犬科动物病毒

Part 1：狂犬病毒（Rabies Virus，RABV）

狂犬病是由狂犬病病毒RABV感染引起的人兽共患病，症状是急性脑炎或脑膜脑炎，一旦发病，病死率几乎100%。所有温血动物都能感染狂犬病病毒，狐狸、狼等是最易感的动物，蝙蝠、兔子等属于高易感动物，犬、羊、马等为中度易感动物。人类的主要传染源是患犬，据世界卫生组织估计，全球每年有5.5万至10万感染病例，在该病盛行的地区，近99%的患者是因患犬咬伤或抓伤而感染病毒。

Rabies is a zoonotic disease caused by infection with the rabies virus RABV. The primary symptom is acute encephalitis or meningoencephalitis, and the fatality rate is almost 100%. All warm-blooded animals can be infected with rabies virus. Foxes and wolves are the most susceptible, bats and rabbits are highly susceptible, and dogs, sheep and horses are moderately susceptible. The main source of infection for humans is dogs. The World Health Organization estimates that there are between 55,000 and 100,000 cases of infection worldwide every year. In areas where the disease is prevalent, nearly 99% of patients are infected from dog bites or scratches.

RABV属弹状病毒科，病毒粒子形态呈典型的子弹状，长约130~240nm，直径65~80nm。RABV是负链RNA病毒，可编码五种结构蛋白：核蛋白（N）、磷蛋白（P）、基质蛋白（M）、跨膜糖蛋白（G）和RNA多聚酶（L）。狂犬病病毒在机体内的过程可分为三个阶段：繁殖期、侵入期、扩散期。第一阶段，在被患犬咬伤后，RABV颗粒就会随唾液进入暴露的肌肉组织中，并在其中聚集繁殖。第二阶段，RABV颗粒从肌肉细胞中出芽，而后进入神经肌肉接头的突触间隙、进入外周神经；一旦进入神经，RABV就会像子弹一样迅速移行，直达中枢神经系统。第三阶段，RABV进入中枢神经系统后向周围神经扩散，神经受损会使机体出现恐水、呼吸困难和吞咽困难等临床症状。

RABV belongs to the family Rhabdoviridae. The virions are typically bullet-shaped, about 130~240 nm in length and 65~80 nm in diameter. RABV is a negative strand RNA virus that encodes five structural proteins: nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G), and RNA polymerase (L). The progress of rabies virus in the body can be divided into three stages: reproduction, invasion and diffusion. In the first stage, after a dog bites, RABV particles enter exposed muscle tissue with saliva, where they accumulate and reproduce. In the second stage, RABV particles sprout from muscle cells and then enter the synaptic cleft of the neuromuscular junction and enter the peripheral nerve. Once inside the nerves, the RABV travels like a bullet to the central nervous system. In the third stage, RABV enters the central nervous system and diffuses to the peripheral nerves. The damaged nerves lead to clinical symptoms such as hydrophobia, dyspnea and dysphagia.

据报道，在自然发生的狂犬病病例中，犬在出现中枢神经系统症状前的潜伏期范围为3至24周，人类病例的潜伏期从几天到几年不等，多数是 2- 3 个月，暴露部位（即被咬伤部位）越靠近中枢潜伏时间越短，仅 2% -3%的人狂犬病病例潜伏期大于 1 年。

It has been reported that the incubation period before the onset of central nervous system symptoms in dogs in naturally occurring cases of rabies ranges from 3 to 24 weeks. In human cases, the incubation period varies from a few days to a few years, generally is 2-3 months. The closer the exposed site (i.e., the bitten site) is to the center to the center of the body, the shorter the incubation time. Only 2%-3% of human rabies cases have an incubation period greater than 1 year.

