Home >News > ProMED翻訳情報(245回) ~カナダで発見された狂犬病のコウモリの2事例~

ProMED翻訳情報(245回) ~カナダで発見された狂犬病のコウモリの2事例~


Date: Mon 3 Mar 2014  Source: Healthy Wildlife [edited]

The CWHC (Canadian Wildlife Health Center), Western and Northern Region, recently had 2 interesting big brown bat submissions. One bat had been submitted to a rehabilitation facility in October 2013 after being found on the ground by members of the public in Saskatoon. She had bruising around her shoulder and was described as “bitey” when being handled. The 2nd bat was found in a local church on 10 Jan 2014, captured in a container and taken to the same rehabilitation facility. This male bat had crusting lesions on his chin.
CWHC(Canadian Wildlife Health Center:カナダ野生動物衛生センター)は西部と東部地域で、最近2頭の興味深いオオクビワコウモリの提出を受けた。1頭はサスカトゥーンの市民メンバーにより地面で発見され、2013年10月に野生復帰施設に提出された。そのメスのコウモリは肩部周辺に打撲のような傷があり、捕獲されるときに咬もうとしたと記述されている。2番目のコウモリは2014年1月10日に地元の教会で発見され、容器に入れられて同じ野生復帰施設に連れて来られた。こちらのオスのコウモリは下顎部の傷が痂皮を形成していた。

The bats were housed individually under conditions that would induce normal torpor or hibernation but they were reluctant to drink and had lost weight. There was difficulty regulating the temperature of the hibernation chamber, with the temperature dropping below 4 deg C [39.2 deg F] rather than maintaining the desired temperature range of 6-9 deg C [42.8-48.2 deg F]. The bats subsequently died within 2 days of each other (the female on 16 Feb 2014 and the male on 18 Feb 2014) and were submitted for autopsy the following day.

On examination of brain tissues under light microscopy characteristic rabies virus inclusion bodies, so called Negri bodies, were observed and immunohistochemical stains, specific for rabies, confirmed the diagnosis. As there was no history of direct human contact, samples were not sent to the Canadian Food Inspection Agency (CFIA) rabies lab until after the diagnosis was made by CWHC.
光学顕微鏡下での脳組織の検査ではネグリ小体と呼ばれる特徴的な狂犬病ウイルスによる細胞質内封入体が検出された。また、狂犬病に特異的な免疫組織化学染色で確定診断がなされた。ヒトへの直接の接触という稟告がなかったので、CWHC(カナダ野生動物衛生センター)で診断が行われたあとまで検査材料はCanadian Food Inspection Agency(CFIA:カナダ食品監視局)狂犬病研究室へは送られなかった。

These cases are interesting for several reasons. First, it highlights the importance of bats as a source of rabies in Canada, and elsewhere, and the potential of bats to come into contact with humans. Big brown bats often hibernate in buildings and for that reason are found frequently by members of the public. Live bats are commonly taken to rehabilitation facilities due to public education campaigns stressing the importance of these often maligned animals.

Fortunately this rehabilitation facility had taken precautions to prevent human exposure. We have had similar situations in the past where bats have tested positive while being rehabilitated and precautions had not been taken which resulted in post-exposure treatment of people and considerable anxiety for those involved. These 2 cases are also interesting because of the long incubation period observed in these bats, assuming they were suffering from rabies at the time they were submitted to the rehabilitation centre and they did not have contact with each other.


Finally these cases are also noteworthy as it highlights the changing role of the federal Canadian Food Inspection Agency (CFIA) in rabies diagnosis and surveillance. The CFIA will only test animals for rabies when there is a human health risk but will confirm the diagnosis of positive tests from non-human health risk cases done in other laboratories. The Canadian Wildlife Health Cooperative, and other similar agencies, have now taken on primary responsibility for diagnosis and surveillance of rabies in wildlife. Appropriate precautions should always be taken when handling bats in order to prevent exposure to rabies and other diseases.

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ProMED-mail from HealthMap Alerts

[The big brown bat (_Eptesicus fuscus_) is native to North America,
Central America, the Caribbean, and extreme northern South America.
For a picture go to
オオクビワコウモリ(Eptesicus fuscus)は北アメリカおよび、中央アメリカ、西インド諸島、南アメリカの北端に棲息する。画像はこちら。
They can bite while being handled (see picture at

so manipulation of rabid animals by well-intentioned citizens is extremely dangerous.

Genetic evidence suggests that rabies is an old disease for bats in the New World. Bats from most of the estimated 41 bat species in the United States, when sampled in sufficient numbers, have been found to be infected with rabies virus. Rabies viruses recovered from bats were shown to be distinct from rabies viruses recovered from terrestrial mammals, suggesting that these viruses evolved within their bat hosts.

Bat rabies viruses are genetically diverse, exhibiting mutations characteristic to each host bat species. These data suggest that rabies viruses are maintained in animal populations predominantly through intraspecific transmission. That is, transmission rarely occurs between species, such as when a rabid bat infects a human. These “spillover events” generally are not perpetuated in the recipient species.

Portions of this comment were extracted from