1
|
Gurav YK, Bagepally BS, Chitpim N, Sobhonslidsuk A, Gupte MD, Chaikledkaew U, Thakkinstian A, Thavorncharoensap M. Cost-effective analysis of hepatitis A vaccination in Kerala state, India. PLoS One 2024; 19:e0306293. [PMID: 38935781 PMCID: PMC11210869 DOI: 10.1371/journal.pone.0306293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 06/14/2024] [Indexed: 06/29/2024] Open
Abstract
Several hepatitis A outbreaks have recently been reported in Kerala state, India. To inform coverage decision of hepatitis A vaccine in Kerala, this study aimed to examine the cost-effectiveness of 1) hepatitis A vaccination among children aged 1 year and individuals aged 15 years, and 2) serological screening of individuals aged 15 years and vaccination of susceptible as compared to no vaccination or vaccination without serological screening. Both live attenuated hepatitis A vaccine and inactivated hepatitis A vaccine were considered in the analysis. A combination of decision tree and Markov models with a cycle length of one year was employed to estimate costs and benefits of different vaccination strategies. Analysis were based on both societal and payer perspectives. The lifetime costs and outcomes were discounted by 3%. Our findings indicated that all strategies were cost-saving for both societal and payer perspectives. Moreover, budget impact analysis revealed that vaccination without screening among individuals aged 15 years could save the government's budget by reducing treatment cost of hepatitis A. Our cost-effectiveness evidence supports the inclusion of hepatitis A vaccination into the vaccination program for children aged 1 year and individuals aged 15 years in Kerala state, India.
Collapse
Affiliation(s)
- Yogesh Krishnarao Gurav
- Mahidol University Health Technology Assessment (MUHTA) Graduate Program, Mahidol University, Bangkok, Thailand
- Health Technology Assessment Group, ICMR-National Institute of Virology, Pune, Maharashtra, India
| | - Bhavani Shankara Bagepally
- Mahidol University Health Technology Assessment (MUHTA) Graduate Program, Mahidol University, Bangkok, Thailand
- Division of Non-Communicable Diseases, ICMR-National Institute of Epidemiology, Chennai, Tamil Nadu, India
| | - Natthakan Chitpim
- Social, Economic and Administrative Pharmacy Graduate Program, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Abhasnee Sobhonslidsuk
- Division of Gastroenterology and Hepatology, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | | | - Usa Chaikledkaew
- Mahidol University Health Technology Assessment (MUHTA) Graduate Program, Mahidol University, Bangkok, Thailand
- Social and Administrative Pharmacy Division, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Ammarin Thakkinstian
- Mahidol University Health Technology Assessment (MUHTA) Graduate Program, Mahidol University, Bangkok, Thailand
- Department of Clinical Epidemiology and Biostatistics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Montarat Thavorncharoensap
- Mahidol University Health Technology Assessment (MUHTA) Graduate Program, Mahidol University, Bangkok, Thailand
- Social and Administrative Pharmacy Division, Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| |
Collapse
|
2
|
Patterson J, Cleary S, Norman JM, Van Zyl H, Awine T, Mayet S, Kagina B, Muloiwa R, Hussey G, Silal SP. Modelling the Cost-Effectiveness of Hepatitis A in South Africa. Vaccines (Basel) 2024; 12:116. [PMID: 38400100 PMCID: PMC10893480 DOI: 10.3390/vaccines12020116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/14/2024] [Accepted: 01/22/2024] [Indexed: 02/25/2024] Open
Abstract
The World Health Organization (WHO) recommends the consideration of introducing routine hepatitis A vaccination into national immunization schedules for children ≥ 1 years old in countries with intermediate HAV endemicity. Recent data suggest that South Africa is transitioning from high to intermediate HAV endemicity, thus it is important to consider the impact and cost of potential routine hepatitis A vaccination strategies in the country. An age-structured compartmental model of hepatitis A transmission was calibrated with available data from South Africa, incorporating direct costs of hepatitis A treatment and vaccination. We used the calibrated model to evaluate the impact and costs of several childhood hepatitis A vaccination scenarios from 2023 to 2030. We assessed how each scenario impacted the burden of hepatitis A (symptomatic hepatitis A cases and mortality) as well as calculated the incremental cost per DALY averted as compared to the South African cost-effectiveness threshold. All costs and outcomes were discounted at 5%. For the modelled scenarios, the median estimated cost of the different vaccination strategies ranged from USD 1.71 billion to USD 2.85 billion over the period of 2023 