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Winter AK, Takahashi S, Carcelen AC, Hayford K, Mutale W, Mwansa FD, Sinyange N, Ngula D, Moss WJ, Mutembo S. An evaluation of the early impact of the COVID-19 pandemic on Zambia's routine immunization program. PLOS Glob Public Health 2023; 3:e0000554. [PMID: 37130089 PMCID: PMC10153718 DOI: 10.1371/journal.pgph.0000554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 03/31/2023] [Indexed: 05/03/2023]
Abstract
Implications of the COVID-19 pandemic for both populations and healthcare systems are vast. In addition to morbidity and mortality from COVID-19, the pandemic also disrupted local health systems, including reductions or delays in routine vaccination services and catch-up vaccination campaigns. These disruptions could lead to outbreaks of other infectious diseases that result in an additional burden of disease and strain on the healthcare system. We evaluated the impact of the COVID-19 pandemic on Zambia's routine childhood immunization program in 2020 using multiple sources of data. We relied on administrative vaccination data and Zambia's 2018 Demographic and Health Survey to project national disruptions to district-specific routine childhood vaccination coverage within the pandemic year 2020. Next, we leveraged a 2016 population-based serological survey to predict age-specific measles seroprevalence and assessed the impact of changes in vaccination coverage on measles outbreak risk in each district. We found minor disruptions to routine administration of measles-rubella and pentavalent vaccines in 2020. This was in part due to Zambia's Child Health Week held in June of 2020 which helped to reach children missed during the first six months of the year. We estimated that the two-month delay in a measles-rubella vaccination campaign, originally planned for September of 2020 but conducted in November of 2020 as a result of the pandemic, had little impact on modeled district-specific measles outbreak risks. This study estimated minimal increases in the number of children missed by vaccination services in Zambia during 2020. However, the ongoing SARS-CoV-2 transmission since our analysis concluded means efforts to maintain routine immunization services and minimize the risk of measles outbreaks will continue to be critical. The methodological framework developed in this analysis relied on routinely collected data to estimate disruptions of the COVID-19 pandemic to national routine vaccination program performance and its impact on children missed at the subnational level can be deployed in other countries or for other vaccines.
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Affiliation(s)
- Amy K Winter
- Department of Epidemiology and Biostatistics, University of Georgia, Athens, Georgia, United States of America
| | - Saki Takahashi
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Andrea C Carcelen
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Kyla Hayford
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Wilbroad Mutale
- School of Public Health, University of Zambia, Lusaka, Zambia
| | - Francis D Mwansa
- Child Health Unit, Directorate of Public Health and Research, Ministry of Health, Lusaka, Zambia
| | - Nyambe Sinyange
- Field Epidemiology Training Program, Zambia National Public Health Institute, Lusaka, Zambia
| | - David Ngula
- Child Health Unit, Directorate of Public Health and Research, Ministry of Health, Lusaka, Zambia
| | - William J Moss
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Simon Mutembo
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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Carcelen AC, Prosperi C, Mutembo S, Chongwe G, Mwansa FD, Ndubani P, Simulundu E, Chilumba I, Musukwa G, Thuma P, Kapungu K, Hamahuwa M, Mutale I, Winter A, Moss WJ, Truelove SA. COVID-19 vaccine hesitancy in Zambia: a glimpse at the possible challenges ahead for COVID-19 vaccination rollout in sub-Saharan Africa. Hum Vaccin Immunother 2021; 18:1-6. [PMID: 34227914 PMCID: PMC8920139 DOI: 10.1080/21645515.2021.1948784] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
With unprecedented speed, multiple vaccines against SARS-CoV-2 are available 1 year after the COVID-19 pandemic was first identified. As we push to achieve global control through these new vaccines, old challenges present themselves, including cold-chain storage, the logistics of mass vaccination, and vaccine hesitancy. Understanding how much hesitancy toward COVID-19 vaccines might occur and what factors may be driving these concerns can improve the ability of public health workers and communicators to maximize vaccine uptake. We nested a survey within a measles-rubella mass vaccination campaign in Zambia in November 2020 and asked about sentiments and beliefs toward COVID-19 and COVID-19 vaccines. Among parents bringing their children to receive a measles-rubella vaccine, we found high acceptability of COVID-19 vaccination of their children, but substantial uncertainty and hesitancy about receiving the vaccine themselves. COVID-19 vaccination hesitancy was correlated with beliefs around COVID-19 severity and risk, as well as vaccine safety and effectiveness.
