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Phillips MT, Antillon M, Bilcke J, Bar-Zeev N, Limani F, Debellut F, Pecenka C, Neuzil KM, Gordon MA, Thindwa D, Paltiel AD, Yaesoubi R, Pitzer VE. Cost-effectiveness analysis of typhoid conjugate vaccines in an outbreak setting: a modeling study. BMC Infect Dis 2023; 23:143. [PMID: 36890448 PMCID: PMC9993384 DOI: 10.1186/s12879-023-08105-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 02/20/2023] [Indexed: 03/10/2023] Open
Abstract
BACKGROUND Several prolonged typhoid fever epidemics have been reported since 2010 throughout eastern and southern Africa, including Malawi, caused by multidrug-resistant Salmonella Typhi. The World Health Organization recommends the use of typhoid conjugate vaccines (TCVs) in outbreak settings; however, current data are limited on how and when TCVs might be introduced in response to outbreaks. METHODOLOGY We developed a stochastic model of typhoid transmission fitted to data from Queen Elizabeth Central Hospital in Blantyre, Malawi from January 1996 to February 2015. We used the model to evaluate the cost-effectiveness of vaccination strategies over a 10-year time horizon in three scenarios: (1) when an outbreak is likely to occur; (2) when an outbreak is unlikely to occur within the next ten years; and (3) when an outbreak has already occurred and is unlikely to occur again. We considered three vaccination strategies compared to the status quo of no vaccination: (a) preventative routine vaccination at 9 months of age; (b) preventative routine vaccination plus a catch-up campaign to 15 years of age; and (c) reactive vaccination with a catch-up campaign to age 15 (for Scenario 1). We also explored variations in outbreak definitions, delays in implementation of reactive vaccination, and the timing of preventive vaccination relative to the outbreak. RESULTS Assuming an outbreak occurs within 10 years, we estimated that the various vaccination strategies would prevent a median of 15-60% of disability-adjusted life-years (DALYs). Reactive vaccination was the preferred strategy for WTP values of $0-300 per DALY averted. For WTP values > $300, introduction of preventative routine TCV immunization with a catch-up campaign was the preferred strategy. Routine vaccination with a catch-up campaign was cost-effective for WTP values above $890 per DALY averted if no outbreak occurs and > $140 per DALY averted if implemented after the outbreak has already occurred. CONCLUSIONS Countries for which the spread of antimicrobial resistance is likely to lead to outbreaks of typhoid fever should consider TCV introduction. Reactive vaccination can be a cost-effective strategy, but only if delays in vaccine deployment are minimal; otherwise, introduction of preventive routine immunization with a catch-up campaign is the preferred strategy.
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Affiliation(s)
- Maile T Phillips
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College St., P.O. Box 208034, New Haven, CT, 06520-8034, USA
| | - Marina Antillon
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Joke Bilcke
- Center for Health Economics Research and Modeling Infectious Diseases, University of Antwerp, Antwerp, Belgium
| | - Naor Bar-Zeev
- International Vaccine Access Center, Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Malawi Liverpool Wellcome Programme, Blantyre, Malawi
| | - Fumbani Limani
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi.,Kamuzu University of Health Sciences, Blantyre, Malawi
| | | | - Clint Pecenka
- Center for Vaccine Innovation and Access, PATH, Seattle, WA, USA
| | - Kathleen M Neuzil
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Melita A Gordon
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi.,Kamuzu University of Health Sciences, Blantyre, Malawi.,Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Deus Thindwa
- Malawi Liverpool Wellcome Programme, Blantyre, Malawi.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - A David Paltiel
- Department of Health Policy, Yale School of Public Health, New Haven, CT, USA
| | - Reza Yaesoubi
- Department of Health Policy, Yale School of Public Health, New Haven, CT, USA
| | - Virginia E Pitzer
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College St., P.O. Box 208034, New Haven, CT, 06520-8034, USA.
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Getchell M, Mantaring EJ, Yee K, Pronyk P. Cost-effectiveness of sub-national geographically targeted vaccination programs: A systematic review. Vaccine 2023; 41:2320-2328. [PMID: 36781333 DOI: 10.1016/j.vaccine.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 01/19/2023] [Accepted: 02/03/2023] [Indexed: 02/13/2023]
Abstract
Immunization is an essential component of national health plans. However, the growing number of new vaccine introductions, vaccination campaigns and increasing administrative costs create logistic and financial challenges, especially in resource-limited settings. Sub-national geographic targeting of vaccination programs is a potential strategy for governments to reduce the impact of infectious disease outbreaks while optimizing resource allocation and reducing costs, promoting sustainability of critically important national immunization plans. We conducted a systematic review of peer-reviewed literature to identify studies that investigated the cost-effectiveness of geographically targeted sub-national vaccination programs, either through routine immunization or supplementary immunization activities. A total of 16 studies were included in our review, covering nine diseases of interest: cholera, dengue, enterotoxigenic Escherichia coli (ETEC), hepatitis A, Japanese encephalitis, measles, rotavirus, Shigella and typhoid fever. All studies modelled cost-effectiveness of geographically targeted vaccination. Despite the variation in study design, disease focus and country context, studies generally found that in countries where a heterogenous burden of disease exists, sub-national geographic targeting of vaccination programs in areas of high disease burden was more cost-effective than a non-targeted strategy. Sensitivity analysis revealed that cost-effectiveness was most sensitive to variations in vaccine price, vaccine efficacy, mortality rate, administrative and operational costs, discount rate, and treatment costs. This systematic review identified several key characteristics related to geographic targeting of vaccination, including the vaccination strategy used, variations in modelling parameters and their impact on cost-effectiveness. Additional research and guidance is needed to support the appropriateness and feasibility of geographically targeted vaccination and to determine what country context would make this a viable complement to routine immunization programs.