to 2030, with the cost increasing for each successive scenario and approximately 39-52% of costs being due to vaccination. Scenario 1, which represented the administration of one dose of the hepatitis A vaccine in children < 2 years old, requires approximately 5.3 million vaccine doses over 2023-2030 and is projected to avert a total of 136,042 symptomatic cases [IQR: 88,842-221,483] and 31,106 [IQR: 22,975-36,742] deaths due to hepatitis A over the period of 2023 to 2030. The model projects that Scenario 1 would avert 8741 DALYs over the period of 2023 to 2030; however, it is not cost-effective against the South African cost-effectiveness threshold with an ICER per DALY averted of USD 21,006. While Scenario 3 and 4 included the administration of more vaccine doses and averted more symptomatic cases of hepatitis A, these scenarios were absolutely dominated owing to the population being infected before vaccination through the mass campaigns at older ages. The model was highly sensitive to variation of access to liver transplant in South Africa. When increasing the access to liver transplant to 100% for the baseline and Scenario 1, the ICER for Scenario 1 becomes cost-effective against the CET (ICER = USD 2425). Given these findings, we recommend further research is conducted to understand the access to liver transplants in South Africa and better estimate the cost of liver transplant care for hepatitis A patients. The modelling presented in this paper has been used to develop a user-friendly application for vaccine policy makers to further interrogate the model outcomes and consider the costs and benefits of introducing routine hepatitis A vaccination in South Africa.
Collapse
Affiliation(s)
- Jenna Patterson
- Vaccines for Africa Initiative, School of Public Health, University of Cape Town, Cape Town 7925, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Susan Cleary
- School of Public Health, University of Cape Town, Cape Town 7925, South Africa
| | - Jared Michael Norman
- Modelling and Simulation Hub, Africa (MASHA), Department of Statistical Sciences, University of Cape Town, Cape Town 7700, South Africa
| | - Heiletjé Van Zyl
- Modelling and Simulation Hub, Africa (MASHA), Department of Statistical Sciences, University of Cape Town, Cape Town 7700, South Africa
| | - Timothy Awine
- Modelling and Simulation Hub, Africa (MASHA), Department of Statistical Sciences, University of Cape Town, Cape Town 7700, South Africa
| | - Saadiyah Mayet
- Modelling and Simulation Hub, Africa (MASHA), Department of Statistical Sciences, University of Cape Town, Cape Town 7700, South Africa
| | - Benjamin Kagina
- Vaccines for Africa Initiative, School of Public Health, University of Cape Town, Cape Town 7925, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Rudzani Muloiwa
- Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town 7700, South Africa
| | - Gregory Hussey
- Vaccines for Africa Initiative, School of Public Health, University of Cape Town, Cape Town 7925, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Sheetal Prakash Silal
- Modelling and Simulation Hub, Africa (MASHA), Department of Statistical Sciences, University of Cape Town, Cape Town 7700, South Africa
- Centre for Global Health, Nuffield Department of Medicine, Oxford University, Oxford OX3 7LG, UK
| |
Collapse
|
3
|
Van Damme P, Pintó RM, Feng Z, Cui F, Gentile A, Shouval D. Hepatitis A virus infection. Nat Rev Dis Primers 2023; 9:51. [PMID: 37770459 DOI: 10.1038/s41572-023-00461-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/23/2023] [Indexed: 09/30/2023]
Abstract
Hepatitis A is a vaccine-preventable infection caused by the hepatitis A virus (HAV). Over 150 million new infections of hepatitis A occur annually. HAV causes an acute inflammatory reaction in the liver that usually resolves spontaneously without chronic sequelae. However, up to 20% of patients experience a prolonged or relapsed course and <1% experience acute liver failure. Host factors, such as immunological status, age, pregnancy and underlying hepatic diseases, can affect the severity of disease. Anti-HAV IgG antibodies produced in response to HAV infection persist for life and protect against re-infection; vaccine-induced antibodies against hepatitis A confer long-term protection. The WHO recommends vaccination for individuals at higher risk of infection and/or severe disease in countries with very low and low hepatitis A virus endemicity, and universal childhood vaccination in intermediate endemicity countries. To date, >25 countries worldwide have implemented such programmes, resulting in a reduction in the incidence of HAV infection. Improving hygiene and sanitation, rapid identification of outbreaks and fast and accurate intervention in outbreak control are essential to reducing HAV transmission.
