2013年8月1日 星期四

台灣鼬獾出現狂犬病! Rabies如何預防? (附狂犬病簡介)



Ferret




American Badger



Japanese Badger



最新資訊:

RABIES - TAIWAN (15): FERRET-BADGER, MORE CASES, RESEARCH, OIE
**************************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>

In this posting:
[1] OIE follow-up
[2] Oral vaccination, early preliminary trials

******
[1] OIE follow-up
Date: Thu 29 Aug 2013
Source: OIE WAHID Disease Information, reports archive, ref OIE 13994
[summ., edited]
<http://www.oie.int/wahis_2/temp/reports/en_fup_0000013994_20130829_165741.pdf>


1. Follow-up report no 22, submitted 29 Aug 2013
------------------------------------------------
Epidemiological comments: The Animal Health Research Institute
(National Laboratory) has confirmed rabies virus infection in 2 wild
ferret-badgers which were found in Nantou County, by direct
fluorescent antibody tests. From August 2012 to 25 Aug 2013, the
number of dogs and cats vaccinated against rabies is 386 923 in total
and consists of 70 396 in Taichung City, 67 095 in Tainan City, 13 326
in Hualien County, 34 496 in Nantou County, 12 521 in Pingtung County,
115 318 in Kaohsiung City, 19 700 in Yunlin County, 28 557 in Chiayi
County, and 25 514 in Taitung County. Intensified vaccination
activities targeted at dogs and cats still continue on the areas where
infected ferret-badgers were found. The monitoring is ongoing.

2. Outbreak summary [as of 29 Aug 2013]
---------------------------------------
Total outbreaks: 107 (submitted)
Species / Susceptible / Cases / Deaths / Destroyed / Slaughtered
Chinese ferret-badger / - / 106 / 105 / 1 / 0
Asian House Shrew / - / 1 / 1 / 0 / 0

[A map showing the location of the 107 outbreaks is included in the
report. - Mod.AS]

--
Communicated by:
ProMED-mail
<promed@promedmail.org>

[The summary report above includes details of the 107 outbreaks of
this unusual rabies epizootic in Taiwan.

The 1st 3 ferret-badgers to be found, by RT-PCR, as suspected rabies
cases by the National Taiwan University in June 2013 (subsequently
confirmed by the national laboratory), had been found dead on 23 May
2012 (Nantou county), 25 Nov 2012 (Yunlin county), and 29 Dec 2012
(Nantou county). Since the initial diagnosis, surveillance has been
widely implemented, discovering, so far, 102 additional
rabies-positive dead wild ferret-badgers and one dead Asian mouse
shrew, spread over the entire southern part of Taiwan (see map). In
addition, one (clinically affected?) wild ferret-badger was destroyed
(follow-up report No 4, Taitung City, T'ai-Tung, 28 Jul 2013).

There is no information, so far, on any suspected cases in other
animal species in Taiwan. - Mod.AS

Maps of Taiwan can be seen at
<http://www.chinatouristmaps.com/assets/images/city/taiwan-districts-map.jpg>
and <http://healthmap.org/r/8b8a>. - Sr.Tech.Ed.MJ]

******
[2] Oral vaccination, early preliminary trials
Date: Sat 24 Aug 2013
Source: Taipei Times [edited]
<http://www.taipeitimes.com/News/taiwan/print/2013/08/24/2003570477>


After visiting rabies-affected areas and laboratories in Taiwan,
specialists from the US Centers for Disease Control and Prevention
(CDC) yesterday [23 Aug 2013] praised the Taiwanese government's
"swift and comprehensive" response to the re-emergence of rabies in
the country and reported the preliminary results of their oral
vaccination study on ferret-badgers.

The specialist team arrived in Taiwan earlier this month [August 2013]
to assist health authorities on prevention measures and have been
working with the Taiwanese CDC and the Council of Agriculture to
identify clear strategies for rabies control.

Ryan Wallace, one of the 3 specialists, said "surveillance systems to
detect rabid animals have been in operation since the 1st reported
rabies case [and] the laboratory response to diagnose the disease,
which was previously not recognized in this country, has been equally
impressive."