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Affiliation(s)
- Marya Getchell
- Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore.
| | | | - Kaisin Yee
- Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore
| | - Paul Pronyk
- Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore
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Prosperi C, Thangaraj J, Hasan A, Kumar M, Truelove S, Kumar V, Winter A, Bansal A, Chauhan S, Grover G, Jain A, Kulkarni R, Sharma S, Soman B, Chaaithanya I, Kharwal S, Mishra S, Salvi N, Sharma N, Sharma S, Varghese A, Sabarinathan R, Duraiswamy A, Rani D, Kanagasabai K, Lachyan A, Gawali P, Kapoor M, Chonker S, Cutts F, Sangal L, Mehendale S, Sapkal G, Gupta N, Hayford K, Moss W, Murhekar M. Added value of the measles-rubella supplementary immunization activity in reaching unvaccinated and under-vaccinated children, a cross-sectional study in five Indian districts, 2018-20. Vaccine 2023; 41:486-495. [PMID: 36481106 PMCID: PMC9831119 DOI: 10.1016/j.vaccine.2022.11.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/29/2022] [Accepted: 11/04/2022] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Supplementary immunization activities (SIAs) aim to interrupt measles transmission by reaching susceptible children, including children who have not received the recommended two routine doses of MCV before the SIA. However, both strategies may miss the same children if vaccine doses are highly correlated. How well SIAs reach children missed by routine immunization is a key metric in assessing the added value of SIAs. METHODS Children aged 9 months to younger than 5 years were enrolled in cross-sectional household serosurveys conducted in five districts in India following the 2017-2019 measles-rubella (MR) SIA. History of measles containing vaccine (MCV) through routine services or SIA was obtained from documents and verbal recall. Receipt of a first or second MCV dose during the SIA was categorized as "added value" of the SIA in reaching un- and under-vaccinated children. RESULTS A total of 1,675 children were enrolled in these post-SIA surveys. The percentage of children receiving a 1st or 2nd dose through the SIA ranged from 12.8% in Thiruvananthapuram District to 48.6% in Dibrugarh District. Although the number of zero-dose children prior to the SIA was small in most sites, the proportion reached by the SIA ranged from 45.8% in Thiruvananthapuram District to 94.9% in Dibrugarh District. Fewer than 7% of children remained measles zero-dose after the MR SIA (range: 1.1-6.4%) compared to up to 28% before the SIA (range: 7.3-28.1%). DISCUSSION We demonstrated the MR SIA provided considerable added value in terms of measles vaccination coverage, although there was variability across districts due to differences in routine and SIA coverage, and which children were reached by the SIA. Metrics evaluating the added value of an SIA can help to inform the design of vaccination strategies to better reach zero-dose or undervaccinated children.