Collapse
Affiliation(s)
- Pierre Van Damme
- Centre for the Evaluation of Vaccination, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
| | - Rosa M Pintó
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Zongdi Feng
- Centre for Vaccines and Immunity, The Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Fuqiang Cui
- Department of Laboratorial Science and Technology & Vaccine Research Center, School of Public Health, Peking University, Beijing, People's Republic of China
| | - Angela Gentile
- Department of Epidemiology, Hospital de Niños Ricardo Gutierrez, University of Buenos Aires, Buenos Aires, Argentina
| | - Daniel Shouval
- Institute of Hepatology, Hadassah-Hebrew University Hospital, Jerusalem, Israel
| |
Collapse
|
4
|
Andrade AA, Paiva AD, Machado ABF. Microbiology of street food: understanding risks to improve safety. J Appl Microbiol 2023; 134:lxad167. [PMID: 37516449 DOI: 10.1093/jambio/lxad167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/26/2023] [Accepted: 07/28/2023] [Indexed: 07/31/2023]
Abstract
Street foods play important socioeconomic and cultural roles and are popular worldwide. In addition to providing convenient and low-cost meals for urban populations, street food offers an essential source of income for vendors, especially women, and it can reflect traditional local culture, which is an important attraction for tourists. Despite these benefits, the microbiological safety of street food has become a worldwide concern because it is often prepared and sold under inadequate safety conditions, without legal control and sanitary surveillance. Consequently, high counts of fecal indicator bacteria and several foodborne pathogens have been detected in street foods. This review provides insight into the microbiology of street food, focus on the associated microbiological safety aspects and main pathogens, and the global status of this important economic activity. Furthermore, the need to apply molecular detection rather than traditional culture-based methods is discussed to better understand the actual risks of microbial infection associated with street foods. Recognition is always the first step toward addressing a problem.
Collapse
Affiliation(s)
- Anderson Assunção Andrade
- Microbiology Research Laboratory, Institute of Biological and Natural Sciences, Federal University of Triângulo Mineiro (UFTM), Uberaba, Minas Gerais 38025-015, Brazil
| | - Aline Dias Paiva
- Microbiology Research Laboratory, Institute of Biological and Natural Sciences, Federal University of Triângulo Mineiro (UFTM), Uberaba, Minas Gerais 38025-015, Brazil
| | - Alessandra Barbosa Ferreira Machado
- Laboratory of Bacterial Physiology and Molecular Genetics, Center for Studies in Microbiology, Department of Parasitology, Microbiology and Immunology, Federal University of Juiz de Fora (UFJF), Juiz de Fora 36036-330, Brazil
| |
Collapse
|
5
|
Shenoy B, Andani A, Kolhapure S, Agrawal A, Mazumdar J. Endemicity change of hepatitis A infection necessitates vaccination in food handlers: An Indian perspective. Hum Vaccin Immunother 2021; 18:1868820. [PMID: 33595412 PMCID: PMC8920195 DOI: 10.1080/21645515.2020.1868820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
In the last two decades, outbreaks due to the foodborne hepatitis A virus (HAV) have been frequently reported in India, with adolescents and adults primarily affected. In India, most food handlers are adolescents and young adults who might be exposed to unsatisfactory environmental conditions and poor water quality. This increases the risk of HAV infection and consequently compounds the risk of HAV transmission from food handlers to susceptible populations. Given the shift in hepatitis A endemicity from high to intermediate levels in India, implementing the vaccination of food handlers has become important as it can also contribute to the elimination of hepatitis A in India. This narrative review makes a case for hepatitis A immunization of food handlers in India considering the growing food industry, evolving food culture, and the substantial burden caused by hepatitis A outbreaks.
What is the context?
Hepatitis A disease is a common form of viral hepatitis and is transmitted through contaminated food and water or through close contact with an infected person. The virus with stands high temperature and can survive on surfaces for long periods of time. In India, the burden of hepatitis A has shifted from children to adolescents and adults who are more culnerable to infection. They present a high risk of complications, often requiring hopitalization. The prevention of the disease has often bee neglected, inadequate safety measures for the preparation of food (via food handlers) is a known risk factor for the transmission of hepatitis A.
What is new?
Our review highlights the relationship between food handling and hepatitis A infection among adolescents and adults in Inida. The lack of knowledge of food safety regulations and hygiene measures among food handlers and the organizations that guide them may contribute to the spread of hepatitis A.
What is the impact?
Sanitation efforts, awareness and educational programs for food are needed to help reduce the transmission of hepatitis A virus and disease, yet these measures alone may not be sufficient. Vaccination among high-risk populations such as food handlers can prevent hepatitis A infection and its complications as well as transmission.
