12 common bacterial infections in dogs and how to spot them

Wouldn’t it be great if dogs could talk? It’d be interesting to hear their take on the world. But also, as pawrents, it’d save us a lot of stress trying to figure out if something’s wrong. They could just tell us that their new food doesn’t sit right or that something’s bothering them.

But sadly, they can’t. So that means we have to scrutinise every single aspect of their lives and bodies. Their behaviour, their eyes, teeth, skin, paws, and even their poop. It’s not the most fun part of having a doggo, but hey, someone’s gotta do it. 

And to make matters even more difficult, it isn’t just allergies, intolerances, and joint problems we have to look out for; there are plenty of other health issues, such as bacterial infections in dogs. Worse still, some bacterial infections in dogs can be fatal if left untreated.

As with humans, some are more common than others. The good news is we can learn about these common infections, making them easier to treat. So what are the most common bacterial infections in dogs and how can you spot them? 


Babesiosis is a common bacterial infection in dogs that’s usually transmitted through a tick bite. But there are other methods of transmission, such as through a dog bite or blood transfusion. It can also be passed from mother to pup through the placenta. Thankfully, these ticks aren’t the most common in the UK, but they’re still out there. And, unfortunately, babesiosis can be fatal, so it’s important to know the signs.

This nasty infection attacks your dog’s red blood cells, which are as vital for our dogs as they are for us. Without enough red blood cells, your dog could become anaemic. 

Symptoms: Since this infection attacks their red blood cells, your pup will likely be lethargic and may even collapse. They may also have blood in their urine, a fever, jaundice, or a cough. Other symptoms to look out for include pale gums and a loss of appetite. 

Giardiasis or giardia

This bacteria is commonly transmitted through contaminated drinking water, but can also be contracted through consuming the poo of an infected animal, such as a cat or another dog. Once ingested, giardiasis infects the small intestine and multiplies. There are two different forms of this parasite, but they both cause similar symptoms. 

Symptoms: As this infection is based in the small intestine, symptoms include severe diarrhoea, vomiting, and weight loss. Other symptoms include an unkempt, dry coat and dehydration. Another point to note is that symptoms of giardiasis are easier to identify in puppies compared to older dogs.

If you recently brought home a new pupper from the kennel, you might want to keep an eye out, as it’s more common in these situations due to close living conditions.


This infection is based in the digestive system. It’s transmitted through eating raw meat, or by ingesting or coming in contact with infected food, poop, or water. Campylobacter is common in puppies under six months old as their immune system hasn’t fully developed yet. But this doesn’t mean your adult doggo is immune. 

To make matters worse, it’s possible for humans to contract it and it can even cause miscarriage in pregnant women. So if you think your pup might have it, be extremely careful and practise proper hygiene. 

Symptoms: Key symptoms you should look for include watery or mucousy diarrhoea, tummy cramping or pain, fever, and lethargy. Diarrhoea can last a week or longer and will often suddenly appear again when it seems your doggo has recovered.

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Kennel cough

This disease is a highly infectious bronchitis-like infection that affects a dog’s respiratory system, causing a cough. Kennel cough is so infectious that many kennels vaccinate their pups against it. But frustratingly, kennel cough – like the flu in humans – is always mutating, so vaccination isn’t always effective. 

There’s no specific parasite that leads to kennel cough. Rather, it’s typically a combination of different bacteria and viruses. While annoying for your doggo, kennel cough is unlikely to be dangerous. But in puppies, older dogs, or pups with existing health problems, it could develop into pneumonia. 

Symptoms: As the name suggests, the primary symptom is a forced, hacking cough. Identifying this in a pup can be tricky if you haven’t heard it before. Listen to the sound they’re making. If it sounds like there’s something stuck in their throat, it could be kennel cough. It’ll sound dry and rough, and might be followed by a gagging sound. It may also look like they’re swallowing or producing mucus.

Aside from the cough, there aren’t many other symptoms. Doggo’s can appear perfectly healthy except for the cough and possibly a runny nose, discharge from their eyes, and sneezing. 