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Affiliation(s)
- Andrea C Carcelen
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Christine Prosperi
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Simon Mutembo
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,Laboratory Science, Macha Research Trust, Choma, Zambia
| | - Gershom Chongwe
- Department of Immunology, Tropical Diseases Research Center, Ndola, Zambia
| | - Francis D Mwansa
- Ministry of the Health, Government of the Republic of Zambia, Lusaka, Zambia
| | | | | | - Innocent Chilumba
- Department of Immunology, Tropical Diseases Research Center, Ndola, Zambia
| | | | - Phil Thuma
- Laboratory Science, Macha Research Trust, Choma, Zambia
| | - Kelvin Kapungu
- Department of Immunology, Tropical Diseases Research Center, Ndola, Zambia
| | | | - Irene Mutale
- Department of Immunology, Tropical Diseases Research Center, Ndola, Zambia
| | - Amy Winter
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - William J Moss
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,W Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Shaun A Truelove
- Department of International Health, International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.,Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Carcelen AC, Mutembo S, Matakala KH, Chilumba I, Mulundu G, Monze M, Mwansa FD, Moss WJ, Hayford K. Impact of a Measles and Rubella Vaccination Campaign on Seroprevalence in Southern Province, Zambia. Am J Trop Med Hyg 2021; 104:2229-2232. [PMID: 33939639 PMCID: PMC8176503 DOI: 10.4269/ajtmh.20-1669] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 03/05/2021] [Indexed: 11/07/2022] Open
Abstract
Zambia conducted a measles and rubella (MR) vaccination campaign targeting children 9 months to younger than 15 years of age in 2016. This campaign was the first introduction of a rubella-containing vaccine in Zambia. To evaluate the impact of the campaign, we compared the MR seroprevalence estimates from serosurveys conducted before and after the campaign in Southern Province, Zambia. The measles seroprevalence increased from 77.8% (95% confidence interval [CI], 73.2-81.9) to 96.4% (95% CI, 91.7-98.5) among children younger than 15 years. The rubella seroprevalence increased from 51.3% (95% CI, 45.6-57.0) to 98.3% (95% CI, 95.5-99.4). After the campaign, slightly lower seroprevalence remained for young adults 15 to 19 years old, who were not included in the campaign because of their age. These serosurveys highlighted the significant impact of the vaccination campaign and identified immunity gaps for those beyond the targeted vaccination age. Continued monitoring of population immunity can signal the need for future targeted vaccination strategies.
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Affiliation(s)
- Andrea C Carcelen
- 1Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Simon Mutembo
- 1Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,2Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia
| | | | | | - Gina Mulundu
- 5University of Zambia School of Medicine, Lusaka, Zambia.,6University Teaching Hospital, Lusaka, Zambia
| | - Mwaka Monze
- 5University of Zambia School of Medicine, Lusaka, Zambia
| | - Francis D Mwansa
- 2Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia
| | - William J Moss
- 1Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,7Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Kyla Hayford
- 1Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
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Carcelen AC, Hayford K, Moss WJ, Book C, Thuma PE, Mwansa FD, Patenaude B. How much does it cost to measure immunity? A costing analysis of a measles and rubella serosurvey in southern Zambia. PLoS One 2020; 15:e0240734. [PMID: 33057405 PMCID: PMC7561102 DOI: 10.1371/journal.pone.0240734] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 10/01/2020] [Indexed: 12/03/2022] Open
Abstract
Background Serosurveys are a valuable surveillance tool because they provide a more direct measure of population immunity to infectious diseases, such as measles and rubella, than vaccination coverage estimates. However, there is concern that serological surveys are costly. We adapted a framework to capture the costs associated with conducting a serosurvey in Zambia. Methods We costed a nested serosurvey in Southern Province, Zambia that collected dried blood spots from household residents in a post-campaign vaccine coverage survey. The financial costs were estimated using an ingredients-based costing approach. Inputs included personnel, transportation, field consumable items, social mobilization, laboratory supplies, and capital items, and were classified by serosurvey function (survey preparation, data collection, biospecimen collection, laboratory testing, and coordination). Inputs were stratified by whether they were applicable to surveys in general or attributable specifically to serosurveys. Finally, we calculated the average cost per cluster and participant. Results We estimated the total nested serosurvey cost was US $68,558 to collect dried blood spots from 658 participants in one province in Zambia. A breakdown of the cost by serosurvey phase showed data collection accounted for almost one third of the total serosurvey cost (32%), followed by survey preparation (25%) and biospecimen collection (20%). Analysis by input categories indicated personnel costs were the largest contributing input to overall serosurvey costs (51%), transportation was second (23%), and field consumables were third (9%). By combining the serosurvey with a vaccination coverage survey, there was a savings of $43,957. We estimated it cost $4,285 per average cluster and $104 per average participant sampled. Conclusions Adding serological specimen collection to a planned vaccination coverage survey provided a more direct measurement of population immunity among a wide age group but increased the cost by approximately one-third. Future serosurveys could consider ways to leverage existing surveys conducted for other purposes to minimize costs.
