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Norovirus (NoV) infection is a major cause of gastroenteritis worldwide. The virus poses great challenges in developing vaccines with broad immune protection due to its genetic and antigenic diversity. To date, there are no approved NoV vaccines for clinical use. Here, we aimed to develop a broad-acting quadrivalent NoV vaccine based on a chimpanzee adenovirus vector, AdC68, carrying the major capsid protein (VP1) of noroviral GI and GII genotypes. Compared to intramuscular (i.m.), intranasal (i.n.), or other prime-boost immunization regimens (i.m. + i.m., i.m. + i.n., i.n. + i.m.), AdC68-GI.1-GII.3 (E1)-GII.4-GII.17 (E3), administered via i.n. + i.n. induced higher titers of serum IgG antibodies and higher IgA antibodies in bronchoalveolar lavage fluid (BALF) and saliva against the four homologous VP1s in mice. It also significantly stimulated the production of blocking antibodies against the four genotypes. In response to re-stimulation with virus-like particles (VLP)-GI.1, VLP-GII.3, VLP-GII.4, and VLP-GII.17, the quadrivalent vaccine administered according to the i.n. + i.n. regimen effectively triggered specific cell-mediated immune responses, primarily characterized by IFN-γ secretion. Furthermore, the preparation of this novel quadrivalent NoV vaccine requires only a single recombinant adenovirus to provide broad preventive immunity against the major GI/GII epidemic strains, making it a promising vaccine candidate for further development. [ABSTRACT FROM AUTHOR]

Relevance. Seasonal flu vaccination is still the most effective way to protect against flu viruses and help to reduce the burden of flu illnesses. Another possible benefit is the impact of yearly vaccines on severity of breakthrough infection. In this regard, the issue of choosing safe vaccine with high immunogenicity becomes relevant.Aims. To evaluate the prophylactic efficacy of inactivated seasonal flu vaccines (quadrivalent subunit vaccine with adjuvant and trivalent vaccine) and reactogenicity of quadrivalent vaccine.Materials and methods. 491 cases were included in our study: 152 cases received adjuvanted quadrivalent subunit flu vaccine «Grippol Quadrivalent», 118 cases received trivalent inactivated flu vaccine and 221 cases who have received no vaccinations during 2018–2019 epidemic season.Results. inactivated vaccines showed high prophylactic efficacy in preventing seasonal influenza. Incidence of influenza and other viral respiratory disease cases was lowest in «Grippol Quadrivalent» group. Breakthrough influenza cases in individuals vaccinated with inactivated vaccine were predominantly mild, no severe cases were reported. The early post-vaccination period in «Grippol Quadrivalent» group showed no variation in adverse events with other vaccines.Conclusion. Adjuvanted quadrivalent subunit flu vaccine was the most efficacious in preventing influenza in 2018–2019 epidemic season.

Influenza is a highly contagious viral infection and poses a serious burden, especially for children under 5 years of age due to an increased risk of severe illness and hospitalization. Influenza-related infant mortality during the pre-Covid period was reported annually. The highest mortality rate was regularly recorded among young children and especially children under the age of 6 months. Influenza vaccination in young children has been proven to be safe and effective. Influenza vaccination of young children not only protects this vulnerable age group, but is also an important way to reduce the transmission of influenza to others at risk, as well as reduce the use of healthcare services, including the use of antibiotics. Immunization against influenza in the current epidemiological conditions is especially relevant, since during the ongoing COVID-19 pandemic, it is impossible to predict the intensity and timing of the upcoming influenza seasonal rise. To prevent influenza in children, any licensed influenza vaccine that meets the indications is used, however, in modern conditions, the priority in influenza prevention is the use of quadrivalent vaccines that ensure the development of the most stable immune response against key strains of influenza viruses. Quadrivalent influenza vaccines include two influenza B strains of the Yamagata and Victoria B lines in addition to influenza A strains (H1N1 and H3N2). Studies have shown that immunization with the quadrivalent vaccine, including in young children, is well tolerated and effectively protects against any circulating and antigenically matched strains of influenza viruses. Russian-made quadrivalent inactivated full-cycle influenza vaccine for the prevention of seasonal influenza is the first quadrivaccine in the Russian Federation approved for use in influenza immunization of children from 6 months of age and pregnant women. The vaccine complies with all World Health Organization recommendations on the composition and amount of hemagglutinin of an influenza virus strain – it contains 15 μg of influenza virus hemagglutinin of each strain (А(N1N1), A(N3N2), B line Yamagata, B line Victoria); does not contain immunomodulators, adjuvants and preservatives; meets the immunogenicity criteria for inactivated influenza vaccines adopted in the European Union and the Russian Federation.

Abstract Introduction Available human papillomavirus (HPV) vaccines could have an important primary role in cervical cancer prevention once their long-term immunogenicity and safety are evaluated at the population level. The aim of this study was to optimize an assay to be used in evaluating the long-term durability of HPV vaccine response following a pilot vaccination of adolescent girls in Ghana. Methods A rapid, high-throughput, indirect enzyme-linked immunosorbent assay (ELISA) was optimized for the detection and quantitation of anti-HPV L1 (late expression protein: types 6, 11, 16 and 18) immunoglobulin G (IgG) in human serum (n = 89). The utility of the assay was demonstrated using serum collected from a cohort of pre-adolescent girls (n = 49) previously vaccinated with a quadrivalent vaccine and non-immune serum obtained from age-matched controls (n = 40). Results The assay showed good discrimination of antibody levels between cases and control sera: seroprevalence of anti-HPV IgG antibodies was significantly higher among vaccinated than unvaccinated girls for both HPV-16 (63.3% vs. 12.5%; p

This study aimed to assess human papillomavirus (HPV) vaccine effectiveness (VE) against both vaccine-type and nonvaccine-type high-risk HPV (hrHPV) infection, and duration of protection in United States. The study population was female participants aged 18–35 years with an HPV vaccination history and genital testing for HPV from the National Health and Nutrition Examination Survey, 2007–2016. Participants vaccinated before sexual debut were assessed against 13 nonvaccine-type hrHPV infection including 31/33/35/39/45/51/52/56/58/59/68/73/82. Multivariable logistic regression was used to estimate VE overall, by age at diagnosis, time since vaccination and lifetime sexual partners. A total of 3866 women were included in the analysis, with 23.3% (95% CI 21.3%–25.4%) having been vaccinated (≥1 dose). VE against vaccine-type HPV18/16/11/6 infection was 58% overall, which was mainly driven by those aged 18–22 years (VE = 64%) and 23–27 years (65%). Among participants aged 18–22 years vaccinated before sexual debut, the VE was 47% (23%–64%) against 13 nonvaccine-type hrHPV and 61% (95% CI 36%–77%) against 5 selected nonvaccine-type hrHPV35/39/52/58/59. Both direct effectiveness and cross-protection maintained effective for 5–10 years post vaccination. We also found the prevalence of ever diagnosed cervical cancer among vaccinated was significantly lower (0.46%, 4/874) than that among unvaccinated participants (1.27%, 38/2992). These findings highlight the potential of significant reduction of cervical cancer following the universal HPV vaccination programme. [ABSTRACT FROM AUTHOR]