Collapse
Affiliation(s)
- Bhaskar Shenoy
- Department of Paediatrics, Division of Pediatric Infectious Diseases, Manipal Hospital, Bangalore, India
| | | | | | | | | |
Collapse
|
6
|
Andani A, van Elten TM, Bunge EM, Marano C, Salgado F, Jacobsen KH. Hepatitis A epidemiology in Latin American countries: a 2020 view from a systematic literature review. Expert Rev Vaccines 2020; 19:795-805. [PMID: 32955965 DOI: 10.1080/14760584.2020.1813575] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION The World Health Organization recommends vaccination against hepatitis A virus (HAV) for children aged 1 year and older in areas where endemicity has shifted from high to intermediate. There are no recent comprehensive reviews of the epidemiology of HAV infection in Latin America, but seroprevalence and socioeconomic data suggest that, with improved clean water and sanitation systems, countries are transitioning to intermediate endemicity. AREAS COVERED We conducted a systematic literature review of the epidemiology of HAV infection in 25 countries in the Latin American region, which included gray literature. We compiled data on HAV incidence and prevalence, including the identification of epidemiological changes observed in countries that established pediatric HAV vaccination programs. EXPERT OPINION We identified 59 relevant articles, including 34 peer-reviewed seroprevalence studies (12 recent studies from Brazil), three incidence studies, and six vaccine impact studies (three from Argentina). Based on the estimated age at midpoint of population immunity in each country, most have a high-intermediate, intermediate, or low-intermediate level of HAV endemicity, suggesting that national childhood immunization may be an appropriate disease prevention strategy. However, recent data were lacking for most countries. Improved data quality and continued epidemiological surveillance are required for this region.
Collapse
Affiliation(s)
| | - Tessa M van Elten
- Pallas Health Research and Consultancy B.V ., Rotterdam, The Netherlands
| | - Eveline M Bunge
- Pallas Health Research and Consultancy B.V ., Rotterdam, The Netherlands
| | | | | | - Kathryn H Jacobsen
- Department of Global & Community Health, George Mason University , Fairfax, VA, USA
| |
Collapse
|
7
|
Sood V, Lal BB, Gupta E, Khanna R, Siloliya MK, Alam S. Hepatitis A Virus-related Pediatric Liver Disease Burden and its Significance in the Indian Subcontinent. Indian Pediatr 2019. [DOI: 10.1007/s13312-019-1640-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
8
|
Is Time Ripe for Hepatitis A Mass Vaccination? Indian Pediatr 2019. [DOI: 10.1007/s13312-019-1630-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
9
|
Bravo C, Mege L, Vigne C, Thollot Y. Clinical experience with the inactivated hepatitis A vaccine, Avaxim 80U Pediatric. Expert Rev Vaccines 2019; 18:209-223. [PMID: 30806110 DOI: 10.1080/14760584.2019.1580578] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Hepatitis A, caused by hepatitis A virus (HAV), is primarily transmitted via the fecal/oral route either through ingestion of contaminated food and water or through direct contact with an infectious person. Prevalence of hepatitis A is strongly correlated with socioeconomic factors, decreasing with increased socio-economic development, access to clean water and sanitation. Vaccination against HAV should be part of a comprehensive plan for the prevention and control of viral hepatitis, either as part of regular childhood immunization programs or with other recommended vaccines for travelers. Areas covered: We present here evidence for the immunogenicity and safety of an inactivated HAV pediatric vaccine (Avaxim® 80U Pediatric, Sanofi Pasteur), indicated for use in children aged 12 months to 15 years. Data evaluated are from trials undertaken during the clinical development of this vaccine, a systematic literature review and post-market pharmacovigilance. Expert opinion: The pediatric HAV vaccine is highly immunogenic and generates long-lasting protection against hepatitis A disease in children. The safety and immunogenicity data presented in this review suggest that the pediatric HAV vaccine is a valuable option in the prevention of HAV infection in children in many areas of the world where the disease remains a healthcare issue.