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Affiliation(s)
- C. Prosperi
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - J.W.V. Thangaraj
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - A.Z. Hasan
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - M.S. Kumar
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - S. Truelove
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA,Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - V.S. Kumar
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - A.K. Winter
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA,Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - A.K. Bansal
- ICMR-National JALMA Institute for Leprosy & Other Mycobacterial Diseases, Agra, India
| | - S.L. Chauhan
- ICMR- National Institute for Research in Reproductive and Child Health (NIRRCH), Mumbai, India
| | - G.S. Grover
- Directorate of Health Services, Government of Punjab, Chandigarh, India
| | - A.K. Jain
- ICMR-National Institute of Pathology, New Delhi, India
| | - R.N. Kulkarni
- ICMR- National Institute for Research in Reproductive and Child Health (NIRRCH), Mumbai, India
| | - S.K. Sharma
- ICMR-Regional Medical Research Centre, NE Region, Dibrugarh, India
| | - B. Soman
- Achutha Menon Centre for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - I.K. Chaaithanya
- Department of Health Research, Model Rural Health Research Unit-Dahanu, Maharashtra, India
| | - S. Kharwal
- Department of Health Research, Model Rural Health Research Unit-Hoshiarpur, Punjab, India
| | - S.K. Mishra
- Department of Health Research, Model Rural Health Research Unit-Hoshiarpur, Punjab, India
| | - N.R. Salvi
- Department of Health Research, Model Rural Health Research Unit-Dahanu, Maharashtra, India
| | - N.P. Sharma
- Department of Health Research, Model Rural Health Research Unit-Chabua, Assam, India
| | - S. Sharma
- Department of Health Research, Model Rural Health Research Unit-Kanpur, Uttar Pradesh, India
| | - A. Varghese
- Achutha Menon Centre for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, Kerala, India
| | - R. Sabarinathan
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - A. Duraiswamy
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - D.S. Rani
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - K. Kanagasabai
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
| | - A. Lachyan
- Department of Health Research, Model Rural Health Research Unit-Dahanu, Maharashtra, India
| | - P. Gawali
- Department of Health Research, Model Rural Health Research Unit-Dahanu, Maharashtra, India
| | - M. Kapoor
- Department of Health Research, Model Rural Health Research Unit-Dahanu, Maharashtra, India
| | - S.K. Chonker
- Department of Health Research, Model Rural Health Research Unit-Kanpur, Uttar Pradesh, India
| | - F.T. Cutts
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - L. Sangal
- World Health Organization, Southeast Asia Region Office, New Delhi, India
| | - S.M. Mehendale
- PD Hinduja Hospital and Medical Research Centre, Mumbai, India
| | - G.N. Sapkal
- ICMR-National Institute of Virology, Pune, India
| | - N. Gupta
- Division of Epidemiology and Communicable Diseases, Indian Council of Medical Research, New Delhi, India
| | - K. Hayford
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - W.J. Moss
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA,Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA,Corresponding author at: International Vaccine Access Center, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
| | - M.V. Murhekar
- Indian Council of Medical Research (ICMR)-National Institute of Epidemiology, Chennai, India
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Immunogenicity after outbreak response immunization activities among young healthcare workers with secondary vaccine failure during the measles epidemic in Korea, 2019. BMC Infect Dis 2022; 22:530. [PMID: 35676650 PMCID: PMC9175155 DOI: 10.1186/s12879-022-07511-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/27/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Despite high vaccination coverage, measles outbreaks have been reported in measles elimination countries, especially among healthcare workers in their 20 and 30 s. This study was designed to identify measles-susceptible individuals and to evaluate whether primary or secondary vaccine failure occurred during measles outbreak response immunization (ORI) activities. METHODS The study population was divided into three groups as follows: natural immunity group (Group 1), vaccine-induced immunity group (Group 2), and vaccine failure group (Group 3). We evaluated the immunogenicity of measles among healthcare workers using three methods-enzyme-linked immunoassays, plaque reduction neutralization tests, and avidity assays. The results were assessed at baseline, 4 weeks after, and 6 months after the completion of measles-mumps-rubella (MMR) vaccination. RESULTS In total, 120 subjects were enrolled, with 40 subjects in each group. The median age of Group 3 was 29 years, which was significantly lower than that of the other groups. The baseline negative measles virus (MeV) IgG in Group 3 increased to a median value of 165 AU/mL at 4 weeks after ORI and was lower than that in Groups 1 and 2. The median neutralizing antibody titer was highest in Group 1, and this was significantly different from that in Group 2 or Group 3 at 4 weeks (944 vs. 405 vs. 482 mIU/mL, P = 0.001) and 6 months (826 vs. 401 vs. 470, P = 0.011) after ORI. The rates of high MeV avidity IgG were highest in Group 2, and these were significantly different from those in Groups 1 or 3 at 4 weeks (77.5 vs. 90% vs. 88.6%, P = 0.03) and 6 months (81 vs. 94.8 vs. 82.1%, P = 0.01) after ORI. CONCLUSIONS Considering the MeV-neutralizing antibodies and IgG avidity after MMR vaccination in measles-susceptible group, vaccine failure is inferred as secondary vaccine failure, and further data regarding the maintenance of immunogenicity are needed based on long-term data. The MeV-neutralizing antibody levels were highest in the natural immunity group, and the primary vaccine-induced immunity group showed the highest rates of high MeV IgG avidity.
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Buus M, da Silva I, Nielsen S, Thysen SM, Fisker AB. Coverage and factors associated with receiving campaign polio vaccines in an urban population in Guinea-Bissau. Vaccine 2021; 39:6720-6726. [PMID: 34654578 DOI: 10.1016/j.vaccine.2021.08.090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 08/13/2021] [Accepted: 08/25/2021] [Indexed: 11/26/2022]
Abstract
BACKGROUND Polio eradication campaigns are intended to complement routine immunization. Studies addressing factors associated with campaign coverage are warranted to identify children missed by campaigns. METHODS Bandim Health Project runs demographic surveillance with registration of routine immunization and campaign participation data in urban Guinea-Bissau. We assessed coverage and factors associated with receiving campaign polio vaccines in children aged 0-35 months in two polio eradication campaigns conducted in 2017 and 2018 using univariate and multivariate regression models. RESULTS Campaign coverage reached 84% in 2017 and 88% in 2018. We found lower coverage among children of young and not formally educated mothers in univariate analyses; Children <9 months and Fula children had lower campaign coverage in both univariate and multivariate analyses. CONCLUSIONS To increase campaign coverage in urban Guinea-Bissau attention may be directed at informing young mothers, mothers of young children, mothers without formal education, and the Fula ethnic group about campaigns.