This study aimed to assess human papillomavirus (HPV) vaccine effectiveness (VE) against both vaccine-type and nonvaccine-type high-risk HPV (hrHPV) infection, and duration of protection in United States. The study population was female participants aged 18–35 years with an HPV vaccination history and genital testing for HPV from the National Health and Nutrition Examination Survey, 2007–2016. Participants vaccinated before sexual debut were assessed against 13 nonvaccine-type hrHPV infection including 31/33/35/39/45/51/52/56/58/59/68/73/82. Multivariable logistic regression was used to estimate VE overall, by age at diagnosis, time since vaccination and lifetime sexual partners. A total of 3866 women were included in the analysis, with 23.3% (95% CI 21.3%–25.4%) having been vaccinated (≥1 dose). VE against vaccine-type HPV18/16/11/6 infection was 58% overall, which was mainly driven by those aged 18–22 years (VE = 64%) and 23–27 years (65%). Among participants aged 18–22 years vaccinated before sexual debut, the VE was 47% (23%–64%) against 13 nonvaccine-type hrHPV and 61% (95% CI 36%–77%) against 5 selected nonvaccine-type hrHPV35/39/52/58/59. Both direct effectiveness and cross-protection maintained effective for 5–10 years post vaccination. We also found the prevalence of ever diagnosed cervical cancer among vaccinated was significantly lower (0.46%, 4/874) than that among unvaccinated participants (1.27%, 38/2992). These findings highlight the potential of significant reduction of cervical cancer following the universal HPV vaccination programme. [ABSTRACT FROM AUTHOR]

Influenza affects all age groups, but the risk of hospitalization and death due to influenza is strongly age-related and is at its highest among the elderly aged 65 years and older. The objective of this study is to compare the differences in influenza-associated disease burden under three different influenza vaccination strategies—the standard-dose quadrivalent influenza vaccine (QIV), high-dose QIV (HD-QIV), and MF59®-adjuvanted QIV (aQIV)—for the elderly population aged 65 years and older in South Korea. A one-year decision-tree model was developed to compare influenza disease burdens. The input data for the model were obtained from published literature reviews and surveillance data from the Korea Disease Control and Prevention Agency (KDCA). The analysis indicated that aQIV is more effective than QIV, preventing 35,390 influenza cases, 1602 influenza-associated complications, 709 influenza-associated hospitalizations, and 145 influenza-associated deaths annually. Additionally, aQIV, when compared to HD-QIV, also reduced the influenza-associated burden of disease, preventing 7247 influenza cases, 328 influenza-associated complications, 145 influenza-associated hospitalizations, and 30 influenza-associated deaths annually. Switching the vaccination strategy from QIV to aQIV is predicted to reduce the influenza-associated disease burden for the elderly in South Korea. The public health gains from aQIV and HD-QIV are expected to be comparable. Future studies comparing the effectiveness of the vaccines will further inform future vaccination strategies for the elderly in South Korea. [ABSTRACT FROM AUTHOR]

We evaluated the cost-utility of replacing trivalent influenza vaccine (TIV) with quadrivalent influenza vaccine (QIV) in the current target populations in Uruguay. An existing decision-analytic static cost-effectiveness model was adapted for Uruguay. The population was stratified into age groups. Costs and outcomes were estimated for an average influenza season, based on observed rates from 2013 to 2019 inclusive. Introducing QIV instead of TIV in Uruguay would avoid around 740 additional influenza cases, 500 GP consultations, 15 hospitalizations, and three deaths, and save around 300 workdays, for the same vaccination coverage during an average influenza season. Most of the influenza-related consultations and hospitalizations would be avoided among children ≤4 and adults ≥65 years of age. Using QIV rather than TIV would cost an additional ~US$729,000, but this would be partially offset by savings in consultations and hospitalization costs. The incremental cost per quality-adjusted life-year (QALY) gained with QIV would be in the order of US$18,000 for both the payor and societal perspectives, for all age groups, and around US$12,000 for adults ≥65 years of age. The main drivers influencing the incremental cost-effectiveness ratio were the vaccine efficacy against the B strains and the percentage of match each season with the B strain included in TIV. Probabilistic sensitivity analysis showed that switching to QIV would provide a favorable cost-utility ratio for 50% of simulations at a willingness-to-pay per QALY of US$20,000. A switch to QIV is expected to be cost-effective for the current target populations in Uruguay, particularly for older adults.

This study aimed to investigate the public health and economic benefit of using a quadrivalent influenza vaccine (QIV) instead of a trivalent influenza vaccine (TIV) in past seasons in Paraguay. The budget impact of switching from TIV to QIV in the Immunization Program was also evaluated. The adapted model includes two modules. The first compared retrospectively Health and Economic outcomes resulting from the use of QIV instead of TIV. The second forecast the spending and savings that would be associated with the switch from TIV to QIV. Our findings estimate that the switch from TIV to QIV during the seasons 2012 to 2017 could have prevented around 2,600 influenza cases, 67 hospitalizations and 10 deaths. An alternative scenario using standardized estimates of the burden of influenza showed that 234 influenza-related hospitalizations and 29 deaths could have been prevented. The estimated annual budget impact of a full switch from TIV to QIV was around USD1,6 million both from the payer and societal perspectives. Those results are mainly driven by vaccine prices and coverage rate. In sum, this manuscript describes how the use of QIV instead of TIV could have prevented influenza cases and subsequent complications that led to hospitalizations and deaths. This could have generated savings for the health system and society, offsetting part of the additional investment needed to switch from TIV to QIV.

