Epidemiology and molecular virus characterization of reemerging rabies, South Africa

The incidence of dog rabies in Limpopo Province, South Africa, increased from 5 cases in 2004 to 100 in 2006. Human rabies had last been confirmed in 1981, but investigations instituted after an index case was recognized in February 2006 identified 21 confirmed, 4 probable, and 5 possible human cases between August 5, 2005, and December 31, 2006. Twelve of these case-patients were identified retrospectively because the diagnosis of rabies was not considered: 6 of these patients consulted a traditional healer, 6 had atypical manifestations with prominent abdominal symptoms, and 6 of 7 patients tested had elevated liver enzyme activity. Molecular genetic analysis indicated that outbreak virus strains were most closely related to recent canine strains from southern Zimbabwe. Delayed recognition of the human cases may have resulted from decreased clinical suspicion after many years of effective control of the disease and the occurrence of atypical clinical presentations.     

狂犬病24例病例流行病学调查分析

目的调查2009年陕西省汉中市突发的狂犬病疫情情况,分析其发病的原因和影响因素,为有效的预防控制提供依据。方法对汉中市医疗机构诊断报告的24例狂犬病病例,收集病例临床诊疗资料,开展个案流行病学调查,用Excel2003软件进行统计分析。结果 2009年3—9月,汉中市辖区毗邻的6个平川县区先后发生24例狂犬病病例,发病率为0.63/10万。24例狂犬病例中农民23例(95.83%),其中有2例(8.33%)及时接受了伤口处理并接种了狂犬疫苗,2例(8.33%)接受了狂犬病疫苗接种但不及时,20例(83.33%)未进行规范的伤口消毒处理或未进行伤口处理。24例狂犬病例均为犬只暴露,以流浪犬为主,当地犬密度为1只/10人。结论犬只饲养量大,管理工作不到位,群众对狂犬病的危害性认识不足或缺乏认知,暴露后未接受处置或处置不及时不规范是造成本次狂犬病发病的主要原因。     

Reemergence of rabies in Chhukha district, Bhutan, 2008

From January through July 2008, rabies reemerged in the Chhukha district of southwestern Bhutan. To clarify the distribution and direction of spread of this outbreak, we mapped reported cases and conducted directional tests (mean center and standard deviational ellipse). The outbreak resulted in the death of 97 animals (42 cattle, 52 dogs, and 3 horses). Antirabies vaccine was given free of charge to ≈674 persons suspected to have been exposed. The outbreak spread south to north and appeared to follow road networks, towns, and areas of high human density associated with a large, free-roaming, dog population. The outbreak was controlled by culling free-roaming dogs. To prevent spread into the interior of Bhutan, a well-coordinated national rabies control program should be implemented in disease-endemic areas.     

湖南省泸溪县2005年家犬感染狂犬病毒调查分析

目的了解湖南省泸溪县家犬狂犬病病毒感染情况。方法对全县17个乡(镇)市售家犬采集脑组织,标本送省疾病预防控制中心经免疫荧光法初筛和RT-PCR方法确证检测狂犬病毒抗原。结果家犬脑组织狂犬病毒感染率为1.93%。结论泸溪县家犬存在一定程度的感染,需加强犬只免疫,对带毒犬只严格监控以及正确处理。     

阜阳市2005～2006年狂犬病流行因素分析

目的分析阜阳市2005～2006年狂犬病流行因素,探讨有效防制措施。方法对本市发生的所有狂犬病病人进行调查;选择有狂犬病的自然村对农村犬密度及犬免疫状况进行调查,设两个狂犬病门诊为暴露人群监测点。结果2005～2006年全市共发生43例狂犬病患者,年平均发病率为0.25/10万,病死率为100%;全市8个县（市、区）均有病例报告,以临泉县发病最多（14例）,占全市的32.56%;发病年龄最大77岁,最小2岁,儿童及青壮年发病较多;职业以农民为主,占72.09%;伤人动物以犬为主,占95.00%;伤口暴露部位以上肢为主,占57.50%;伤口以Ⅲ度伤为主,占80%;未进行伤口处理22例,占55.00%;未接种疫苗33例,占76.74%,接种疫苗者90%未全程免疫。门诊暴露人群以农民为主;各月均有暴露者,以6～8月份最多,占35.89%;最大年龄89岁,最小28天;暴露部位以下肢为主,占56.19%;咬伤程度以Ⅱ度为主,占53.63%。户犬密度为89.22%,犬的免疫率为34.62%。结论犬密度高,免疫率低,群众防病意识差,伤口处理不规范,未按规定程序进行免疫,是本市人间狂犬病流行的主要因素。     

Rabies in Estonia: situation before and after the first campaigns of oral vaccination of wildlife with SAG2 vaccine bait