"The full extent of the rabies reservoir in Taiwan is not yet
understood in its entirety. Further testing of rabies-suspect animals
and focused studies must be conducted before we could understand the
extent of the disease spread. For this reason, all counties and cities
in Taiwan should be considered potentially to have rabies in their
wildlife populations," he said.

Oral rabies vaccination requires years of planning, preparation, and
studies, Wallace said, before questions of what type of vaccine to
use, what type of bait to use, and how to target reservoir animals can
be adequately determined.

In the study, the specialists used 3 baits that are available in the
US and 3 ferret-badgers that were in captivity were offered the bait.

The goal of the study, in which only placebos, not actual vaccines,
were used, is to see if the coating on the bait would attract
ferret-badgers, and if it did attract them, how the bait would be
handled: actually ingested or simply chewed by the ferret-badgers.

"The ferret-badgers, unfortunately, did not seem very interested in
any of these baits," Wallace said.

Some placebo baits were also placed with cameras in settings where
ferret-badgers have existed, but no video of ferret-badgers
approaching the baits was obtained.

"The small preliminary study probably indicates that the baits we have
are probably not ideal for an animal the size of a ferret-badger, and
they may not be very good at attracting ferret-badgers to eat them,
which is required for vaccination," he said.

"In the US, we are currently using 2 types of vaccine for oral rabies
vaccination in wildlife, and both of those should be evaluated as
options for Taiwan if you decide to go the route of oral vaccination,
but it's a long process," he said.

Asked about the need for an animal experiment, Wallace said animal
model experiments play an important role in describing pathogenesis
and vaccine efficacy when a new virus or disease is found.

[Byline: Alison Hsiao]

--
Communicated by:
ProMED-mail
<promed@promedmail.org>

[In order to get orally vaccinated, the bait must be attractive for
the target animal and it must be thoroughly chewed in order to
guarantee that the sachet is punctured so that the vaccine is released
into the mouth of the consumer, exposing its oropharyngeal mucosa. The
investigators will have to determine the bait flavor preferences of
the target animals as well as their feeding behavior and physiology.
This will require a coordinated, multi-disciplinary, probably extended
research effort.

How and when was the virus introduced, as well as why infection is
limited to a single, wild species population, are other issues to be
addressed. - Mod.AS

台灣鼬獾出現狂犬病! Rabies如何預防?



台灣五十年來首度出現本土性動物狂犬病(rabies),南部一群鼬獾(ferret
badger)
受到不知來源的狂犬病毒感染,已經被全球報導。筆者2000年代在花蓮時有一位女性因狂犬病死亡,不過這案例是在中國受到狂犬咬傷,因為沒有錢接受疫苗注射,而發病死亡。不是本土性的。



狂犬病一發病就死亡,唯一治療法就是,一旦懷疑和有病毒的物質接觸、被動物咬傷、或接觸到可能帶病的動物唾液、或腦、神經組織,就需要接受疫苗注射。(有一例,是先生被動物咬傷,太太洗滌先生的衣物,接觸到動物體液而感染,發病死亡,先生卻沒發病! 約三十年前,有一篇個案報告,病人存活了,但是有很嚴重的後遺症! 最近的報導中,死亡率似乎只有80%,但存活者相信也有嚴重後遺症。)



用疫苗預防疾病的觀念始於1796年英國的Edward Jenner。他用牛痘(cowpox
virus)
病毒刮在人的皮膚上,以預防可能致命的天花(smallpoxvariola,死亡率越達三分之一)Jenner稱為vaccination (牛的拉丁文為vacca)(其實,Jenner之前1776Benjamin
Jesty
就用這方法給他家人預防感染,但並沒有像Jenner致力於其推廣。這段疫苗發展經過,詳見筆者 "微生物學史開天闢地的醫學拓荒者修訂版合記出版社,擔保很有趣哦!)