Standard-dose quadrivalent influenza vaccines (QIV) are designed to provide protection against all four influenza strains. Adjuvanted QIV (aQIV), indicated for individuals aged 65+ years, combines MF59® adjuvant (an oil-in-water emulsion of squalene oil) with a standard dose of antigen, and is designed to produce stronger and longer immune response, especially in the elderly where immunosenescence reduces vaccine effectiveness. This study evaluated the cost-effectiveness of aQIV vs. egg-based standard-dose QIV (QIVe) in the elderly population, from the payer and societal perspective in Spain. A dynamic transmission model, which accounts for herd protection, was used to predict the number of medically attended infections in Spain. A decision tree structure was used to forecast influenza-related costs and benefits. Influenza-related probabilities of outpatient visit, hospitalization, work absenteeism, mortality, and associated utilities and costs were extracted from Spanish and European published literature. Relative vaccine effectiveness (rVE) was sourced from two different meta-analyses: the first meta-analysis was informed by laboratory-confirmed influenza studies only, resulting in a rVE = 34.6% (CI95% 2–66%) in favor of aQIV; the second meta-analysis included real world evidence influenza-related medical encounters outcomes, resulting in a rVE = 13.9% (CI95% 4.2–23.5%) in benefit of aQIV. All costs were expressed in 2021 euros. Results indicate that replacing QIVe with aQIV in the Spanish elderly population would prevent on average 43,664 influenza complicated cases, 1111 hospitalizations, and 569 deaths (with a rVE = 34.6%) or 19,104 influenza complicated cases, 486 hospitalizations, and 252 deaths (with a rVE = 13.9%). When the rVE of aQIV vs. QIVe is 34.6%, the incremental cost per quality adjusted life years (QALY) gained was €2240 from the payer; from the societal perspective, aQIV was cost saving compared with QIVe. If the rVE was 13.9%, the incremental cost per QALY was €6694 and €3936 from the payer and societal perspective, respectively. Sensitivity analyses validated the robustness of these findings. Results indicate that replacing QIVe with aQIV in the Spanish elderly population is a cost-effective strategy for the Spanish healthcare system. [ABSTRACT FROM AUTHOR]

Neuromyotonia is a rare peripheral nerve hyperexcitability syndrome often associated with antibodies directed against contactin-associated protein-like 2 and leucine-rich, glioma inactivated 1. The quadrivalent human papilloma virus vaccine Gardasil®, first approved in 2006, is known to be a highly effective prophylaxis against papillomavirus types 6, 11, 16, and 18. Molecularly, this non-infectious recombinant vaccine is based on purified L1 proteins from the human papilloma virus capsid. Since the approval of this vaccine, several studies have investigated its safety regarding the occurrence of autoimmune conditions following application. Here, we present the first case of neuromyotonia with active Gadolinium enhancing demyelinating central nervous system lesions following vaccination with Gardasil®. [ABSTRACT FROM AUTHOR]

Introduction: Available human papillomavirus (HPV) vaccines could have an important primary role in cervical cancer prevention once their long-term immunogenicity and safety are evaluated at the population level. The aim of this study was to optimize an assay to be used in evaluating the long-term durability of HPV vaccine response following a pilot vaccination of adolescent girls in Ghana.Methods: A rapid, high-throughput, indirect enzyme-linked immunosorbent assay (ELISA) was optimized for the detection and quantitation of anti-HPV L1 (late expression protein: types 6, 11, 16 and 18) immunoglobulin G (IgG) in human serum (n = 89). The utility of the assay was demonstrated using serum collected from a cohort of pre-adolescent girls (n = 49) previously vaccinated with a quadrivalent vaccine and non-immune serum obtained from age-matched controls (n = 40).Results: The assay showed good discrimination of antibody levels between cases and control sera: seroprevalence of anti-HPV IgG antibodies was significantly higher among vaccinated than unvaccinated girls for both HPV-16 (63.3% vs. 12.5%; p < 0.001) and HPV-18 (34.7% vs. 20.0%; p = 0.042), respectively. Thirty-six months after receiving the third dose of vaccine, significantly higher mean anti-HPV-16 (0.618 vs. 0.145), anti-HPV-18 (0.323 vs. 0.309), and anti-HPV-6 (1.371 vs. 0.981) antibody levels were measured, compared to unvaccinated girls (all p < 0.05). A correlation between optical density and antibody activity indicated assay sensitivity to increasing levels of antibody activity.Conclusion: We have successfully optimized and implemented a robust and sensitive assay for the evaluation of antibody responses among immunized adolescent girls for monitoring future large-scale HPV vaccination studies in low-income settings. Our results demonstrated greater immunoglobulin G antibody activity within serum drawn from adolescent girls immunized 36 months prior. [ABSTRACT FROM AUTHOR]

A fully government-funded human papillomavirus (HPV) vaccination program started in 2007 in Spain (only 11–14-year-old girls). The first of those vaccinated cohorts, with the quadrivalent vaccine (Gardasil), turned 25 years old in 2018, the age at which cervical cancer screening begins in Spain. The current study could provide the first evidence about the effectiveness of the quadrivalent vaccine against HPV in Spain and the influence of age of vaccination. The present ambispective cohort study, which was conducted on 790 women aged 25 and 26 years old, compares the rate of HPV prevalence and cytologic anomaly according to the vaccination status. The overall infection rate was 40.09% (vaccinated group) vs. 40.6% (non-vaccinated group). There was a significant reduction in the prevalence of HPV 6 (0% vs. 1.3%) and 16 (2.4% vs. 6.1%), and in the prevalence of cytological abnormalities linked to HPV16: Atypical Squamous Cells of Undetermined Significance (ASCUS) (2.04% vs. 14%), Low-grade Squamous Intraepithelial Lesions (LSIL) (2.94% vs. 18.7%) and High-grade Squamous Intraepithelial Lesion (HSIL) (0% vs. 40%), in the vaccinated group vs. the non-vaccinated group. Only one case of HPV11 and two cases of HPV18 were detected. The vaccine effectively reduces the prevalence of vaccine genotypes and cytological anomalies linked to these genotypes. [ABSTRACT FROM AUTHOR]

