20 research outputs found
The Impact of Human Conflict on the Genetics of Mastomys natalensis and Lassa Virus in West Africa
Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago). Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease
Shedding dynamics of Morogoro virus, an African arenavirus closely related to Lassa virus, in its natural reservoir host Mastomys natalensis
Genomic profiling of host responses to Lassa virus: therapeutic potential from primate to man
Multiple Circulating Infections Can Mimic the Early Stages of Viral Hemorrhagic Fevers and Possible Human Exposure to Filoviruses in Sierra Leone Prior to the 2014 Outbreak
Field evaluation of a Pan-Lassa rapid diagnostic test during the 2018 Nigerian Lassa fever outbreak
Arenavirus infection correlates with lower survival of its natural rodent host in a long-term capture-mark-recapture study
Parasites & Vectors 2018, Vol. 11:90Background: Parasite evolution is hypothesized to select for levels of parasite virulence that maximise transmission
success. When host population densities fluctuate, low levels of virulence with limited impact on the host are
expected, as this should increase the likelihood of surviving periods of low host density. We examined the effects of
Morogoro arenavirus on the survival and recapture probability of multimammate mice (Mastomys natalensis) using
a seven-year capture-mark-recapture time series. Mastomys natalensis is the natural host of Morogoro virus and is
known for its strong seasonal density fluctuations.
Results: Antibody presence was negatively correlated with survival probability (effect size: 5–8% per month depending
on season) but positively with recapture probability (effect size: 8%).
Conclusions: The small negative correlation between host survival probability and antibody presence suggests that
either the virus has a negative effect on host condition, or that hosts with lower survival probability are more likely to
obtain Morogoro virus infection, for example due to particular behavioural or immunological traits. The latter
hypothesis is supported by the positive correlation between antibody status and recapture probability which
suggests that risky behaviour might increase the probability of becoming infected.DOI 10.1186/s13071-018-2674-