1881年法國的Louis Pasteur,發現將炭疽病菌(Anthrax) 輕度加熱,可以減低其毒性,再將此減毒細菌注射到羊群,可以預防羊群發生炭疽病。他隨Jenner所用名稱,將此用來預防疾病的減毒細菌稱為vaccine 。他又發現將發病的狂犬口中含有病毒的唾液種植在兔子腦中,等兔子發病死亡後,再取出腦組織,乾燥5-10日,可以減低其毒性,注射到人或動物,可以預防狂犬病。這種原始的狂犬疫苗Imrab,現在還用在動物。其效果比較差,又因為含有兔子腦組織,有可能會引起腦炎。



現在用於人的疫苗有很多種,例如在Diploid cell 培養病毒的human diploid cell rabies vaccine (H.D.C.V.,商標名Imovax),是1967年最早開始的無活性病毒疫苗(inactivated vaccine),是使用Pitman-Moore L503病毒株(毒性已減弱),到2006年已經給過一百五十萬人。



其他還有PCECV (purified chick embryo cell vaccine,商標名 Rabavert) Purified Vero cell
Rabies Vaccine (PVRV)
,以及RAV等等。 (RAV= Rabies Vaccine Adsorbed
Rhesus monkey vaccine GlaxoSmithKline產品,含有極少量beta-propiolactone,
aluminum phosphate, thimerasol, phenol red and the animal by products rhesus
monkey fetal lung cells
,都可能對人體有害。不過幾乎所有疫苗都含有一些此類物質,但極為微量,發生副作用的機率極低,其副作用和病毒、細菌會引起的疾病相較,注射疫苗的好處遠遠超過這些物質可能引起的毒性)



接觸病毒後的處置Post-Exposure
Prophylaxis (PEP)()




根據美國CDC的資料 [Centers
for Disease Control and Prevention. Use of a Reduced (4-Dose) Vaccine Schedule
for Postexposure Prophylaxis to Prevent Human Rabies: Recommendations of the
Advisory Committee on Immunization Practices (ACIP) MMWR 2010;59(No. RR-2)
],所有可能曾經和狂犬病毒有接觸的人,不論多久以前接觸,都通用(潛伏期可能長達兩年),都需要儘早接種疫苗。




處治傷口時,先用肥皂及水,徹底洗淨傷口。如有可能,使用可殺死病毒的Povidone-iodine之類藥物洗滌。



如果是以前沒有接受過疫苗注射者,需要先用全部劑量的HRIG (Rabies Immune Globulin,狂犬病毒免疫蛋白,20 IU/kg body weightPasteur Merieux Connaught產品的商標名ImoganBayer的產品稱為Bayrab) 注射到環繞傷口四週,然後將剩下的RIG肌肉注射。然後使用另外一支注射筒,注射HDCVPCECV
1.0 mL, IM
肌肉注射 (成人注射在上臂deltoid
area
,小孩注射在大腿前側方,因為注射臀部時,抗體反應比較差。要注意,須要注射到遠離傷口的部位,以免HRIG以及疫苗互相中和)。當天一劑,然後第3714天各一劑,共四次。



有免疫不全者,還要在第28天注射第五針。(本來免疫力沒有問題的人也都要注射第五針!)



如果這位是以前曾經使用過狂犬疫苗者,就不必要注射RIG 。曾經被注射過疫苗,曾經檢查出血中有抗體者,就不必再注射RIG。直接注射HDCVPCECV 1.0 mL, IM肌肉注射,當天第一劑,然後第三天再補一次。



疫苗的副作用



所有疫苗都可能有輕微的,甚至於嚴重的副作用。不過會有後遺症的嚴重副作用極為少見,和可能會出現的疾病比較,機率是差很多很多。



輕度的狂犬病疫苗副作用包括: 注射處紅、種、痛、癢 (30%-74%);頭痛、作嘔、腹痛、肌肉痛、頭昏(5%-40%)



中等度的副作用包括:蕁麻疹、關節痛、發燒 (發生在6% 的第二次以後注射之後)



