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Between 2012 and 2014, 160 people became infected by Salmonella Cotham, a rare strain of bacteria that causes vomiting, diarrhea, and fever. Sixty-one people were hospitalized. The culprit? Bearded dragon lizards bought from pet stores across 36 states. Salmonella is relatively common on reptile skin, and it’s likely this rare strain accidentally spread from lizard to lizard by the breeders who supplied the animals to the pet stores.

But according to a review in the Canadian Medical Association Journal, it’s not just exotic pets that can make people sick.

“Every pet is carrying something that can be transmitted to people, and every person is at risk of infection,” Jason Stull, a veterinarian and co-author on the study, tells Popular Science. Although pathogens from pets have been known to infect perfectly healthy people, these infections are more common and more severe in people with weakened immune systems, such as children, cancer patients, pregnant women, and elderly folks.

Unfortunately, doctors and patients are largely unaware of the risks that pets can present. “Physicians do not regularly ask about pet contact, nor do they discuss the risks of zoonotic diseases with patients, regardless of the patient’s immune status,” write the authors of the CMAJ study.

The Centers for Disease Control and Prevention keeps a running list of outbreaks caused by pets and pet products, but most cases of pet-associated infections likely go unreported, the authors note. They suggest that working more closely with veterinarians could help doctors recognize when a pet is causing a patient’s health problems, and pinpoint how to prevent infection.

Some species have higher risks than others, says Stull, including baby chicks, hedgehogs, reptiles, and rodents. People whose immune systems are compromised–for example, due to chemotherapy, HIV, or immunosuppressants–should talk to their doctor before getting one of these pets.

If you already own a pet, there are lots of things you can do to reduce your risk of getting a nasty bug from Fluffy or Mr. Whiskers:

  • Wash your hands after touching your pet.
  • Wear gloves when you’re cleaning up after it.
  • Wash bites and scratches immediately.
  • Keep your cats indoors, and don’t let your dog eat garbage or drink from the toilet.
  • Keeping your pet healthy will help keep you safe, too.

Check out the gallery below to read about gross pet-borne infections, which can range in severity from mild to (in very rare cases) deadly.

Capnocytophaga canimorsus (Not Shown)

C. canimorsus lives in the saliva of cats and dogs. In one study, the bacterium was detected in 74 percent of dogs and 57 percent of cats. Although human infections are extremely rare, when C. canimorsus does infect humans, it can be life-threatening. It’s spread through bites and scratches, but some people have contracted it from just being around pets. Symptoms can include blood poisoning, shock, respiratory distress, and meningitis. Prevention: Wash bites and scratches immediately with antiseptics and antibiotics.

Bartonella henselae (Cat Scratch Disease)

A bite or scratch from a cat could help this bacteria get under your skin. Cat scratch disease, or Bartonellosis, is typically characterized by lymph node swelling, fatigue, and (just like the Ted Nugent song) fever. The disease can be treated with antibiotics, but serious complications can occur in people with weakened immune systems. Prevention: Wash bites and scratches immediately with antiseptics and antibiotics.

Campylobacter jejuni

It may look like spiral-shaped macaroni, but you do not want to eat this microbe. Campylobacter jejuni is one of the most common causes of food poisoning. (You know the symptoms.) Though it’s commonly spread through improperly cooked meats, C. jejuni is also present in the feces of cats and dogs, where it can spread to humans. Prevention: Wash your hands before eating.

Brucella canis

This bacteria, which causes miscarriages and stillbirths in dogs, is spread through vaginal secretions, urine, and potentially saliva. In humans, B. canis can cause fever, fatigue, and weight loss, as well as swelling of the liver, spleen, and lymph nodes. The disease is rare in humans, but probably underdiagnosed. Prevention: Wash your hands after touching your pet.

Chlamydophila psittaci

C. psittaci lives in the snot and feces of pet birds. When inhaled by humans, symptoms can include fever, headache, chills, and pneumonia. In rare cases it can also lead to hepatitis, arthritis, and respiratory failure. Prevention: Wear a mask and glove while cleaning bird cages; clean cages daily.

Leptospira interrogans

This spiral-shaped bacteria, which resides in the urine of various pets, can corkscrew its way through your skin and into the bloodstream. From there, L. interrogans causes fever, vomiting, and diarrhea. If left untreated, the infection can lead to kidney damage, meningitis, liver failure, and even death. Prevention: Avoid the urine of cats, dogs, and rodents. Do not swim in water that may have been peed in by these animals.

Toxoplasma gondii

According to the CDC, more than 60 million people in the United States may be infected with the Toxoplasma parasite, which is spread through cat feces (as well as soil and uncooked meat). Most peoples’ immune systems are able to fend off illness. But in people with compromised immune systems, such as pregnant women, toxoplasmosis can damage the brain, eyes, and other organs. Symptoms include blurred vision, muscle aches, and flu-like symptoms. Prevention: Change your cat’s litter box daily. Use gloves, and wash your hands afterwards. Keep your cat indoors, and don’t touch stray cats.

Lymphocytic choriomeningitis

Hamsters, mice, and other rodents can carry this virus. It spreads to humans when urine, droppings, or saliva come into contact with the eyes, nose, mouth, or broken skin. An infection starts with mild symptoms such as fever, vomiting, and diarrhea. Then it escalates to inflammation of the heart and brain, resulting in temporary or permanent neurological damage. The disease is particularly dangerous in pregnant women and immunocompromised people, but usually is not fatal. Prevention: Wash your hands after handling rodent cages and bedding.