Sandflies are the main culprits in leishmaniasis as they carry this parasitic infection. It’s extremely rare in the UK, but it made our list as, if you ever plan on taking your pup travelling with you, they could contract it abroad. And it’s important to note that although humans can contract it too, there has never been a reported case of someone catching it from a doggo.

The bacteria will affect either the skin or internal organs, such as the kidneys, liver, or spleen. These two infections are completely different with varting symptoms, but are both caused by the same parasite.

Symptoms: Almost all dogs with this infection will have the kind that affects the organs. There are many scary symptoms to keep an eye out for, including severe weight loss, a lack of appetite, fever, vomiting, diarrhoea, weakness, exercise intolerance, nosebleeds, and bloody poop that looks dark and tar-like. 

Another fairly common symptom is swollen lymph nodes. You can find these in their neck, chest, armpits, groin, and behind their knees. Your pup may also have an enlarged spleen, and in males, their testicles may swell up.

If your pup develops the skin infection, symptoms include thickened, hardened muzzle and toe beans. And as this disease gets worse, the pigment of these tissues can fade away. They may also experience hair loss and develop a dull, brittle coat. 

Lyme disease

Lyme disease is one of the most common diseases transmitted by ticks. But only 5-10% of affected dogs display symptoms. If you like going out for walks in the woods, inspecting your pup for ticks, learning how to remove them, and investing in anti-tick products is a great idea to keep your doggo – and yourself – protected. 

Symptoms: Even when symptomless, Lyme disease can cause health problems, so prevention is better than cure. Symptoms to look out for include depression, fever, lethargy, loss of appetite, swollen lymph nodes, stiff walking, and what’s known as lameness. Lameness essentially means your pup is struggling to use some of their limbs. This is because Lyme disease causes inflammation of the joints. 

Left untreated, Lyme disease can damage the heart, kidneys, and nervous system. So if you think an affected tick has bitten your pooch, go straight to the vets.

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While more common in cats, toxoplasmosis can affect your dog too. And if they have a habit of munching down on cat poop, this is one to watch for. Toxoplasmosis is an infection of the digestive system that’s caused by eating infected cat poop, sniffing around in the soil around infected cat poop, eating contaminated raw or undercooked meat, or drinking water containing the parasite. 

A healthy doggo with a strong immune system typically won’t develop this infection. But if they have weakened immune system, they could fall victim. Puppies may also be vulnerable, as their immune system hasn’t fully developed yet.

Symptoms: If you think your pooch has developed this nasty infection, you might notice they’re experiencing severe digestive upset such as vomiting, frequent poops, and mushy, watery poops. They may also have a fever, cough, diarrhoea, and trouble breathing. Jaundice could be an issue, too, though this may be tricky to identify, especially if they have dark fur. But if you can’t find any indication on their skin, check their gums and eyes for the signature yellow pigmentation.

Paralysis and eye inflammation are common signs too. In the worst cases, it could lead to seizures and even be fatal. The symptoms for toxoplasmosis are so wide, affecting various parts of the body, which can make it tricky to diagnose. 


Yep, our fur babies can get salmonella just like us. Many assume that dogs have a much stronger stomach and can handle eating foods we can’t. And while this is true for many dogs, it doesn’t mean they’re invincible. Even simple little mistakes can lead to your pup developing salmonella. 

For example, if you feed them wet food and forget to put the open tin in the fridge between meals. The same goes for raw food that isn’t stored at the correct temperature. But even just coming in contact with contaminated food, or the poop or saliva of another infected animal, could cause salmonella. 

Symptoms: Older doggos, those with weaker immune systems, and pups with other health problems such as cancer are more at risk of salmonella. Since they’re weaker, it can even be fatal. Common symptoms aren’t too dissimilar to ones we get. They include fever, fatigue, dehydration, loss of appetite, diarrhoea that might contain blood or mucus, and abdominal pain.