其他有人報告發生神經系統毛病,例如Guillain-Barré
Syndrome (GBS)
,但是頻度低到和疫苗的關聯還不能確定。




每一公司的產品,其副作用可能有些差異。發生比較重的副作用,應該找醫師,同時填寫報告,告知衛生單位。美國有Vaccine
Adverse Event Reporting System (VAERS) form,或經 VAERS website athttp://vaers.hhs.gov/index,或電話給1-800-822-7967,可以給他們做統計用。(CDC:
1-800-232-4636 (1-800-CDC-INFO)
或找http://www.cdc.gov/rabies/



疫苗效果在注射兩劑之後,可以持續兩、三年。如果一年後再補一針,免疫力沒有問題者,十年後還有免疫力。



動物的狂犬病防疫



在有些國家或地區,規定寵物都要接受疫苗注射。Imrab 有幾種產品: Imrab, Imrab 3 (可用於Ferret), 以及 Imrab Large Animal



1984年美國費城的Wistar Institute成功地用基因重組方法,將狂犬病毒基因的Glycoprotein插入vaccinia virus(牛痘病毒,人的感染幾乎沒有症狀),作成 recombinant vaccine,稱之為 V-RG,是可以用口服餵食野生的動物、鳥類,防止動物的狂犬病 (商標名 Raboral)。此疫苗耐熱,可以將少量活病毒包在食餌內,空投到動物出沒處。在美國、比利時、法國、德國成功地用來野生動物的狂犬病流行。德國到2008年十一月,已經有兩年沒有新的狂犬病例出現。







附註 (取自筆者 "傳染病防治手冊" 2002年,藝軒。可能因為案例少,查不到更新的知識)


Rabies virus
(
狂犬病毒)

l RNA病毒,屬genus Lyssavirus的一種rhabdovirus ,可引起人畜共通疾病(zoonosis)



l 宿主:幾乎所有哺乳類動物都可以為宿主,以狗(dog)、狐狸(fox)、狼(wolf)、胡狼、臭鼬鼠、浣熊等為主,其他包括貓(cat)、蝙蝠(bat)、老鼠(rodent)等。



l 人乃是經由被帶有狂犬病病毒之動物咬傷或舐舔,傷口感染而致病。



l 本病屬全球性疾病,但台灣、日本、英國、愛爾蘭、挪威、瑞典、葡萄牙、澳洲、紐西蘭、新幾內亞、太平洋島嶼、西印度及大西洋群島之一部份,目前動物群中無病例。



l 潛伏期:3~8週。



l 具感染力時期:在狗、貓等動物發病前3~7天至整個發病期。



病變



l 狗之臨床表現可分為三期,常在發病後5~7天死亡。(1)前驅期:狗的性情改變,微燒、畏光、瞳孔擴張等。(2)狂躁期:3天後狗變的更興奮、流口水、躲在暗處。(3)痲痺期:病犬喉部肌肉痲痺無法進食,最後陷入昏迷而死亡。



l 人被感染發病時會有焦慮、頭痛、發燒、咬傷部位異樣感,接著出現痲痺、飲水時吞嚥困難(hydrophobia),且併有精神錯亂及抽搐現象,最後因呼吸痲痺而致死。



診斷



l 由接觸病史和臨床表現來診斷。



l 發病72小時內由鼻咽分泌物做病毒培養,通常2~6天可分離出病毒。



l 可由動物之腦部組織或頸背髮跟部之皮膚切片做螢光染色或病毒培養。



防治



l 寵物應定期注射動物用狂犬病疫苗。切勿任意棄養寵物,進口的動物需經檢疫,勿飼養走私動物。



l 被溫血動物咬傷應立即洗滌並消毒傷口。



l 將咬傷人之動物留觀十天,如果動物沒發病,人就不會感染此病。



l 台灣非狂犬病疫區,被狗或其他溫血動物咬傷,可不必打狂犬病免疫球蛋白或疫苗。



l 被患有狂犬病動物咬傷之患者,應於48小時內注射一劑人用狂犬病免疫球蛋白,以中和傷口病毒。並注射五劑人用狂犬病疫苗:第一劑在疑似狂犬病動物咬傷後立即注射,其餘在第一劑注射後之第371430天時施打。疫苗副作用包括注射部位局部疼痛、發癢,及頭痛、嘔吐、暈眩,甚至可能發生腦炎。人用狂犬病免疫球蛋白及疫苗需至衛生署防疫處或檢疫總所憑診斷書和處方箋領取。



