Post-acute sequelae after Lassa fever: A systematic review and meta-analysis

Post-acute sequelae are symptoms that persist or arise after the acute phase of an infection, but their frequency following outbreaks remains poorly understood. Recurrent Lassa fever outbreaks pose a significant public health threat in West Africa and may have long-term health effects. This study systematically reviewed the prevalence, incidence, duration, and characteristics of post-acute sequelae in survivors of Lassa virus infection. We searched PubMed and Web of Science up to November 17, 2025. Two reviewers screened and extracted data independently. We included six articles in the review. The most frequently reported post-acute sequela was hearing loss, with a pooled prevalence of 18% (95% CI 9-32) across 6 studies. Odds ratios for the association between Lassa fever and hearing loss were heterogeneous, with a statistically significant positive association in 2 of 5 studies and a positive effect direction in 2 further studies. Of an additional 37 potential post-acute sequelae, several with high prevalence also related to the audiovestibular system (e.g., tinnitus, balance disorder, and vertigo). Our findings highlight that Lassa fever survivors can experience diverse symptoms after recovery from acute infection, with hearing loss being the best-characterised. However, data gaps remain on its incidence after mild infections and its duration. A better understanding of post-acute sequelae after Lassa fever is necessary for accurate disease burden estimation and mathematical modelling studies.