Canine distemper is a highly contagious infectious disease that threatens dogs the most. The causative agent of canine distemper is Paramyxoviridae and Morbillivirus. At present, there is only one serotype, which can infect a variety of cells and tissues. However, lymphocytes and epithelial cells have the strongest affinity, which seriously damages the body’s cellular immunity and humoral immunity. Susceptible animals are mainly a variety of canidae, mustelidae and raccoon animals, which are mainly infected through the respiratory tract, followed by the digestive tract, regardless of age, sex or breed. But,within one year of age,especially unimmunized puppies aged 2-6 months are most susceptible after the disappearance of maternal antibodies,often forming litters, and the mortality rate of infected puppies is as high as 90%. At the beginning of the infectious disease, there will be biphasic body temperature rise, serous or purulent secretions from the eyes and nose, respiratory tract and gastrointestinal infection symptoms, and neurological symptoms such as muscle twitching or paralysis in the middle and late stages.
In this article, the clinical diagnosis and treatment of canine distemper cases are sorted out as follows:
1: Case information
3.Years old: 3 months
5.Visit time: August 2021
2: Medical history investigation
1.Visiting questions: cough, fever, runny nose, dandruff on the body
2.Main statement: One week after purchasing the dog, the dog has not been vaccinated or dewormed. On the day of bringing the dog home, the owner found dander on the dog and gave it a bath. Afterwards, the dog had a runny nose and sneezing, thinking it was a cold. The owner gave the dog cephalosporins for humans, but it did not improve. The dog’s symptoms further developed into cough, sputum, and purulent nasal discharge. Today, the skin was palpated with fever, lack of energy and appetite, and then the owner brought the dog to see the doctor.
3: Physical examination
1. Overall inspection
BCS: 4/9, good body condition, rough fur, dander, normal bone development, mild dehydration.
2. General inspection
BW: 3.5KG T: 41℃ HR: 140/MIN RR: 40/MIN
3. System check
Auscultatory arrhythmia, pulmonary crackles, and induced cough were positive
4. Laboratory examination
Inspection items: canine distemper (CDV) antigen, small coronary double (CCPV) antigen, blood routine, acute reaction protein
Canine distemper antigen detection
Canine parvocoronary double antigen test
Acute response protein
The canine distemper antigen was strongly positive, and the blood routine and acute reaction protein indicated severe infection. The direction of diagnosis was canine distemper virus infection and pneumonia. Further imaging was recommended to confirm the condition of the lungs (not performed due to cost issues).
4: Diagnosis and treatment
Diagnosis: Canine distemper infection, pneumonia
1. Canine hyperimmune serum 3.5ML SC once a day for 5 consecutive days
2. Canine interferon 200U SC once a day for five consecutive days
3. Tilidine 0.35ML SC once a day (measure body temperature daily, no need to use if there is no fever)
4. Ceftriaxone 0.4ML +0.9%NACL100ml IV intravenous infusion at a rate of 15/H
5. Multivitamin B0.35ML+LRS 100ML IV intravenous infusion at a rate of 15/H
6. Energy group + 5%GS50ML IV intravenous infusion at a speed of 15/H
7. Ribavirin 0.35ML SC once a day for five consecutive days
8. Maxing Shigan Oral Liquid PO 2-4 times a day, 4ML each time
9. Doxycycline tablets PO once a day, 1/2 tablet each time
10. Nutritious and blood-enriching ointment, soothing and enhancing body resistance at the same time
11. Normal saline 20ML nebulized once a day
5: Matters needing attention
1. The mortality rate of canine distemper infectious disease is as high as 80% under the condition of best treatment, and the treatment cycle is long and the cost is relatively high. It is necessary to communicate well in advance to avoid disputes.
2. During the hospitalization period, separate isolation treatment is required, and the secretions from the mouth, nose and eyes of the dog should be cleaned up in time. Nursing staff need to do a good job of disinfection to avoid cross-infection in the hospital.
3. During the treatment period, body temperature, changes in eye and nose secretions, nose mirrors, foot pads, and neurological symptoms need to be checked daily, and medication needs to be adjusted according to these.
4. During the treatment, it is necessary to observe whether there are more symptoms than before admission, such as vomiting and diarrhea.
5. The owner does not recommend raising new dogs within half a year
Picture of discharge from nose and eyes
Picture of playing on the ground after being discharged from the hospital
After one week of medication, the pneumonia condition improved significantly, the mental appetite was normal, and there was no fever. The owner asked to be discharged from the hospital for observation. Eye secretions and coughing began to appear on the 3rd day after discharge home. On the 6th day, fever appeared again with neurological symptoms. We recommend that the owner bring the dog back to the clinic for follow-up consultation, and use nerve repair and regeneration drugs and symptomatic treatment. The owner gave up the treatment because the cure rate was too low and the cost was too high, the treatment cycle could not be determined, and the prognosis could not be known.
7: Disease pathogenesis and prevention
Canine distemper virus disease is the most harmful type of disease to dogs. The nasal fluid of sick dogs and infected dogs contains a large amount of viruses, and their tears, blood, urine, feces and exhaled gas also contain viruses. It is mainly transmitted through air and droplets, causing pollution of food, drinking water, supplies and surrounding air, etc., and is highly contagious. Canines are susceptible regardless of sex or age, but the mortality rate of young dogs is extremely high after infection. The incubation period of the disease is 3 to 14 days. The body temperature of most sick dogs rises to 39.8-41°C on the 4th or 5th day after infection, which lasts for 1-2 days, followed by a remission period of 2-3 days, and then rises again. It is a typical biphasic fever performance of canine distemper. With the rise of body temperature and the destruction of the immune system, the sick dog is depressed, loses appetite, moist eyes, tearing, coughing, continuous development will turn into mucus purulent secretions, and rough breath sounds on auscultation of the larynx, trachea and lungs. Then it develops into bronchial pneumonia or fibrinous pneumonia, dry nose, and hair loss around the eyes due to secretions from the eyes for a long time. A small number of dogs also have gastrointestinal symptoms, vomiting or blood in the stool, followed by dehydration. After 2 to 3 weeks of onset, most of the dogs will develop neurological symptoms, such as twitching of lips, eyelids, and ears, circling, rolling, paroxysmal twitching of limbs, or ataxia. When convulsions occur, it is highly suggested that the treatment is of little significance and the prognosis is poor. If you survive the treatment as soon as possible, you will be accompanied by sequelae of limb convulsions for life.
Prevention: At present, the most effective way to prevent this disease is to inject vaccines. The officially sold vaccines that can prevent canine distemper in the domestic market include VANGUARD® PLUS 5-CVL or Nobivac® Puppy DP. Puppies need to be vaccinated against infectious diseases three times for the first immunization, starting at the age of 2 months, and vaccinating once every 21 days. With the improvement of people’s living standards, the awareness of dog disease prevention has increased. Under the premise that prevention is better than cure, most owners can accept regular vaccination and good habits of deworming, which also greatly reduces the infection of infectious diseases and the opportunities for dissemination. Avoid contact with dogs that seem to have obvious respiratory symptoms when going out for a walk. During spring and autumn and other canine viral disease flu seasons, pay attention to temperature differences and enhance the dog’s body resistance, which can also reduce the chance of dog illness.