It’s never fun when you notice your puppy is feeling under the weather. Young puppies are particularly susceptible to illness because their immune systems are not fully developed.

There are a number of different ailments that can affect young dogs, and it’s important to know the symptoms of each so you know what requires immediate treatment and what doesn’t. These four ailments are particularly common in newly adopted puppies, so keep an eye out for their symptoms and alert your vet if anything seems amiss.

1. Kennel cough

If you’ve noticed that your puppy is making constant coughing noises, then this could be a sign of kennel cough. This bacterial infection is quite common in shelters and kennels because it can spread through the air or on shared surfaces and bowls.

A runny nose, discharge from the eyes and frequent sneezing can also be symptoms of kennel cough. Although this infection is usually mild in adult dogs, kennel cough can result in pneumonia in young puppies, so it is best to treat the condition as soon as possible.

Kennel cough is something that should be diagnosed and treated by your pet’s veterinarian. Usually, treatment involves antibiotics and other types of medication. One of the best ways to prevent your animal from getting kennel cough is by scheduling a vaccine for the condition.

2. Parvo

Parvo is another ailment that affects many puppies and can be highly contagious. Caused by the canine parvovirus, parvo can harm the bone marrow and intestinal tracts of infected dogs. Symptoms of this condition often include vomiting, diarrhea, weight loss, dehydration and more. While some dogs recover from parvo, it can be deadly—especially in young dogs.

As with kennel cough, the best way to prevent your puppy from getting parvo is to have them vaccinated. The parvovirus vaccine should be scheduled when your dog is around six to eight weeks old. A booster shot is typically administered yearly.

3. Parasites

There are many parasites that can infect your puppy and cause them extreme discomfort. Serious cases of parasites may cause diarrhea, vomiting and anorexia. In some cases, pets with an extreme parasite infection may not be able to recover. Fortunately, this is rare; most puppies will be just fine after treatment. This is why it’s important to make sure your dog is taking all the right medications and is staying in a clean environment.

Parasites can be internal or external. One of the most well-known internal parasites is heartworm, which can eventually cause respiratory damage and heart failure. Symptoms of heartworm include decreased appetite, tiredness, coughing and weight loss. Preventing heartworm is much easier than treating it in dogs, so ask your vet about heartworm prevention medication early on.

There are also internal parasites that can infect your puppy’s gastrointestinal system, including hookworms, tapeworms and whipworms. The types of parasites will make their home within your dog’s intestines and feed off blood of nutrients. Sometimes, these worms can be spotted in your pet’s feces, but other symptoms include lethargy, diarrhea and a ravenous appetite. Intestinal worms can usually be remedied with a deworming product.

Parasites can also infect your dog’s skin. Common skin parasites include fleas and ticks, which often cause itchiness and skin inflammation. These parasites can be prevented by purchasing a high-quality flea and tick medication. Keeping your dog out of areas where ticks are prevalent can also help prevent them from contracting diseases like Lyme disease or Rocky Mountain spotted fever.

4. Distemper

Distemper is another disease that features symptoms like coughing and lethargy. In most cases of distemper, your puppy will contract a fever and may have a loss of appetite. Like parvo, distemper can be fatal and is highly contagious.

Since there is no cure for distemper, it’s best to prevent your puppy from contracting it in the first place. The best way to prevent distemper is to make sure your puppy gets the distemper vaccination. This is one of the core vaccines your vet will recommend when your puppy is six to eight weeks old. You should also be sure to keep your dog away from any other dogs that may not be vaccinated.

Keep your puppy healthy and strong

While each these ailments are scary and could cause major harm to your furry friend, they’re all easily preventable. Make sure to follow the instructions given to you by your veterinarian and bolster their immune system from an early age to ensure they avoid serious illness and grow up happy and healthy.