Clinical and epidemiological profile of suspected and laboratory-confirmed measles cases in South Kivu, Democratic Republic of the Congo, 2023

Measles remains a major public health challenge in many low-resource settings, despite repeated vaccination efforts. In 2023, a resurgence of suspected measles cases was reported in South Kivu Province (Democratic Republic of Congo) following a mass vaccination campaign targeting children aged 6–59 months. This study aimed to describe the clinical and epidemiological characteristics of suspected measles cases and to identify factors associated with measles IgM positivity in the post-campaign period. A cross-sectional study was conducted among children aged 6–59 months presenting with clinical signs of measles in five health zones most affected by the outbreak (Kalehe, Minova, Idjwi, Miti-Murhesa, and Kalonge). Suspected cases were enrolled exhaustively from line lists provided by local health authorities. After obtaining parental consent, blood samples were collected and tested for measles and rubella IgM antibodies at the National Institute for Biomedical Research (INRB). Data were analyzed using R version 4.3.3. Logistic regression was used to identify characteristics associated with measles IgM positivity among suspected cases. Of the 82 children tested, 39 (48%) were positive for measles IgM. Among the 43 IgM-negative children, 8 (18%) were rubella IgM positive. In adjusted analyses, measles IgM positivity showed an evidence of an association with male parental decision-making regarding child vaccination (aOR :7.22; 95% CI: 1.64–43.2; p = 0.015) and others workers (aOR: 8.28; 95%CI:1.19-48; p = < 0.008). Despite reported high administrative vaccination coverage, measles continues to circulate among children in South Kivu. Strengthening immunization service quality, improving outreach to unvaccinated children, and engaging male parents and others workers may enhance vaccine acceptance and reduce measles transmission in the post-campaign period. Not applicable.