@article{McCormack_M-2025_218410,
title = {Characterising protective immune responses to SARS-CoV-2 in urban and rural Malawi between February 2021 and April 2022},
author = {McCormack, M. and Banda, L. and Kasenda, S. and Hughes, E. and Leonhard, L. and Chauma Mwale, A. and McLean, E. and Price, A. and Crampin, A. and Chaima, D. and Amoah, A. and Nyirenda, T. and Ho, A. and Willett, B.},
month = {oct},
year = {2025},
abstract = {SARS-CoV-2 transmission in Malawi remains unclear due to high proportions of mild/asymptomatic infections and limited diagnostics. Existing seroprevalence studies in Malawi have primarily used convenience samples and enzyme-linked immunosorbent assays (ELISAs). We assessed SARSCoV-2 neutralisation in a longitudinal Malawian population-based cohort, assessing protective immunity post-infection and vaccination. Sera were obtained from rural (Karonga, n = 958) and urban (Lilongwe, n = 918) based participants at three-monthly intervals (February 2021-April 2022). Neutralising antibodies against SARS-CoV-2 were measured using human immunodeficiency (HIV)based pseudotype assays in HIV-uninfected participants, and vesicular stomatitis virus-based assays in HIV-infected participants and an HIV-uninfected subset. Nucleocapsid ELISAs identified vaccinated participants also infected. SARS-CoV-2 neutralisation profiles increased in complexity over time from rising vaccination coverage and emerging variants. Neutralising antibody prevalence was higher in Lilongwe than Karonga (68.1% (CI 63.5–72.4) vs. 45.4% (CI 41.6–49.3), Survey 4). Hybrid immune and solely vaccinated participants exhibited higher titres than those solely infected. Children &lt; 15 years had the lowest neutralising antibody titres among infected (not vaccinated) participants. People living with HIV had lower neutralising responses than those HIV-uninfected, particularly post vaccination. We therefore recommend surveillance of children and people living with HIV as low neutralisation responses increase reinfection risk. COVID-19 vaccination should be prioritised for HIV-infected individuals.},
volume = {15},
journal = {Scientific Reports},
publisher = {Springer Nature},
url = {https://doi.org/10.1038/s41598-025-22599-7},
}
