Lagos Bat Virus in Kenya

Abstract

During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well adapted to its natural host species and that populations of reservoir hosts in eastern and western Africa have sufficient interactions to share pathogens. High virus concentrations, in addition to being detected in the brain, were detected in the salivary glands and tongue and in an oral swab, suggesting that LBV is transmitted in the saliva. In other extraneural organs, the virus was generally associated with innervations and ganglia. The presence of infectious virus in the reproductive tract and in a vaginal swab implies an alternative opportunity for transmission. The isolate was pathogenic for laboratory mice by the intracerebral and intramuscular routes. Serologic screening demonstrated the presence of LBV-neutralizing antibodies in E. helvum and Rousettus aegyptiacus fruit bats. In different colonies the seroprevalence ranged from 40 to 67% and 29 to 46% for E. helvum and R. aegyptiacus, respectively. Nested reverse transcription-PCR did not reveal the presence of viral RNA in oral swabs of bats in the absence of brain infection. Several large bat roosts were identified in areas of dense human populations, raising public health concerns for the potential of lyssavirus infection.

Possible Emergence of West Caucasian Bat Virus in Africa

“…Total RNA was extracted from the oral swabs (n = 931) and subjected to nested reverse transcription-PCR, as described previously (10). We used primers designed for the nucleoprotein genes of LBV, MOKV, and WCBV.…”

“…We used 4-well (6-mm) Tefl oncoated glass slides (Cel-Line, Erie Scientifi c, Portsmouth, NH, USA) as described elsewhere (10). Previous tests for RABV neutralizing antibodies have demonstrated that re-sults of this micromethod are comparable to those of the classical test in chamber slides.…”

Evidence of Lagos Bat Virus Circulation among Nigerian Fruit Bats

“…Both samples that demonstrated neutralizing activity against MOKV came from E. helvum in Karfi. Other studies in Africa record about 38% virus neutralizing activity to LBV among fruit bats in Ghana and Kenya (Hayman et al, 2008: Kuzmin et al, 2008.…”

“…Five other lyssavirus species, including Lagos bat virus (LBV), Duvenhage virus (DUVV), European bat lyssaviruses 1 and 2, and Australian bat lyssavirus have been reported in other parts of the world (WHO, 2005). More recently, four new putative lyssavirus species (Aravan, Kudjand, Irkut, and West Caucasian bat viruses) have been identified in bats (Kuzmin and Rupprecht, 2007).…”

“…Previously, LBV had been isolated from E. helvum, (Boulger and Porterfield, 1958;Kuzmin et al, 2008), M. pusillus, (Sureau et al, 1980), Rousettus aegyptiacus (Aubert, 1999), and Epomophorus wahlbergi, (Markotter et al, 2006). We obtained serologic evidence of LBV circulation in E. helvum and E. gambianus; however, viral infection was not detected, based on our limited dataset.…”