According to requirements of WHO, the trivalent influenza vaccines (TIV) have to contain antigens of two influenza A strains (A/H1N1, A/H3N2) and one influenza B strain which can be presented by antigens of a virus of lineages Yamagata or Victoria. In a season of 2017/2018 the discrepancy of the vaccinal and circulating influenza B strains was noted that caused decrease in effectiveness of vaccination, especially at children’s age when the frequency of detection of influenza B is higher, than in other age groups. Now in the Russian Federation it is registered, in addition to TIV, quadrivalent vaccine (QIV) manufactured in the Russian Federation and including antigens of influenza B viruses of the two lineages.The purpose of work was assessment of the cost-effectiveness of QIV in comparison with TIV at children of preschool age on the basis of epidemiological data on the Russian Federation for a season of 2017/2018.Material and methods. The analysis was carried out by a modeling method from a health care system and societal perspective taking into account epidemiological data on the Russian Federation and the European data on effectiveness of TIV at citizens of various age. Indirect effect of vaccination was not considered. The cost of the TIV and QIV (Grippol plus and Grippol quadrivalent, respectively) corresponded to the registered price including VAT.Results. The analysis showed that use QIV instead of TIV for children of preschool age in an epidemiological season of 2017/2018 would allow to increase quantity of the prevented influenza cases by 17.1%. The prevented indirect costs exceed the prevented direct medical costs. The incremental cost-effectiveness ratio (ICER) is 1042.65-1093.7 thousand rubles/QALY in the analysis from the health care system perspective and 124.50-267.91 thousand rubles/QALY in the analysis from the societal perspective.Conclusions. Vaccination against influenza of children of preschool age in the Russian Federation in a season of 2017/2018 with quadrivalent vaccine would allow to increase significantly the number of the prevented cases of disease and could be considered as economically highly effective intervention. Reduction of vaccine price less, than for 5% in comparison with the registered price would allow to avoid completely additional budget burden.

Considered a highly prevalent infection worldwide, the human papilloma virus (HPV) is a viral DNA capable of infecting the genital mucosa, in addition to having potential oncogenic activity. It known if, therefore, that cervical cancer can be caused by some types of HPV, among them the subtypes HPV- 16 and HPV-18, considered the most frequent in women, therefore, responsible for about 70% of cervical cancers. When dealing with a public health problem, vaccine development it is considered a very effective and most cost-effective prophylactic method. In this context, the quadrivalent vaccine was adopted and approved by the Ministry of Health has been shown to be a good option for controlling this infectious disease. The HPV vaccine is prepared from analogous viral particles, produced by recombinant technology, from the L1 protein of the viral capsid of the HPV types, being able to generate an immune response. Given the above, this literature review aims to present the general characteristics of HPV viruses and associate them with cervical-vaginal lesions, presenting the immunological aspects of the quadrivalent vaccine and its effectiveness in preventing cervical cancer. [ABSTRACT FROM AUTHOR]

Influenza affects all age groups, but the risk of hospitalization and death due to influenza is strongly age-related and is at its highest among the elderly aged 65 years and older. The objective of this study is to compare the differences in influenza-associated disease burden under three different influenza vaccination strategies—the standard-dose quadrivalent influenza vaccine (QIV), high-dose QIV (HD-QIV), and MF59®-adjuvanted QIV (aQIV)—for the elderly population aged 65 years and older in South Korea. A one-year decision-tree model was developed to compare influenza disease burdens. The input data for the model were obtained from published literature reviews and surveillance data from the Korea Disease Control and Prevention Agency (KDCA). The analysis indicated that aQIV is more effective than QIV, preventing 35,390 influenza cases, 1602 influenza-associated complications, 709 influenza-associated hospitalizations, and 145 influenza-associated deaths annually. Additionally, aQIV, when compared to HD-QIV, also reduced the influenza-associated burden of disease, preventing 7247 influenza cases, 328 influenza-associated complications, 145 influenza-associated hospitalizations, and 30 influenza-associated deaths annually. Switching the vaccination strategy from QIV to aQIV is predicted to reduce the influenza-associated disease burden for the elderly in South Korea. The public health gains from aQIV and HD-QIV are expected to be comparable. Future studies comparing the effectiveness of the vaccines will further inform future vaccination strategies for the elderly in South Korea.

Standard-dose quadrivalent influenza vaccines (QIV) are designed to provide protection against all four influenza strains. Adjuvanted QIV (aQIV), indicated for individuals aged 65+ years, combines MF59® adjuvant (an oil-in-water emulsion of squalene oil) with a standard dose of antigen, and is designed to produce stronger and longer immune response, especially in the elderly where immunosenescence reduces vaccine effectiveness. This study evaluated the cost-effectiveness of aQIV vs. egg-based standard-dose QIV (QIVe) in the elderly population, from the payer and societal perspective in Spain. A dynamic transmission model, which accounts for herd protection, was used to predict the number of medically attended infections in Spain. A decision tree structure was used to forecast influenza-related costs and benefits. Influenza-related probabilities of outpatient visit, hospitalization, work absenteeism, mortality, and associated utilities and costs were extracted from Spanish and European published literature. Relative vaccine effectiveness (rVE) was sourced from two different meta-analyses: the first meta-analysis was informed by laboratory-confirmed influenza studies only, resulting in a rVE = 34.6% (CI95% 2–66%) in favor of aQIV; the second meta-analysis included real world evidence influenza-related medical encounters outcomes, resulting in a rVE = 13.9% (CI95% 4.2–23.5%) in benefit of aQIV. All costs were expressed in 2021 euros. Results indicate that replacing QIVe with aQIV in the Spanish elderly population would prevent on average 43,664 influenza complicated cases, 1111 hospitalizations, and 569 deaths (with a rVE = 34.6%) or 19,104 influenza complicated cases, 486 hospitalizations, and 252 deaths (with a rVE = 13.9%). When the rVE of aQIV vs. QIVe is 34.6%, the incremental cost per quality adjusted life years (QALY) gained was €2240 from the payer; from the societal perspective, aQIV was cost saving compared with QIVe. If the rVE was 13.9%, the incremental cost per QALY was €6694 and €3936 from the payer and societal perspective, respectively. Sensitivity analyses validated the robustness of these findings. Results indicate that replacing QIVe with aQIV in the Spanish elderly population is a cost-effective strategy for the Spanish healthcare system.

Neuromyotonia is a rare peripheral nerve hyperexcitability syndrome often associated with antibodies directed against contactin-associated protein-like 2 and leucine-rich, glioma inactivated 1. The quadrivalent human papilloma virus vaccine Gardasil®, first approved in 2006, is known to be a highly effective prophylaxis against papillomavirus types 6, 11, 16, and 18. Molecularly, this non-infectious recombinant vaccine is based on purified L1 proteins from the human papilloma virus capsid. Since the approval of this vaccine, several studies have investigated its safety regarding the occurrence of autoimmune conditions following application. Here, we present the first case of neuromyotonia with active Gadolinium enhancing demyelinating central nervous system lesions following vaccination with Gardasil®.

