuals (72 per thousand). Epidemiologic effectiveness of preventive vaccine prophylaxis of chicken pox amounted to 86%. Immunologic effectiveness of vaccination 2-3 weeks after the immunization was 42%, and 2 months after--44%. Local reactions in the form of hyperemia (up to 1.5 cm) and edema were noted in 10% of the vaccinated at the location of preparation administration; in 1.7%--general reaction in the form of temperature increase to 37.8°C was observed. Post-vaccinal complications in the immunized group were not detected. Preventive vaccination of servicemen allows to minimize the spread of chicken pox, however can not serve as means of complete elimination of the infection from military collectives.

The yellow fever 17D vaccine virus as a vector for the expression of foreign proteins: development of new live flavivirus vaccines

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Myrna C Bonaldo

2000-01-01

Full Text Available The Flaviviridae is a family of about 70 mostly arthropod-borne viruses many of which are major public health problems with members being present in most continents. Among the most important are yellow fever (YF, dengue with its four serotypes and Japanese encephalitis virus. A live attenuated virus is used as a cost effective, safe and efficacious vaccine against YF but no other live flavivirus vaccines have been licensed. The rise of recombinant DNA technology and its application to study flavivirus genome structure and expression has opened new possibilities for flavivirus vaccine development. One new approach is the use of cDNAs encopassing the whole viral genome to generate infectious RNA after in vitro transcription. This methodology allows the genetic mapping of specific viral functions and the design of viral mutants with considerable potential as new live attenuated viruses. The use of infectious cDNA as a carrier for heterologous antigens is gaining importance as chimeric viruses are shown to be viable, immunogenic and less virulent as compared to the parental viruses. The use of DNA to overcome mutation rates intrinsic of RNA virus populations in conjunction with vaccine production in cell culture should improve the reliability and lower the cost for production of live attenuated vaccines. The YF virus despite a long period ignored by researchers probably due to the effectiveness of the vaccine has made a come back, both in nature as human populations grow and reach endemic areas as well as in the laboratory being a suitable model to understand the biology of flaviviruses in general and providing new alternatives for vaccine development through the use of the 17D vaccine strain.

Assessing effects of cholera vaccination in the presence of interference.

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Perez-Heydrich, Carolina; Hudgens, Michael G; Halloran, M Elizabeth; Clemens, John D; Ali, Mohammad; Emch, Michael E

2014-09-01

Interference occurs when the treatment of one person affects the outcome of another. For example, in infectious diseases, whether one individual is vaccinated may affect whether another individual becomes infected or develops disease. Quantifying such indirect (or spillover) effects of vaccination could have important public health or policy implications. In this article we use recently developed inverse-probability weighted (IPW) estimators of treatment effects in the presence of interference to analyze an individually-randomized, placebo-controlled trial of cholera vaccination that targeted 121,982 individuals in Matlab, Bangladesh. Because these IPW estimators have not been employed previously, a simulation study was also conducted to assess the empirical behavior of the estimators in settings similar to the cholera vaccine trial. Simulation study results demonstrate the IPW estimators can yield unbiased estimates of the direct, indirect, total, and overall effects of vaccination when there is interference provided the untestable no unmeasured confounders assumption holds and the group-level propensity score model is correctly specified. Application of the IPW estimators to the cholera vaccine trial indicates the presence of interference. For example, the IPW estimates suggest on average 5.29 fewer cases of cholera per 1000 person-years (95% confidence interval 2.61, 7.96) will occur among unvaccinated individuals within neighborhoods with 60% vaccine coverage compared to neighborhoods with 32% coverage. Our analysis also demonstrates how not accounting for interference can render misleading conclusions about the public health utility of vaccination. © 2014, The International Biometric Society.

Reducing AD-like pathology in 3xTg-AD mouse model by DNA epitope vaccine - a novel immunotherapeutic strategy.

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Nina Movsesyan

Full Text Available BACKGROUND: The development of a safe and effective AD vaccine requires a delicate balance between providing an adequate anti-Abeta antibody response sufficient to provide therapeutic benefit, while eliminating an adverse T cell-mediated proinflammatory autoimmune response. To achieve this goal we have designed a prototype chemokine-based DNA epitope vaccine expressing a fusion protein that consists of 3 copies of the self-B cell epitope of Abeta(42 (Abeta(1-11 , a non-self T helper cell epitope (PADRE, and macrophage-derived chemokine (MDC/CCL22 as a molecular adjuvant to promote a strong anti-inflammatory Th2 phenotype. METHODS AND FINDINGS: We generated pMDC-3Abeta(1-11-PADRE construct and immunized 3xTg-AD mouse model starting at age of 3-4 months old. We demonstrated that prophylactic immunizations with the DNA epitope vaccine generated a robust Th2 immune response that induced high titers of anti-Abeta antibody, which in turn inhibited accumulation of Abeta pathology in the brains of older mice. Importantly, vaccination reduced glial activation and prevented the development of behavioral deficits in aged animals without increasing the incidence of microhemorrhages. CONCLUSIONS: Data from this transitional pre-clinical study suggest that our DNA epitope vaccine could be used as a safe and effective strategy for AD therapy. Future safety and immunology studies in large animals with the goal to achieve effective humoral immunity without adverse effects should help to translate this study to human clinical trials.

Risk perception, risk management and safety assessment: what can governments do to increase public confidence in their vaccine system?

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MacDonald, Noni E; Smith, Jennifer; Appleton, Mary

2012-09-01

For decades vaccine program managers and governments have devoted many resources to addressing public vaccine concerns, vaccine risk perception, risk management and safety assessment. Despite ever growing evidence that vaccines are safe and effective, public concerns continue. Education and evidence based scientific messages have not ended concerns. How can governments and programs more effectively address the public's vaccine concerns and increase confidence in the vaccine safety system? Vaccination hesitation has been attributed to concerns about vaccine safety, perceptions of high vaccine risks and low disease risk and consequences. Even when the public believes vaccines are important for protection many still have concerns about vaccine safety. This overview explores how heuristics affect public perception of vaccines and vaccine safety, how the public finds and uses vaccine information, and then proposes strategies for changes in the approach to vaccine safety communications. Facts and evidence confirming the safety of vaccines are not enough. Vaccine beliefs and behaviours must be shaped. This will require a shift in the what, when, how and why of vaccine risk and benefit communication content and practice. A change to a behavioural change strategy such as the WHO COMBI program that has been applied to disease eradication efforts is suggested. Copyright © 2011. Published by Elsevier Ltd.. All rights reserved.

Meeting the challenge: prevention of pneumococcal disease with conjugate vaccines

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Echániz-Avilés Irma Gabriela

2001-01-01

Full Text Available Streptococcus pneumoniae is one of the leading causes of both invasive and noninvasive diseases in the pediatric population and continues to represent a significant public health burden worldwide. The increasing incidence of antibioticresistant strains of the pathogen has complicated treatment and management of the various pneumococcal disease manifestations. Thus, the best management strategy may be the prevention of pneumococcal diseases through vaccination. Although several pneumococcal conjugate vaccines have been clinically studied in infants and children, only a 7-valent conjugate vaccine (PNCRM7; Prevnar®/Prevenar® is currently approved for the prevention of invasive disease. Vaccination with PNCRM7 is safe and effective in infants and young children. Routine vaccination with the conjugate vaccine could improve outcomes by safeguarding against the development of antibiotic-resistant strains of S. pneumoniae, thus simplifying the management of pneumococcal disease. Additionally, the overall costs associated with the treatment of pneumococcal diseases could be substantially reduced, particularly in developing countries. The time has come for fully applying this new advancement against S. pneumoniae, to benefit the children of the world. The Spanish version of this paper is available at: http://www.insp.mx/salud/index.html

Effects of Message Framing on Influenza Vaccination: Understanding the Role of Risk Disclosure, Perceived Vaccine Efficacy, and Felt Ambivalence.

