Lassa fever infection from West Africa, dynamic and epidemiology of the virus on the population 1969–2019: a systematic review and meta-analysis

Abstract

Background Lassa virus (LASV) is a highly prevalent arenavirus that affects two to three million people in West Africa. This rodent borne virus which has serious consequences on the population and hospital staff in endemic areas. In this article, we review prevalence of LASV with a focus on the dynamic and epidemiology of the disease of 1969-2019. What informs on the evolution and the extent of the disease in this at-risk zone in order to prepare response measures in the event of an epidemic. Methods We was conducted a retrospective review through literatures search using the AGORA, PubMed, Science Direct, Scopus, researchgate and Google scholar Database on Lassa fever (LF) from West Africa. A total 34 articles were studied from 11 countries. Studies were categorized by host and country, and meta-analysis conducted to determine pooled prevalence estimates for each category Analysis was done using the metaprop command in STATA version 15 and MetaXL software. Results A total of 18.111 individual samples from 11 countries, described in 34 articles were studied. Meta-analysis of twenty six studies have indicated that the pooled prevalence was 19.0% [95% CI (15.0-23.0%), I2 = 97.93%]. There was a high level of heterogeneity between studies; however, the high prevalence of LASV was noted in several countries as Nigeria (12-42%), followed by Sierra Leone (8-43%), and then Guinea (9-40%). Pooled prevalence of LASV for human in studies conducted over the entire review period was 22.0% [95% CI (17.0-28.0%), I2 = 98.0%]; eighteen studies), while she was 9.0% [95% CI (4.0-15.0%), I2 = 97.0%]; eight studies) for Mastomys spp. Conclusion The knowledge of the geographical distribution and epidemiology may have help for disease control efforts and limit the risk of transmission, both locally and internationally. This study is also important in order to guide interventions, public health authorities and inform on the evolution of the disease and its magnitude in the population.

A prospective, multi-site, cohort study to estimate incidence of infection and disease due to Lassa fever virus in West African countries (the Enable Lassa research programme)–Study protocol

“…A study in Guinea reported seroprevalence of Lassa IgG to be 40.3% and IgM to be 2.8% [ 12 ]. Similar high LASV seroprevalence has been reported in Sierra Leone (8–40%) [ 11 , 13 ]. Since 2014, Benin has been experiencing LF outbreaks almost every year, predominantly in the northern regions of the country, but no data exist on the incidence of the disease in Benin (A. Akim Adegnika, personal communication, 1 st August 2022).…”

“…Nigeria has been reporting LF outbreaks almost every year, and annually since 2007 (A. Olayinka, personal communication, 16 th July 2022). Studies have shown the LASV prevalence among Nigerian population ranged from 12–42% [ 11 ]. A study in Guinea reported seroprevalence of Lassa IgG to be 40.3% and IgM to be 2.8% [ 12 ].…”