RABIES - TAIWAN (07): FERRET-BADGER, MORE CASES
***********************************************
A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org

[1]
Date: Sun 4 Aug 2013
Source: The China Post [edited]
http://www.chinapost.com.tw/taiwan/national/national-news/2013/08/04/385512/13-new.htm


Thirteen ferret-badgers were confirmed to be infected with rabies yesterday [3 Aug 2013], breaking the record for the highest number of confirmed rabies cases within a day, according to the Council of Agriculture (COA). According to the COA, there have been a total of 35 confirmed cases of ferret-badgers with rabies as well as one house shrew since the 1st rabies case was discovered.

The COA said that Chiayi County became the 7th area with confirmed rabies cases, along with Kaohsiung City, Taitung County, Nantou County, Taichung City, Tainan City and Yunlin County. The 13 newly confirmed ferret-badgers with rabies, the COA said, were discovered [among] the 33 animal samples, including house shrews, squirrels and bats, but only those 13 ferret-badgers tested positive for rabies. Centers for Disease Control (CDC) chief Chang Feng-yee said that it is not a surprise that all the rabies-infected cases are ferret-badgers. "There might be more ferret-badgers confirmed to carry the rabies virus," Chang said, "but people should not panic about the increasing number of rabies cases." Chang Shu-hsien, head of the Bureau of Animal and Plant Health Inspection and Quarantine (BAPHIQ), said that even though the number of rabies cases dramatically increased, the government still has the situation under control.

Alishan, one of the popular tourists spots for domestic and international travelers, became one of the 3 areas in Chiayi County to have rabies-infected ferret-badgers. Chan Shu-hsien said that the COA has issued a notice to ban tourists from bringing pets to all the forest recreation areas and national parks. "All the local animal disease centers have personnel touring around mountain areas to give pets rabies vaccinations," Chang Shu-hsien said, "and some of the centers are currently short-handed."

Chang Shu-hsien said that all local governments can work with instructors and students from local schools and universities of veterinary sciences to assist with the vaccinations and the BAPHIQ will reimburse part of the cost. According to Chang Shu-hsien, the BAPHIQ immediately provided nearly 10 000 rabies vaccines for animals to those areas where newly confirmed rabies cases were discovered, including Chiayi County. Chang Feng-yee yesterday [3 Aug 2013] said that people who have been bitten or scratched by ferret-badgers from May 2012 to 31 Jul 2013 can receive publicly funded rabies vaccinations after evaluations.

This new policy originally targeted people who were bitten or scratched between August 2012 and July 2013, according to Chang Feng-yee, but considering the 1st rabies-infected ferret-badger was discovered last May [2012], the CDC decided to extend the period that this new policy covers.

[Byline: Joy Lee]

**********************

RABIES - TAIWAN (13): FERRET-BADGER, QUESTIONS
**********************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
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Date: Wed 14 Aug 2013
Source: The Taipei Times [edited]
<http://www.taipeitimes.com/News/editorials/archives/2013/08/14/2003569637/2>


A possible misdiagnosis of rabies
---------------------------------
On 17 Jul 2013 the Council of Agriculture made its initial report to
the World Organization for Animal Health [OIE] concerning the rabies
situation in Taiwan. In the pathogen field it had identified the cause
of the disease as "Lyssavirus", entering "not typed" in the blood type
field.

By Thu 1 Aug 2013, when the council issued its 5th report, it
identified the blood type as "RABV", which is the rabies virus. The
designation RABV generally refers to the strain of rabies that is
fatal to carnivores: dogs, cats, and humans. It is unknown on what
basis the council decided to revise the report in this way. Since May
[2013], when the 1st case of rabies infection in a ferret-badger was
discovered, until today [14 Aug 2013], with cases of rabies infection
limited to central, southern, and eastern Taiwan, there have been no
cases of rabies infection in dogs, cats, or humans. Isn't that rather
strange?