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Kim, Sungsu; Pjesivac, Ivanka; Jin, Yan

2017-10-20

The current study examined the effects of framing in promotional health messages on intention to vaccinate against seasonal influenza virus. The findings of an experimental study (N = 86) indicated that exposure to both benefits and side effects of vaccination (gain-framed with risk disclosure message) led to lower intention to receive the flu vaccine. This relationship was mediated by both perceived vaccine efficacy and felt ambivalence in a serial order, revealing the underlying psychological mechanisms important for understanding health-related behaviors. Theoretical implications of constructing sub-framed messages are discussed and the concept of second-order framing is introduced.

Rabies vaccines: where do we stand, where are we heading?

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Kaur, Manpreet; Garg, Rajni; Singh, Samer; Bhatnagar, Rakesh

2015-03-01

Rabies being the most lethal zoonotic, vaccine-preventable viral disease with worldwide distribution of reservoir wild animals presents unique challenges for its diagnosis, management and control. Although vaccines available are highly effective, which had played the key role in controlling rabies in North America, western Europe and in a number of Asian and Latin American countries, the requirement of multiple doses along with boosters, associated cost to reduce the incidence in wild animals and prophylactic human vaccination has remained a major impediment towards achieving the same goals in poorer parts of the world such as sub-Saharan Africa and southeast Asia. Current efforts to contain rabies worldwide are directed towards the development of more safe, cheaper and efficacious vaccines along with anti-rabies antibodies for post-exposure prophylaxis. The work presented here provides an overview of the advances made towards controlling the human rabies, particularly in last 10 years, and future perspective.

Effectiveness of influenza vaccine against laboratory-confirmed influenza, in the late 2011–2012 season in Spain, among population targeted for vaccination

Science.gov (United States)

2013-01-01

Background In Spain, the influenza vaccine effectiveness (VE) was estimated in the last three seasons using the observational study cycEVA conducted in the frame of the existing Spanish Influenza Sentinel Surveillance System. The objective of the study was to estimate influenza vaccine effectiveness (VE) against medically attended, laboratory-confirmed influenza-like illness (ILI) among the target groups for vaccination in Spain in the 2011–2012 season. We also studied influenza VE in the early (weeks 52/2011-7/2012) and late (weeks 8-14/2012) phases of the epidemic and according to time since vaccination. Methods Medically attended patients with ILI were systematically swabbed to collect information on exposure, laboratory outcome and confounding factors. Patients belonging to target groups for vaccination and who were swabbed 4 months, respectively, since vaccination. A decrease in VE with time since vaccination was only observed in individuals aged ≥ 65 years. Regarding the phase of the season, decreasing point estimates were only observed in the early phase, whereas very low or null estimates were obtained in the late phase for the shortest time interval. Conclusions The 2011–2012 influenza vaccine showed a low-to-moderate protective effect against medically attended, laboratory-confirmed influenza in the target groups for vaccination, in a late season and with a limited match between the vaccine and circulating strains. The suggested decrease in influenza VE with time since vaccination was mostly observed in the elderly population. The decreasing protective effect of the vaccine in the late part of the season could be related to waning vaccine protection because no viral changes were identified throughout the season. PMID:24053661

[Introduction of vaccination against human papillomavirus in developing countries: update and perspectives].

Science.gov (United States)

Hessel, L

2009-08-01

Cervical cancer and other diseases related to human papillomavirus (HPV) represent a global public health problem. Safe and effective vaccines are now available and already used in many industrialized countries. Immunization offers the best hope for protecting the population against a disease that is the second most deadly cancer in the developing world and the first most deadly in Africa. The World Health Organization currently recommends introduction of HVP vaccination in developing countries. Widespread vaccination could be beneficial in numerous domains other than primary prevention of cervical cancer. Efforts to overcome the numerous obstacles and speed up implementation of HVP vaccination programs are now underway in many areas ranging from related scientific issues such as epidemiology and clinical research to administrative concerns such as healthcare economics, vaccination guidelines, public acceptation, program funding, and universal access. Vaccine manufacturers have committed themselves to working in partnership with national and international organizations to ensure access to HPV vaccine for all countries regardless of economic level, Although numerous issues must be resolved to optimize the use of HPV vaccines and ensure synergistic integration of vaccination, screening and treatment, current initiatives and efforts should allow introduction of HPV vaccination in developing countries in a not too distant future.

Cost-effectiveness of rotavirus vaccination in Kenya and Uganda.

Science.gov (United States)

Sigei, Charles; Odaga, John; Mvundura, Mercy; Madrid, Yvette; Clark, Andrew David

2015-05-07

Rotavirus vaccines have the potential to prevent a substantial amount of life-threatening gastroenteritis in young African children. This paper presents the results of prospective cost-effectiveness analyses for rotavirus vaccine introduction for Kenya and Uganda. In each country, a national consultant worked with a national technical working group to identify appropriate data and validate study results. Secondary data on demographics, disease burden, health utilization, and costs were used to populate the TRIVAC cost-effectiveness model. The baseline analysis assumed an initial vaccine price of $0.20 per dose, corresponding to Gavi, the Vaccine Alliance stipulated copay for low-income countries. The incremental cost-effectiveness of a 2-dose rotavirus vaccination schedule was evaluated for 20 successive birth cohorts from the government perspective in both countries, and from the societal perspective in Uganda. Between 2014 and 2033, rotavirus vaccination can avert approximately 60,935 and 216,454 undiscounted deaths and hospital admissions respectively in children under 5 years in Kenya. In Uganda, the respective number of undiscounted deaths and hospital admission averted is 70,236 and 329,779 between 2016 and 2035. Over the 20-year period, the discounted vaccine program costs are around US$ 80 million in Kenya and US$ 60 million in Uganda. Discounted government health service costs avoided are US$ 30 million in Kenya and US$ 10 million in Uganda (or US$ 18 million including household costs). The cost per disability-adjusted life-year (DALY) averted from a government perspective is US$ 38 in Kenya and US$ 34 in Uganda (US$ 29 from a societal perspective). Rotavirus vaccine introduction is highly cost-effective in both countries in a range of plausible 'what-if' scenarios. The involvement of national experts improves the quality of data used, is likely to increase acceptability of the results in decision-making, and can contribute to strengthened national

Effectiveness of pneumococcal vaccination for elderly people in Catalonia, Spain: a case-control study.

Science.gov (United States)

Dominguez, Angela; Salleras, Lluis; Fedson, David S; Izquierdo, Conchita; Ruiz, Laura; Ciruela, Pilar; Fenoll, Asuncion; Casal, Julio

2005-05-01

Observational studies offer an approach to evaluating the effectiveness of vaccination programs. We evaluated the effectiveness of a 23-valent pneumococcal vaccination program for elderly people in Catalonia, Spain, in a matched-set case-control study. We identified 149 cases of invasive pneumococcal disease among patients aged > or =65 years who were hospitalized in 12 large hospitals in Catalonia during the period of 1 January 2001 through 31 March 2002. We selected 2 hospital control patients and 1 outpatient control subject for each case patient, matching on the basis of age and underlying medical conditions. We obtained their pneumococcal vaccination histories and used conditional logistic regression to determine effectiveness of vaccination. Among all 149 cases of invasive pneumococcal disease, 131 (87.9%) were caused by vaccine or vaccine-related serotypes. In the adjusted analysis, overall effectiveness of vaccination against infections due to all serotypes was 70% (95% confidence interval [CI], 48%-82%). Among immunocompetent subjects with or without high-risk conditions, effectiveness of vaccination was 76% (95% CI, 51%-88%), but among immunocompromised subjects it was 50% (95% CI, -44% to 82%). Among subjects with infections due to vaccine or vaccine-related serotypes, effectiveness of vaccination was 72% (95% CI, 50%-85%) overall and 78% (95% CI, 50%-90%) in those who were immunocompetent, but it was only 46% (95% CI, -54% to 81%) in those who were immunocompromised. Overall effectiveness of vaccination was 65% (95% CI, 35%-81%) during the noninfluenza period. Pneumococcal vaccination was effective in preventing invasive pneumococcal disease among all elderly persons in Catalonia. Effectiveness was greater in immunocompetent persons, most of whom had underlying high-risk conditions. The number of subjects was too small to determine whether vaccination was effective in those who were immunocompromised.

