Bat population genetics and Lyssavirus presence in Great Britain.

(Accepted 13 November 2010; first published online 23 December 2010)SUMMARYMost lyssaviruses appear to have bat species as reservoir hosts. In Europe, of around 800reported cases in bats, most were of European bat lyssavirus type 1 (EBLV-1) in Eptesicusserotinus (where the bat species was identified). About 20 cases of EBLV-2 were recorded, andthese were in Myotis daubentonii and M. dasycneme. Through a passive surveillance scheme,Britain reports about one case a year of EBLV-2, but no cases of the more prevalent EBLV-1.An analysis of E. serotinus and M. daubentonii bat genetics in Britain reveals more structure inthe former population than in the latter. Here we briefly review these differences, ask if thiscorrelates with dispersal and movement patterns and use the results to suggest an hypothesis thatEBLV-2 is more common than EBLV-1 in the UK, as genetic data suggest greater movement andregular immigration from Europe of M. daubentonii. We further suggest that this geneticapproach is useful to anticipate the spread of exotic diseases in bats in any region of the world.Key words: Animal pathogens, genetics, lyssavirus, rabies (animal).INTRODUCTIONEuropean bats are host to two lyssaviruses: Europeanbat lyssavirus type 1 (EBLV-1), which is identified inmost of the >800 European cases [1] and Europeanbat lyssavirus type 2 (EBLV-2), which has only beenrecorded about 20 times [2]. Both cause fatal rabiesin humans, although cases are extremely rare. How-ever, contact with bats results in an unspecified num-ber of post-exposure prophylaxis (PEPs) in humanswithin Europe, e.g. Britain (H. Kirkbride, personalcommunication) and France [3] both record over100 per year. EBLV-1, is most closely related toDuvenhagevirus[4],andisgenerallyfoundinserotinebats (Eptesicus serotinus), which account for morethan 95% of cases where the bat species is identified[5]. E. serotinus is found across most of Europe, but isrestricted to southern parts of Sweden and England[6].TheE.serotinuspopulationsizeinBritainhasbeenestimated by extrapolation at 15000 [7]. In TheNetherlands alone, one-third of recovered bats thathad bitten humans tested positive for EBLV-1, and12% of bats recorded in contact with cats wereEBLV-1positive[8].EBLV-2ismostcloselyrelatedtoAustralianbatlyssavirus,andclassicalrabiesvirus[4],and has been recorded in Daubenton’s bat (Myotisdaubentonii) and the Pond bat (M. dasycneme).M. daubentonii occurs commonly across Europe,including southern Sweden, Norway, Finland andmost of Britain and Ireland. In Britain the population