{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:35:30Z","timestamp":1785404130970,"version":"3.56.0"},"reference-count":50,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,30]],"date-time":"2026-05-30T00:00:00Z","timestamp":1780099200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000030","name":"Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["NU66GH002172"],"award-info":[{"award-number":["NU66GH002172"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"award":["NU66GH002172"],"award-info":[{"award-number":["NU66GH002172"]}],"id":[{"id":"https:\/\/ror.org\/042twtr12","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: In Uganda, COVID-19-related disruptions increased the number of children who missed scheduled routine vaccination (defaulters). Identifying and following up with defaulter children is important for improving vaccination coverage. This paper describes Uganda\u2019s experience in revitalizing community-led defaulter tracking to improve vaccination coverage post-COVID-19 in four purposefully selected districts. Methods: During two 6-month periods in 2022 and 2024, healthcare workers (HCWs) worked with village health teams (VHTs) to review health facility-based immunization registers, identify and track defaulters aged 0 to 59 months. VHTs visited identified defaulters\u2019 homes, reviewed vaccination histories and reminded caregivers to bring defaulters to immunization sites for catch-up vaccination. Results: Overall, 20,922 defaulters were identified by health register review; VHTs located 15,749 (75.3%) through household visits, of whom 3688 (23.4%) were verified as previously vaccinated based on their home-based vaccination records, leaving 12,061 as true defaulters. Among the true defaulters, 9662 (80.1%) received at least one catch-up vaccination after follow-up by the VHT. The most frequently administered catch-up vaccines were measles\u2013rubella first dose (MR1) at 55.4%, followed by diphtheria\u2013tetanus\u2013pertussis third dose (DTP3) at 48.3% and Bacillus Calmette\u2013Gu\u00e9rin (BCG) at 47.4%. Among the 2399 children who remained unvaccinated after follow-up, the most common reasons were relocation outside the original catchment area (49.5%) and caregiver intention to vaccinate later (16.3%). Conclusion: Community-led defaulter tracking was feasible and improved vaccination uptake in post-COVID-19 Uganda. Strengthening the quality and availability of health facility immunization data, along with targeted community engagement, caregiver reminders and integrated vaccination services would improve identification and follow-up of defaulters, reducing population immunity gaps.<\/jats:p>","DOI":"10.3390\/vaccines14060490","type":"journal-article","created":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T12:45:08Z","timestamp":1780404308000},"page":"490","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Community-Led Defaulter Tracking for Catch-Up Vaccination: Implementation Experience in Uganda, 2022 and 2024"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0157-632X","authenticated-orcid":false,"given":"Joseph","family":"Magoola","sequence":"first","affiliation":[{"name":"African Field Epidemiology Network, Lugogo House, Kampala 12874, Uganda"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brooke N.","family":"Aksnes","sequence":"additional","affiliation":[{"name":"Global Immunization Division, US Centers for Disease Control and Prevention, Atlanta, GA 30329, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Immaculate","family":"Ampeire","sequence":"additional","affiliation":[{"name":"Expanded Program on Immunization, Ministry of Health, Kampala 7272, Uganda"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4346-8810","authenticated-orcid":false,"given":"Yvette","family":"Wibabara","sequence":"additional","affiliation":[{"name":"US Centers for Disease Control and Prevention, Kampala 1577, Uganda"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ciara E.","family":"Sugerman","sequence":"additional","affiliation":[{"name":"Global Immunization Division, US Centers for Disease Control and Prevention, Atlanta, GA 30329, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4310-0442","authenticated-orcid":false,"given":"Kirsten","family":"Ward","sequence":"additional","affiliation":[{"name":"Global Immunization Division, US Centers for Disease Control and Prevention, Atlanta, GA 30329, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1343","DOI":"10.1377\/hlthaff.2020.00103","article-title":"Return On Investment From Immunization Against 10 Pathogens In 94 Low-And Middle-Income Countries, 2011\u201330","volume":"39","author":"Sim","year":"2020","journal-title":"Health Aff."},{"key":"ref_2","unstructured":"World Health Organization (2022). 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