Despite the extermination of stray animals and the compulsory vaccination of companion animals, rabies has been widely distributed over Estonia for more than 30 years. The red fox and the raccoon dog are the rabies virus reservoirs. Through a PHARE project, successive oral vaccination campaigns, using Rabidog SAG2 baits, were implemented in the autumn of 2005 in North Estonia, and in the spring and autumn 2006 throughout the whole territory. After the autumn 2005 campaign, 73.5% of the raccoon dogs and foxes were positive for the tetracycline biomarker. After the campaigns of 2006, the seroconversion rate for rabies virus was 64% in both species. After the vaccination campaigns of 2005 and 2006, the incidence of rabies cases dramatically decreased. Of the 97 cases diagnosed in the whole of Estonia until the end of May 2006, 16 cases (16.5%) occurred within the vaccinated area. Only 17 cases were diagnosed between 1 June and 31 December 2006. In 2007, by the end of May, only two rabies cases have been registered.     

2007年湖南省犬只感染狂犬病病毒情况调查

目的了解湖南省犬狂犬病病毒感染状况，为防制狂犬病提供科学依据。方法在湖南省14个市（州）的15个县（区）采集集市所售家犬脑组织，采用直接免疫荧光法标本狂犬病毒抗原，阳性者再用巢式RT-PCR方法检测标本狂犬病毒核酸。结果共检测845份犬脑组织标本，犬只狂犬病病毒感染率为2．60％，其中茶陵县、湘乡市、邵阳县分别为12．90％、6．38％和19．35％，其他12个县未检出狂犬病病毒。雄性、雌性犬只感染率分别是2．94％和1．37％。放养、圈养犬只感染率分别是2．65％和0．00％；不同性别、不同养殖方式的犬只病毒感染率差异无统计学意义（P均〉0．05）。与2005、2006年相比，2007年湘潭、邵阳两市的犬只狂犬病病毒感染率上升显著。结论湖南省家犬狂犬病病毒感染率较高，需加强犬只管理和免疫，有效预防和控制狂犬病的发生。     

天台县2001-2005年狂犬病疫情分析

目的分析天台县2001—2005年狂犬病流行情况,探讨其流行因素。方法收集2001—2005年天台县狂犬病疫情资料。结果2001—2005年天台县共发病11例,年平均发病率为0.4/10万,年发病率最高为1.07/10万。一年四季均有病例发生,发病最多的是每年的2～4月份。伤人动物均为犬类,咬伤后72.72%的患者伤口未作任何处理,90.90%未注射狂犬病疫苗。结论犬类养殖增加,患者暴露后未及时、规范处理伤口,未注射或未全程注射狂犬病疫苗等因素是导致天台县狂犬病疫情上升的原因。     

Enzootic Rabies Elimination from Dogs and Reemergence in Wild Terrestrial Carnivores, United States

To provide molecular and virologic evidence that domestic dog rabies is no longer enzootic to the United States and to identify putative relatives of dog-related rabies viruses (RVs) circulating in other carnivores, we studied RVs associated with recent and historic dog rabies enzootics worldwide. Molecular, phylogenetic, and epizootiologic evidence shows that domestic dog rabies is no longer enzootic to the United States. Nonetheless, our data suggest that independent rabies enzootics are now established in wild terrestrial carnivores (skunks in California and north-central United States, gray foxes in Texas and Arizona, and mongooses in Puerto Rico), as a consequence of different spillover events from long-term rabies enzootics associated with dogs. These preliminary results highlight the key role of dog RVs and human–dog demographics as operative factors for host shifts and disease reemergence into other important carnivore populations and highlight the need for the elimination of dog-related RVs worldwide.     

聊城市狂犬病流行病学特征及防制对策分析

目的分析聊城市狂犬病流行病学特征,探讨流行因素,为制定预防控制对策提供依据。方法采用描述流行病学方法,对2005~2006年22例狂犬病的个案资料进行分析。结果夏秋季节发病较多,发病范围主要集中在莘县、阳谷、东昌府,以男性农民为主;犬是主要传播宿主(86.4%),主要感染方式为咬伤(81.8%),受伤部位以头颈部为主(36.4%)。结论中重度受伤、近中枢部位受伤、多处受伤、伤口处理不够规范及疫苗接种率低,是导致狂犬病发生的重要因素。加强犬的管理,提高犬的免疫接种率和消灭野犬,规范暴露后伤口的处理及提高狂犬病疫苗接种率,是预防狂犬病疫情上升的主要防制策略。     

Inferior rabies vaccine quality and low immunization coverage in dogs ( Canis familiaris) in China

Human rabies in China continues to increase exponentially, largely due to an inadequate veterinary infrastructure and poor vaccine coverage of naive dogs. We performed an epidemiological survey of rabies both in humans and animals, examined vaccine quality for animal use, evaluated the vaccination coverage in dogs, and checked the dog samples for the presence of rabies virus. The lack of surveillance in dog rabies, together with the low immunization coverage (up to 2.8% in rural areas) and the high percentage of rabies virus prevalence (up to 6.4%) in dogs, suggests that the dog population is a continual threat for rabies transmission from dogs to humans in China. Results also indicated that the quality of rabies vaccines for animal use did not satisfy all of the requirements for an efficacious vaccine capable of fully eliminating rabies. These data suggest that the factors noted above are highly correlated with the high incidence of human rabies in China.     