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Affiliation(s)
- M Buus
- Bandim Health Project, OPEN, Department of Clinical Research, Odense University Hospital/University of Southern Denmark, Denmark; Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau; Department of Public Health, Aarhus University, Aarhus, Denmark
| | - I da Silva
- Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau
| | - S Nielsen
- Bandim Health Project, OPEN, Department of Clinical Research, Odense University Hospital/University of Southern Denmark, Denmark; Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau
| | - S M Thysen
- Bandim Health Project, OPEN, Department of Clinical Research, Odense University Hospital/University of Southern Denmark, Denmark; Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau
| | - A B Fisker
- Bandim Health Project, OPEN, Department of Clinical Research, Odense University Hospital/University of Southern Denmark, Denmark; Bandim Health Project, INDEPTH Network, Bissau, Guinea-Bissau.
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Coulborn RM, Nackers F, Bachy C, Porten K, Vochten H, Ndele E, Van Herp M, Bibala-Faray E, Cohuet S, Panunzi I. Field challenges to measles elimination in the Democratic Republic of the Congo. Vaccine 2020; 38:2800-2807. [PMID: 32111528 DOI: 10.1016/j.vaccine.2020.02.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/06/2020] [Accepted: 02/07/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND During a measles epidemic, the Ministry of Public Health (MOH) of the Democratic Republic of the Congo conducted supplementary immunization activities (2016-SIA) from August 28-September 3, 2016 throughout Maniema Province. From October 29-November 4, 2016, Médecins Sans Frontières and the MOH conducted a reactive measles vaccination campaign (2016-RVC) targeting children six months to 14 years old in seven health areas with heavy ongoing transmission despite inclusion in the 2016-SIA, and a post-vaccination survey. We report the measles vaccine coverage (VC) and effectiveness (VE) of the 2016-SIA and VC of the 2016-RVC. METHODS A cross-sectional VC cluster survey stratified by semi-urban/rural health area and age was conducted. A retrospective cohort analysis of measles reported by the parent/guardian allowed calculation of the cumulative measles incidence according to vaccination status after the 2016-SIA for an estimation of crude and adjusted VE. RESULTS In November 2016, 1145 children (6-59 months old) in the semi-urban and 1158 in the rural areas were surveyed. Post-2016-SIA VC (documentation/declaration) was 81.6% (95%CI: 76.5-85.7) in the semi-urban and 91.0% (95%CI: 84.9-94.7) in the rural areas. The reported measles incidence in October among children less than 5 years old was 5.0% for 2016-SIA-vaccinated and 11.2% for 2016-SIA-non-vaccinated in the semi-urban area, and 0.7% for 2016-SIA-vaccinated and 4.0% for 2016-SIA-non-vaccinated in the rural area. Post-2016-SIA VE (adjusted for age, sex) was 53.9% (95%CI: 2.9-78.8) in the semi-urban and 78.7% (95%CI: 0-97.1) in the rural areas. Post 2016-RVC VC (documentation/declaration) was 99.1% (95%CI: 98.2-99.6) in the semi-urban and 98.8% (95%CI: 96.5-99.6) in the rural areas. CONCLUSIONS Although our VE estimates could be underestimated due to misclassification of measles status, the VC and VE point estimates of the 2016-SIA in the semi-urban area appear suboptimal, and in combination, could not limit the epidemic. Further research is needed on vaccination strategies adapted to urban contexts.
