Equine encephalosis virus: evidence for circulation beyond southern Africa.

The research paper discusses the geographical spread of the equine encephalosis virus (EEV), previously confined to South Africa, across other parts of Africa and its potential as a common ancestor to the virus strain involved in a recent outbreak in Israel. The study also proposes that the Sahara desert could be limiting the virus’s spread northwards.

Study of EEV’s Geographical Spread

• The research primarily focuses on the geographical spread of EEV, a virus that affects equids like horses. Up until an outbreak in Israel in 2009, the virus was thought to be limited to South Africa.
• The study purports to present the first pieces of evidence showing the prevalence of EEV beyond South Africa, specifically in East and West African countries such as Ethiopia, The Gambia, and Ghana.
• Based on the findings, the research suggests that the virus is freely circulating and endemic in these regions of Africa, implying that it has a firm and established presence in local equine populations.

Evidence of Common Ancestry to the 2009 Outbreak Strain

• Through sequence analysis, the isolated strain of EEV in The Gambia was found to be closely related to a strain isolated from a horse in Israel during the 2009 outbreak.
• This significant discovery suggests that the two viruses likely share a common ancestry. The findings hint at a potential pathway or vector that may have carried the virus strain to Israel, leading to the outbreak of equine encephalosis there in 2009.

The Sahara as a Geographical Barrier

• An intriguing aspect of the research is the observation that horses in Morocco, a North African country, did not possess EEV antibodies.
• This suggests that the virus has not yet managed to infiltrate the northern parts of Africa, with researchers positing that the Sahara desert may be acting as a geographical barrier.
• The vast desert landscape could restrict the transmission vectors from moving north, thereby confining the EEV’s spread south of the Sahara.

Implications of the Study

• The findings raise further questions about the modes of transmission and the factors that facilitate or obstruct the virus’s spread.
• These new insights into the geographical movement and ancestry of EEV offer a solid foundation for additional research into mitigating the spread and impact of EEV.