Norovirus (NoV) infection is a major cause of gastroenteritis worldwide. The virus poses great challenges in developing vaccines with broad immune protection due to its genetic and antigenic diversity. To date, there are no approved NoV vaccines for clinical use. Here, we aimed to develop a broad-acting quadrivalent NoV vaccine based on a chimpanzee adenovirus vector, AdC68, carrying the major capsid protein (VP1) of noroviral GI and GII genotypes. Compared to intramuscular (i.m.), intranasal (i.n.), or other prime-boost immunization regimens (i.m. ​+ ​i.m., i.m. ​+ ​i.n., i.n. ​+ ​i.m.), AdC68-GI.1-GII.3 (E1)-GII.4-GII.17 (E3), administered via i.n. ​+ ​i.n. induced higher titers of serum IgG antibodies and higher IgA antibodies in bronchoalveolar lavage fluid (BALF) and saliva against the four homologous VP1s in mice. It also significantly stimulated the production of blocking antibodies against the four genotypes. In response to re-stimulation with virus-like particles (VLP)-GI.1, VLP-GII.3, VLP-GII.4, and VLP-GII.17, the quadrivalent vaccine administered according to the i.n. ​+ ​i.n. regimen effectively triggered specific cell-mediated immune responses, primarily characterized by IFN-γ secretion. Furthermore, the preparation of this novel quadrivalent NoV vaccine requires only a single recombinant adenovirus to provide broad preventive immunity against the major GI/GII epidemic strains, making it a promising vaccine candidate for further development., Competing Interests: Declaration of competing interest All authors declare that there are no competing interests., (Copyright © 2024 The Authors. Publishing services by Elsevier B.V. All rights reserved.)

A fully government-funded human papillomavirus (HPV) vaccination program started in 2007 in Spain (only 11–14-year-old girls). The first of those vaccinated cohorts, with the quadrivalent vaccine (Gardasil), turned 25 years old in 2018, the age at which cervical cancer screening begins in Spain. The current study could provide the first evidence about the effectiveness of the quadrivalent vaccine against HPV in Spain and the influence of age of vaccination. The present ambispective cohort study, which was conducted on 790 women aged 25 and 26 years old, compares the rate of HPV prevalence and cytologic anomaly according to the vaccination status. The overall infection rate was 40.09% (vaccinated group) vs. 40.6% (non-vaccinated group). There was a significant reduction in the prevalence of HPV 6 (0% vs. 1.3%) and 16 (2.4% vs. 6.1%), and in the prevalence of cytological abnormalities linked to HPV16: Atypical Squamous Cells of Undetermined Significance (ASCUS) (2.04% vs. 14%), Low-grade Squamous Intraepithelial Lesions (LSIL) (2.94% vs. 18.7%) and High-grade Squamous Intraepithelial Lesion (HSIL) (0% vs. 40%), in the vaccinated group vs. the non-vaccinated group. Only one case of HPV11 and two cases of HPV18 were detected. The vaccine effectively reduces the prevalence of vaccine genotypes and cytological anomalies linked to these genotypes.

배경 Adults aged 65 years and older (elderly) experience higher influenza-related morbidity and mortality each year than other age groups. Age-related immunosenescence is one of the factors that potentially reduces immune response to the vaccination. Several vaccines have been developed for the elderly in- cluding adjuvanted quadrivalent influenza vaccines (aQIV) and high-dose quadrivalent influenza vaccines (HD-QIV). The objective of this study is to compare the difference in influenza-associated disease bur- den under three different influenza vaccination strategies (quadrivalent influenza vaccines (QIVe), HD-QIV and aQIV)) for the elderly population in South Korea. 방법 One-year decision tree model (figure 1) was developed to compare influenza disease burdens under three different vaccination programs. Input data for the model were obtained from published literature reviews and the surveillance data by Korea Disease Control Prevention and Control Agency (KDCA). Outcome measures were influenza cases, influenza-associated complications, hospitalizations and deaths. To assess the stability of the base case results with input uncertainty, both univariate and probabilistic sensitivity analyses were performed. 결과 Analysis indicated that aQIV is more effective than QIVe, resulting in the avoidance of 35,390 influenza cases (figure 2), 1,602 influenza-associated complications, 709 influenza-associated hospitalizations, and 145 influenza-associated deaths. Compared to HD-QIV, aQIV reduces the influenza associated burden of disease by preventing 7,247 influenza cases (figure 3), 328 influenza-associated complications, 145 influ- enza-associated hospitalizations, and 30 influenza-associated deaths. Both univariate and probabilistic sensitivity analysis confirmed above findings are robust against fluctuations of input variables. The most influencing factors on outcomes were relative vaccine effectiveness and influenza incidence rates among low-risk, unvaccinated population. 결론 Switching the vaccination strategy from QIVe to aQIV is predicted to reduce the influenza-associated disease burden for the elderly in South Korea. Public health gains from aQIV and HD-QIV is expected to be comparable. Future studies comparing the effectiveness of the vaccines will further inform the future vaccination strategies for the elderly in South Korea. [ABSTRACT FROM AUTHOR]

The past decades influenza B lineages Victoria and Yamagata cocirculated. Our aim was to estimate the distribution of the two lineages circulating in Greece and any possible mismatching with vaccine influenza B strains. We studied 490 laboratory-confirmed influenza B nonsevere acute respiratory infection (non-SARI) cases diagnosed in the two National Influenza Reference Laboratories by reverse transcriptase polymerase chain reaction from July 1, 2005 to June 30, 2015 and 100 influenza B SARI cases diagnosed from July 1, 2011 to June 30, 2015. Median matching between the circulating influenza B lineages and the vaccine influenza B strains was 19.2% (range: 0–100%) for non-SARI cases during 2005–2015 and 67.6% (range: 41.2–94.1%) for SARI cases during 2011–2015. In two influenza seasons (2005–2006 and 2006–2007), complete lineage mismatch between influenza B non-SARI cases and influenza B vaccine strains was found. We estimated that 5, 12, or 16 laboratory-confirmed SARI cases could have been prevented by quadrivalent influenza inactivated vaccine (QIV) during the 2011–2012 season and 1, 2, or 3 SARI cases during the 2014–2015 season, with a vaccination coverage rate of 70% and a vaccine effectiveness of 20%, 50%, or 70%, respectively. Significant cocirculation of Victoria and Yamagata B strains and mismatching with vaccine influenza B strains were found during 2005–2015 in Greece. The wide use of a QIV instead of a TIV will confer additional immunity and therefore protection against influenza B, and it is expected to prevent several SARI cases annually. Our findings strongly support the recommendations for using QIV. [ABSTRACT FROM AUTHOR]