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Affiliation(s)
| | | | - C Bachy
- Médecins Sans Frontières, Brussels, Belgium
| | | | - H Vochten
- Médecins Sans Frontières, Kinshasa, Democratic Republic of the Congo
| | - E Ndele
- Médecins Sans Frontières, Kinshasa, Democratic Republic of the Congo
| | - M Van Herp
- Médecins Sans Frontières, Brussels, Belgium
| | - E Bibala-Faray
- Ministry of Public Health, Maniema, Democratic Republic of the Congo
| | | | - I Panunzi
- Médecins Sans Frontières, Brussels, Belgium
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Cutts FT, Dansereau E, Ferrari MJ, Hanson M, McCarthy KA, Metcalf CJE, Takahashi S, Tatem AJ, Thakkar N, Truelove S, Utazi E, Wesolowski A, Winter AK. Using models to shape measles control and elimination strategies in low- and middle-income countries: A review of recent applications. Vaccine 2020; 38:979-992. [PMID: 31787412 PMCID: PMC6996156 DOI: 10.1016/j.vaccine.2019.11.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 11/07/2019] [Accepted: 11/08/2019] [Indexed: 01/30/2023]
Abstract
After many decades of vaccination, measles epidemiology varies greatly between and within countries. National immunization programs are therefore encouraged to conduct regular situation analyses and to leverage models to adapt interventions to local needs. Here, we review applications of models to develop locally tailored interventions to support control and elimination efforts. In general, statistical and semi-mechanistic transmission models can be used to synthesize information from vaccination coverage, measles incidence, demographic, and/or serological data, offering a means to estimate the spatial and age-specific distribution of measles susceptibility. These estimates complete the picture provided by vaccination coverage alone, by accounting for natural immunity. Dynamic transmission models can then be used to evaluate the relative impact of candidate interventions for measles control and elimination and the expected future epidemiology. In most countries, models predict substantial numbers of susceptible individuals outside the age range of routine vaccination, which affects outbreak risk and necessitates additional intervention to achieve elimination. More effective use of models to inform both vaccination program planning and evaluation requires the development of training to enhance broader understanding of models and where feasible, building capacity for modelling in-country, pipelines for rapid evaluation of model predictions using surveillance data, and clear protocols for incorporating model results into decision-making.
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Affiliation(s)
- F T Cutts
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK.
| | - E Dansereau
- Vaccine Delivery, Global Development, The Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - M J Ferrari
- Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, USA
| | - M Hanson
- Vaccine Delivery, Global Development, The Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - K A McCarthy
- Institute for Disease Modeling, 3150 139th Ave SE, Bellevue, WA 98005, USA
| | - C J E Metcalf
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - S Takahashi
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA; Department of Medicine, University of California San Francisco, San Francisco, CA 94143, USA
| | - A J Tatem
- WorldPop, Department of Geography and Environmental Science, University of Southampton, Highfield, Southampton SO17 1BJ, UK
| | - N Thakkar
- Institute for Disease Modeling, 3150 139th Ave SE, Bellevue, WA 98005, USA
| | - S Truelove
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - E Utazi
- WorldPop, Department of Geography and Environmental Science, University of Southampton, Highfield, Southampton SO17 1BJ, UK
| | - A Wesolowski
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - A K Winter
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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Hagedorn BL, Dabbagh A, McCarthy KA. The cost saving opportunity of introducing a card review into measles-containing vaccination campaigns. Vaccine 2019; 37:6093-6101. [PMID: 31471145 DOI: 10.1016/j.vaccine.2019.08.049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 08/12/2019] [Accepted: 08/13/2019] [Indexed: 10/26/2022]
Abstract
Measles vaccination is a cost-effective way to prevent infection and reduce mortality and morbidity. However, in countries with fragile routine immunization infrastructure, coverage rates are still low and supplementary immunization campaigns (SIAs) are used to reach previously unvaccinated children. During campaigns, vaccine is generally administered to every child, regardless of their vaccination status and as a result, there is the possibility that a child that is already immune to measles (i.e. who has had 2+ vaccinations) would receive an unnecessary dose, resulting in excess cost. Selective vaccination has been proposed as one solution to this; children who were able to provide documentation of previous vaccination would not be vaccinated repeatedly. While this would result in reduced vaccine and supply cost, it would also require additional staff time and increased social mobilization investment, potentially outweighing the benefits. We utilize Monte Carlo simulation to assess under what conditions a selective vaccination policy would indeed result in net savings. We demonstrate that cost savings are possible in contexts with a high joint probability of an individual child having both 2+ previous measles doses and also an available record. We also find that the magnitude of net cost savings is highly dependent on whether a country is using measles-only or measles-rubella vaccine and on the required skill set of the individual who would review the previous vaccination records.
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Affiliation(s)
| | - Alya Dabbagh
- Department of Immunization, Vaccines, and Biologicals, World Health Organization, Avenue Appia 20, 1211 Genève, Switzerland
| | - Kevin A McCarthy
- Institute for Disease Modeling, 3150 139th Ave SE, Bellevue, WA 98005, USA
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Fonnesbeck CJ, Shea K, Carran S, Cassio de Moraes J, Gregory C, Goodson JL, Ferrari MJ. Measles outbreak response decision-making under uncertainty: a retrospective analysis. J R Soc Interface 2019; 15:rsif.2017.0575. [PMID: 29563241 DOI: 10.1098/rsif.2017.0575] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 02/26/2018] [Indexed: 10/17/2022] Open
Abstract
Resurgent outbreaks of vaccine-preventable diseases that have previously been controlled or eliminated have been observed in many settings. Reactive vaccination campaigns may successfully control outbreaks but must necessarily be implemented in the face of considerable uncertainty. Real-time surveillance may provide critical information about at-risk population and optimal vaccination targets, but may itself be limited by the specificity of disease confirmation. We propose an integrated modelling approach that synthesizes historical demographic and vaccination data with real-time outbreak surveillance via a dynamic transmission model and an age-specific disease confirmation model. We apply this framework to data from the 1996-1997 measles outbreak in São Paulo, Brazil. To simulate the information available to decision-makers, we truncated the surveillance data to what would have been available at 1 or 2 months prior to the realized interventions. We use the model, fitted to real-time observations, to evaluate the likelihood that candidate age-targeted interventions could control the outbreak. Using only data available prior to the interventions, we estimate that a significant excess of susceptible adults would prevent child-targeted campaigns from controlling the outbreak and that failing to account for age-specific confirmation rates would underestimate the importance of adult-targeted vaccination.
