New Perspective on the Geographic Distribution and Evolution of Lymphocytic Choriomeningitis Virus, Central Europe

Area of Science:

• Virology
• Evolutionary Biology
• Ecology

Background:

• Lymphocytic choriomeningitis virus (LCMV), an Old World mammarenavirus, is globally distributed due to its association with house mice.
• LCMV spillover to humans can cause aseptic meningitis in immunocompetent individuals and severe systemic infection or death in immunocompromised persons.

Purpose of the Study:

• To investigate LCMV prevalence and evolutionary history in natural mouse populations within a key hybrid zone in Central Europe.
• To characterize novel LCMV variants and determine the correlation between viral phylogeny, host subspecies, and geographic origin.

Main Methods:

• LCMV prevalence was assessed in house mouse populations across a Czech Republic-Germany transect.
• Genomic sequencing was performed on newly identified LCMV variants from the Czech Republic.
• Phylogenetic analysis was used to infer evolutionary relationships between LCMV strains and their mouse hosts.

Main Results:

• The study identified a clear division in the LCMV phylogenetic tree that directly corresponds to the two main house mouse subspecies: Mus musculus musculus and M. musculus domesticus.
• LCMV strains found in human infections were consistently linked to the specific mouse subspecies prevalent at the spillover site.
• Two new LCMV variants were genetically characterized from mouse populations in the Czech Republic.

Conclusions:

• The genetic structure of house mouse populations serves as a strong predictor for the type of LCMV strains that may spill over into human hosts.
• Understanding LCMV-host interactions within distinct mouse subspecies is crucial for predicting zoonotic transmission risks.