SARS-CoV-2 antibody immunity across three continents: the West Africa, West Indies, West London Consortium.

BACKGROUND: The experience of the COVID-19 pandemic has differed across continents. We hypothesized that regional differences in SARS-CoV-2 immunity might explain this observation. We therefore established the WWW Consortium in Ghana, W Africa; Jamaica, W Indies; and W London. Here, we describe the extent to which antibody immunity differs between these geographic locations. METHODS: The WWW Consortium harmonises across the HERITAGE (Accra, Ghana), WINDFall (Kingston, Jamaica) and Legacy (London, UK) studies, establishing sharing frameworks for samples, metadata, and data; related permissions and oversight; and associated physical and cloud infrastructure. With centralised testing, we performed serological assessments across all three locations at two snapshots in 2024 (April 1(st) - August 18(th); August 19(th) - December 31(st)) using high-throughput live virus neutralization and anti-nucleocapsid IgG, including n=763 individuals. FINDINGS: We found that across all sites most participants had detectable neutralising antibody titres against JN.1 and XEC - the predominant variants in 2024. There were site-related differences in immunity: vaccine-included SARS-CoV-2 strains were better neutralised by participants from the Legacy study - Ancestral, BA.5, XBB.1.5 initially, and JN.1 after a homologous booster in autumn 2024. For HERITAGE, neutralisation of both alpha- (HCoV-229E) and beta-coronaviruses (HCoV-OC43) was higher than WINDFall suggesting a cross-coronavirus serological response in West Africa. Finally, antigenic cartography identified two distinct antibody landscapes, with JN.1 and XEC antigenically distant in Legacy, but not in HERITAGE and WINDFall. INTERPRETATION: There is international heterogeneity in SARS-CoV-2 antibody immunity. Global recommendations for vaccine strain selection should incorporate data from diverse populations to ensure accurate, equitable recommendations. FUNDING: The Wellcome Trust.