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Affiliation(s)
- Christopher J Fonnesbeck
- Department of Biostatistics, Vanderbilt University Medical Center, Eleventh Floor, Suite 11000, 2525 West End Avenue, Nashville, TN, USA
| | - Katriona Shea
- Department of Biology and Intercollege Graduate Degree Program in Ecology, 208 Mueller Laboratory, The Pennsylvania State University, University Park, PA, USA.,Center for Infectious Disease Dynamics, Department of Biology, Eberly College of Science, The Pennsylvania State University, University Park, PA, USA
| | - Spencer Carran
- Center for Infectious Disease Dynamics, Department of Biology, Eberly College of Science, The Pennsylvania State University, University Park, PA, USA
| | | | - Christopher Gregory
- Arboviral Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, US Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - James L Goodson
- Accelerated Disease Control and Vaccine Preventable Disease Surveillance Branch, Global Immunization Division, Center for Global Health, US Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Matthew J Ferrari
- Department of Biology and Intercollege Graduate Degree Program in Ecology, 208 Mueller Laboratory, The Pennsylvania State University, University Park, PA, USA.,Center for Infectious Disease Dynamics, Department of Biology, Eberly College of Science, The Pennsylvania State University, University Park, PA, USA
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10
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Gastañaduy PA, Banerjee E, DeBolt C, Bravo-Alcántara P, Samad SA, Pastor D, Rota PA, Patel M, Crowcroft NS, Durrheim DN. Public health responses during measles outbreaks in elimination settings: Strategies and challenges. Hum Vaccin Immunother 2018; 14:2222-2238. [PMID: 29932850 PMCID: PMC6207419 DOI: 10.1080/21645515.2018.1474310] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 04/19/2018] [Accepted: 05/03/2018] [Indexed: 02/08/2023] Open
Abstract
In late September 2016, the Americas became the first region in the world to have eliminated endemic transmission of measles virus. Several other countries have also verified measles elimination, and countries in all six World Health Organization regions have adopted measles elimination goals. The public health strategies used to respond to measles outbreaks in elimination settings are thus becoming relevant to more countries. This review highlights the strategies used to limit measles spread in elimination settings: (1) assembly of an outbreak control committee; (2) isolation of measles cases while infectious; (3) exclusion and quarantining of individuals without evidence of immunity; (4) vaccination of susceptible individuals; (5) use of immunoglobulin to prevent measles in exposed susceptible high-risk persons; (6) and maintaining laboratory proficiency for confirmation of measles. Deciding on the extent of containment efforts should be based on the expected benefit of reactive interventions, balanced against the logistical challenges in implementing them.
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Affiliation(s)
- Paul A. Gastañaduy
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Emily Banerjee
- Vaccine Preventable Disease Surveillance Unit, Minnesota Department of Health, St. Paul, MN, USA
| | - Chas DeBolt
- Vaccine-Preventable Diseases, Washington State Department of Health, Shoreline, WA, USA
| | - Pamela Bravo-Alcántara
- Comprehensive Family Immunization Unit, Pan American Health Organization, Washington, DC, USA
| | | | - Desiree Pastor
- Comprehensive Family Immunization Unit, Pan American Health Organization, Washington, DC, USA
| | - Paul A. Rota
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Manisha Patel
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Natasha S. Crowcroft
- Public Health Ontario, Toronto, ON, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
| | - David N. Durrheim
- School of Medicine and Public Health, University of Newcastle, Newcastle, New South Wales, Australia
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11
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Abstract
Measles eradication efforts have been successful at achieving elimination in many countries worldwide. Such countries actively work to maintain this elimination by continuing to improve coverage of two routine doses of measles vaccine following measles elimination. While improving measles vaccine coverage is always beneficial, we show, using a steady-state analysis of a dynamical model, that the correlation between populations receiving the first and second routine dose also has a significant impact on the population immunity achieved by a specified combination of first and second dose coverage. If the second dose is administered to people independently of whether they had the first dose, high second-dose coverage improves the proportion of the population receiving at least one dose, and will have a large effect on population immunity. If the second dose is administered only to people who have had the first dose, high second-dose coverage reduces the rate of primary vaccine failure, but does not reach people who missed the first dose; this will therefore have a relatively small effect on population immunity. When doses are administered dependently, and assuming the first dose has higher coverage, increasing the coverage of the first dose has a larger impact on population immunity than does increasing the coverage of the second. Correlation between vaccine doses has a significant impact on the level of population immunity maintained by current vaccination coverage, potentially outweighing the effects of age structure and, in some cases, recent improvements in vaccine coverage. It is therefore important to understand the correlation between vaccine doses as such correlation may have a large impact on the effectiveness of measles vaccination strategies.
