Canine distemper

The origin of the word distemper is from Middle English , 'to upset the balance of the humors', which is from Old French , 'to disturb', which is from Vulgar Latin , 'to not mix properly'. ==History==

In Europe, the first report of CDV occurred in Spain in 1761. Carré's findings were disputed by researchers in England until 1926, when Patrick Laidlaw and G.W. Dunkin confirmed that the disease was, in fact, caused by a virus. In 1923 and 1924, Puntoni published two articles in which he added formalin to brain tissue from infected dogs to create a vaccine that successfully prevented the disease in healthy dogs. The domestic dog has largely been responsible for introducing canine distemper to previously unexposed wildlife and now causes a serious conservation threat to many species of carnivores and some species of marsupials. The virus contributed to the near-extinction of the black-footed ferret. It also may have played a considerable role in the extinction of the thylacine (Tasmanian tiger) and recurrently causes mortality among African wild dogs. In 2026, 72 captive tigers died from canine distemper at two nature parks in Chiang Mai Province, Thailand. The disease has also mutated into the phocine distemper virus, which affects seals. ==Clinical signs==

In dogs, signs of CDV vary widely, from no signs to mild respiratory signs indistinguishable from kennel cough to severe pneumonia with vomiting, bloody diarrhea, and death. Commonly observed signs are a runny nose, vomiting and diarrhea, dehydration, excessive salivation, coughing and/or labored breathing, loss of appetite, and weight loss. If neurological signs develop, incontinence may ensue. Central nervous system signs include a localized involuntary twitching of muscles or groups of muscles, seizures with salivation, and jaw movements commonly described as "chewing-gum fits," or more appropriately as "distemper myoclonus." As the condition progresses, the seizures worsen and progress to grand mal convulsions, followed by the death of the animal. The animal may also show signs of sensitivity to light, incoordination, circling, increased sensitivity to sensory stimuli such as pain or touch, and deterioration of motor capabilities. Less commonly, they may lead to blindness and paralysis. The length of the systemic disease may be as short as 10 days, or the start of neurological signs may not occur until several weeks or months later. Those few that survive usually have a small tic or twitch of varying degrees of severity. With time, this tic usually diminishes somewhat in its severity. in advanced stage of infection. Life-threatening complications can include nervous-system degeneration. Dogs that have been infected with distemper can have a progressive deterioration of mental abilities and motor skills. With time, the dog can develop seizures, paralysis, a reduction in sight, and incoordination. These dogs are usually humanely euthanized because of the immense pain and suffering they face. ==Virology==

Distemper is caused by a single-stranded RNA virus of the family Paramyxoviridae, and is a very close relative of the viruses of the same genus that cause measles in humans and rinderpest in animals. Genetic diversity Geographically distinct lineages of the canine distemper virus are genetically diverse. This diversity arises from mutation and, when two genetically distinct viruses infect the same cell, from homologous recombination. Host range Distemper, or hardpad disease in canines, affects animals in the following families and species: • Ailuridae (red panda) • Canidae (dog, fox, wolf, Chinese raccoon dog) • Elephantidae (Asian elephant) • Felidae (large cats, Both large and domestic cats are now known to be capable of infection, usually through close housing with dogs or possibly blood transfusion from infected cats, ==Mechanism==

The canine distemper virus affects nearly all body systems. Puppies from 3–6 months old are particularly susceptible. CDV spreads through aerosol droplets and through contact with infected bodily fluids, including nasal and ocular secretions, feces, and urine, 6 to 22 days after exposure. It can also be spread by food and water contaminated with these fluids. The time between infection and disease is 14 to 18 days, although a fever can appear from 3 to 6 days after infection. The canine distemper virus tends to direct its infection toward the lymphoid, epithelial, and nervous tissues. The virus initially replicates in the lymphatic tissue of the respiratory tract. The virus then enters the blood stream and infects the respiratory, gastrointestinal, urogenital, epithelial, and central nervous systems, as well as optic nerves. ==Diagnosis==

B. Viral inclusion bodies The above signs, especially fever, respiratory signs, neurological signs, and thickened footpads, occurring in unvaccinated dogs strongly indicate CDV. However, several febrile diseases match many of the signs of the disease and only recently has distinguishing between canine hepatitis, herpes virus, parainfluenza, and leptospirosis been possible. ==Prevention==

A number of vaccines against CDV exist for dogs (ATCvet code: and combinations) and domestic ferrets (), which in many jurisdictions are mandatory for pets. Infected animals should be quarantined from other dogs for several months owing to the length of time the animal may shed the virus. It, along with other labile viruses, can also persist longer in serum and tissue debris. ==Treatment==

No specific treatment for the CDV is known. As with measles, the treatment is symptomatic and supportive. ==Outcome==

The mortality rate of CDV largely depends on the immune status of the infected dogs. Puppies experience the highest mortality rate, where complications such as pneumonia and encephalitis are more common. Around 15% of canine inflammatory central nervous system diseases are a result of CDV. ==Epidemiology==

The prevalence of canine distemper in the community has decreased dramatically due to the availability of vaccinations. However, the disease continues to spread among unvaccinated populations, such as those in animal shelters and pet stores. This provides a great threat to both the rural and urban communities throughout the United States, affecting both shelter and domestic canines. Despite the effectiveness of the vaccination, outbreaks of this disease continue to occur nationally. In April 2011, the Arizona Humane Society released a valley-wide pet health alert throughout Phoenix, Arizona. Outbreaks of canine distemper continue to occur throughout the United States and elsewhere and are caused by many factors, including proximity to wild animals and lack of vaccinated animals. This problem is even greater within areas such as Arizona, owing to the vast amount of rural land. An unaccountable number of strays that lack vaccinations reside in these areas, so they are more susceptible to diseases such as canine distemper. These strays act as a reservoir for the virus, spreading it throughout the surrounding area, including urban areas. Puppies and dogs that have not received their shots can then be infected in a place where many dogs interact, such as a dog park. ==References==