Canine rabies vaccination and domestic dog population characteristics in the developing world: a systematic review

Background

Human rabies remains a significant problem in many developing countries, where canine rabies is the most common means of transmission. Although vaccination of dogs has been shown to be the most effective method of prevention in humans, dog vaccination is often lacking.

Methods

This systematic review examined dog rabies vaccination coverage achieved following mass vaccination campaigns and dog ecology/management factors relevant to rabies control in the developing world. We searched a variety of electronic databases for published articles pertaining to dog rabies vaccination or dog ecology where data were collected utilizing a household cluster survey. We reviewed studies published between January 1, 1980 and present and identified 29 articles for inclusion.

Results

We found the majority of vaccination campaigns were able to achieve the WHO recommended vaccination coverage of ≥70% and calculated weighted mean post-campaign vaccination coverage of 76.5% in urban areas and 73.7% in rural areas. However, we found an absence of studies related to dog vaccination/dog ecology from countries with the greatest burden of rabies such as India, China, and Pakistan. In addition, the majority of dogs in the developing world are very young and short-lived, reducing the effectiveness of vaccination campaigns.

Conclusions

Future studies on canine ecology should be undertaken in countries with high endemic canine rabies. New methods for improving the longevity of dogs and reducing high dog population turnover need to be investigated. Programs which encourage good dog management and promote responsible pet ownership are essential to eliminating canine and human rabies.     

Operational performance and analysis of two rabies vaccination campaigns in N’Djamena,Chad

Transmission of rabies from animals to people continues despite availability of good vaccines for both human and animal use. The only effective strategy to achieve elimination of dog rabies and the related human exposure is to immunize dogs at high coverage levels. We present the analysis of two consecutive parenteral dog mass vaccination campaigns conducted in N’Djamena in 2012 and 2013 to advocate the feasibility and effectiveness for rabies control through proof of concept. The overall coverage reached by the intervention was >70% in both years. Monthly reported rabies cases in dogs decreased by more than 90% within one year. Key points were a cooperative collaboration between the three partner institutions involved in the control program, sufficient information and communication strategy to access local leaders and the public, careful planning of the practical implementation phase and the effective motivation of staff.The dynamic and semi to non-restricted nature of dog populations in most rabies endemic areas is often considered to be a major obstacle to achieve sufficient vaccination coverage. However, we show that feasibility of dog mass vaccination is highly dependent on human determinants of dog population accessibility and the disease awareness of dog owners. Consequently, prior evaluation of the human cultural and socio-economic context is an important prerequisite for planning dog rabies vaccination campaigns.     

Failure of rabies postexposure treatment in Thailand

Three failures of postexposure rabies treatment using imported purified duck embryo cell and Vero cell rabies vaccines are reported from Thailand. Reference is made to eight additional previously reported Thai patients, six of whom had received human diploid cell vaccine. An analysis of these cases reveals that there were serious flaws in management in all of these patients. It is stressed that 45% of human rabies deaths in Thailand occur within 20 days of being bitten and 71% are dead within 28 days. This short incubation period does not allow much time to start immunotherapy. Of Bangkok dogs found to have rabies at autopsy, approximately 8% have a rabies immunization history. Once a dog has bitten a patient immunotherapy should not be delayed in countries with a high incidence of dog rabies. Patients with chronic disease, alcoholics and drug addicts may have an impaired immune response to postexposure rabies vaccines.     

No adverse effects of simultaneous vaccination with the immunocontraceptive GonaCon™ and a commercial rabies vaccine on rabies virus neutralizing antibody production in dogs

Parenteral vaccination campaigns are integral to the elimination of canine rabies. To maximize herd immunity in dogs, immunocontraception provided at the time of rabies vaccination should reduce fecundity and dog abundance. GonaCon™ has been used successfully as an immunocontraceptive in a variety of mammals, and by inference, the dog would be an ideal candidate for testing. As an initial step in evaluating a combination-vaccination program, we assessed the effects of GonaCon™ on rabies virus neutralizing antibody production in dogs after administration of a veterinary rabies vaccine. Eighteen feral/free ranging dogs were included in this initial study: six were given GonaCon™ only, six were given rabies vaccination only, and six received GonaCon™ and rabies vaccination. Antibody levels were evaluated over 82 days. The use of the immunocontraceptive GonaCon™ did not affect the ability of dogs to seroconvert in response to the rabies vaccine. Thus, GonaCon™ provides a potential immunocontraceptive for use in combination with rabies vaccine to increase herd immunity and address dog population over abundance to better manage rabies.     