Too Late to Vaccinate? The Incremental Benefits and Cost-effectiveness of a Delayed Catch-up Program Using the 4-Valent Human Papillomavirus Vaccine in Norway

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Burger, Emily A.; Sy, Stephen; Nygård, Mari; Kristiansen, Ivar S.; Kim, Jane J.

2015-01-01

Background Human papillomavirus (HPV) vaccines are ideally administered before HPV exposure; therefore, catch-up programs for girls past adolescence have not been readily funded. We evaluated the benefits and cost-effectiveness of a delayed, 1-year female catch-up vaccination program in Norway. Methods We calibrated a dynamic HPV transmission model to Norwegian data and projected the costs and benefits associated with 8 HPV-related conditions while varying the upper vaccination age limit to 20, 22, 24, or 26 years. We explored the impact of vaccine protection in women with prior vaccine-targeted HPV infections, vaccine cost, coverage, and natural- and vaccine-induced immunity. Results The incremental benefits and cost-effectiveness decreased as the upper age limit for catch-up increased. Assuming a vaccine cost of $150/dose, vaccination up to age 20 years remained below Norway's willingness-to-pay threshold (approximately $83 000/quality-adjusted life year gained); extension to age 22 years was cost-effective at a lower cost per dose ($50–$75). At high levels of vaccine protection in women with prior HPV exposure, vaccinating up to age 26 years was cost-effective. Results were stable with lower coverage. Conclusions HPV vaccination catch-up programs, 5 years after routine implementation, may be warranted; however, even at low vaccine cost per dose, the cost-effectiveness of vaccinating beyond age 22 years remains uncertain. PMID:25057044

Directed antigen delivery as a vaccine strategy for an intracellular bacterial pathogen

Science.gov (United States)

Bouwer, H. G. Archie; Alberti-Segui, Christine; Montfort, Megan J.; Berkowitz, Nathan D.; Higgins, Darren E.

2006-03-01

We have developed a vaccine strategy for generating an attenuated strain of an intracellular bacterial pathogen that, after uptake by professional antigen-presenting cells, does not replicate intracellularly and is readily killed. However, after degradation of the vaccine strain within the phagolysosome, target antigens are released into the cytosol for endogenous processing and presentation for stimulation of CD8+ effector T cells. Applying this strategy to the model intracellular pathogen Listeria monocytogenes, we show that an intracellular replication-deficient vaccine strain is cleared rapidly in normal and immunocompromised animals, yet antigen-specific CD8+ effector T cells are stimulated after immunization. Furthermore, animals immunized with the intracellular replication-deficient vaccine strain are resistant to lethal challenge with a virulent WT strain of L. monocytogenes. These studies suggest a general strategy for developing safe and effective, attenuated intracellular replication-deficient vaccine strains for stimulation of protective immune responses against intracellular bacterial pathogens. CD8+ T cell | replication-deficient | Listeria monocytogenes

Rotavirus vaccine effectiveness in low-income settings: An evaluation of the test-negative design.

Science.gov (United States)

Schwartz, Lauren M; Halloran, M Elizabeth; Rowhani-Rahbar, Ali; Neuzil, Kathleen M; Victor, John C

2017-01-03

The test-negative design (TND), an epidemiologic method currently used to measure rotavirus vaccine (RV) effectiveness, compares the vaccination status of rotavirus-positive cases and rotavirus-negative controls meeting a pre-defined case definition for acute gastroenteritis. Despite the use of this study design in low-income settings, the TND has not been evaluated to measure rotavirus vaccine effectiveness. This study builds upon prior methods to evaluate the use of the TND for influenza vaccine using a randomized controlled clinical trial database. Test-negative vaccine effectiveness (VE-TND) estimates were derived from three large randomized placebo-controlled trials (RCTs) of monovalent (RV1) and pentavalent (RV5) rotavirus vaccines in sub-Saharan Africa and Asia. Derived VE-TND estimates were compared to the original RCT vaccine efficacy estimates (VE-RCTs). The core assumption of the TND (i.e., rotavirus vaccine has no effect on rotavirus-negative diarrhea) was also assessed. TND vaccine effectiveness estimates were nearly equivalent to original RCT vaccine efficacy estimates. Neither RV had a substantial effect on rotavirus-negative diarrhea. This study supports the TND as an appropriate epidemiologic study design to measure rotavirus vaccine effectiveness in low-income settings. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Gamma radiation effects on the cuban antimeningococcic BC vaccine

International Nuclear Information System (INIS)

Padron Soler, E.; Romay Penabad, Z.; Le Riveran Morales, E.; Campa Huergo, C.; Sierra Gonzalez, G.; Alfalla Valdes, L.; Prieto Miranda, E.

1994-01-01

The effects of gamma rays on the Cuban antimeningococcic BC vaccine properties were studied. These were performanced by simulation with different bio burden of microbial pollutants. The isolated spores of the pollutants of non- aseptic areas were used. Its D10 was determined as 2.045 Gy. On that basis, the sterilization dose setting was performed. The quality of the irradiated vaccine was performed according to the Cuban standards: sterility, protein and polysaccharide concentration, immunogenicity, per cent of protein adsorption, nonspecific innocuousness. There were observed non negative effects on the vaccine of the radiation process in the dose range of 0-25 Gy. It was also studied the preservation of the properties of the irradiated vaccine, by storing it during one year at four celsius grade. The results were satisfactory

An Ethical Justification for Expanding the Notion of Effectiveness in Vaccine Post-Market Monitoring: Insights from the HPV Vaccine in Canada.

Science.gov (United States)

Komparic, Ana; Smith, Maxwell J; Thompson, Alison

2016-04-01

Health regulators must carefully monitor the real-world safety and effectiveness of marketed vaccines through post-market monitoring in order to protect the public's health and promote those vaccines that best achieve public health goals. Yet, despite the fact that vaccines used in collective immunization programmes should be assessed in the context of a public health response, post-market effectiveness monitoring is often limited to assessing immunogenicity or limited programmatic features, rather than assessing effectiveness across populations. We argue that post-market monitoring ought to be expanded in two ways to reflect a 'public health notion of post-market effectiveness', which incorporates normative public health considerations: (i) effectiveness monitoring should yield higher quality data and grant special attention to underrepresented and vulnerable populations; and (ii) the scope of effectiveness should be expanded to include a consideration of the various social factors that maximize (and minimize) a vaccine's effectiveness at the population level, paying particular attention to how immunization programmes impact related health gradients. We use the case of the human papillomavirus vaccine in Canada to elucidate how expanding post-market effectiveness monitoring is necessary to close the gap between clinical practice and public health, and to ensure that vaccines are effective in a morally relevant sense.

Effect of early measles vaccine on pneumococcal colonization

DEFF Research Database (Denmark)

Hansen, Nadja Skadkær; Byberg, Stine; Hervig Jacobsen, Lars

2017-01-01

BACKGROUND: Measles vaccine (MV) may have non-specific beneficial effects for child health and particularly seems to prevent respiratory infections. Streptococcus pneumoniae is the leading cause of bacterial pneumonia among children worldwide, and nasopharyngeal colonization precedes infection....... OBJECTIVE: We investigated whether providing early MV at 18 weeks of age reduced pneumococcal colonization and/or density up to 9 months of age. METHOD: The study was conducted in 2013-2014 in Guinea-Bissau. Pneumococcal vaccine was not part of the vaccination program. Infants aged 18 weeks were block...