According to the Analysis of the Taiwan Isolation Rabies Genetic
Sequencing issued by the council, the similarities between the rabies
virus in ferret-badgers and the strain found in China is under 90 per
cent, so it should be regarded as a different virus [that is, strain].
Yet this lab says that the virus is closest to the one found in China.
Differences in the nucleoprotein genetic sequences of all Lyssavirus
strains can be used to determine where the virus exists. Changes in
the glycoprotein sequence can be used to evaluate the strain's
antigenicity -- the ability of an antigen to bind with an antibody --
toxicity and pathogenicity, which is the potential of a virus to cause
a disease. However, the glycoprotein sequence provided by the council
lab was too short. It did not show the antigenic determinants for the
virus' antigenicity or pathogenicity
.

At the moment, we can only make a comparison of these 2 limited
protein sequences, and speculate that the strain of the virus found
infecting ferret-badgers in Taiwan is a different type to that found
in China, which means the ferret-badger virus here is not the dog
rabies virus that everyone imagines it to be. The council should look
into this. The conditions of the so-called rabies outbreak in Taiwan
are increasingly clear: up until 5 Aug 2013 the virus had only been
found in 44 ferret-badgers and one shrew. As I understand it, there
have been many incidences of dogs being bitten by ferret-badgers in
the areas in which the latter have tested positive for the virus, and
of dogs coming home with ferret-badgers clamped in their jaws, and yet
we are still to have one case in which a dog has been found to be
infected.


Also, according to provisions by the Centers for Disease Control for
ferret-badger bites or scratches, anyone who has been bitten or
scratched by a ferret-badger over the past year can be given free
rabies vaccinations. As of 5 Aug 2013, a total of 815 people qualified
for the vaccination, of which 27 were actually bitten by one of the
animals.
That figure could be lower than the actual amount of people
who have been bitten, and many were bitten several months ago, but no
cases of rabies infection in people have emerged yet. It is quite
clear that the ferret-badger virus in Taiwan is not the same as the
rabies virus that is fatal to dogs and humans.


The glycoprotein genetic sequence provided by the council is too short
to be useful in determining whether the rabies vaccination currently
used in Taiwan offers protection against the virus found in the
ferret-badgers. In 2010, researchers in China discovered with rabies
viruses taken from ferret-badgers that several isolation strains were
of low pathogenicity or had no toxicity at all
. Lab rats were injected
in their brains with large amounts of the virus, but they did not
develop the disease. The council has yet to provide any data to
establish whether the nature or pathogenicity of the virus found in
Taiwan's ferret-badger population means that it will harm dogs, cats,
or people, let alone to clarify the efficacy of vaccinating dogs and
cats against it.

According to the Central Epidemic Command Center, there will be plenty
of vaccines available by late this month [August 2013], with 1.13
million [doses?] for dogs and cats and 47 000 for humans. Fortunately,
the pathogenicity of the ferret-badger virus in Taiwan for dogs, cats,
and people is very low or non-existent.
Are the vaccines being
provided at the state's expense to prevent "genuine" rabies useful
against the ferret-badger virus? My feeling is that these are just
vaccinations being administered to give peace of mind.

[byline: Liou Pei-pai, former director Taiwan Animal Health Research
Institute; translated by Paul Cooper]

--
communicated by:
Merritt Clifton
Editor, Animal People
PO Box 960
Clinton, WA 98236
USA
<anmlpepl@whidbey.com>
<http://www.animalpeoplenews.org>

[This press article might be dismissed as no more than a conspiracy
theory, if the author had not previously been a director of the Taiwan
Animal Health Research Institute. The article contains much new
information that has not been available in English language sources so
far and deserves careful reading. It seems likely that a few people
and at least one dog have been bitten in encounters with
ferret-badgers.

The author concludes that the Council of Agriculture has yet to
provide any data to establish whether the nature or pathogenicity of
the virus found in Taiwan's ferret-badger population means that it
will harm dogs, cats, or people, let alone to clarify the efficacy of
vaccinating dogs and cats against it. - Mod.CP]


 




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