人类狂犬病患者临床表现可分为三个期：前驱期、兴奋期和麻痹期。前驱期患者会出现厌食、疲惫、头疼和发热等症状，通常持续2~10天。兴奋期可分为两型，即狂躁型和麻痹型，前者最熟知的表现就是恐水，麻痹型患者常见症状有肢体软弱、共济失调和肌肉瘫痪等。麻痹期时患者逐渐安静，患者昏迷、呼吸骤停。狂犬病的整个病程持续时间7~10天。

The clinical manifestations of human rabies patients can be divided into three stages: prodrome stage, excitation stage, and paralysis stage. Prodrome patients experience symptoms of anorexia, fatigue, headache and fever, which usually last two to 10 days. The excitement phase can be divided into the manic and paralysis stages, with the former including the familiar fear of water, and paralysis patients having common symptoms of weakness, ataxia and muscle paralysis. In the paralytic phase, the patient gradually quiets, falls into a coma, and goes into respiratory arrest. The entire course of rabies lasts 7 to 10 days.

狂犬病的处理原则是“防大于治”，因为一旦发病将无药可医。据世界卫生组织狂犬病专家磋商会第三版报告，﹥95%人狂犬病病例是由狂犬咬伤所致，因此家犬应该每年都注射狂犬疫苗，争取做到群犬免疫。世界动物卫生组织OIE与WHO的建议，犬只的免疫覆盖率应该达到70%，这其实也是世界范围内公认的、能有效的控制和清除狂犬病传播的免疫覆盖水平；其次，若不慎被宠物狗或者流浪狗抓伤或咬伤，应立即用肥皂水、洗涤剂、聚维酮碘消毒剂等溶液彻底冲洗和清洗伤口15分钟以上，并在医生的指导下进行狂犬疫苗接种及免疫球蛋白注射。此外，对伤人动物进行严密医学观察，10天后如果健康则没有罹患狂犬病风险。当然，保持尽量避免犬的舔舐或者无心的抓咬，将亲密距离控制在一定范围之内。

The principle of rabies management is prevention, because once the disease develops, there is no cure. According to the third edition of the WHO Expert Consultation on Rabies, >95% of human rabies cases are caused by bites, and domestic dogs should therefore be vaccinated against rabies every year to achieve herd immunity. The World Organization for Animal Health (OIE) and WHO recommend that the immunization coverage of dogs should reach 70%, which is actually the recognized immunization coverage level worldwide that can effectively control and eliminate the transmission of rabies. A person who is accidentally scratched or bitten by a pet or stray dog should immediately rinse and clean the wound thoroughly with soapy water, detergent, povidone iodine disinfectant and other solutions for more than 15 minutes, and carry out rabies vaccination and immunoglobulin injection under the guidance of a doctor. In addition, the injured animals should be kept under close medical observation; if they are healthy after 10 days, there is no risk of rabies. Of course, in the end, dog bites, licks, and scratches should be avoided, and a certain distance should be maintained.

Part 2：犬细小病毒（Canine Parvovirus，CPV）

犬细小病毒CPV是造成犬传染性腹泻的常见病因，这是一种烈性传染病。感染CPV患犬的临床症状可分为肠炎型和心肌炎型，肠炎型患犬病初表现出体温升高、食欲不振和呕吐，发病一天后开始腹泻，病初粪便呈稀粥状，随着病情的发展，开始出现血便且气味腥臭，患犬排便次数不定；心肌炎型多见于40日龄左右的幼犬，有的突然出现呼吸困难后死亡、有的出现不同程度的腹泻后死亡。目前没有CPV会感染人的证据。

Canine parvovirus (CPV) is a common cause of infectious diarrhea in dogs, a severe infectious disease. The clinical symptoms of CPV-infected dogs can be divided into enteritis type and myocarditis type. Dogs with enteritis initially show elevated body temperature, loss of appetite and vomiting, and one day after the onset of the disease, diarrhea begins. The feces are thin porridge at the beginning of the disease, and with the development of the disease, bloody stools and odor begin to appear, and the frequency of defecation of the affected dogs is variable. Myocarditis is more common in puppies about 40 days of age, some died after sudden dyspnea or different degrees of diarrhea. There is no evidence that CPV can infect humans.