Comparison of the immunogenic effect of rabies vaccines

Energy Technology Data Exchange (ETDEWEB)

Kiss, Zs [Allatgyogyaszati Oltoanyagellenoerzoe Intezet, Budapest (Hungary)

1981-10-01

Immunogenic effect of the Lyssa and Lyssavac rabies vaccines were compared in sheep. Blood samples were collected 8 times from the experimental groups of 5 animals each during a 6-month period after vaccination. The dynamics of virus neutralizing antibodies was followed and the in vitro reactions of peripheral lymphocytes were studied. In the 3rd week after vaccination the titre of virus neutralizing antibodies was higher (1:128.4) in the experimental group immunized with the Lyssavac than in that immunized with the Lyssa vaccine (1:118) and it remained also at a higher level in the 6th month after vaccination (1:50) than that of the group immunized with the latter vaccine (1:20.4). As regards the in vitro reactions of lymphocytes, no essential differences were found either in the rates of immune rosette formation or in the degree of blastogenesis measured by the incorporation of /sup 3/HTdR. The mean values of IgG and IgM positive cells were also similar in both experimental groups as it was determined by immunofluorescence.

Safety evaluation in mice of the childhood immunization vaccines from two south-eastern states of Nigeria

Directory of Open Access Journals (Sweden)

Oli Angus Nnamdi

2015-02-01

Conclusions:: The vaccine samples tested were safe and did not affect the hematopoietic system adversely. The storage conditions of the vaccines in the States’ cold-chain stores had not compromised the safety of the vaccines.

RESPONSE OF VOLTA CHILDREN TO JET INOCULATION OF COMBINED LIVE MEASLES, SMALLPOX AND YELLOW FEVER VACCINES.

Science.gov (United States)

MEYER, H M; HOSTETLER, D D; BERNHEIN, B C; ROGERS, N G; LAMBIN, P; CHASSARY, A; LABUSQUIERE, R; SMADEL, J E

1964-01-01

An earlier study established that Upper Volta children respond to vaccination with the Enders live attenuated measles strain in the same general fashion as do children in the USA. The present report describes a second pilot project carried out in Ouagadougou, Upper Volta. During this investigation various mixtures of live measles, smallpox and 17D yellow fever vaccines were introduced into susceptible infants by jet injection. Combining the attenuated virus vaccines did not alter or accentuate the characteristic clinical reactions elicited by the individual components, nor was there evidence of significant immunological interference. From this experience it is concluded that combined vaccination with these agents may be safely and effectively employed in larger programmes as the need dictates.

Vaccination Games with Peer Effects in a Heterogeneous Hospital Worker Population

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Troy Tassier

2015-01-01

Full Text Available We develop a game theoretic model to analyze the Nash equilibrium of vaccine decisions in a hospital population with heterogeneous contacts. We use the model in conjunction with person-to-person contact data within a large university hospital. We simulate, using agent-based models, the probability of infection for various worker types in the data and use these probabilities to identify the Nash equilibrium vaccine choices of hospital workers. The analysis suggests that there may be large differences in vaccination rates among hospital worker groups. We extend the model to include peer effects within the game. The peer effects may create additional equilibria or may further cement existing equilibria depending on parameter values. Further, depending on the magnitude of the peer effects and the costs of infection and vaccination, peer effects may increase or decrease differences in worker group vaccination rates within the hospital.

Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for influenza vaccination in children

Science.gov (United States)

2010-01-01

Background Influenza vaccination in infants and children with existing health complications is current practice in many countries, but healthy children are also susceptible to influenza, sometimes with complications. The under-recognised burden of disease in young children is greater than in elderly populations and the number of paediatric influenza cases reported does not reflect the actual frequency of influenza. Discussion Vaccination of healthy children is not widespread in Europe despite clear demonstration of the benefits of vaccination in reducing the large health and economic burden of influenza. Universal vaccination of infants and children also provides indirect protection in other high-risk groups in the community. This paper contains the Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for the vaccination of infants and children against influenza. The aim of CEVAG is to encourage the efficient and safe use of vaccines to prevent and control infectious diseases. Summary CEVAG recommends the introduction of universal influenza vaccination for all children from the age of 6 months. Special attention is needed for children up to 60 months of age as they are at greatest risk. Individual countries should decide on how best to implement this recommendation based on their circumstances. PMID:20546586

Cost-effectiveness of canine vaccination to prevent human rabies in rural Tanzania.

Science.gov (United States)

Fitzpatrick, Meagan C; Hampson, Katie; Cleaveland, Sarah; Mzimbiri, Imam; Lankester, Felix; Lembo, Tiziana; Meyers, Lauren A; Paltiel, A David; Galvani, Alison P

2014-01-21

The annual mortality rate of human rabies in rural Africa is 3.6 deaths per 100 000 persons. Rabies can be prevented with prompt postexposure prophylaxis, but this is costly and often inaccessible in rural Africa. Because 99% of human exposures occur through rabid dogs, canine vaccination also prevents transmission of rabies to humans. To evaluate the cost-effectiveness of rabies control through annual canine vaccination campaigns in rural sub-Saharan Africa. We model transmission dynamics in dogs and wildlife and assess empirical uncertainty in the biological variables to make probability-based evaluations of cost-effectiveness. Epidemiologic variables from a contact-tracing study and literature and cost data from ongoing vaccination campaigns. Two districts of rural Tanzania: Ngorongoro and Serengeti. 10 years. Health policymaker. Vaccination coverage ranging from 0% to 95% in increments of 5%. Life-years for health outcomes and 2010 U.S. dollars for economic outcomes. Annual canine vaccination campaigns were very cost-effective in both districts compared with no canine vaccination. In Serengeti, annual campaigns with as much as 70% coverage were cost-saving. Across a wide range of variable assumptions and levels of societal willingness to pay for life-years, the optimal vaccination coverage for Serengeti was 70%. In Ngorongoro, although optimal coverage depended on willingness to pay, vaccination campaigns were always cost-effective and lifesaving and therefore preferred. Canine vaccination was very cost-effective in both districts, but there was greater uncertainty about the optimal coverage in Ngorongoro. Annual canine rabies vaccination campaigns conferred extraordinary value and dramatically reduced the health burden of rabies. National Institutes of Health.

Reverse Genetics Approaches for the Development of Influenza Vaccines

Science.gov (United States)

Nogales, Aitor; Martínez-Sobrido, Luis

2016-01-01

Influenza viruses cause annual seasonal epidemics and occasional pandemics of human respiratory disease. Influenza virus infections represent a serious public health and economic problem, which are most effectively prevented through vaccination. However, influenza viruses undergo continual antigenic variation, which requires either the annual reformulation of seasonal influenza vaccines or the rapid generation of vaccines against potential pandemic virus strains. The segmented nature of influenza virus allows for the reassortment between two or more viruses within a co-infected cell, and this characteristic has also been harnessed in the laboratory to generate reassortant viruses for their use as either inactivated or live-attenuated influenza vaccines. With the implementation of plasmid-based reverse genetics techniques, it is now possible to engineer recombinant influenza viruses entirely from full-length complementary DNA copies of the viral genome by transfection of susceptible cells. These reverse genetics systems have provided investigators with novel and powerful approaches to answer important questions about the biology of influenza viruses, including the function of viral proteins, their interaction with cellular host factors and the mechanisms of influenza virus transmission and pathogenesis. In addition, reverse genetics techniques have allowed the generation of recombinant influenza viruses, providing a powerful technology to develop both inactivated and live-attenuated influenza vaccines. In this review, we will summarize the current knowledge of state-of-the-art, plasmid-based, influenza reverse genetics approaches and their implementation to provide rapid, convenient, safe and more effective influenza inactivated or live-attenuated vaccines. PMID:28025504