Now WHO experts annually formulates references on structure of both the 3rd, and 4 valent vaccines against influenza applied worldwide.The purpose of work was the assessment of averted costs due to influenza vaccination with trivalent and quadrivalent vaccines in different age groups.Material and methods. The analysis was carried out by a modeling from a societal perspective taking into account epidemiological data on the Russian Federation.Results. According to data on structure of the allocated influenza viruses in the Russian Federation for 2006-2015, at vaccination coverage of 40% of the population, replacement of trivalent vaccines with quadrivalent vaccines could prevent in addition during the season on average 604 cases of influenza per 100 thousand children aged up to 3 years, 736 cases per 100 thousand children at the age of 3–6 years, 613 cases per 100 thousand children aged from 7 up to 14 years, 106 cases per 100 thousand citizens at the age of 15– 64 years, 19 cases per 100 thousand citizens at the age of 65 years and older. In the whole population replacement of trivalent vaccines with quadrivalent vaccines would allow to prevent during the season on average 181 cases of influenza per 100 thousand citizens in addition.The averted cost is the greatest at vaccination of children of preschool and school age.In general, the volume of the costs averted when replacing trivalent vaccines with quadrivalent vaccines against influenza could be increased for 2006–2015 on average by 15,0%, and during separate seasons this increasing could be more.Replacement of a trivalent vaccines with quadrivalent vaccines could cause decrease in number of cases of influenza during the season by 265,8 thousand, and the costs averted could make 2,498 billion rubles.Conclusions. Influenza vaccination with quadrivalent vaccines can increase clinical effectiveness and costs averted in comparison with trivalent vaccines. Replacement of trivalent vaccines with quadrivalent vaccines can be the most significant at vaccination of children of preschool and school age, and also in adults from risk groups and elderly people. Economic and clinical advantages of quadrivalent vaccines in comparison with the trivalent vaccines depend on a share in the general structure of a case rate of the strains of influenza B which aren’t relating to the line included in the trivalent vaccine.

The goal of this study was to investigate the serological titers of circulating antibodies against human papillomavirus (HPV) type 16 (anti-HPV16) prior to the detection of an incident HPV16 or HPV31 infection amongst vaccinated participants. Patients were selected from a prospective post-HPV vaccine longitudinal cohort at Mount Sinai Adolescent Health Center in Manhattan, NY. We performed a nested case–control study of 43 cases with incident detection of cervical HPV16 (n = 26) or HPV31 (n = 17) DNA who had completed the full set of immunizations of the quadrivalent HPV vaccine (4vHPV). Two control individuals whom had received three doses of the vaccine (HPV16/31-negative) were selected per case, matched on age at the first dose of vaccination and follow-up time in the study: a random control, and a high-risk control that was in the upper quartile of a sexual risk behavior score. We conducted an enzyme-linked immunosorbent assay (ELISA) for the detection of immunoglobulin G (IgG) antibodies specific to anti-HPV16 virus-like particles (VLPs). The results suggest that the average log antibody titers were higher among high-risk controls than the HPV16/31 incident cases and the randomly selected controls. We show a prospective association between anti-HPV16 VLP titers and the acquisition of an HPV16/31 incident infection post-receiving three doses of 4vHPV vaccine.

This study for the first time assessed quadrivalent human papillomavirus (qHPV) vaccine effectiveness against HPV6/11/16/18-related high-grade cervical disease in Japanese women (16–26 years old), as previously demonstrated in overseas trials, and vaccine safety in a longer term (48-month) open-label study (NCT01544478). Participants received three doses of qHPV vaccine (Day 1, Month 2, Month 6). Effectiveness endpoints, assessed in the per-protocol population, included incidence of HPV6/11/16/18-related cervical intraepithelial neoplasia (CIN) Grade 2 or worse (CIN Grade 2 and 3, adenocarcinoma in situ, and/or cervical cancer) as primary endpoint and incidence of external genital lesions (EGLs). Disease related to other high-risk HPV types was also assessed. Adverse events (AEs) and serious AEs (SAEs) were collected from Days 1–15 after any vaccination; vaccine-related SAEs, deaths, and new medical conditions were collected throughout the study. A total of 1030 women received at least one vaccination. No cases of CIN2 or worse or EGLs were reported in the per-protocol population. Injection site-related AEs were reported in 14.5% of participants; most were mild and resolved within 15 days. Vaccine-related systemic AEs occurred in 8.6% of participants, most commonly headache (2.3%), malaise (1.7%), and pyrexia (1.3%). There were no vaccine-related SAEs; one participant discontinued due to a vaccine-related AE of mild uticaria. Overall, qHPV vaccine effectiveness against HPV6/11/16/18-related high-grade cervical disease and EGLs was indicated in Japanese women. The vaccine was well-tolerated, without new safety signals throughout the 48-month study period. Findings are consistent with overseas qHPV vaccine pivotal trials. clinicaltrials.gov; NCT01544478. [ABSTRACT FROM AUTHOR]

Human papilloma virus (HPV) infection is a major challenge to modern health care. At the moment there is only one way to effectively prevent diseases associated with HPV. There is vaccination. The available vaccines prevent most cases of HPVassociated diseases and can significantly reduce the financial burden of this infection. The article evaluated the economic and demographic burden of HPV-associated diseases in the Russian Federation, and also identifies the possible reduction of this burden with timely vaccination of girls by quadrivalent vaccine.

