Lassa Virus in Pygmy Mice, Benin, 2016-2017

Abstract

Lassa virus has been identified in 3 pygmy mice, Mus baoulei, in central Benin. The glycoprotein and nucleoprotein sequences cluster with the Togo strain. These mice may be a new reservoir for Lassa virus in Ghana, Togo, and Benin.

Figure

Bayesian phylogenetic analyses based on nucleotide sequences of the partial glycoprotein and nucleoprotein genes of Lassa virus (LASV), showing the placement of the new sequences (in boldface) isolated from Mus baoulei pygmy mice, in comparison with other sequences representing the members of LASV lineages I–IV. A) Glycoprotein, 1,408 nt; B) nucleoprotein, 1,654 nt. The trees are rooted by Gbagroube, a LASV-like virus isolated from Mus setulosus mice in Côte d’Ivoire. Statistical support of grouping from Bayesian posterior probabilities is indicated at the nodes. Country, strain names, and GenBank accession numbers are indicated on the branches. The analysis was inferred by using the Bayesian Markov chain Monte Carlo method implemented in BEAST (8). The following settings were used: general time reversible plus gamma, strict clock, and constant population. Markov chain Monte Carlo chains were run for 10 million states and sampled every 10,000 states to obtain an effective sample size >200 for all parameters. The new viral and murine sequences are deposited under accession nos. MH028396–404. Scale bars indicate nucleotide substitutions per site.