EXPERIMENTAL LIPOSOMAL VIRAL VACCINE SAFETY

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Romanova OA

2016-12-01

Full Text Available Introduction. With the transport links development there is rather important issue respiratory viral infections spread, especially influenza. The only method controlling influenza is vaccination. Search and development effective and safe vaccines is important. Material and methods. In base SO "Mechnikov Institute Microbiology and Immunology National Ukrainian Academy Medical Sciences" in the scientific theme "Developing new approaches to creating viral vaccines and study specific activity depending of type and degree component`s modification" was created several experimental influenza vaccine with subsequent component`s modification for selecting the most optimal pattern of safety and immunogenicity. In assessing the influenza vaccine safety is using a few criteria, including, reactivity, as measured by the frequency of local and systemic adverse (negative effects, which due to its introduction, and for lipid content drugs, ability to influence oxidation processes. At present study phase was determined: a systemic reaction and local reaction of delayed-type hypersensitivity (foot pad swelling assay;b lipids and proteins peroxidation processes after administration officinal and experimental vaccines (content protein’s carbonyl groups, lipid’s hydroperoxides, activity of glutathione-peroxidase.Study objects were trivalent seasonal influenza vaccine, "Vaxigrip" (Sanofi Pasteur, S.A., France, "Inflexal V" (Biotech Ltd. Berne, Switzerland and experimental vaccine samples. Highest immunogenicity vaccines had undergone improvements and modifications using adjuvant systems and acylation influenza proteins. Liposomes 2 – the experimental influenza vaccine with a liposome negative charge and antigenic composition like split vaccines "Vaksihryp". Liposomes 2.1 - the adjuvantexperimental influenza vaccine with modifications liposomal components (etoniy and chlorophyllipt molecules embedded in liposomal membrane. Liposomes 2.2 - the adjuvant

Seasonal influenza vaccination for children in Thailand: a cost-effectiveness analysis.

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Meeyai, Aronrag; Praditsitthikorn, Naiyana; Kotirum, Surachai; Kulpeng, Wantanee; Putthasri, Weerasak; Cooper, Ben S; Teerawattananon, Yot

2015-05-01

Seasonal influenza is a major cause of mortality worldwide. Routine immunization of children has the potential to reduce this mortality through both direct and indirect protection, but has not been adopted by any low- or middle-income countries. We developed a framework to evaluate the cost-effectiveness of influenza vaccination policies in developing countries and used it to consider annual vaccination of school- and preschool-aged children with either trivalent inactivated influenza vaccine (TIV) or trivalent live-attenuated influenza vaccine (LAIV) in Thailand. We also compared these approaches with a policy of expanding TIV coverage in the elderly. We developed an age-structured model to evaluate the cost-effectiveness of eight vaccination policies parameterized using country-level data from Thailand. For policies using LAIV, we considered five different age groups of children to vaccinate. We adopted a Bayesian evidence-synthesis framework, expressing uncertainty in parameters through probability distributions derived by fitting the model to prospectively collected laboratory-confirmed influenza data from 2005-2009, by meta-analysis of clinical trial data, and by using prior probability distributions derived from literature review and elicitation of expert opinion. We performed sensitivity analyses using alternative assumptions about prior immunity, contact patterns between age groups, the proportion of infections that are symptomatic, cost per unit vaccine, and vaccine effectiveness. Vaccination of children with LAIV was found to be highly cost-effective, with incremental cost-effectiveness ratios between about 2,000 and 5,000 international dollars per disability-adjusted life year averted, and was consistently preferred to TIV-based policies. These findings were robust to extensive sensitivity analyses. The optimal age group to vaccinate with LAIV, however, was sensitive both to the willingness to pay for health benefits and to assumptions about contact

Effective chikungunya virus-like particle vaccine produced in insect cells.

Directory of Open Access Journals (Sweden)

Stefan W Metz

Full Text Available The emerging arthritogenic, mosquito-borne chikungunya virus (CHIKV causes severe disease in humans and represents a serious public health threat in countries where Aedes spp mosquitoes are present. This study describes for the first time the successful production of CHIKV virus-like particles (VLPs in insect cells using recombinant baculoviruses. This well-established expression system is rapidly scalable to volumes required for epidemic responses and proved well suited for processing of CHIKV glycoproteins and production of enveloped VLPs. Herein we show that a single immunization with 1 µg of non-adjuvanted CHIKV VLPs induced high titer neutralizing antibody responses and provided complete protection against viraemia and joint inflammation upon challenge with the Réunion Island CHIKV strain in an adult wild-type mouse model of CHIKV disease. CHIKV VLPs produced in insect cells using recombinant baculoviruses thus represents as a new, safe, non-replicating and effective vaccine candidate against CHIKV infections.

Vaccines for tick-borne diseases and cost-effectiveness of vaccination : a public health challenge to reduce the diseases’ burden

NARCIS (Netherlands)

Smit, Renata; Postma, Maarten J

Tick-borne encephalitis (TBE) and Lyme borreliosis (LB) are tick-borne diseases (TBDs), and both present an increasing burden worldwide. Vaccination as public health intervention could be the most effective way to reduce this burden. TBE vaccines are available, but vaccines against LB are still in

The Case for Adolescent HIV Vaccination in South Africa: A Cost-Effectiveness Analysis.

Science.gov (United States)

Moodley, Nishila; Gray, Glenda; Bertram, Melanie

2016-01-01

Despite comprising 0.7% of the world population, South Africa is home to 18% of the global human immunodeficiency virus (HIV) prevalence. Unyielding HIV subepidemics among adolescents threaten national attempts to curtail the disease burden. Should an HIV vaccine become available, establishing its point of entry into the health system becomes a priority. This study assesses the impact of school-based HIV vaccination and explores how variations in vaccine characteristics affect cost-effectiveness. The cost per quality adjusted life year (QALY) gained associated with school-based adolescent HIV vaccination services was assessed using Markov modeling that simulated annual cycles based on national costing data. The estimation was based on a life expectancy of 70 years and employs the health care provider perspective. The simultaneous implementation of HIV vaccination services with current HIV management programs would be cost-effective, even at relatively higher vaccine cost. At base vaccine cost of US$ 12, the incremental cost effectiveness ratio (ICER) was US$ 43 per QALY gained, with improved ICER values yielded at lower vaccine costs. The ICER was sensitive to duration of vaccine mediated protection and variations in vaccine efficacy. Data from this work demonstrate that vaccines offering longer duration of protection and at lower cost would result in improved ICER values. School-based HIV vaccine services of adolescents, in addition to current HIV prevention and treatment health services delivered, would be cost-effective.

Modelling effectiveness of herd level vaccination against Q fever in dairy cattle

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Courcoul Aurélie

2011-05-01

Full Text Available Abstract Q fever is a worldwide zoonosis caused by the bacterium Coxiella burnetii. The control of this infection in cattle is crucial: infected ruminants can indeed encounter reproductive disorders and represent the most important source of human infection. In the field, vaccination is currently advised in infected herds but the comparative effectiveness of different vaccination protocols has never been explored: the duration of the vaccination programme and the category of animals to be vaccinated have to be determined. Our objective was to compare, by simulation, the effectiveness over 10 years of three different vaccination strategies in a recently infected dairy cattle herd. A stochastic individual-based epidemic model coupled with a model of herd demography was developed to simulate three temporal outputs (shedder prevalence, environmental bacterial load and number of abortions and to calculate the extinction rate of the infection. For all strategies, the temporal outputs were predicted to strongly decrease with time at least in the first years of vaccination. However, vaccinating only three years was predicted inadequate to stabilize these dynamic outputs at a low level. Vaccination of both cows and heifers was predicted as being slightly more effective than vaccinating heifers only. Although the simulated extinction rate of the infection was high for both scenarios, the outputs decreased slower when only heifers were vaccinated. Our findings shed new light on vaccination effectiveness related to Q fever. Moreover, the model can be further modified for simulating and assessing various Q fever control strategies such as environmental and hygienic measures.

