Home >News > ProMED翻訳情報(256回) ~オンタリオ州(カナダ)における2013年度の狂犬病の状況報告~

ProMED翻訳情報(256回) ~オンタリオ州(カナダ)における2013年度の狂犬病の状況報告~


Date: Wed 12 Mar 2014  Source: Ontario Ministry of Natural Resources (MNR)オンタリオ天然資源省 [edited]

2013 in review: rabies cases and control efforts
2013評価: 狂犬病症例と制御努力
All in all, 2013 was a good news year on the rabies front with only 28 cases reported in Ontario. There were 27 rabid bats and one rabid dog in total this year [2013].
The most welcome news of all was the lack of terrestrial rabies cases in southern Ontario. This was the 1st year since the 1950s (when rabies became established in this province) that there were no confirmed terrestrial rabies cases in southern Ontario. The only terrestrial case occurred in a puppy from a First Nation’s [various Aboriginal peoples in Canada who are neither Inuit nor Metis] community on the James Bay coast, in northern Ontario.
なかでも最も喜ぶべきは、南部オンタリオで陸生動物の狂犬病が発生しなかったことである。南オンタリオで陸生動物の狂犬病が確認されなかったのは、1950年代(狂犬病がこの地域で定着した時)以来最初の年である。唯一陸生動物での症例は、北部オンタリオのJames Bay沿岸にあるFirst Nation(イヌイットやメティス以外の様々なカナダ原住民)共同体の子犬で発生した。

During the final quarter of the year [2013], there were 6 rabid bats (Bruce, Halton, Lambton (2), Middlesex, and Toronto) bringing the total for 2013 to 27. The following was the species distribution of rabid bats in 2013: big brown (23), little brown (1), eastern red (1), and silver-haired (2). This is up slightly from the 25 rabid bats in 2012 but is still lower than the average of 29 cases for the past 5 years and 44 cases for the past decade.
2013年の最終四半期に、6例(Bruce, Halton, Lambton (2), Middlesex, Toronto)のコウモリ狂犬病が発生し、2013年発生総数が27件になった。2013年の狂犬病罹患コウモリの種分布は以下の通りである:big brown(23件)、little brown(1件)、eastern red(1件)、silver-haired(2件)。これは2012年のコウモリ狂犬病25件からわずかに増加しているが、過去5年間の平均29件や過去10年間の平均44件よりは少ない。

Southwestern Ontario
The low incidence of rabies in southwestern Ontario [SWONT] for 2012 and 2013 resulted in an approximately 40 percent reduction in the oral rabies vaccination (ORV) zone. The ORV zone is determined by adding an approximately 50 km [31 mi] buffer around confirmed terrestrial strain rabies cases in the current and previous year. Low density ORV is conducted to help prevent re-infection of fox populations by isolated cases of rabid skunks in SWONT, and to help to contain ‘Ontario fox’ train rabies to this area and prevent it from re-entry into the rest of southern Ontario.

Between 9 and 12 Sep [2013], 135 720 ultra-lite (UL) baits containing ONRAB(R) vaccine were distributed by MNR Twin-Otter (DHC-6) aircraft flying approximately 150 meters [492 ft] above ground. Baits were dropped over an area measuring approximately 9181 sq km [3545 sq mi] along flight lines spaced 2.0 km [1.2 mi] apart, at a density of 20 baits/sq km [52 baits/sq mi].
2013年9月9日から12日にかけて、135,720個のONRAB(R)ワクチンが入った超軽量(UL)餌がMNR Twin-Otter(DHC-6)航空機によって、上空150m(492ft)付近から散布された。餌は20個/平方キロメートル(52個/平方マイル)の密度で、2km(1.2mile)飛行間隔、9,181平方キロメートル(3,545平方マイル)の範囲にわたって落とされた。
The area baited this year [2013] was roughly bounded by Goderich on the west, Hanover on the north, Guelph on the east, and London on the south.

Additionally, 95 sq km [37 sq mi] of the Niagara area, which was inaccessible by helicopter, was hand-baited by 4 MNR field staff during the period of 3-6 Sep 2013. Staff drove around the areas inaccessible by helicopter, mainly high density urban areas such as the core of Niagara Falls and Fort Erie, tossing baits from vehicles at a density of approximately 300 baits/sq km [777 baits/sq mi], delivering 18 293 ONRAB(R) rabies vaccine baits to the area.
加えて、2013年9月3日から6日にかけ、ヘリコプターでは近づく事の出来ないNiagara地域の95平方キロメートル(37平方マイル)にわたって、4名のMNR野外スタッフが手作業で餌を散布した。スタッフはヘリコプターでは近づけない地域を車で回り、ナイアガラの滝の中心部やFort Erieなどの主に高密度の市街地に、車から餌をなげて約300個/平方キロメートル(777個/平方マイル)の密度で18,293個のONRAB(R)入り餌を散布した。