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12
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Impact of measles supplementary immunization activities on reaching children missed by routine programs. Vaccine 2017; 36:170-178. [PMID: 29174680 DOI: 10.1016/j.vaccine.2017.10.080] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 09/25/2017] [Accepted: 10/26/2017] [Indexed: 11/23/2022]
Abstract
BACKGROUND Measles supplementary immunization activities (SIAs) are vaccination campaigns that supplement routine vaccination programs with a recommended second dose opportunity to children of different ages regardless of their previous history of measles vaccination. They are conducted every 2-4 years and over a few weeks in many low- and middle-income countries. While SIAs have high vaccination coverage, it is unclear whether they reach the children who miss their routine measles vaccine dose. Determining who is reached by SIAs is vital to understanding their effectiveness, as well as measure progress towards measles control. METHODS We examined SIAs in low- and middle-income countries from 2000 to 2014 using data from the Demographic and Health Surveys. Conditional on a child's routine measles vaccination status, we examined whether children participated in the most recent measles SIA. RESULTS The average proportion of zero-dose children (no previous routine measles vaccination defined as no vaccination date before the SIA) reached by SIAs across 14 countries was 66%, ranging from 28% in São Tomé and Príncipe to 91% in Nigeria. However, when also including all children with routine measles vaccination data, this proportion decreased to 12% and to 58% when imputing data for children with vaccination reported by the mother and vaccination marks on the vaccination card across countries. Overall, the proportions of zero-dose children reached by SIAs declined with increasing household wealth. CONCLUSIONS Some countries appeared to reach a higher proportion of zero-dose children using SIAs than others, with proportions reached varying according to the definition of measles vaccination (e.g., vaccination dates on the vaccination card, vaccination marks on the vaccination card, and/or self-reported data). This suggests that some countries could improve their targeting of SIAs to children who miss other measles vaccine opportunities. Across all countries, SIAs played an important role in reaching children from poor households.
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13
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Sokol R, Fisher E, Hill J. Identifying Those Whom Health Promotion Hardly Reaches: A Systematic Review. Eval Health Prof 2015; 38:518-37. [PMID: 26405265 DOI: 10.1177/0163278715605883] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
To understand what circumstances lend groups to be recognized as hardly reached by health services and research, we systematically reviewed studies that identified their priority populations as hard to reach. We classified attributes of hardly reached groups into cultural/environmental, individual, and demographic domains. Of the 334 identified studies, 78.74% used attributes that were classified into the cultural/environmental, 74.85% the individual, and 50% the demographic domain to identify those hardly reached. Of all possible combinations of domains, the most common was the use of all three domains (28.74%). Overall, papers were more likely to use attributes to identify their hardly reached population that fell into more than one domain (74.85%) compared to only one domain (25.15%; χ(2), p < .0001). Through this review, we identified the attributes of those who have been identified as hardly reached in published research. No single attribute is used to identify those who are hardly reached. This reflects a socioecological perspective, emphasizing that both intrapersonal and external elements may cause interventions to fail to reach those intended. Moreover, the focus not on populations hardly reached but on the attributes of those hardly reached suggests objectives for interventions to reach them better.
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Affiliation(s)
- Rebeccah Sokol
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Edwin Fisher
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Julia Hill
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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14
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Gil Cuesta J, Mukembe N, Valentiner-Branth P, Stefanoff P, Lenglet A. Measles vaccination coverage survey in moba, katanga, democratic republic of congo, 2013: need to adapt routine and mass vaccination campaigns to reach the unreached. PLOS CURRENTS 2015; 7:ecurrents.outbreaks.8a1b00760dfd81481eb42234bd18ced3. [PMID: 25713744 PMCID: PMC4336195 DOI: 10.1371/currents.outbreaks.8a1b00760dfd81481eb42234bd18ced3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Democratic Republic of Congo (DRC) has committed to eliminate measles by 2020. In 2013, in response to a large outbreak, Médecins Sans Frontières conducted a mass vaccination campaign (MVC) in Moba, Katanga, DRC. We estimated the measles vaccination coverage for the MVC, the Expanded Programme on Immunization routine measles vaccination (EPI) and assessed reasons for non-vaccination. We conducted a household-based survey among caretakers of children aged 6 months-15 years in Moba from November to December 2013. We used a two-stage-cluster-sampling, where clusters were allocated proportionally to village size and households were randomly selected from each cluster. The questionnaire included demographic variables, vaccination status (card or oral history) during MVC and EPI and reasons for non-vaccination. We estimated the coverage by gender, age and the reasons for non-vaccination and calculated 95% confidence intervals (95% CI). We recruited 4,768 children living in 1,684 households. The MVC coverage by vaccination card and oral history was 87% (95% CI 84-90) and 66% (95% CI 61-70) if documented by card. The EPI coverage was 76% (95% CI 72-81) and 3% (95% CI 1-4) respectively. The MVC coverage was significantly higher among children previously vaccinated during EPI 91% (95% CI 88-93), compared to 74% (95% CI 66-80) among those not previously vaccinated. Six percent (n=317) of children were never vaccinated. The main reason for non-vaccination was family absence 68% (95% CI 58-78). The MVC and EPI measles coverage was insufficient to prevent the recurrence of outbreaks in Moba. Lack of EPI vaccination and lack of accessibility by road were associated with lower MVC coverage. We recommend intensified social mobilization and extended EPI and MVCs to increase the coverage of absent residents and unreached children. Routine and MVCs need to be adapted accordingly to improve coverage in hard-to-reach populations in DRC.
