Distemper virus in dogs, a condition that vets routinely vaccinate for. However, it doesn’t hit the headlines as much as some of the other doggy diseases like parvovirus and leptospirosis. Does this mean that it’s no longer a threat in the UK? Should we even bother to vaccinate against distemper virus anymore? 

The short answer is, yes, we definitely should! In this article, we’re going to explore distemper in more detail as well as discuss the importance of preventative medicine. 

What is distemper in dogs?

Distemper virus was once extremely common in the UK. This infectious illness affects several organs in the body including the digestive tract, lungs, heart, immune system and brain. This means it can cause a wide range of serious symptoms and can be fatal in up to 50% of cases, though some studies report higher than this. In years gone by, outbreaks would occur frequently resulting in the death of many dogs. 

The virus is easily spread, making it extremely contagious. It is shed from the respiratory tract of affected dogs, as well as in urine and faeces. It can be contracted through direct contact with an infected dog, who may continue to shed the virus for several months after recovery. Contacting an infected environment can also spread disease, but this is less likely as the virus is not as stable outside of a host.

Distemper is a paramyxovirus, which is closely related to the measles virus in humans. 

What are the signs of distemper in dogs?

The initial symptoms of distemper can vary between individuals. Most dogs will have a watery to pus-like discharge from their eyes. This is followed by a fever, reduced appetite and clear nasal discharge, though it can take 3-6 days for this to develop. 

A dog affected by distemper may have the following symptoms initially – 

  • Fever
  • Clear nasal discharge
  • Discharge from the eyes (pus-like)
  • Reduced appetite
  • Lethargy
  • Coughing
  • Vomiting
  • Diarrhoea
  • Skin infections
  • Inflammation in the central nervous system (brain and spinal cord)

If a dog survives this stage of the disease, it may develop thickening of their paw pads and nose. This hyperkeratosis gives distemper virus its common nickname of ‘hard-pad disease’. The pads may be enlarged, tender, and hardened. 

Dogs that contract distemper virus are also vulnerable to secondary bacteria infections. This can lead to complicating issues like pneumonia (severe chest infection) and intestinal problems. As the disease progresses, the dog’s central nervous system becomes more affected which can lead to signs such as – 

  • A head tilt
  • Circling
  • Loss of balance
  • Head-pressing (pressing their head against a wall)
  • Paralysis
  • Seizures
  • Death

Dogs that manage to survive this stage of the disease may have irreversible damage to their nervous system.

How is distemper virus treated in dogs?

Sadly, there is no cure for distemper virus. There are no anti-viral medications currently licensed for treating this infection. To give your pet the best chance of survival they will need to be treated promptly. Hospitalisation for nursing care and supportive treatment is required, which can include –

  • Intravenous fluid therapy – fluids via a drip to correct dehydration and support blood pressure
  • Antibiotics – to treat any secondary bacterial infections, or stop them from occurring
  • Anti-nausea medication – to stop vomiting and improve feelings of nausea
  • Anti-seizure medication – this will be needed if your dog is having seizure episodes
  • Nutritional support – some dogs may require assisted feeding if they are unable to eat enough themselves

During this time, they will need to be kept apart from other dogs with strict barrier nursing in place. This is important to stop the disease from infecting others.

Recovery will depend on how severely the dog is affected and how well their immune system is functioning. Some dogs may improve by 10 days, whereas others can have neurological symptoms for many weeks or months afterwards. Understandably some owners may not be able to afford this level of veterinary care, plus long-term prognosis can be poor in severely affected animals. Therefore, euthanasia may also be a valid option for dogs infected with distemper virus. 

How is distemper virus prevented?

Vaccination is the only way to protect your dog from distemper virus. Puppies can have a primary course of vaccinations from 6-8 weeks of age onwards. Your vet will boost their immunity again at around a year of age, and then once every 3 years ongoing, based on manufacturer guidelines and consensus from the World Small Animal Veterinary Association (WSAVA). The WSAVA class distemper as a ‘core’ vaccination meaning that all dogs should have it.

Some owners decide to tire test their dogs to see if they have protective levels of distemper virus in their system. This blood sample informs your vet whether your dog requires a distemper booster vaccination or not. However other recommended vaccinations like leptospirosis and kennel cough cannot be titre tested for and still require annual injections. So as this means a once-a-year trip to the vet for a vaccination and check-up anyway, most owners just continue to vaccinate every 3 years as part of these yearly booster vaccinations. 