Development, Production, and Postmarketing Surveillance of Hepatitis A Vaccines in China

Science.gov (United States)

Cui, Fuqiang; Liang, Xiaofeng; Wang, Fuzhen; Zheng, Hui; Hutin, Yvan J; Yang, Weizhong

2014-01-01

China has long experience using live attenuated and inactivated vaccines against hepatitis A virus (HAV) infection. We summarize this experience and provide recent data on adverse events after immunization (AEFIs) with hepatitis A vaccines in China. We reviewed the published literature (in Chinese and English) and the published Chinese regulatory documents on hepatitis A vaccine development, production, and postmarketing surveillance of AEFI. We described the safety, immunogenicity, and efficacy of hepatitis A vaccines and horizontal transmission of live HAV vaccine in China. In clinical trials, live HAV vaccine was associated with fever (0.4%–5% of vaccinees), rash (0%–1.1%), and elevated alanine aminotransferase (0.015%). Inactivated HAV vaccine was associated with fever (1%–8%), but no serious AEFIs were reported. Live HAV vaccine had seroconversion rates of 83% to 91%, while inactivated HAV vaccine had seroconversion rates of 95% to 100%. Community trials showed efficacy rates of 90% to 95% for live HAV and 95% to 100% for inactivated HAV vaccine. Postmarketing surveillance showed that HAV vaccination resulted in an AEFI incidence rate of 34 per million vaccinees, which accounted for 0.7% of adverse events reported to the China AEFI monitoring system. There was no difference in AEFI rates between live and inactivated HAV vaccines. Live and inactivated HAV vaccines manufactured in China were immunogenic, effective, and safe. Live HAV vaccine had substantial horizontal transmission due to vaccine virus shedding; thus, further monitoring of the safety of virus shedding is warranted. PMID:24681843

A small jab - a big effect: nonspecific immunomodulation by vaccines.

Science.gov (United States)

Benn, Christine S; Netea, Mihai G; Selin, Liisa K; Aaby, Peter

2013-09-01

Recent epidemiological studies have shown that, in addition to disease-specific effects, vaccines against infectious diseases have nonspecific effects on the ability of the immune system to handle other pathogens. For instance, in randomized trials tuberculosis and measles vaccines are associated with a substantial reduction in overall child mortality, which cannot be explained by prevention of the target disease. New research suggests that the nonspecific effects of vaccines are related to cross-reactivity of the adaptive immune system with unrelated pathogens, and to training of the innate immune system through epigenetic reprogramming. Hence, epidemiological findings are backed by immunological data. This generates a new understanding of the immune system and about how it can be modulated by vaccines to impact the general resistance to disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Consensus position document on the child with an allergic reaction after vaccination or an allergy to vaccine components].

Science.gov (United States)

Echeverría Zudaire, L; Ortigosa Del Castillo, L; Alonso Lebrero, E; Álvarez García, F J; Cortés Álvarez, N; García Sánchez, N; Martorell Aragonés, A

2015-07-01

Vaccinations are one of the main public health tools for the control of vaccine-preventable diseases. If a child is labeled to have had an allergic reaction to a vaccine, the next immunizations will probably be suspended in that child, with the risks involved in this decision. The rate of severe allergic reactions is very low, ranging between 0.5-1/100,000 doses. The causes of allergic reactions to vaccines, more than the vaccine itself, are often due to residual protein components in the manufacturing process, such as gelatin or egg, and rarely to yeast or latex. Most of vaccine reactions are mild, localized at the site of injection, but in some circumstances, severe anaphylactic reactions can occur. If an immediate-type allergic reaction is suspected when vaccinating, or a child allergic to some of the vaccine components has to be vaccinated, a correct diagnosis of the possible allergy has to be made. The usual components of each vaccine should be known, in order to determine if vaccination can be performed safely on the child. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

Increased immunogenicity of the MF59-adjuvanted influenza vaccine compared to a conventional subunit vaccine in elderly subjects

International Nuclear Information System (INIS)

Gasparini, R.; Pozzi, T.; Montomoli, E.; Fragapane, E.; Senatore, F.; Minutello, M.; Podda, A.

2001-01-01

Three-hundred and eight outpatient elderly subjects (≥ 65 years) were randomly assigned to receive the MF59-adjuvanted influenza vaccine (FLUAD; n = 204) or a conventional subunit influenza vaccine (AGRIPPAL S1; n = 104) in order to compare the safety and immunogenicity of the two vaccines. Although mild pain at the injection site was reported more frequently by subjects immunised with the adjuvanted vaccine, both vaccines were shown to be safe and well tolerated. The adjuvanted vaccine was more immunogenic as indicated by higher post-immunisation geometric mean titres (GMTs) and by higher proportions of subjects with post-immunisation ≥ four fold increases of antibody titres or subjects with ≥ 1/160 post-immunisation HI titres. These differences, statistically significant for all three strains after immunisation, indicated that, by addition of the MF59 adjuvant emulsion, conventional subunit influenza antigens acquire an enhanced immunogenicity without any clinically significant increase of their reactogenicity

Marketing paediatric influenza vaccination: results of a major metropolitan trial

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Van Buynder, Paul G.; Carcione, Dale; Rettura, Vince; Daly, Alison; Woods, Emily

2010-01-01

Please cite this paper as: Van Buynder et al. (2010) Marketing paediatric influenza vaccination: results of a major metropolitan trial. Influenza and Other Respiratory Viruses 5(1), 33–38. Objectives  After a cluster of rapidly fulminant influenza related toddler deaths in a Western Australian metropolis, children aged six to 59 months were offered influenza vaccination in subsequent winters. Some parental resistance was expected and previous poor uptake of paediatric influenza vaccination overseas was noted. A marketing campaign addressing barriers to immunization was developed to maximise uptake. Design  Advertising occurred in major statewide newspapers, via public poster displays and static ‘eye‐lite’ displays, via press releases, via a series of rolling radio advertisements, via direct marketing to child care centres, and via a linked series of web‐sites. Parents were subsequently surveyed to assess reasons for vaccination. Main Outcome Results  The campaign produced influenza vaccination coverage above that previously described elsewhere and led to a proportionate reduction in influenza notifications in this age group compared to previous seasons. Conclusions  Influenza in children comes with significant morbidity and some mortality. Paediatric influenza vaccination is safe, well tolerated and effective if two doses are given. A targeted media campaign can increase vaccine uptake if it reinforces the seriousness of influenza and addresses community ‘myths’ about influenza and influenza vaccine. The lessons learned enabling enhancements of similar programs elsewhere. PMID:21138538

Cost-effectiveness of adding vaccination with the AS04-adjuvanted human papillomavirus 16/18 vaccine to cervical cancer screening in Hungary

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Vokó Zoltán

2012-10-01

Full Text Available Abstract Background The cervical cancer screening program implemented in Hungary to date has not been successful. Along with screening, vaccination is an effective intervention to prevent cervical cancer. The aim of this study was to assess the cost-effectiveness of adding vaccination with the human papillomavirus 16/18 vaccine to the current cervical cancer screening program in Hungary. Methods We developed a cohort simulation state-transition Markov model to model the life course of 12-year-old girls. Eighty percent participation in the HPV vaccination program at 12 years of age was assumed. Transitional probabilities were estimated using data from the literature. Local data were used regarding screening participation rates, and the costs were estimated in US $. We applied the purchasing power parity exchange rate of 129 HUF/$ to the cost data. Only direct health care costs were considered. We used a 3.7% discount rate for both the cost and quality-adjusted life years (QALYs. The time horizon was 88 years. Results Inclusion of HPV vaccination at age 12 in the cervical cancer prevention program was predicted to be cost-effective. The incremental cost-effectiveness ratio (ICER of adding HPV vaccination to the current national cancer screening program was estimated to be 27 588 $/QALY. The results were sensitive to the price of the vaccine, the discount rate, the screening participation rate and whether herd immunity was taken into account. Conclusions Our modeling analysis showed that the vaccination of 12-year-old adolescent girls against cervical cancer with the AS04-adjuvanted human papillomavirus 16/18 vaccine would be a cost-effective strategy to prevent cervical cancer in Hungary.