Collapse
Affiliation(s)
| | - Larissa Mege
- b Global Pharmacovigilance , Sanofi Pasteur , Marcy-l'Étoile , France
| | - Claire Vigne
- c Research & Development , Sanofi Pasteur , Marcy-l'Étoile , France
| | - Yael Thollot
- a Global Medical Affairs , Sanofi Pasteur , Lyon , France
| |
Collapse
|
10
|
Abstract
Increased economic interdependence, social integration, and other aspects of globalization are contributing to significant changes in hepatitis A epidemiology. Globally, the incidence of hepatitis A virus (HAV) infection is decreasing, the age at midpoint of population immunity (AMPI) is increasing, and the proportion of symptomatic cases is increasing as the average age at infection increases. In low-income countries, HAV remains endemic but improved water and sanitation systems are reducing transmission rates among young children. In high-income countries, most adults remain susceptible to HAV and foodborne outbreaks are becoming more frequent. Middle-income countries have diverse epidemiological profiles, and they play important roles in the global spread of HAV through international trade and travel. Future changes in the epidemiology of hepatitis A will be heavily influenced by globalization processes.
Collapse
Affiliation(s)
- Kathryn H Jacobsen
- College of Health and Human Services, George Mason University, Fairfax, Virginia 22030
| |
Collapse
|
11
|
Drolet M, Bénard É, Jit M, Hutubessy R, Brisson M. Model Comparisons of the Effectiveness and Cost-Effectiveness of Vaccination: A Systematic Review of the Literature. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2018; 21:1250-1258. [PMID: 30314627 DOI: 10.1016/j.jval.2018.03.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/20/2018] [Accepted: 03/25/2018] [Indexed: 05/21/2023]
Abstract
OBJECTIVES To describe all published articles that have conducted comparisons of model-based effectiveness and cost-effectiveness results in the field of vaccination. Specific objectives were to 1) describe the methodologies used and 2) identify the strengths and limitations of the studies. METHODS We systematically searched MEDLINE and Embase databases for studies that compared predictions of effectiveness and cost-effectiveness of vaccination of two or more mathematical models. We categorized studies into two groups on the basis of their data source for comparison (previously published results or new simulation results) and performed a qualitative synthesis of study conclusions. RESULTS We identified 115 eligible articles (only 5% generated new simulations from the reviewed models) examining the effectiveness and cost-effectiveness of vaccination against 14 pathogens (69% of studies examined human papillomavirus, influenza, and/or pneumococcal vaccines). The goal of most of studies was to summarize evidence for vaccination policy decisions, and cost-effectiveness was the most frequent outcome examined. Only 33%, 25%, and 3% of studies followed a systematic approach to identify eligible studies, assessed the quality of studies, and performed a quantitative synthesis of results, respectively. A greater proportion of model comparisons using published studies followed a systematic approach to identify eligible studies and to assess their quality, whereas more studies using new simulations performed quantitative synthesis of results and identified drivers of model conclusions. Most comparative modeling studies concluded that vaccination was cost-effective. CONCLUSIONS Given the variability in methods used to conduct/report comparative modeling studies, guidelines are required to enhance their quality and transparency and to provide better tools for decision making.
Collapse
Affiliation(s)
- Mélanie Drolet
- Centre de recherche du CHU de Québec-Université Laval, Axe santé des populations et pratiques optimales en santé, Québec, Canada
| | - Élodie Bénard
- Centre de recherche du CHU de Québec-Université Laval, Axe santé des populations et pratiques optimales en santé, Québec, Canada
| | - Mark Jit
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK; Modelling and Economics Unit, Public Health England, London, UK
| | | | - Marc Brisson
- Centre de recherche du CHU de Québec-Université Laval, Axe santé des populations et pratiques optimales en santé, Québec, Canada; Université Laval, Québec, Canada; Department of Infectious Disease Epidemiology, Imperial College, London, UK.
| |
Collapse
|
12
|
Curran D, de Ridder M, Van Effelterre T. The impact of assumptions regarding vaccine-induced immunity on the public health and cost-effectiveness of hepatitis A vaccination: Is one dose sufficient? Hum Vaccin Immunother 2016; 12:2765-2771. [PMID: 27428611 PMCID: PMC5137541 DOI: 10.1080/21645515.2016.1203495] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 06/01/2016] [Accepted: 06/15/2016] [Indexed: 11/26/2022] Open
Abstract
Hepatitis A vaccination stimulates memory cells to produce an anamnestic response. In this study, we used a mathematical model to examine how long-term immune memory might convey additional protection against clinical/icteric infections. Dynamic and decision models were used to estimate the expected number of cases, and the costs and quality-adjusted life-years (QALYs), respectively. Several scenarios were explored by assuming: (1) varying duration of vaccine-induced immune memory, (2) and/or varying levels of vaccine-induced immune memory protection (IMP), (3) and/or varying levels of infectiousness in vaccinated individuals with IMP. The base case analysis assumed a time horizon of 25 y (2012 - 2036), with additional analyses over 50 and 75 y. The analyses were conducted in the Mexican public health system perspective. In the base case that assumed no vaccine-induced IMP, the 2-dose hepatitis A vaccination strategy was cost-effective compared with the 1-dose strategy over the 3 time horizons. However, it was not cost-effective if we assumed additional IMP durations of at least 10 y in the 25-y horizon. In the 50- and 75-y horizons, the 2-dose strategy was always cost-effective, except when 100% reduction in the probability of icteric Infections, 75% reduction in infectiousness, and mean durations of IMP of at least 50 y were assumed. This analysis indicates that routine vaccination of toddlers against hepatitis A virus would be cost-effective in Mexico using a single-dose vaccination strategy. However, the cost-effectiveness of a second dose depends on the assumptions of additional protection by IMP and the time horizon over which the analysis is performed.