病原体CPV的传染力极强，主要通过粪口途径传播，在宠物店和犬舍这种密集场所，发病率更是升高。细小病毒是小型的、无包膜的单链DNA病毒，在环境中可以存活很长一段时间。使用家用漂白剂、过硫酸钾、过氧化氢或一些高浓度的化学消毒剂（如戊二醛和邻苯二甲醛等）即可灭活病毒。按时接种疫苗是预防犬细小的最有效手段，未接种疫苗或接种疫苗效果不佳的成年犬也有可能患病。

The pathogen, CPV, is highly contagious and spreads mainly through the faecal-oral route, especially in crowded places such as pet stores and kennels. Parvoviruses are small, uncoated, single-stranded DNA viruses that can survive in the environment for a long time. The virus can be inactivated using household bleach, potassium persulfate, hydrogen peroxide, or a high concentration of chemical disinfectants such as glutaraldehyde and phthalaldehyde. Regular vaccination is the most effective way to prevent parvo in dogs. Adult dogs that have not been vaccinated or whose vaccination was ineffective may get sick.

当未免疫犬出现前文所描述症状时，可以初步判定为犬细小，但确诊还需特异性诊断。宠物医院一般会进行CPV核酸检测，该方法需要专业的核酸检测仪器，敏感性高；很多宠物医生也会选择进行血凝-血抑试验，该方法操作简单，但敏感度较低。当然，实验室测定可以通过电镜观察，可以看到大小均一且散在分布的病毒粒子，若是感染后期，由于肠黏膜分泌性抗体存在，病毒粒子呈聚集状态。随着病原体快速检测试剂的发展，宠物主人还可以选择在家操作，该检测操作方便，目前是大部分宠物医院及宠物主人首选的检测方法。

When an unimmunized dog presents with the symptoms described above, it can be preliminarily diagnosed as canine parvus, but specific diagnosis is needed to confirm the diagnosis. Pet hospitals generally conduct CPV nucleic acid testing, which requires professional nucleic acid testing equipment and is highly sensitive. Many pet doctors also choose to perform clotting and blood suppression tests, which are simple to perform but less sensitive. Of course, under electron microscopy the virions of uniform size and scattered distribution can be seen. In the later stages of infection, the virions are aggregated, due to the presence of secretory antibodies in the intestinal mucosa. With the development of pathogen rapid detection reagents, pet owners can also choose to test at home. This test is convenient to operate, and is currently the preferred detection method for most pet hospitals and pet owners.

具体操作如下：取新鲜的患犬粪便，将其与稀释液混合均匀后，用吸管吸取混合液4滴，加样至胶体金试纸板的样本孔内，等待样本在试纸板上充分扩散，5-10 分钟读取结果，C线为质控对照线，T线为样本检测线。结果试纸板同时出现C线和T线，表示结果为阳性，提示所检测的样本中含有检测的病毒。

The specific testing method is as follows: take fresh dog feces, mix it evenly with diluent, absorb 4 drops of the mixture with a straw, add the sample to the sample hole of the colloidal gold dipstick, wait for the sample to fully diffuse on the dipstick, and read the result in 5-10 minutes. Line C is the quality control line, and line T is the sample detection line. The C and T lines appear simultaneously on the test board to indicate that the tested sample contained the virus.

Part 3：犬冠状病毒（Canine Coronavirus，CCV）

随着新冠肺炎疫情在全球的爆发，冠状病毒引起人们的关注。在电子显微镜下，病毒包膜上的突起使其看上去像是皇冠，因此被称为“冠状病毒”。冠状病毒是已知基因组最大的RNA病毒，有四个属，其中，犬肠道冠状病毒CCoV属于a-属，犬呼吸道冠状病毒CRCoV属于b-属。冠状病毒基因组容易发生突变，已有证据表明犬冠状病毒可以跨种传播给猫，并且二者病原血清型之间发生基因重组。目前没有证据证明CCoV与CRCoV会感染人。

With the outbreak of the novel coronavirus around the world, coronavirus has drawn people’s attention. Under an electron microscope, the bumps on the virus’s envelope make it look like a crown, hence the name coronavirus. Coronavirus is the largest known genomic RNA virus, （Coronavirus is known as the RNA virus with the largest genome）and it has four genera. Of these, dogs are vulnerable to Intestinal Coronavirus (canine enteric coronavirus, CCoV) of the a-genus, and Respiratory Coronavirus (canine respiratory coronavirus. CRCoV) of the b-genera. The coronavirus genome is prone to mutation; there is evidence that canine coronavirus can be transmitted to cats, and genetic recombination occurs between the two pathogenic serotypes. There is no evidence that CCoV and CRCoV infect humans.