Ethical considerations for vaccination programmes in acute humanitarian emergencies

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Hardie, Kate; Selgelid, Michael J; Waldman, Ronald J; Strebel, Peter; Rees, Helen; Durrheim, David N

2013-01-01

Abstract Humanitarian emergencies result in a breakdown of critical health-care services and often make vulnerable communities dependent on external agencies for care. In resource-constrained settings, this may occur against a backdrop of extreme poverty, malnutrition, insecurity, low literacy and poor infrastructure. Under these circumstances, providing food, water and shelter and limiting communicable disease outbreaks become primary concerns. Where effective and safe vaccines are available to mitigate the risk of disease outbreaks, their potential deployment is a key consideration in meeting emergency health needs. Ethical considerations are crucial when deciding on vaccine deployment. Allocation of vaccines in short supply, target groups, delivery strategies, surveillance and research during acute humanitarian emergencies all involve ethical considerations that often arise from the tension between individual and common good. The authors lay out the ethical issues that policy-makers need to bear in mind when considering the deployment of mass vaccination during humanitarian emergencies, including beneficence (duty of care and the rule of rescue), non-maleficence, autonomy and consent, and distributive and procedural justice. PMID:23599553

Experimental Vaccines against Chagas Disease: A Journey through History.

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Rodríguez-Morales, Olivia; Monteón-Padilla, Víctor; Carrillo-Sánchez, Silvia C; Rios-Castro, Martha; Martínez-Cruz, Mariana; Carabarin-Lima, Alejandro; Arce-Fonseca, Minerva

2015-01-01

Chagas disease, or American trypanosomiasis, which is caused by the protozoan parasite Trypanosoma cruzi, is primarily a vector disease endemic in 21 Latin American countries, including Mexico. Although many vector control programs have been implemented, T. cruzi has not been eradicated. The development of an anti-T. cruzi vaccine for prophylactic and therapeutic purposes may significantly contribute to the transmission control of Chagas disease. Immune protection against experimental infection with T. cruzi has been studied since the second decade of the last century, and many types of immunogens have been used subsequently, such as killed or attenuated parasites and new DNA vaccines. This primary prevention strategy appears feasible, effective, safe, and inexpensive, although problems remain. The objective of this review is to summarize the research efforts about the development of vaccines against Chagas disease worldwide. A thorough literature review was conducted by searching PubMed with the terms "Chagas disease" and "American trypanosomiasis" together with "vaccines" or "immunization". In addition, reports and journals not cited in PubMed were identified. Publications in English, Spanish, and Portuguese were reviewed.

Cost-effectiveness analysis of the introduction of rotavirus vaccine in Iran.

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Javanbakht, Mehdi; Moradi-Lakeh, Maziar; Yaghoubi, Mohsen; Esteghamati, Abdoulreza; Mansour Ghanaie, Roxana; Mahmoudi, Sussan; Shamshiri, Ahmad-Reza; Zahraei, Seyed Mohsen; Baxter, Louise; Shakerian, Sareh; Chaudhri, Irtaza; Fleming, Jessica A; Munier, Aline; Baradaran, Hamid R

2015-05-07

Although the mortality from diarrheal diseases has been decreasing dramatically in Iran, it still represents an important proportion of disease burden in children Rotavirus vaccines are among the most effective strategies against diarrheal diseases in specific epidemiological conditions. This study aimed to evaluate the cost-effectiveness of the introduction of rotavirus vaccine (3 doses of pentavalent RotaTeq (RV5)) in Iran, from the viewpoints of Iran's health system and society. The TRIVAC decision support model was used to calculate total incremental costs, life years (LYs) gained, and disability-adjusted life years (DALYs) averted due to the vaccination program. Necessary input data were collected from the most valid accessible sources as well as a systematic review and meta-analysis on epidemiological studies. We used WHO guidelines to estimate vaccination cost. An annual discount rate of 3% was considered for both health gain and costs. A deterministic sensitivity analysis was performed for testing the robustness of the models results. Our results indicated that total DALYs potentially lost due to rotavirus diarrhea within 10 years would be 138,161, of which 76,591 could be prevented by rotavirus vaccine. The total vaccination cost for 10 cohorts was estimated to be US$ 499.91 million. Also, US$ 470.61 million would be saved because of preventing outpatient visits and inpatient admissions (cost-saving from the society perspective). We estimated a cost per DALY averted of US$ 2868 for RV5 vaccination, which corresponds to a highly cost-effective strategy from the government perspective. In the sensitivity analysis, all scenarios tested were still cost-saving or highly cost-effective from the society perspective, except in the least favorable scenario and low vaccine efficacy and disease incidence scenario. Based on the findings, introduction of rotavirus vaccine is a highly cost-effective strategy from the government perspective. Introducing the vaccine to

Effects of the introduction of new vaccines in Guinea-Bissau on vaccine coverage, vaccine timeliness, and child survival: an observational study.

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Fisker, Ane B; Hornshøj, Linda; Rodrigues, Amabelia; Balde, Ibraima; Fernandes, Manuel; Benn, Christine S; Aaby, Peter

2014-08-01

In 2008, the GAVI Alliance funded the introduction of new vaccines (including pentavalent diphtheria-tetanus-pertussis [DTP] plus hepatitis B and Haemophilus influenzae type b antigens) in Guinea-Bissau. The introduction was accompanied by increased vaccination outreach services and a more restrictive wastage policy, including only vaccinating children younger than 12 months. We assessed coverage of all vaccines in the Expanded Program on Immunizations before and after the new vaccines' introduction, and the implications on child survival. This observational cohort study used data from the Bandim Health Project, which has monitored vaccination status and mortality in randomly selected village clusters in Guinea-Bissau since 1990. We assessed the change in vaccination coverage using cohort data from children born in 2007 and 2009; analysed the proportion of children who received measles vaccine after 12 months of age using data from 1999-2006; and compared child mortality after age 12 months in children who had received measles vaccine and those who had not using data from 1999 to 2006. The proportion of children who were fully vaccinated by 12 months of age was 53% (468 of 878) in the 2007 cohort and 53% (467 of 879) in the 2009 cohort (relative risk [RR] 1·00, 95% CI 0·89-1·11). Coverage of DTP-3 and pentavalent-3 increased from 73% (644 of 878) in 2007 to 81% (712 of 879) in 2009 (RR 1·10, 95% CI 1·04 -1·17); by contrast, the coverage of measles vaccination declined from 71% (620 of 878) to 66% (577 of 879; RR 0·93, 0·85-1·01). The effect of the changes was significantly different for DTP-3 coverage compared with measles vaccine coverage (p=0·002). After 12 months of age, the adjusted mortality rate ratio was 0·71 (95% CI 0·56-0·90) for children who had received measles vaccine compared with those who had not (0·59 [0·43-0·80] for girls and 0·87 [0·62-1·23] for boys). The introduction of the new vaccination programme in 2008 was associated with

Vaccine Hesitancy: In Search of the Risk Communication Comfort Zone.