Collapse
|
13
|
Declining Trend of Hepatitis A Seroepidemiology in Association with Improved Public Health and Economic Status of Thailand. PLoS One 2016; 11:e0151304. [PMID: 27008531 PMCID: PMC4805277 DOI: 10.1371/journal.pone.0151304] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 02/25/2016] [Indexed: 02/07/2023] Open
Abstract
Hepatitis A virus (HAV) is transmitted via the fecal-oral route from contaminated food or water. As part of the most recent survey of viral hepatitis burden in Thailand, we analyzed the current seroprevalence of HAV in the country and compared with data dating back to 1971. From March to October, 2014, a total of 4,260 individuals between one month and 71 years of age from different geographical regions (North = 961; Central = 1,125; Northeast = 1,109; South = 1,065) were screened for anti-HAV IgG antibody using an automated chemiluminescent microparticle immunoassay. Overall, 34.53% (1,471/4,260) possessed anti-HAV IgG antibody, and the age-standardized seroprevalence was 48.6%. Seroprevalence rates were 27.3% (North), 30.8% (Central), 33.8% (Northeast) and 45.8% (South) and were markedly lower than in the past studies especially among younger age groups. The overall trend showed an increase in the age by which 50% of the population were anti-HAV IgG antibody: 4.48 years (1971–1972), 6 (1976), 12.49 (1990), 36.02 (2004) and 42.03 (2014).This suggests that Thailand is transitioning from low to very low HAV endemicity. Lower prevalence of HAV correlated with improved healthcare system as measured by decreased infant mortality rate and improved national economy based on increased GDP per capita. The aging HAV immuno-naïve population may be rendered susceptible to potential HAV outbreaks similar to those in industrialized countries and may benefit from targeted vaccination of high-risk groups.
Collapse
|
14
|
Abstract
PURPOSE OF REVIEW Transmission of hepatitis A virus (HAV) infection is primarily fecal-oral. Symptomatic hepatitis, severe disease, and death are more likely to occur when infection occurs at an older age. Improvements in socioeconomic and hygienic conditions have led to a change in its epidemiology worldwide. RECENT FINDINGS In the last two decades, improved hygiene in several resource-poor countries has led to reduced transmission of HAV, an increase in average age at infection, and, consequently, a paradoxical increase in morbidity and mortality because of hepatitis A. In Argentina, introduction of one dose (instead of the conventional two doses, to reduce costs) of inactivated HAV vaccine at 12-month age in a universal childhood immunization program during such 'epidemiologic transition' has markedly reduced the incidence of symptomatic hepatitis A, and of fulminant hepatitis and liver transplantation caused by HAV infection. The monetary value of medical and nonmedical benefits of this strategy outweighed the expenditure on vaccination. These excellent results were possibly contingent upon a high vaccination coverage. SUMMARY Resource-poor countries should closely monitor the epidemiology of HAV infection and periodically undertake cost-effectiveness analyses of HAV immunization strategies. This should allow timely identification of epidemiologic transition and introduction of preventive strategies before HAV infection becomes a public health problem.
Collapse
|
15
|
Suwantika AA, Beutels P, Postma MJ. Cost-effectiveness of hepatitis A vaccination in Indonesia. Hum Vaccin Immunother 2015; 10:2342-9. [PMID: 25424941 DOI: 10.4161/hv.29353] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
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-dose schedule. The vaccine price, mortality rate and discount rate were the most influential parameters impacting the ICERs.
Collapse
Affiliation(s)
- Auliya A Suwantika
- a Unit of PharmacoEpidemiology&PharmacoEconomics (PE2); Department of Pharmacy; University of Groningen; Groningen, The Netherlands
| | | | | |
Collapse
|