我国科研人员在2018年至2019年间收集了213份腹泻宠物犬的粪便样本，发现51份呈CCoV阳性。感染CCoV病毒的患犬主要表现出呕吐和腹泻，通常仅感染CCoV症状轻微，但是如果患犬之前已经感染了犬细小病毒等病原体，混合感染会导致高死亡率。 感染CRCoV的患犬主要表现出较轻的上呼吸道症状，但如果轻症没有得到及时的治疗，病原体向下呼吸道入侵，可能会发展为严重的肺炎，导致死亡。

Chinese researchers collected 213 stool samples from dogs with diarrhea between 2018 and 2019, and found 51 were positive for CCoV. Dogs infected with CCoV mainly show vomiting and diarrhea, and are usually only mildly infected with CCoV. However, if the dog is already infected with pathogens such as canine parvovirus, mixed infections can lead to high mortality. Dogs infected with CRCoV mainly show mild upper respiratory symptoms, but if mild cases are not treated promptly, the pathogen can invade the lower respiratory tract and develop into severe pneumonia, leading to death.

此外，CRCoV与犬流感病毒、犬副流感病毒，以及细菌、支原体等混合感染，导致狗狗反复咳嗽，这就是对幼犬危害严重的传染性呼吸道疾病，俗称“犬窝咳”，需要格外留意。

CRCoV, canine influenza virus, canine parainfluenza virus, as well as bacteria, mycoplasma and other infections can produce coughs, and pose a serious danger to puppies. Infectious respiratory disease, commonly known as “kennel cough”, should be taken seriously.

Part 4：感染狐狸的病毒

这是狐狸扎入深雪生擒老鼠的图像，据计算，一只狐狸可以控制2万亩范围的鼠害，这种无副作用方式可以有效保护生态环境健康。狐狸全身都是宝，有着极高的经济价值。狐狸拥有高颜值，尤其野生的红狐、雪狐、蓝狐、白狐，拥有“漂亮的眼线、惊人的脸颊”。我国是允许饲养狐狸的，但需要办理相关的饲养许可证。当然只有非野生、非保护动物类别的狐狸才能作为宠物饲养，而且要到专门的养殖基地购买，以免携带致病性病原体。

This is the image of a fox diving into deep snow to capture a mouse alive. It is calculated that a fox can control rodent infestation in an area of 20,000 acres, and this method of pest control has no side effects and can effectively protect the health of the ecological environment. Foxes also have high economic value, especially the wild red, snow, blue and white foxes, which have “beautiful eyeliner and amazing cheeks.” People wishing to keep foxes in China must obtain a special license. Of course, only non-wild, non-protected foxes can be kept as pets, and they must be purchased from specialized breeding bases to avoid transmission of pathogens.

随着养狐业的发展，以及狐狸作为“异宠”存在，携带的各种病毒也引发各方关注。2022年4月报道，一只狐狸在美国国会山附近咬伤9人，这只狐狸已被执行安乐死，并在其体内检测出了狂犬病病毒。狐细小病毒病具有高度传染性，临床表现为以呕吐、腹泻和脱水为特征的出血性肠炎，呈地方性暴发流行，死亡率高，危害性大，要格外留意。近年来，挪威等多个欧洲国家、以及加拿大等国家、相继发现高致病性禽流感病毒感染了野生狐狸、且导致死亡，这些动物可能充当中间宿主，将变异的病毒传播给人类及其他野生动物。

With the development of fox breeding and the fashion for foxes as unusual pets, various viruses carried by foxes have also caused concern. In April 2022, it was reported that a fox that bit nine people near the U.S. Capitol was euthanized and the rabies virus was detected in its system. Fox parvovirus disease is highly infectious, and its clinical manifestations are hemorrhagic enteritis, characterized by vomiting, diarrhea and dehydration. This disease, with high mortality and great harm, and merits special attention. In recent years, highly pathogenic avian influenza viruses have been found to have infected and killed wild foxes in several European countries, including Norway, as well as in Canada, and these animals may also act as intermediate reservoirs to transmit the mutated influenza virus to humans and other wildlife.