Staphylococcal (staph) infection

Staph infections are inflammatory skin conditions caused by the bacteria staphylococcus. All dogs (and humans) have staphylococcus living on their skin. It’s always there and doesn’t cause any harm, unless the skin is damaged or the pup has an underlying medical condition. That’s when it turns into an infection. 

This can easily develop when you have a doggo that excessively licks, chews, or scratches themselves. So pups with fleas or allergies are most at risk here. Older dogs are also more at risk since their immune system is weaker. 

Symptoms: If your pup licks themselves like there’s no tomorrow, you’ll want to familiarise yourself with the following symptoms. Red, inflamed skin, pus-filled lesions, patchy fur loss, crusty, peeling skin, and infections of the skin, eyes, ears, or respiratory system. 

Staph infections may not sound like a big deal. They only come from excessive licking, so surely they can’t be that bad, right? Not exactly. If left untreated, they can lead to blood poisoning and can even be fatal. Keep an eye on your pooch to make sure they aren’t putting themselves at risk of this infection. 

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In dogs, there are two types of this bacteria that can lead to an infection: clostridium perfringens and clostridium difficile. It’s suspected that up to 15-20% of diarrhoea cases in doggos are related to the bacteria clostridium perfringens. Both kinds spread through the intestinal tract and are contracted through infected dog poop or food. It can live in soil too.

Symptoms: A pup with clostridium may have symptoms such as diarrhoea that can become severe, abdominal cramps, vomiting, dehydration, fever, and lethargy. Symptoms can vary and sometimes there may not even be any at all as clostridium can be both chronic or severe.


Campylobacter, the bacteria that causes campylobacteriosis, is found naturally in the gut of healthy dogs. Around 49% of doggos carry this, and it’s more common in pups under six months old. The most frequent outcome is enteritis, which is inflammation of the small intestine.

If your pooch has a history of intestinal diseases and infections such as salmonella, they’re at higher risk of developing this bacterial infection. Puppies who live in crowded conditions such as kennels or poorly sanitised areas are at higher risk too. The same goes for those who are ill, pregnant, or under stress due to surgery. 

Symptoms: As this bacterial infection affects the small intestine, the main symptom is diarrhoea. But some dogs may also experience vomiting, fever, abdominal pain, weight loss, and black, tarry poops.


Like campylobacter, streptococcus exists naturally in a dog’s body. But every now and then, that bacteria can cause infections. If it does do this, it’s typically because the dog is young, old, or has a weakened immune system, which makes it easy for these bacteria to invade other areas of the body.

Symptoms: The symptoms vary a lot with this infection, so it can be a bit tricky to notice. But some common ones include:

  • Vomiting 
  • Lack of appetite 
  • Coughing 
  • Discharge from the nose
  • Inflammation and redness
  • Fever 
  • Weakness
  • Sores on the skin
  • Difficulty walking 
  • Lethargy 
  • Painful urination
  • Infected cuts
  • Infected ears, eyes, and skin
  • Disinterest in playing or exercise 
  • Urinary tract and respiratory infections 

It’s a lot, we know. That’s what can make identifying a problem so difficult. You might just think your pup is tired when really there’s something more sinister going on. 

There are different types of this infection too, affecting areas such as the sinuses, skin, urinary tract, throat, and respiratory system.

Us pawrents have a tendency to overreact to any symptoms our pups show. But even if you think you may be overreacting, speak to a vet. Even if it isn’t one of the infections listed here, it could be something else that’s equally damaging to their health. Or it could be nothing. Either way, it’s always better to be safe than sorry and vets know best.

We all want what’s best for our pups. And good health starts with good nutrition. Swagwags kibble contains high-quality, responsibly sourced protein. And with no nasties such as artificial colours, flavours, and dodgy cuts of “meat”, you can rest easy knowing your doggo is eating well. Find your pup’s new favourite flavour today.

If you’re ever concerned about potential allergies, take one of our sensitivity tests. It’s non-invasive and takes 5 minutes to do – a small price for perfect pup health!