Southeastern Ontario
To prevent re-incursion of ‘raccoon’ variant rabies from New York State, UL baits containing ONRAB (R) were distributed in select areas along the St Lawrence River in [southeastern Ontario] SEONT. On 17 and 18 Aug 2013, 51 068 baits were distributed on Wolfe, Howe, Hill, Simcoe, and Grenadier islands in the St Lawrence River, as well as on 2 rectangular plots (831 sq km) near the international bridges in the Prescott and Ivy Lea areas. All baits were dropped along flight lines spaced 0.75 km [0.47 mi] apart and distributed at a density of 75 baits/sq km [194 baits/sq mi] over non-urban, agricultural, and forested habitats. The St Lawrence River area was once a hot spot for ‘raccoon’ strain rabies but Ontario has not had a case in 8 years.
ニューヨーク州から”アライグマ”変異型狂犬病が再侵入するのを防ぐため、ONRAB(R)が入った超軽量餌が、SEONT(オンタリオ南東部)のセントローレンス川に沿った選択地域に散布された。2013年8月17日から18日にわたって、51,068個の餌がWolfe, Howe, Hill, Simcoe, セントローレンス川中にあるGrenadier島、同じく、国際橋付近のPrescottとIvy Lea地域2長方形区画(831平方キロメートル)に散布された。全ての餌は0.75km(0.47mile)間隔の飛行線に沿って、75個/平方キロメートル(194個/平方マイル)の密度で非市街地、農業地、森林地帯に散布された。セントローレンス川地域は、かつて”アライグマ”型狂犬病の多発地域であったが、オンタリオでは8年間発生していない。

In addition to the aerial baiting, 945 baits were distributed by hand on [18 Aug 2013], in green spaces in Brockville owing to its proximity to cases on the US side of the St Lawrence.

Niagara Region
To prevent re-incursion of ‘raccoon’ variant rabies from New York State and to maintain a buffer of vaccinated raccoons on the Niagara peninsula, urban areas (300 baits/sq km [777 baits/sq mi]) and rural areas (75 baits/sq km [194 baits/sq mi]) were baited aerially using an EC130 helicopter (rotary wing). A total of 60 412 baits were distributed over 627 sq km [242 sq mi] during 26-29 Aug 2013. We were able to distribute baits more efficiently in many areas in 2013 using the EC130 helicopter, thereby reducing staff and time to complete the project.

Even though Quebec has been considered raccoon rabies free since 2010, the threat of a new introduction from the US is still real and worrying. In 2013, several positive cases were found in the neighbouring states, New York and Vermont. Moreover, 51 cases were found less then 80 km [49.7 mi] from the border. This preoccupying situation has lead us to keep our rabies surveillance and control program active and up to date, which was carried out for the 8th consecutive year.

During the year [2013], our enhanced surveillance activities allowed us to collect 880 specimens in the south area of Quebec, mainly in Estrie and Monteregie regions. Of these, 76 percent were raccoons, 20 percent were skunks and less than 4 percent were foxes. Most of these animals were collected through our road patrol (64 percent) or following a citizen report (28 percent). No positive cases were found this year [2013], for the 4th consecutive year. In comparison with 2012, we received 35 percent less reports from citizens (N = 797) and, therefore, 33 percent less specimens were collected from citizen reports (N = 260). However, our road patrol managed to keep up pace of specimen collection with an increase of 6 percent (N = 560).
2013年には調査活動の強化により、我々はQuebec南部、主にEstrie、Monteregie地域から880検体を集める事が出来た。これらのうち76%がアライグマで20%がスカンク、キツネは4%以下である。これらのうちほとんどの動物が道路巡視(64%)、または市民通報(28%)により集められた。4年間続けて今年 [2013] も陽性例は全く検出されなかった。2012年との比較では市民通報は35%減少(797件)し、そのため市民通報による検体蒐集は33%減少(260件)した。しかしながら、我々の道路巡視により検体収集率は6% (560件) 増加した。

Oral rabies vaccination (ORV) was conducted along the Quebec-US border, in the same regions as our enhanced surveillance activities. ORV operations included both hand (end of April and early-September) and aerial baiting (mid-August).

Overall, 651 065 ONRAB(R) baits were distributed over 8040 sq km [3104 sq mi]. In 2013, bait densities ranged from 60-80 baits/sq km [155-207 baits/sq mi] (hand baiting) to 75-125 bait/sq km [194-324 baits/sq mi] (aerial baiting).

The baits were distributed in preferred raccoon habitat, forest patches, and adjacent edges of agricultural fields.

A post-ORV study was conducted between 8 and 18 Oct 2013 to assess the percentage of raccoons that were positive for rabies virus antibodies in the area where ONRAB(R) baits were used. Blood serum was collected from a total of 455 raccoons distributed in three cells.
Antibody prevalence ranged between 47 and 56 percent (c-ELISA, CFIA).
抗体保有率は47から56%(c-ELISA,CFIA)であった。  [Byline: Beverly Stevenson]

[In the original document there is a map with the points where the rabid bats were found and a table with details by county.

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.