Challenges Addressing Inequalities in Measles Vaccine Coverage in Zambia through a Measles-Rubella Supplementary Immunization Activity during the COVID-19 Pandemic.
Vaccines (Basel)
; 11(3)2023 Mar 07.
Article
em En
| MEDLINE
| ID: mdl-36992192
ABSTRACT
BACKGROUND:
Measles-rubella supplementary immunization activities (MR-SIAs) are conducted to address inequalities in coverage and fill population immunity gaps when routine immunization services fail to reach all children with two doses of a measles-containing vaccine (MCV). We used data from a post-campaign coverage survey in Zambia to measure the proportion of measles zero-dose and under-immunized children who were reached by the 2020 MR-SIA and identified reasons associated with persistent inequalities following the MR-SIA.METHODS:
Children between 9 and 59 months were enrolled in a nationally representative, cross-sectional, multistage stratified cluster survey in October 2021 to estimate vaccination coverage during the November 2020 MR-SIA. Vaccination status was determined by immunization card or through caregivers' recall. MR-SIA coverage and the proportion of measles zero-dose and under-immunized children reached by MR-SIA were estimated. Log-binomial models were used to assess risk factors for missing the MR-SIA dose.RESULTS:
Overall, 4640 children were enrolled in the nationwide coverage survey. Only 68.6% (95% CI 66.7%, 70.6%) received MCV during the MR-SIA. The MR-SIA provided MCV1 to 4.2% (95% CI 0.9%, 4.6%) and MCV2 to 6.3% (95% CI 5.6%, 7.1%) of enrolled children, but 58.1% (95% CI 59.8%, 62.8%) of children receiving the MR-SIA dose had received at least two prior MCV doses. Furthermore, 27.8% of measles zero-dose children were vaccinated through the MR-SIA. The MR-SIA reduced the proportion of measles zero-dose children from 15.1% (95% CI 13.6%, 16.7%) to 10.9% (95% CI 9.7%, 12.3%). Zero-dose and under-immunized children were more likely to miss MR-SIA doses (prevalence ratio (PR) 2.81; 95% CI 1.80, 4.41 and 2.22; 95% CI 1.21 and 4.07) compared to fully vaccinated children.CONCLUSIONS:
The MR-SIA reached more under-immunized children with MCV2 than measles zero-dose children with MCV1. However, improvement is needed to reach the remaining measles zero-dose children after SIA. One possible solution to address the inequalities in vaccination is to transition from nationwide non-selective SIAs to more targeted and selective strategies.
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Base de dados:
MEDLINE
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En
Ano de publicação:
2023
Tipo de documento:
Article