Abstract Background More deaths occur in African women from invasive cervical cancer (ICC) than from any other malignancy. ICC is caused by infection with oncogenic types of human papillomavirus (HPV). Co-infection with the human immunodeficiency virus (HIV) accelerates the natural history of ICC, and may influence the HPV type distribution. Because HPV vaccines are available, this malignancy is theoretically preventable, but the vaccines are largely type-specific in protection against infection. Data on specific HPV types causing ICC in African women is limited, and many studies utilized swab samples rather than actual cancer tissue. A previous study using archived, ICC tissue from women in Botswana identified an unusual HPV type distribution. A similar study was therefore performed in a second sub-Saharan country to provide additional information on the HPV type distribution in ICC. Methods Archived, formalin-fixed, paraffin-embedded ICCs were acquired from women in the United States, Kenya, or Botswana. DNA was extracted and HPV genotyping performed by Roche Linear Array. HIV sequences were identified in ICCs by PCR. Results HPV types 16 or 18 (HPV 16/18) were identified in 93.5 % of HPV-positive ICCs from the U.S., 93.8 % from Kenya, and 61.8 % from Botswana (p

Background: This phase 3, multi-center, open-label study evaluated the immunogenicity and safety of a quadrivalent meningococcal conjugate vaccine (MenACWY-CRM, Menveo®; Novartis Vaccines and Diagnostics S.r.l., Siena, Italy) in healthy Indian subjects aged 2–75 years, to provide data for licensure in India. Methods: A total of 180 subjects were enrolled (60 subjects 2–10 years, 60 subjects 11–18 years, and 60 subjects 19–75 years) and received one dose of MenACWY-CRM. Serum bactericidal activity with human complement (hSBA) was measured before and 1 month after vaccination. Adverse events were collected throughout the 29-day study period. Results: Percentages of subjects with post-vaccination hSBA ≥8 were 72%, 95%, 94%, and 90% for serogroups A, C, W, and Y, respectively. Geometric mean titers rose 7-fold to 42-fold against the four serogroups. Similar immune responses were observed for the age subgroups 2–10 years, 11–18 years, and 19–75 years. Seroresponse rates at 1 month following vaccination were 72%, 88%, 55%, and 71% for serogroups A, C, W, and Y, respectively. The vaccine was well tolerated with no safety concerns. Conclusion: A single dose of MenACWY-CRM induced a robust immune response against all four meningococcal serogroups and was well tolerated in an Indian population 2–75 years of age.

High prevalence of sexually transmitted diseases among the population attracts attention of specialists in all countries due to frequent development of complications resulting in reproductive dysfunction. The article presents one of the urgent issues of modern medicine — papillomavirus infection, which is the most common sexually transmitted disease. 70–80% of the sexually active persons contract human papilloma virus at one point. HPV induces a broad range of oncological reproductive diseases, including cervical, vulvar, vaginal and anal cancer and anogenital condylomae, which are observed both in men and women. The only reliable method of preventing papillomavirus infection is vaccination. The authors present new data on the use of the quadrivalent vaccine, including a new immunization pattern for 9–14-years-old girls.

Background Cervical cancer occurrence and mortality are strongly correlated with socioeconomic disadvantage, largely due to unequal access to screening and treatment. Universal human papillomavirus (HPV) vaccination provides the opportunity to greatly reduce this global health disparity. Australian Indigenous women have substantially higher rates of cervical cancer than non-Indigenous women, primarily due to under-screening. We investigated HPV infection rates in Indigenous women 7 years after implementation of the national HPV vaccination program. Methods We used a repeat cross-sectional design, with the baseline being provided by an HPV prevalence survey among Indigenous women attending clinics for cervical cytology screening, prior to the start of the vaccination program in 2007. We returned to clinics in four locations during 2014–15, and invited women aged 18–26 years attending for screening to provide a cervical specimen for HPV testing, as well as to complete a short questionnaire and consent to allow access of their records in the National HPV Vaccination Program Register. We used well-established laboratory methods to test specimens for specific HPV genotypes. Results A total of 142 women were recruited at participating sites and compared to 155 who had been recruited at the same locations in the 2007 pre-vaccine survey. The two groups were identical in regard to age, with the more recent group having a higher proportion of hormonal contraception users, and a lower proportion of smokers. The proportion found to have any HPV type fell from 58 to 36% with the decline being entirely due to reductions in vaccine types, which fell by 94% from 24 to 1.4%. Conclusion Australia’s national HPV vaccination program appears to be successfully protecting a very high proportion of Indigenous women against vaccine targeted HPV types, who have in the past been at elevated risk of cervical cancer. [ABSTRACT FROM AUTHOR]

The development of an effective preventative hepatitis C virus (HCV) vaccine will reside, in part, in its ability to elicit neutralizing antibodies (NAbs). We previously reported a genotype 1a HCV virus like particle (VLP) vaccine that produced HCV specific NAb and T cell responses that were substantially enhanced by Toll-like receptor 2 (TLR2) agonists. We have now produced a quadrivalent genotype 1a/1b/2a/3a HCV VLP vaccine and tested the ability of two TLR2 agonists, R4Pam2Cys and E8Pam2Cys, to stimulate the production of NAb. We now show that our vaccine with R4Pam2Cys or E8Pam2Cys produces strong antibody and NAb responses in vaccinated mice after just two doses. Total antibody titers were higher in mice inoculated with vaccine plus E8Pam2Cys compared to HCV VLPs alone. However, the TLR2 agonists did not result in stronger NAb responses compared to vaccine without adjuvant. Such a vaccine could provide a substantial addition to the overall goal to eliminate HCV. [ABSTRACT FROM AUTHOR]

Background In Luxembourg, a national Human Papillomavirus (HPV) vaccination programme was introduced in 2008, targeting 12–17 year old girls offering a choice of bivalent or quadrivalent vaccine free of charge. In 2015, the programme was changed offering the bivalent vaccine only to 11–13 year old girls. The aim of this study was to evaluate the HPV vaccination coverage, to assess the impact of age target changes and compare vaccination coverage to other European countries. Methods Anonymous HPV vaccination records consisting of individual vaccine doses obtained free of charge in pharmacies between 2008 and 2016 were extracted from the Luxembourgish Social Security database. Additional aggregate tables by nationality and municipality were analysed. Results Of the target cohort of 39,610 girls born between 1991 and 2003 residing in Luxembourg, 24,550 (62.0%) subjects obtained at least one dose, 22,082 (55.7%) obtained at least two doses, and 17,197 (43.4%) obtained three doses of HPV vaccine. The mean age at first dose was 13.7 years during 2008–14 and 12.7 years in 2016 after the age target change. Coverage varied significantly by nationality (p < 0.0001): Portuguese (80%), former Yugoslavs (74%), Luxembourgish (54%), Belgian (52%), German (47%), French (39%) and other nationalities (51%). Coverage varied also by geographical region, with lower rates (<50%) noted in some Northern and Central areas of Luxembourg (range: 38% to 78%). Conclusion Overall HPV vaccination coverage in Luxembourg is moderate and varied by nationality and region. The policy changes in 2015 did not have a substantial impact except lowering age at initiating vaccination. Options to improve coverage deserve further investigation. [ABSTRACT FROM AUTHOR]

