Common puppy illnesses and what to do about them

From creating a new routine to training your puppy, there’s a lot to think about as you get used to life with your new family member. It’s also important to know which common illnesses can affect puppies, and what to do if you notice any symptoms.


As puppies grow up and start to explore their new environment, they can be exposed to a lot of diseases that can prove dangerous before your pup is fully vaccinated. Knowing the warning signs for the most common puppy illnesses can help you keep your new friend as healthy as possible. 

Caused by a range of viruses or bacteria, this airway infection is most common in places where a lot of dogs mix, like boarding or day care centres. Kennel cough spreads through the air as well as direct contact with infected dogs, and can remain in the environment for several weeks. 

Symptoms: A dry, hacking cough. In puppies this is often accompanied by a high temperature, lethargy and reduced appetite.

Action: Request an appointment with your vet. Many cases clear up on their own, but your puppy may require antibiotics or anti-inflammatories. Infected puppies will be contagious so avoid contact with other dogs.

This highly contagious and relatively common disease is caused by a virus that spreads through direct and indirect contact. Parvovirus can survive in the environment for up to a year and attacks a puppy’s intestines. Unvaccinated puppies, under six months, are particularly susceptible. 

Symptoms: Vomiting, diarrhoea (often bloody and very smelly), fever, lethargy, weight loss, dehydration, weakness, and a depressed demeanour. 

Action: Immediate veterinary attention. There is no cure, so supportive care including fluids and intensive nursing care may be offered. Infected puppies will be very contagious so avoid contact with other dogs. Parvo can be a fatal illness, but quick veterinary care will improve chances of survival.

Canine distemper is now rare in the UK but is still sometimes seen in young, unvaccinated puppies. This virus spreads through the air, through bodily fluids and can also remain in the environment for a few hours, or longer in cold and wet weather.

Symptoms: Early signs include a runny nose and eyes, along with a cough, diarrhoea, fever, and lethargy. Later signs include thickened skin on the nose and paw pads along with tremors and fits.

Action: Immediate veterinary support. There is no cure, but your vet will provide supportive care depending on a puppy’s specific symptoms. Recovery rate can be low and many dogs that do recover may have relapses and require ongoing medical care.   

Also known as canine adenovirus or Rubarth’s Disease, this illness can be caught through direct or indirect contact with another infected dog. This virus affects the kidneys, eyes, lungs, heart, liver, blood and immune system.

Symptoms: Variable, depending on which organs have been affected. Mild cases can show lethargy, coughing, vomiting, diarrhoea, and reduced appetite. Severe cases may include high temperature and pale or yellow gums in addition to small red dots on the skin or gums.

Action: Immediate veterinary support, which will vary depending on your puppy’s symptoms. Puppies with mild symptoms that receive quick treatment have a good chance of recovery. The prognosis for puppies with severe symptoms or that receive delayed treatment is not as good. 

Caused by bacteria spread through either infected water, or contact with infected animals or their urine (including other dogs, mice, rats and cows). Leptospirosis can cause damage to the kidneys and liver. This illness can be caught by humans, and is often called Weil’s Disease. Leptospirosis can survive in the environment for several months.  

Symptoms: Extremely variable, but can include fever, jaundice, weakness, and a reduced appetite. If your unvaccinated puppy has been swimming, been in contact with rodents, or spends time on a farm, the risk is increased. 

Action: Supportive veterinary care which may include antibiotics and fluids. This is a serious disease.  

Many of the most common puppy illnesses we’ve covered below can be prevented by following a vaccination schedule as recommended by your vet. It’s also a good idea to give your puppy a regular, at-home health check in between their routine vet visits. 

Before your puppy’s vaccinations are complete, protect them from illness by keeping them at home. They can explore your garden as long as you haven’t had recent visits from unvaccinated dogs. If you do take your puppy out in public, it’s better to carry them rather than allow them to walk on the ground, where they’re at higher risk of picking up an illness. 

You know your puppy best, so if their symptoms don’t match any of those we’ve covered above but you’re still worried, contact your vet for more advice. 

At Petplan, 90% of insurance claims are due to illness. In addition to knowing what signs to look out for, making sure your puppy is both vaccinated and insured can help give you peace of mind if your puppy does get ill, leaving you more time to enjoy being together.


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