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Puppy illnesses to watch out for!

: McKenzie Lowe, for TAPACT

Bringing home a new puppy is one of life’s most exciting experiences! Puppies are little angels, full of affection and curiosity. But, it is important to make sure they are happy and healthy.  

Puppies are more vulnerable to illness than adult dogs. Unfortunately, the dangers increase for puppies if they are purchased from an unethical breeder, like a puppy mill or those who sell puppies at the US-Mexico border. 

Many of the puppies sold at the border are taken from the streets. They are often separated from their mothers too early and kept in less-than-ideal conditions. These issues combine to make the puppies extra-susceptible to many common illnesses.

Here is a list of some prevalent puppy illnesses to keep an eye out for. Many of the puppies sold by street vendors have one or more of these diseases. Please DO NOT buy a puppy from them. 

If you have a puppy that is experiencing any of these symptoms, please contact your veterinarian immediately.


Canine parvovirus, also known as parvo, is a very contagious virus that causes lethargy, loss of appetite, pain, and bloating. It also causes vomiting and bloody diarrhea. It can affect any dog, but puppies younger than four months who haven’t received vaccinations are most at-risk.

There is no known treatment for parvo. All you can do is make sure a sick puppy is getting hydrated, replacing electrolytes, and getting protein and fluids. Prevention is key – puppies should receive a vaccine and get re-vaccinated every year.

It is also important to isolate a sick puppy. Parvovirus is highly contagious because it is heat-resistant. It can easily be spread to other puppies through shared water, food, human clothing, or feces.


Distemper is a disease that attacks the respiratory, gastro-intestinal, and nervous system in dogs. It is spread through airborne particles or contact with wildlife; many other species are also vulnerable to the virus. Distemper is a very serious condition and is often fatal. Dogs that recover often have lifelong complications. 

There is no known treatment. It is important to get dogs vaccinated for prevention. Puppies under four months old and unvaccinated dogs are most at-risk.

Symptoms of distemper include watery pus from their eyes, nasal discharge, coughing, and lethargy. Symptoms can get worse and turn into vomiting, seizures, and paralysis.

Heartworm Disease:

Heartworms are a parasite that can affect dogs, cats, and many species of wildlife. The worms can only be introduced by mosquito bites, and are not contagious between animals. 

Symptoms of heartworm disease include coughing and lethargy. If untreated, heartworms can be fatal because they will reproduce and cause damage to the dog’s heart and lungs. 

Heartworms can be prevented with regular medication. Annual heartworm checks are also recommended.

If a dog does get heartworms, there are medications available to kill the parasite and manage the inflammatory response. The dog will require a lot of rest to have a chance to heal properly. Surgery is sometimes necessary for removal, but it is a complicated and high-risk procedure.


Fleas are a common parasite. They can transfer onto other dogs, humans, and fabric materials. Symptoms of flea bites include redness, open sores, and severe itchiness. 

There are preventative medications that should be given monthly. If a dog gets fleas, their vet can prescribe different treatments like topical ointments or chewable pills. Flea eggs can remain on clothing and furniture for weeks – so it is very important to clean and wash thoroughly.


Ticks are another common and preventable parasite. Ticks attach to skin and gorge on blood. They can transmit serious illnesses like Lyme disease, which is why prevention is very important. Usually, the same medicine covers flea and tick prevention and will be given monthly.

Symptoms of a tick bite include skin irritation, and can cause anemia in severe cases. They often latch on around the ears and neck, or in areas with skin folds. It is important to check for ticks after outdoor activities and to remove them as soon as possible.

Demodectic Mange:

Mange is caused by microscopic mites. Mothers can pass these mites to her puppies, but they are not contagious to other dogs. Demodectic Mange can signify a greater underlying health issue, so it is important to have a dog with mange evaluated.

Symptoms of demodectic mange include scaly and red patches of skin around their eyes, mouth, and legs. Bacterial infections are also common in puppies. Vets can create a treatment plan and determine if the dog has any other health issues to be concerned about.

Sarcoptic Mange:

Also known as scabies, sarcoptic mange is caused by another type of mite. They are highly contagious and can be spread through contact with infested animals, shared bedding, and grooming tools. Humans can also develop symptoms from contact.

Scabies mites burrow into the dog’s skin and cause intense burning and itching. This can lead to hair loss, rashes, crusting, and skin irritation. Treatment includes medication to kill the mites and to soothe their skin issues. It will also be necessary to deep clean their living space.


Giardia is an intestinal infection that affects dogs and people. It is caused by a single cell parasite. Many dogs can possess Giardia without any symptoms. It can be passed through their stool, and then passed to other dogs when they sniff it. It is common in high-activity locations like kennels and dog parks. 

Puppies and older dogs are most at-risk, because they often develop severe diarrhea and can need clinical intervention.  The most common symptoms are diarrhea and persistent weight loss. If a puppy has a severe case, they can be treated with a special, highly-digestible diet and two-four weeks of rest.


It can be extremely hard to think about sick puppies and the conditions that make it worse for them. But, it is important to be educated on these issues, so we can recognize the symptoms and help to treat them. 

Next time you want to add a bundle of joy to your family and bring home a puppy, please consider adoption. Shelters and rescues will get treatment for any issues that puppies face, and they assist with necessary vaccines.

And please share this list if you have any friends or family that are considering buying a puppy from a street vendor, puppy mill, or online marketplace. Make sure they are aware of the dangers!