狐狸模样可爱，即使经过专门去掉汗腺后体味不明显，但是排泄物依然非常难闻，还有咬人的坏习惯，作为宠物一定要慎重，然而一旦入手都应负责到底，不能随意抛弃。

The fox looks lovely, and after the removal of sweat glands the body odor is not obvious, but the excrement is smells very bad. Foxes also tend to bite, and people should be cautious about keeping them as pets. Once a fox is adopted, of course, the owner should be responsible to the end; foxes cannot be abandoned at will.

Part 5：感染貉的病毒

大家都很熟悉“一丘之貉”这个成语，那你了解主人公“貉”这一物种吗？貉（学名：Nyctereutes procyonoides）体型短而肥壮介于浣熊和狗之间，与狐狸和狼为近亲，体色乌棕，吻部白色，四肢短呈黑色，尾巴粗短。脸部有一块黑色的“海盗似的面罩”。貉属于国家二级保护动物，但是可以人工养殖繁育，是近几年农民致富项目之一。貉是珍贵的毛皮动物之一，貉子皮毛绒为我国传统的出口商品，貉子肉是高级滋补品，貉子胆入可药。

Everyone is familiar with the idiom “be tarred with the same brush（一丘之貉）”. Do you know the species? Raccoon dogs (Nyctereutes procyonoides) are short and stout, halfway between raccoons and dogs, closely related to foxes and wolves. They are dark brown in color, have a white snout with a “pirate mask,” short black limbs and a stubby tail. Raccoon dogs are among the second-class national protected animals. But they can be bred artificially, which has been a profitable business for farmers in recent years. Raccoon skin is a precious fur, raccoon skin plush is a traditional export commodity of China, raccoon meat is considered to be tonic, and raccoon fat is considered medicinal.

纵观全国，近两年各地貉出没的报道并不少见。上海是貉的原产地，野生貉可能是在自然迁徙的过程中，从野生环境来到了人类居住的小区。新冠疫情期间，上海很多小区楼栋门口的湿垃圾成为貉获取食物的来源之一，也在无形中将貉拉进了居民的生活圈。 2021年在上海150个小区里发现大概5000只貉，个别区域目前呈现泛滥态势。

Across the country, raccoon dog sightings have not been uncommon in the past two years. Shanghai is the origin of raccoon dogs. Wild raccoon dogs may have migrated from the wild environment to the human community during their natural migration. During the COVID-19 pandemic, wet garbage at the gates of many residential buildings in Shanghai has become a source of food for raccoon dogs, bringing them into the orbit of residents. In 2021, about 5,000 raccoon dogs were found in 150 residential districts in Shanghai, and some areas are now overrun. A 10-minute standoff between raccoon dogs and humans in Shanghai aroused public concern. Raccoon dogs may attack humans and dogs, posing a safety hazard to residents in the community. Raccoon dogs also carry viruses such as parvovirus and canine distemper, which can cause devastating mortality in entire populations. Raccoon dogs can also carry the rabies virus, and a human bitten by a raccoon dog should get a rabies vaccine.

上海“人-貉对峙10分钟”引发了大众关注，貉会主动攻击人类，攻击宠物狗，给小区内的居民带来了一定的安全隐患。貉也会携带细小病毒、犬瘟热病毒，甚至新冠病毒。犬瘟热一旦发生便可造成全群毁灭性死亡。貉也可能会携带狂犬病毒，如果被貉攻击，需要及时注射狂犬病毒疫苗。

最后，貉具有很强的野性以及一定的攻击性，存在安全隐患，因此并不适合做宠物。

In March 2023, the leading international journal Science reported that raccoon dogs may be an important link in the process of COVID-19 jumping from bats to humans. Raccoon dogs are very wild and aggressive, and pose security risks to humans. They are stronger than domestic dogs, so they are not suitable for pets.

总编辑：牛立辰

文本：宫冉冉，黄薇

翻译：王晓佳

导演及编辑：雷逸雪

解说：雷逸雪