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Affiliation(s)
- Julita Gil Cuesta
- Infectious Disease Epidemiology, Statens Serum Institute, European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Copenhager, Denmark
| | - Narcisse Mukembe
- Médecins Sans Frontières, Operational Center Amsterdam, Lubumbashi, Democratic Republic of Congo
| | | | - Pawel Stefanoff
- Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
| | - Annick Lenglet
- Public Health Department, Médecins Sans Frontières, Operational Center Amsterdam, Amsterdam, The Netherlands
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15
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Troeger C, Sack DA, Chao DL. Evaluation of targeted mass cholera vaccination strategies in Bangladesh: a demonstration of a new cost-effectiveness calculator. Am J Trop Med Hyg 2014; 91:1181-1189. [PMID: 25294614 PMCID: PMC4257645 DOI: 10.4269/ajtmh.14-0159] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Growing interest in mass vaccination with oral cholera vaccine in endemic and epidemic settings will require policymakers to evaluate how to allocate these vaccines in the most efficient manner. Because cholera, when treated properly, has a low case fatality rate, it may not be economically feasible to vaccinate an entire population. Using a new publicly available calculator for estimating the cost-effectiveness of mass vaccination, we show how targeting high-risk subpopulations for vaccination could be cost-effective in Bangladesh. The approach described here is general enough to adapt to different settings or to other vaccine-preventable diseases.
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Affiliation(s)
| | | | - Dennis L. Chao
- *Address correspondence to Dennis L. Chao, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, Seattle, WA 98109. E-mail:
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16
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Mancini S, Coldiron ME, Ronsse A, Ilunga BK, Porten K, Grais RF. Description of a large measles epidemic in Democratic Republic of Congo, 2010-2013. Confl Health 2014; 8:9. [PMID: 25053974 PMCID: PMC4105555 DOI: 10.1186/1752-1505-8-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 06/24/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although measles mortality has declined dramatically in Sub-Saharan Africa, measles remains a major public health problem in countries like the Democratic Republic of Congo (DRC). Here, we describe the large measles epidemic that occurred in the Democratic Republic of Congo between 2010 and 2013 using data from the national surveillance system as well as vaccine coverage surveys to provide a snapshot of the epidemiology of measles in DRC. METHODS Standardized national surveillance data were used to describe measles cases from 2010 to 2013. Attack rates and case fatality ratios were calculated and the temporal and spatial evolution of the epidemic described. Data on laboratory confirmation and vaccination coverage surveys as a part of routine program monitoring are also presented. FINDINGS Between week 1 of 2010 and week 45 of 2013, a total of 294,455 cases and 5,045 deaths were reported. The cumulative attack rate (AR) was 0.4%. The Case Fatality Ratio (CFR) was 1.7% among cases reported in health structures through national surveillance. A total of 186,178 cases (63%) were under 5 years old, representing an estimated AR of 1.4% in this age group. Following the first mass vaccination campaigns, weekly reported cases decreased by 21.5%. Results of post-vaccination campaign coverage surveys indicated sub-optimal (under 95%) vaccination coverage among children surveyed. CONCLUSIONS The data reported here highlight the need to seek additional means to reinforce routine immunization as well as ensure the timely implementation of Supplementary Immunization Activities to prevent large and repeated measles epidemics in DRC. Although reactive campaigns were conducted in response to the epidemic, strategies to ensure that children are vaccinated in the routine system remains the foundation of measles control.
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Affiliation(s)
- Silvia Mancini
- Epicentre, 8 Rue Saint Sabin, Paris 75011, France
- Médecins Sans Frontières, Via Magenta 5, Rome, Italy
| | | | | | - Benoît Kebela Ilunga
- Ministry of Health, Av. De la Justice 39, Gombe I, Kinshasa, Democratic Republic of Congo
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