Speak to your vet if you have any questions about titre testing or vaccination timings. 

How prevalent is distemper virus?

Outbreaks used to be very common in the UK, but thanks to vaccinations these occur far less frequently. However, cases in mainland Europe are still very common and with a rise in imported animals there is a real risk of distemper cases increasing here.

Distemper can also infect wildlife such as foxes, ferrets, otters and badgers, as well as seals and zoo animals. Dogs are the main reservoir for distemper, but as we have learned from outbreaks such as COVID-19, viruses and the way they spread constantly evolve. 

Sporadic cases are regularly being reported in the UK, so it is definitely not extinct.

Do I still need to vaccinate my dog for distemper virus?

The short answer is, yes! Routine vaccination has been great at driving down the number of distemper cases we see in the UK, but this doesn’t mean it has been eradicated altogether. 

This phenomenon is known as ‘herd immunity’. This describes when a significant amount of the population (or herd) is vaccinated against a disease, giving protection to those in the group that are not. Because so many dogs are vaccinated for distemper there are fewer infected animals around to spread disease, meaning that the small proportion of unvaccinated dogs are less at risk. But if the numbers of vaccinated dogs drop, we will start to see outbreaks again which will spread more easily through unprotected animals. 

We know that this is dangerous, and we have seen it play out in human disease. A decrease in uptake of the MMR vaccination (measles, mumps and rubella), has led to a spike in cases of measles in the UK. Health experts are constantly reminding people to stay up to date with their vaccinations, not only to protect themselves and their families but also to protect the wider population who may be too young to be vaccinated (very tiny babies) or who are immunocompromised. Sadly, many people have become complacent, not realising the long-term harm that these preventable diseases can cause. Unfounded claims about the risk of vaccination have also caused damage, with myths around autism in children unfortunately still circulating. 

We can see how damaging distemper can be… why are some owners not vaccinating?

The anti-vaccination movement is extremely dangerous in both human and veterinary medicine. Sadly, there has been a recent trend for turning down vaccinations for our canine companions, despite scientific evidence to back their use. 

According to the PDSA PAW report, 20% of owners report their dogs are unvaccinated with reasons cited such as –

  • Vaccinations are too expensive
  • Worried about side effects
  • Vaccinations are not necessary
  • Don’t know what vaccinations their pet has already had

As we have already discussed, vaccinations are definitely necessary. If you are unclear about what vaccinations your pet has had then speak to your vet. If your pet has a vague medical history, then it may be safest to revaccinate them as a precaution.

Side effects can occur with any medication, but the risks with vaccinations are very low. These products have been rigorously safety tested and are used in hundreds of animals every day. Your vet will be happy to discuss this with you and hopefully alleviate your concerns. 

The cost-of-living crisis has meant that some owners are struggling to afford veterinary care for their pets. This may be one reason for vaccinations not being done. Many practices have health care plans in place to help owners budget for their dog’s preventative treatments as well as providing discounts. Charity help may also be available to owners who meet their qualifying criteria. Don’t be afraid to reach out to see what is available. 

Summary

Distemper is much less common in the UK than it has been in previous years, thanks to the success of routine vaccination. However, sporadic cases are still reported meaning that it is definitely not extinct. Imported animals and the risk of a decline in vaccination uptake mean that outbreaks could start occurring again. Herd immunity only works if the majority of the canine population is vaccinated.

 If you have any concerns about vaccinations or distemper, then contact your vet for more advice. 

FAQs

What dogs are most at risk from distemper virus?

Distemper can affect any dog, but unvaccinated dogs and young puppies (less than 4 months of age) are most at risk.  

Can humans catch canine distemper virus?

No canine distemper virus is not infectious to humans. However, measles is a virus that is closely related to distemper. Thankfully we can protect ourselves against measles through routine vaccinations. 

Is a distemper shot necessary for dogs?

The World Small Animal Veterinary Association (WSAVA) class distemper as a ‘core’ vaccination. This means that it is recommended for all dogs. Distemper is a highly infectious virus that can be fatal, so vaccination is the best way to protect our dogs.