2007～2008年高州市人狂犬病暴露与犬携带狂犬病病毒情况调查

[目的]了解高州市外观健康犬只狂犬病病毒携带情况和人群狂犬病暴露与处置情况,为提出狂犬病防制对策提供依据。[方法]收集2007年高州市犬只饲养与动物伤人资料,对2008年高州市某乡小学205名学生家长进行狂犬病知识与犬伤情况问卷调查,2008年7～9月在市场采集健康犬脑和及唾液腺检测狂犬病病毒。[结果]高州市2007年动物伤人12029例,其中被犬所伤者占80.46%。调查205人,85.37%听说过狂犬病,其中66.34%知道狂犬病是被动物伤所致;61.46%的家里养犬。检测200只犬的标本,均为狂犬病病毒阴性。[结论]高州市家养犬只数量多,犬伤暴露状况严峻,居民狂犬病相关知识知晓率不高,尚未发现携带狂犬病病毒的犬只。     

Phylogenetic analysis of nucleoprotein gene of dog rabies virus isolates from Southern India

India like several other South East Asian and African countries continues to face the public health and economic problems associated with the disease. Our objective was to perform a limited sequence analysis of a portion of nucleoprotein gene of 22 rabies virus isolates obtained from domestic animals in Southern India during 2004–2005. These isolates were compared with rabies virus isolates originating from Asia, Europe, Africa and North America. The phylogenetic analysis showed that RV isolates in Southern India belong to genotype 1. They were similar to one another forming a single major genetic cluster not ordered by geography or species of origin. However, they were dissimilar to RV isolates in Northern India and in other parts of the world. The data indicated that dog rabies virus variants are the major circulating viruses and control of dog rabies would result in overall reduction in the burden and incidence of rabies in India.     

A dog rabies vaccination campaign in rural Africa: impact on the incidence of dog rabies and human dog-bite injuries

Despite the availability of safe and effective rabies vaccines, the incidence of dog rabies has been increasing throughout much of sub-Saharan Africa. Here we describe a vaccination strategy that has resulted in successful control of rabies in a rural dog population of Northwestern Tanzania. From October 1996 to February 2001, four central-point dog vaccination campaigns were conducted in villages within Serengeti District with a mean interval between campaigns of 338, 319 and 456 days. Vaccination coverage of the dog population was estimated from household questionnaires as 64.5, 61.1, 70.6 and 73.7% following each of the four campaigns, respectively. The incidence of dog rabies declined significantly in Serengeti District falling by 70% after the first campaign and by 97% after the second campaign. Over the same period, the incidence of dog rabies did not differ significantly in unvaccinated control villages of Musoma District. The incidence of human bite injuries from suspected rabid dogs declined significantly in Serengeti District after dog vaccination but not in adjacent unvaccinated districts. Vaccination of 60-70% of dogs has been sufficient to control dog rabies in this area and to significantly reduce demand for human post-exposure rabies treatment. Dog-bite injuries can provide a valuable and accessible source of data for surveillance in countries where case incidence data are difficult to obtain.     

An outbreak of sheep rabies in Shanxi province, China

This study describes an outbreak of rabies in a flock of 110 sheep in Yangqu county, Shanxi province, China, in 2010. The flock, housed in a cave being used as a sheepfold, was attacked by a rabid dog, which resulted in 36 deaths over the following 2 days from the crushing and trampling caused by panic, and some 15 further deaths from rabies 2 weeks later. Rabies in the sheep was confirmed by the fluorescent antibody test (FAT) and RT-PCR. Rabies virus was isolated from the index dog brain and its N gene was partially sequenced (nucleotides 77-880). Results showed that the canine isolate (SXTYD01) was rabies virus with the N gene fragment 100% identical to that of the virus isolated from rabid sheep. This is the first confirmed sheep rabies outbreak in China. The clinical presentation of the disease is also described.     

上海市狂犬病流行病学分析及预防控制策略

目的 分析1950～2000年上海市狂犬病流行病学特征和评价预防控制策略。方法 开展病例流行病学调查,死亡病例病毒分离和间接荧光法测狂犬病毒IgG。结果 上海市狂犬病发病率1950年的1.98/10万为最高,1958～1988年无本地内源性感染病例,1989年至今共发生19例狂犬病病例。1985～2000年9月报告的20例狂犬病病例平均潜伏期66.37d,平均病程4.55d。其中705未经任何医疗预防处理。194例阳性犬咬伤者经及时全程医疗预防处理后,均未发病。结论 严格的犬类管理,及时伤口处理,注射狂犬病疫苗和抗狂犬病血清可以预防狂犬病和降低发病率。