Symptoms & Prevention of Canine Rabies in Shih Tzu Dogs

Canines infected with rabies are highly susceptible to transmitting the virus to other animals and humans. Wild animals that carry the infection can harbor the virus for extended periods, serving as natural reservoirs for rabies in the environment. The virus primarily targets the central nervous system, with the hallmark symptom being "hydrophobia," hence the alternate name "hydrophobia disease."

Rabies Pathogen:

Rabies virus is classified under the Rhabdoviridae family and the genus Lyssavirus. The virus can survive for long periods in cold or freezedried conditions, but it can be inactivated by sunlight, ultraviolet light, 70% ethanol, iodine alcohol, and other disinfectants.

Epidemiology:

Rabies is a disease that can affect all mammals, but due to the virus predominantly residing in the central nervous system and saliva, and considering the close relationships between dogs, cats, and humans, these animals are the most common sources of rabies transmission. Since dogs are highly susceptible to the virus, it is crucial to administer rabies vaccines promptly to prevent transmission to humans.

The virus is primarily found in the brains of infected animals. During the illness, the salivary glands and saliva contain a high concentration of the virus, which is excreted outside the body.

Rabies is mainly transmitted through bites that break the skin and mucous membranes; it can also be contracted through the respiratory tract via the air; ingestion of infected animals or interanimal fights can lead to infection through the digestive system; and in humans, dogs, and laboratory animals, rabies can be vertically transmitted through the placenta.

The disease can occur yearround, but the incidence is higher during spring and summer, which may be related to the increased sexual activity of dogs. Spring is the season when dogs are in heat, leading to more interactions with other animals. Also, animal movement is more frequent during warm seasons.

The disease's prevalence is characterized by a regional pattern, appearing in a scattered, sequential manner. The closer the wound is to the head or forelimb, or the deeper the wound, the higher the incidence.

Symptoms of Rabies in Shih Tzus:

Infected dogs typically have an incubation period of 2 to 8 weeks, which can last up to a year or more. The incubation period is shorter for dogs with head and facial wounds or deeper wounds. The duration of the incubation period also depends on the amount of virus, its virulence, and the host's immune response. Typical symptoms are categorized into three stages:

1. Prodromal stage: During the early stages, Shih Tzus may exhibit abnormal behavior, such as running and hiding. They may prefer dark places and may disappear for several days before returning. There is no significant change in body temperature.

2. Furious stage: The infected Shih Tzu shows increased reflex excitement, reacting aggressively to light, sudden noises, and touches. The dog may run around, potentially biting humans and other animals. The dog's behavior becomes abnormal and extremely aggressive, with possible symptoms of anorexia and vomiting.

Hydrophobia is a unique symptom of rabies, but it may not be present in every case or appear early on. Typical symptoms include spasms of the throat when drinking, seeing water, or hearing running water, causing the dog to appear very thirsty but unable to drink or swallow, leading to dehydration. Fear of wind is also a common symptom, with even a gentle breeze or crosswind triggering spasms in the throat muscles. The dog may salivate excessively, with body temperatures reaching above 40 degrees Celsius, rapid heart rate, increased blood pressure, dilated pupils, and a rapid progression of the disease, often resulting in death due to respiratory or circulatory failure.

3. Paralytic stage: After the furious stage, the disease progresses to the paralytic stage. The Shih Tzu may experience flaccid paralysis, particularly in the limbs. The muscles of the eyes, face, and mastication may also be affected. Breathing becomes slow and irregular, the heartbeat weakens, consciousness is impaired, and the dog ultimately dies due to respiratory or circulatory paralysis.

How to Diagnose:

Comprehensive diagnosis: If a dog shows signs of swallowing difficulties, a blocked throat, aggressive behavior, sudden attacks on humans, hydrophobia symptoms, and a history of being bitten by another animal without having received rabies vaccination, the dog should be quarantined for further diagnosis.

Pathogenic diagnosis: Brain tissue from the suspect animal is examined through tissue sections or virus isolation tests. This is an essential method for confirming rabies.

Rabies Prevention and Control Measures:

Prevention: All dogs over three months old must be vaccinated with rabies vaccine at least once to effectively prevent the spread of the virus in society. Rabies vaccines include single rabies virus vaccines and multivalent vaccines that include rabies virus. The multivalent vaccine can provide immunity against other infectious diseases.

Rabies vaccine is only used for the preventive injection in healthy dogs and cannot be used for the prevention and treatment of dogs with active virus infections or pregnant dogs.

Treatment: There is no treatment for rabies in infected dogs. If rabies occurs, it should be reported immediately to the relevant animal husbandry and veterinary administrative authorities, and the affected area should be sealed off, quarantined, and disinfected.

For more information on the symptoms and prevention methods of rabies in Shih Tzus, as well as other petrelated knowledge, visit the "Dog Virus Transmission Category."