Survey on the prevalence of rabies in bats in Finland
Two European Bat Lyssaviruses (EBLVs) are known in Europe, of which the type EBLV-1 is mostly found in Serotine bats, whereas EBLV-2 mainly occurs in Daubenton's bats and Pond bats. So far EBLV-2 infections in animals are only reported for bats, whereas two cases of EBLV-2 infections in humans have been confirmed: in 1985 in Finland and 2002 in Scotland. Both cases involved unvaccinated persons engaged in bat research. Regardless of these cases, the risk of humans contracting bat rabies is considered low.
During the project, blood and saliva samples will be collected from bats in Turku, the island of Kakskerta in particular, in Uusimaa and in Southeast Finland. The aim is to gain samples from approximately 600 bats.
Because the research methods used do not involve killing healthy and symptomless bats, the project is in accordance with bat conservation. University researchers are responsible for collecting the samples, while Evira is in charge of laboratory tests for rabies. The collection of samples began in June and will continue until the autumn, except for during the period in which female bats give birth and lactate. In addition to collected samples, bats found dead, either in nature or buildings, will be examined.
In Finland, European bat rabies was confirmed for the first time in bats in August 2009, when the EBLV-2 (European bat lyssavirus-2) was isolated in a Daubenton's bat. The bat in question ( Myotis daubentonii) was sent from the island of Kakskerta in Turku to Evira for testing. Rabies was suspected because the bat had behaved in a strange manner. In bats, typical rabies symptoms include the uttering of certain sounds, odd behaviour, apathy and, on the other hand, aggressive outbursts. The encounter of bat rabies will not affect to the rabies-free status of Finland.
Epidemiologically, bat rabies is not considered the same disease as classic rabies. Cases are extremely rare, even in areas where bat rabies is known to have occurred for a long time, e.g. in Denmark, Germany and the British Isles. The number of reported cases of rabies in bats totals almost 900 in Europe, but no precise data is available on the actual occurrence of the disease.
Funding for the research project is being provided by the Ministry of Agriculture and Forestry.
Bats and collection of samples:
Thomas Lilley, Researcher, University of Turku, tel. +358 (0)40 5587783
Eeva-Maria Kyheröinen, Researcher, Finnish Museum of Natural History, tel. +358 (0)40 7218561
Bat rabies and rabies diagnostic:
Miia Jakava-Viljanen, Senior Researcher, Evira, tel. +358 (0)50 3510308
Tiina Nokireki, Researcher, Evira, tel. +358 (0)50 4131687