TY - JOUR
T1 - Seasonal gaps in measles vaccination coverage in Madagascar
AU - Mensah, K.
AU - Heraud, J. M.
AU - Takahashi, S.
AU - Winter, A. K.
AU - Metcalf, C. J.E.
AU - Wesolowski, A.
N1 - Funding Information:
CJEM, AKW and ST were supported by BMGF Grant # OPP1094793. CJEM, KM, APW were funded by Wellcome Trust Sustaining Health Grant (106866/Z/15/Z). APW is supported by a Career Award at the Scientific Interface from the Burroughs Wellcome Fund and by the National Library of Medicine of the National Institutes of Health under Award Number Dp2LM013102. The content is solely the responsibility of APW and does not necessarily represent the official views of the National Institutes of Health. We would like to thank Lieehar Andriamanalina, all the healthcare workers who participated to the study, Claude Kouadio, individuals from the Immunization program in Madagascar, the Metcalf Lab and individuals from the Virology Unit and the National Reference Laboratory for Measles at the Institut Pasteur de Madagascar in particular Richter Razafindratsimandresy and Soa Fy Andriamandimby.
Funding Information:
CJEM, AKW and ST were supported by BMGF Grant # OPP1094793. CJEM, KM, APW were funded by Wellcome Trust Sustaining Health Grant (106866/Z/15/Z). APW is supported by a Career Award at the Scientific Interface from the Burroughs Wellcome Fund and by the National Library of Medicine of the National Institutes of Health under Award Number Dp2LM013102. The content is solely the responsibility of APW and does not necessarily represent the official views of the National Institutes of Health. We would like to thank Lieehar Andriamanalina, all the healthcare workers who participated to the study, Claude Kouadio, individuals from the Immunization program in Madagascar, the Metcalf Lab and individuals from the Virology Unit and the National Reference Laboratory for Measles at the Institut Pasteur de Madagascar in particular Richter Razafindratsimandresy and Soa Fy Andriamandimby.
Publisher Copyright:
© 2019 The Author(s)
PY - 2019/4/24
Y1 - 2019/4/24
N2 - Introduction: Measles elimination depends on the successful deployment of measles containing vaccine. Vaccination programs often depend on a combination of routine and non-routine services, including supplementary immunization activities (SIAs) and vaccination weeks (VWs), that both aim to vaccinate all eligible children regardless of vaccination history or natural infection. Madagascar has used a combination of these activities to improve measles coverage. However, ongoing massive measles outbreak suggests that the country was in a “honeymoon” period and that coverage achieved needs to be re-evaluated. Although healthcare access is expected to vary seasonally in low resources settings, little evidence exists to quantify temporal fluctuations in routine vaccination, and interactions with other immunization activities. Methods: We used three data sources: national administrative data on measles vaccine delivery from 2013 to 2016, digitized vaccination cards from 49 health centers in 6 health districts, and a survey of health workers. Data were analyzed using linear regressions, analysis of variance, and t-tests. Findings: From 2013 to 2016, the footprint of SIAs and VWs is apparent, with more doses distributed during the relevant timeframes. Routine vaccination decreases in subsequent months, suggesting that additional activities may be interfering with routine services. The majority of missed vaccination opportunities occur during the rainy season. Health facility organization and shortage of vaccine contributed to vaccination gaps. Children born in June were the least likely to be vaccinated on time. Discussion: Evidence that routine vaccination coverage varies over the year and is diminished by other activities suggests that maintaining routine vaccination during SIAs and VWs is a key direction for strengthening immunization programs, ensuring population immunity and avoiding future outbreaks. Funding: Wellcome Trust Fund, Burroughs Wellcome Fund, Gates Foundation, National Institutes of Health.
AB - Introduction: Measles elimination depends on the successful deployment of measles containing vaccine. Vaccination programs often depend on a combination of routine and non-routine services, including supplementary immunization activities (SIAs) and vaccination weeks (VWs), that both aim to vaccinate all eligible children regardless of vaccination history or natural infection. Madagascar has used a combination of these activities to improve measles coverage. However, ongoing massive measles outbreak suggests that the country was in a “honeymoon” period and that coverage achieved needs to be re-evaluated. Although healthcare access is expected to vary seasonally in low resources settings, little evidence exists to quantify temporal fluctuations in routine vaccination, and interactions with other immunization activities. Methods: We used three data sources: national administrative data on measles vaccine delivery from 2013 to 2016, digitized vaccination cards from 49 health centers in 6 health districts, and a survey of health workers. Data were analyzed using linear regressions, analysis of variance, and t-tests. Findings: From 2013 to 2016, the footprint of SIAs and VWs is apparent, with more doses distributed during the relevant timeframes. Routine vaccination decreases in subsequent months, suggesting that additional activities may be interfering with routine services. The majority of missed vaccination opportunities occur during the rainy season. Health facility organization and shortage of vaccine contributed to vaccination gaps. Children born in June were the least likely to be vaccinated on time. Discussion: Evidence that routine vaccination coverage varies over the year and is diminished by other activities suggests that maintaining routine vaccination during SIAs and VWs is a key direction for strengthening immunization programs, ensuring population immunity and avoiding future outbreaks. Funding: Wellcome Trust Fund, Burroughs Wellcome Fund, Gates Foundation, National Institutes of Health.
KW - Healthcare access
KW - Madagascar
KW - Measles
KW - Vaccination
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U2 - 10.1016/j.vaccine.2019.02.069
DO - 10.1016/j.vaccine.2019.02.069
M3 - Article
C2 - 30940486
AN - SCOPUS:85063574375
SN - 0264-410X
VL - 37
SP - 2511
EP - 2519
JO - Vaccine
JF - Vaccine
IS - 18
ER -