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Affiliation(s)
- Andrea C. Carcelen
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
| | - Kyla Hayford
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - William J. Moss
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | | | | | | | - Bryan Patenaude
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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Feldhaus I, Schütte C, Mwansa FD, Undi M, Banda S, Suharlim C, Menzies NA, Brenzel L, Resch SC, Kinghorn A. Incorporating costing study results into district and service planning to enhance immunization programme performance: a Zambian case study. Health Policy Plan 2019; 34:327-336. [PMID: 31157376 PMCID: PMC6736183 DOI: 10.1093/heapol/czz039] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2019] [Indexed: 11/13/2022] Open
Abstract
Donors, researchers and international agencies have made significant investments in collection of high-quality data on immunization costs, aiming to improve the efficiency and sustainability of services. However, improved quality and routine dissemination of costing information to local managers may not lead to enhanced programme performance. This study explored how district- and service-level managers can use costing information to enhance planning and management to increase immunization outputs and coverage. Data on the use of costing information in the planning and management of Zambia's immunization programme was obtained through individual and group semi-structured interviews with planners and managers at national, provincial and district levels. Document review revealed the organizational context within which managers operated. Qualitative results described managers' ability to use costing information to generate cost and efficiency indicators not provided by existing systems. These, in turn, would allow them to understand the relative cost of vaccines and other resources, increase awareness of resource use and management, benchmark against other facilities and districts, and modify strategies to improve performance. Managers indicated that costing information highlighted priorities for more efficient use of human resources, vaccines and outreach for immunization programming. Despite decentralization, there were limitations on managers' decision-making to improve programme efficiency in practice: major resource allocation decisions were made centrally and planning tools did not focus on vaccine costs. Unreliable budgets and disbursements also undermined managers' ability to use systems and information. Routine generation and use of immunization cost information may have limited impact on managing efficiency in many Zambian districts, but opportunities were evident for using existing capacity and systems to improve efficiency. Simpler approaches, such as improving reliability and use of routine immunization and staffing indicators, drawing on general insights from periodic costing studies, and focusing on maximizing coverage with available resources, may be more feasible in the short-term.
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Affiliation(s)
- Isabelle Feldhaus
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Carl Schütte
- Strategic Development Consultants, Pietermaritzburg, South Africa
| | - Francis D Mwansa
- Department of Public Health, Ministry of Health, Plot 12193, Woodlands Chalala, Lusaka, Zambia
| | - Masauso Undi
- Independent consultant, 35 Nalikwanda Road, Woodlands, Lusaka, Zambia
| | - Stanley Banda
- Independent consultant, Plot 34270, Shantumbu Road, Hillview Park, Lusaka, Zambia
| | - Chris Suharlim
- Center for Health Decision Science, Harvard T.H. Chan School of Public Health, 718 Huntington Ave, Boston, MA, USA
| | - Nicolas A Menzies
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Center for Health Decision Science, Harvard T.H. Chan School of Public Health, 718 Huntington Ave, Boston, MA, USA
| | - Logan Brenzel
- Bill & Melinda Gates Foundation, 500 Fifth Avenue N, Seattle, WA, USA
| | - Stephen C Resch
- Center for Health Decision Science, Harvard T.H. Chan School of Public Health, 718 Huntington Ave, Boston, MA, USA
| | - Anthony Kinghorn
- Perinatal HIV Research Unit, Chris Hani Baragwanath Academic Hospital, Chris Hani Road, Diepkloof, Soweto, South Africa
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Hayford K, Mutembo S, Carcelen A, Matakala HK, Munachoonga P, Winter A, Wanyiri JW, Searle K, Mwansa FD, Mwiche A, Phiri C, Book C, Thuma PE, Moss WJ. Measles and rubella serosurvey identifies rubella immunity gap in young adults of childbearing age in Zambia: The added value of nesting a serological survey within a post-campaign coverage evaluation survey. Vaccine 2019; 37:2387-2393. [PMID: 30905529 PMCID: PMC6467544 DOI: 10.1016/j.vaccine.2019.02.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/19/2019] [Accepted: 02/20/2019] [Indexed: 11/13/2022]
Abstract
We nested a measles and rubella serological survey in a vaccination coverage survey. Measles and rubella immunity was significantly higher than expected by vaccination. Study revealed immunity gap in young adults and risk of congenital rubella syndrome. Adding serology to a survey leveraged resources and provided complementary information.