Objective: To examine the epidemiological and economic impact of a nine-valent (nonavalent) human papillomavirus (HPV) 6/11/16/18/31/33/45/52/58 vaccine programme for young teenagers in Singapore.Design: Mathematical modelling.Setting: Pharmaco-economic simulation projection.Population: Singapore demography.Methods: Clinical, epidemiological and financial data from Singapore were used in a validated HPV transmission dynamic mathematical model to analyse the impact of nonavalent HPV vaccination over quadrivalent and bivalent vaccines in a school-based 2-dose vaccination for 11- to 12-year-old girls in the country. The model assumed routine cytology screening in the current rate (50%) and vaccine coverage rate of 80%.Main Outcome Measures: Changes over a 100-year time period in the incidence and mortality rates of cervical cancer, case load of genital warts, and incremental cost-effectiveness ratio (ICER).Results: Compared with bivalent and quadrivalent HPV vaccination programmes, nonavalent HPV universal vaccination resulted in an additional reduction of HPV31/33/45/52/58 related CIN1 of 40.5%, CIN 2/3 of 35.4%, cervical cancer of 23.5%, and cervical cancer mortality of 20.2%. Compared with bivalent HPV vaccination, there was an additional reduction in HPV-6/11 related CIN1 of 75.7%, and genital warts of 78.9% in women and 73.4% in men. Over the 100 years, after applying a discount of 3%, disease management cost will be reduced by 32.5% (versus bivalent) and 7.5% (versus quadrivalent). The incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year gained was SGD 929 compared with bivalent vaccination and SGD 9864 compared with quadrivalent vaccination.Conclusion: Universal two-dose nonavalent HPV vaccination for 11- to 12-year-old adolescent women is very cost-effective in Singapore.Tweetable Abstract: Nonavalent HPV vaccination of 11- to 12-year-old girls is cost-effective in Singapore. [ABSTRACT FROM AUTHOR]

Background This was an extension study of a randomized, double-blind, placebo-controlled immunogenicity and safety study of the quadrivalent human papillomavirus (qHPV) (HPV 6, 11, 16, and 18) vaccine conducted in Chinese female subjects aged 9–45 years and male subjects aged 9–15 years. To investigate the persistence of anti-HPV 6, -11, -16, and -18 responses among Chinese subjects, subjects enrolled in the base study were followed up at around month 42 (approximately 3.5 years after vaccination). Methods Among 600 subjects enrolled in the base study, a total of 468 subjects consented for participation in the extension study. Anti-HPV 6, -11, -16, and -18 antibodies were detected by the competitive Luminex immunoassay (cLIA) and total IgG Luminex immunoassay (IgG LIA). Results Among the female subjects who received the qHPV vaccine, the proportions of subjects remained seropositive were high with both the cLIA and IgG LIA for HPV type 6, 11, and 16 through approximately 42 months following the first dose vaccination. For HPV 18, the seropositivity rate remained high as 82.0% with the IgG LIA, while it decreased to 53.6% with the cLIA, which was similar to the findings observed in other studies. The seropositivity rates remained high at month 42 for all qHPV types with both the cLIA and IgG LIA among the male subjects. Conclusions Administration of a 3-dose regimen of qHPV vaccine induces durable anti-HPV 6, anti-HPV 11, anti-HPV 16, and anti-HPV 18 responses among Chinese subjects for at least 3.5 years after vaccination. ClinicalTrials.gov registry: NCT01427777 [ABSTRACT FROM AUTHOR]

Influenza virus imprinting is now understood to significantly influence the immune responses and clinical outcome of influenza virus infections that occur later in life. Due to the yearly cycling of influenza viruses, humans are imprinted with the circulating virus of their birth year and subsequently build a complex influenza virus immune history. Despite this knowledge, little is known about how the imprinting strain influences vaccine responses. To investigate the immune responses of the imprinted host to split-virion vaccination, we imprinted ferrets with a sublethal dose of the historical seasonal H1N1 strain A/USSR/90/1977. After a +60-day recovery period to build immune memory, ferrets were immunized and then challenged on Day 123. Antibody specificity and recall were investigated throughout the time course. At challenge, the imprinted vaccinated ferrets did not experience significant disease, while naïve-vaccinated ferrets had significant weight loss. Haemagglutination inhibition assays showed that imprinted ferrets had a more robust antibody response post vaccination and increased virus neutralization activity. Imprinted-vaccinated animals had increased virus-specific IgG antibodies compared to the other experimental groups, suggesting B-cell maturity and plasticity at vaccination. These results should be considered when designing the next generation of influenza vaccines.

CONTEXT: India experienced pandemic phase of H1N1 in May 2009 to December 2010. The postpandemic phase went on from January 2011 to December 2014. As per the WHO, all countries should immunize their health-care workers as a first priority to protect the essential health infrastructure. AIMS: The aim of the study is to assess the level of awareness and acceptance of influenza vaccine among physicians and also the perception of physicians regarding H1N1 infection. This study also examined time of vaccine administration in relation with efficacy concerns based on literature. SETTINGS AND DESIGN: A vaccination campaign was conducted for all health-care workers of Seth GSMC and KEM Hospital, Mumbai, in the month of July 2017 based on which a cross-sectional observational study was conducted among the physicians of the same institute. METHODS: After ethical clearance, a prevalidated pretested survey based on a pilot survey of 20 physicians was distributed among physicians, which was based on the awareness and acceptance of H1N1 vaccination among physicians and perception of H1N1 infection. Effective sample size was 272. STATISTICAL ANALYSIS USED: Descriptive statistics and Chi-square test were generated for the survey responses. All the continuous variables were reported as mean, median, and range. Categorical variables were reported as tables and pie charts. P < 0.05 was taken as significant. Data analysis was done with SPSS version 21. RESULTS: The overall vaccine compliance was 29.8%. This study has found that area of work, deficiency in knowledge about adverse effect of vaccine, misconceptions regarding vaccine, and concerns about efficacy and duration of vaccine are the important factors which lead to decreased vaccine compliance. Furthermore, it is found during the study that timing of vaccination was not given due importance as considering the epidemiological pattern. CONCLUSIONS: More emphasis should be given to education sessions and counseling of physicians regarding H1N1 vaccination and oseltamivir therapy. At administrative level, more focus should be given on timing of vaccination and other logistics. Vaccine campaigns should be conducted ideally 1 month before expected rise in cases. Quadrivalent vaccine would be more appropriate over trivalent based on epidemiology of infection in India.