Invisible Infections - Groomer to Groomer Magazine

But Why?

Invisible Infections

We’ve all heard the old saying, “What you don’t know won’t hurt you,” and we all know this isn’t really true. The same goes for what you don’t see. Sometimes the things that can be the most harmful are the ones that you cannot see with the naked eye. 

When we work with animals, there are many things that we can encounter without even knowing we’re encountering them. Keeping our tools, stations and hands clean are of utmost importance to keeping ourselves safe and free from hidden dangers that can come from working with animals. 

In the era of COVID–19, we’ve all become painfully aware of the dangers of environmental germs that can cause us harm, and keeping up with healthy hygiene habits such as hand washing has become key to staying safe and healthy. We’re more aware of the germs that can be passed from human to human, but why do we need to also worry about the dangers of germs passed from pets to humans?

The answer to that question is simple—we need to be careful because there are some commonly–seen infections that are passed from dogs and cats to humans more frequently than you might think. 


Every year, millions of people become infected with bacterial, fungal and parasitic infections from their pets, and pet groomers are part of that group. There’s no need to panic though; there are very simple ways to avoid becoming infected with these common infections by simply keeping your work environment clean, washing your hands when working with pets and sanitizing often. Let’s go over some of the most common infections people can acquire from pets and how to avoid becoming infected.

Campylobacter Bacteria

One of the most common bacterial infections seen in humans is caused by Campylobacter bacteria. Campylobacter bacteria affect more than two million people every year and are one of the main causes of diarrhea. These bacteria infect the gastrointestinal tract and cause diarrhea, cramps and fever, and most commonly affect babies, teens and young adults. 

These bacteria live in the intestines of both wild and domestic animals and are spread to humans when animal feces comes in contact with food or water, or direct contact with hands, which can inadvertently make its way into human systems. Once inside the human digestive tract, they affect the lining of the intestines. The bacteria can also be passed from human to human through diaper changing or poor hygiene. 

Symptoms start within seven days of infection and usually only last for one week. Most people with infections will recover on their own without medication, but in severe cases, antibiotics will be prescribed. Some complications from this infection are dehydration, severe cramping and, in rare cases, joint inflammation and Guillain–Barre syndrome, an uncommon autoimmune disorder. 


Toxocariasis is an infection caused by a type of worm that can live in the intestines of cats and dogs. While it is most common in young children and pet owners, anyone who comes in contact with pets can become infected. 

The infection occurs when eggs from the canine round worm Toxocara canis or the feline round worm Toxocara cati are present in cat or dog feces. The eggs can live for a long time in the soil of yards, parks or playgrounds and can be passed to people by swallowing the eggs through dirty food or dirty hands that come in contact with the mouth. The eggs make their way to the intestines and hatch into larvae that pass through the intestinal wall and into the bloodstream. From there they can travel to other body parts and can cause damage to whatever organ they have infected. The larvae don’t grow into adult worms in humans as they do in animals; however, the larvae can live for months to years in a human. 

Many people infected don’t have any symptoms, but symptoms can range from fever, coughing and wheezing to rashes, abdominal pain, swollen lymph nodes, vision problems and liver issues. Because symptoms aren’t always present, many cases go undiagnosed and the larvae may eventually die off with no issues. However, when symptoms do occur and diagnosis is confirmed, doctors may treat with steroids to help ease inflammation. 


Toxoplasmosis is most common in cats and is caused by a tiny parasite called Toxoplasma gondi. This one–celled parasite is most commonly found in cats but can also be found in other animals and can infect humans. It is believed that millions of people are infected with T. gondi but normal, healthy immune systems can usually keep the parasite from causing symptoms. However, people with immune issues can be more symptomatic, and pregnant women are at higher risk of passing the infection to their unborn babies and, in some cases, it can cause a miscarriage. For this reason, it is highly advised that pregnant women avoid contact with cat litter boxes and always wash their hands every time they come in contact with cats. 

In most cases, there are no symptoms, but when symptoms do occur they can present as a fever, swollen glands, muscle aches, headache and fatigue. 

Fungal Infections

Fungal infections are other commonly–seen infections passed from pets to humans, and the most common of the bunch are Tinea corporis and Tinea capitis, otherwise known as ringworm. Ringworm isn’t actually a worm but rather a fungus that can infect any area of the skin. When found in the groin area it’s called jock itch, on the feet it’s called athlete’s foot, and when found on the scalp or any other area of the body it’s called ringworm. 

Fungi are microscopic, plant–like organisms that can flourish in warm, moist environments. Ringworm appears as small, red, scaly patches usually round in shape, that tend to multiply and can cause an itching and burning sensation. Ringworm is extremely contagious and can be passed from animal to human, from human to human, and human to animal through contact. These fungi are treated with over–the–counter and prescription creams or sprays and can last anywhere from weeks to months in especially strong infections. 

Bartonella Henselae Bacterial Infections

Finally, while less commonly seen, Bartonella henselae bacterial infections, also known as cat scratch disease or cat scratch fever, can affect anyone who is in contact with cats. In the United States, most cases are seen in the fall and winter and most commonly affect children and those who work with cats due to the higher probability of being scratched or bitten. 

These bacteria live in the saliva of cats but don’t make the cats sick. Kittens can carry the bacteria for months, and it is spread from cat to cat through saliva contact as well as from infected fleas that move from cat to cat. The bacteria is also found on the feline nails from self–grooming, and when passed to humans, they cause a small bump or blister that develops within a few days of the bite or scratch. 

The infection causes swollen lymph nodes and sometimes a fever accompanied by fatigue, rash, sore throat and loss of appetite. Symptoms generally fade and lymph nodes return to normal in two to four months, but in rare cases, it can lead to other issues such as liver, spleen, lung and joint problems. This bacteria is not contagious from person to person and is only spread to humans through a scratch or bite by a cat, but most commonly from a kitten.

The long and short of it is that when working with animals, you need to exercise smart safety, sanitation and cleanliness protocols. Wash your hands after each pet, avoid touching your hands to your mouth before washing them, and always be aware of suspicious bumps, rashes or skin infections you see on the pets you handle. 

Cleanliness and sanitation will help to keep you and the pets you groom free from issues and infections for a happier groomer and a happier pet. ✂️

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