Background Serological surveys can potentially complement vaccine coverage surveys, such as post-vaccination campaign coverage evaluation surveys (PCES), by providing direct information on population immunity within and outside the target age range of the mass vaccination campaign. We estimate age-specific population immunity to measles and rubella viruses in Southern Province, Zambia, and assess the value of adding serological data to vaccination coverage estimates by nesting a serological survey within a PCES. Methods Dried blood spots (DBS) from fingerprick blood were collected from all individuals ages nine months or older in households participating in the PCES and tested for measles and rubella virus-specific immunoglobulin G (IgG) by enzyme immunoassay (Siemens Enzygnost, Marburg, Germany). Results Overall seroprevalence was 95.5% (95% CI: 92.8, 97.2) for measles virus-specific IgG and 97.7% (95% CI: 96.0, 98.7) for rubella virus-specific IgG. Rubella seroprevalence was 98.4% (95% CI: 95.9, 99.4) among children eligible for the MR vaccination campaign, significantly higher than the reported measles-rubella (MR) vaccination campaign coverage of 89.8% (p = 0.003), and higher than the 91.3% rubella seroprevalence for adolescents and adults 16–30 years of age (p = 0.049). Conclusion Seroprevalence to measles and rubella viruses in children younger than 16 years of age was significantly higher than expected from vaccination coverage estimates, likely reflecting exposure to wild-type viruses and underreporting of vaccination. The serosurvey revealed rubella immunity gaps among women 16–30 years of age, precisely the age group in which protection from rubella is most important to prevent congenital rubella syndrome. Nesting serological surveys within existing surveys can leverage resources and infrastructure while providing complementary information important to immunization programs.
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Affiliation(s)
- Kyla Hayford
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Simon Mutembo
- Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia; Department of Epidemiology and Biostatistics, University of Georgia, College of Public Health, Athens, GA, USA
| | - Andrea Carcelen
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | | | | | - Amy Winter
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Jane W Wanyiri
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Kelly Searle
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Francis D Mwansa
- Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia
| | - Angels Mwiche
- Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia
| | - Caroline Phiri
- Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia
| | | | | | - William J Moss
- 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
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Mutembo S, Carcelen A, Mwansa FD, Searle K, Wanyiri JW, Book C, Thuma PE, Moss WJ, Hayford K. Integrating Blood Collection within Household Surveys: Lessons Learned from Nesting a Measles and Rubella Serological Survey within a Post-Campaign Coverage Evaluation Survey in Southern Province, Zambia. Am J Trop Med Hyg 2018; 99:1639-1642. [PMID: 30277204 PMCID: PMC6283518 DOI: 10.4269/ajtmh.18-0320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Age-specific population immunity to many vaccine-preventable diseases can be measured using serological surveys. However, stand-alone serological surveys are infrequently conducted in low- and middle-income countries because of costs, operational challenges, and potential high refusal rates for blood collection. Nesting a serosurvey within a household cluster survey may overcome some of these challenges. We share lessons learned from nesting a serosurvey within a measles and rubella vaccination post-campaign coverage evaluation survey (PCES). In 15 of the 26 PCES clusters in Southern Province, Zambia, we collected dried blood spots from 581 participants aged 9 months and older. Household participation rates for the main PCES were higher in the serosurvey clusters (86%) than PCES-only clusters (71%), suggesting that a serosurvey can be successfully integrated without adversely affecting PCES participation. Among households that participated in the PCES, 80% also participated in the serosurvey and 86% of individuals available in the household provided a blood sample for the serosurvey. Substantial planning and coordination, additional staff training, and community mobilization were critical to the success of the serosurvey. Most challenges stemmed from using different data collecting tools and teams for the serosurvey and PCES. A more efficient design would be to fully integrate the serosurvey by adding blood collection and additional questions to the PCES.
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Affiliation(s)
- Simon Mutembo
- Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia.,Department of Epidemiology and Biostatistics, University of Georgia, College of Public Health, Athens, Georgia
| | - Andrea Carcelen
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Francis D Mwansa
- Ministry of Health, Government of the Republic of Zambia, Lusaka, Zambia
| | - Kelly Searle
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Jane W Wanyiri
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | | | - William J Moss
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.,International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Kyla Hayford
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
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