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Greenberg, Joshua; Dubé, Eve; Driedger, Michelle

2017-03-03

This paper reports the findings of a national online survey to parents of children aged 5 and younger. The objectives of the study were to assess parental understanding of childhood immunizations, identify sources of information that they trust for vaccine-related content, assess where parents with young children stand on the key issues in the public debate about vaccination, and identify which risk communication messages are most effective for influencing the behaviours of vaccine hesitant parents. A total of 1,000 surveys (closed and open-ended questions) were administered in November 2015 using the Angus Reid Forum Panel, a key consumer panel consisting of approximately 150,000 Canadian adults aged 18 and older, spread across all geographic regions of Canada. Approximately 92% of the Canadian parents surveyed consider vaccines safe and effective, and trust doctors and public health officials to provide timely and credible vaccine-related information. However, a concerning number of them either believe or are uncertain whether there is a link between vaccines and autism (28%), worry that vaccines might seriously harm their children (27%), or believe the pharmaceutical industry is behind the push for mandatory immunization (33%). Moreover, despite the common assumption that social media are becoming the go-to source of health news and information, most parents still rely on traditional media and official government websites for timely and credible information about vaccines and vaccine preventable diseases, particularly during community-based disease outbreaks. Finally, parents reported high levels of support for pro-vaccine messaging that has been demonstrated in previous research to have little to no positive impact on behaviour change, and may even be counterproductive. The study's results are highly relevant in a context where public health officials are expending significant resources to increase rates of childhood immunization and combat vaccine

Rift Valley Fever Vaccine Virus Clone 13 Is Able to Cross the Ovine Placental Barrier Associated with Foetal Infections, Malformations, and Stillbirths.

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Birgit Makoschey

2016-03-01

Full Text Available Rift Valley fever virus (RVFV is a mosquito-borne pathogen that affects domesticated ruminants and occasionally humans. Classical RVF vaccines are based on formalin-inactivated virus or the live-attenuated Smithburn strain. The inactivated vaccine is highly safe but requires multiple administrations and yearly re-vaccinations. Although the Smithburn vaccine provides solid protection after a single vaccination, this vaccine is not safe for pregnant animals. An alternative live-attenuated vaccine, named Clone 13, carries a large natural deletion in the NSs gene which encodes the major virulence factor of the virus. The Clone 13 vaccine was previously shown to be safe for young lambs and calves. Moreover, a study in pregnant ewes suggested that the vaccine could also be applied safely during gestation. To anticipate on a possible future incursion of RVFV in Europe, we have evaluated the safety of Clone 13 for young lambs and pregnant ewes. In line with the guidelines from the World Organisation for Animal health (Office International des Epizooties, OIE and regulations of the European Pharmacopeia (EP, these studies were performed with an overdose. Our studies with lambs showed that Clone 13 dissemination within vaccinated animals is very limited. Moreover, the Clone 13 vaccine virus was not shed nor spread to in-contact sentinels and did not revert to virulence upon animal-to-animal passage. Importantly, a large experiment with pregnant ewes demonstrated that the Clone 13 virus is able to spread to the fetus, resulting in malformations and stillbirths. Altogether, our results suggest that Clone 13 can be applied safely in lambs, but that caution should be taken when Clone 13 is used in pregnant animals, particularly during the first trimester of gestation.

Rift Valley Fever Vaccine Virus Clone 13 Is Able to Cross the Ovine Placental Barrier Associated with Foetal Infections, Malformations, and Stillbirths

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Makoschey, Birgit; van Kilsdonk, Emma; Hubers, Willem R.; Vrijenhoek, Mieke P.; Smit, Marianne; Wichgers Schreur, Paul J.; Kortekaas, Jeroen; Moulin, Véronique

2016-01-01

Rift Valley fever virus (RVFV) is a mosquito-borne pathogen that affects domesticated ruminants and occasionally humans. Classical RVF vaccines are based on formalin-inactivated virus or the live-attenuated Smithburn strain. The inactivated vaccine is highly safe but requires multiple administrations and yearly re-vaccinations. Although the Smithburn vaccine provides solid protection after a single vaccination, this vaccine is not safe for pregnant animals. An alternative live-attenuated vaccine, named Clone 13, carries a large natural deletion in the NSs gene which encodes the major virulence factor of the virus. The Clone 13 vaccine was previously shown to be safe for young lambs and calves. Moreover, a study in pregnant ewes suggested that the vaccine could also be applied safely during gestation. To anticipate on a possible future incursion of RVFV in Europe, we have evaluated the safety of Clone 13 for young lambs and pregnant ewes. In line with the guidelines from the World Organisation for Animal health (Office International des Epizooties, OIE) and regulations of the European Pharmacopeia (EP), these studies were performed with an overdose. Our studies with lambs showed that Clone 13 dissemination within vaccinated animals is very limited. Moreover, the Clone 13 vaccine virus was not shed nor spread to in-contact sentinels and did not revert to virulence upon animal-to-animal passage. Importantly, a large experiment with pregnant ewes demonstrated that the Clone 13 virus is able to spread to the fetus, resulting in malformations and stillbirths. Altogether, our results suggest that Clone 13 can be applied safely in lambs, but that caution should be taken when Clone 13 is used in pregnant animals, particularly during the first trimester of gestation. PMID:27031621

Evolution of M. bovis BCG Vaccine: Is Niacin Production Still a Valid Biomarker?

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Sarman Singh

2015-01-01

Full Text Available BCG vaccine is usually considered to be safe though rarely serious complications have also been reported, often incriminating contamination of the seed strain with pathogenic Mycobacterium tuberculosis. In such circumstances, it becomes prudent to rule out the contamination of the vaccine seed. M. bovis BCG can be confirmed by the absence of nitrate reductase, negative niacin test, and resistance to pyrazinamide and cycloserine. Recently in India, some stocks were found to be niacin positive which led to a national controversy and closer of a vaccine production plant. This prompted us to write this review and the comparative biochemical and genotypic studies were carried out on the these contentious vaccine stocks at the Indian vaccine plant and other seeds and it was found that some BCG vaccine strains and even some strains of M. bovis with eugenic-growth characteristics mainly old laboratory strains may give a positive niacin reaction. Most probably, the repeated subcultures lead to undefined changes at the genetic level in these seed strains. These changing biological characteristics envisage reevaluation of biochemical characters of existing BCG vaccine seeds and framing of newer guidelines for manufacturing, production, safety, and effectiveness of BCG vaccine.

Cost-effectiveness of human papillomavirus vaccination and cervical cancer screening in Thailand.

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Sharma, M; Ortendahl, J; van der Ham, E; Sy, S; Kim, J J

2012-01-01

To assess the health and economic outcomes of various screening and vaccination strategies for cervical cancer prevention. Cost-effectiveness analysis from a societal perspective. Thailand. Females aged 9 years and older. Using a mathematical model of human papillomavirus (HPV) infection and cervical cancer, calibrated to epidemiological data from Thailand, we estimated the cost-effectiveness of pre-adolescent HPV vaccination, screening [visual inspection with acetic acid (VIA), HPV DNA testing, and cytology] between one and five times per lifetime in adulthood, and combined pre-adolescent vaccination and screening. Vaccine efficacy, coverage, cost, and screening frequency were varied in sensitivity analyses. Incremental cost-effectiveness ratios, expressed as cost per year of life saved (YLS). Assuming lifelong efficacy and 80% coverage, pre-adolescent HPV vaccination alone was projected to reduce the lifetime risk of cervical cancer by 55%, which was greater than any strategy of screening alone. When cost per vaccinated girl was I$10 (approximately $2 per dose) or less, HPV vaccination alone was cost saving. Pre-adolescent vaccination and HPV DNA testing five times per lifetime, starting at age 35 years, reduced the lifetime cervical cancer risk by 70%, and had a cost-effectiveness ratio less than Thailand's GDP per capita (I$8100), provided the cost per vaccinated girl was I$200 or less. Low cost pre-adolescent HPV vaccination followed by HPV screening five times per lifetime is an efficient strategy for Thailand. Costs may need to be lower, however, for this strategy to be affordable. If vaccination is not feasible, HPV DNA testing five times per lifetime is efficient. © 2011 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2011 RCOG.