RELATED: The Worst Thing You’re Touching at Walmart, Infectious Disease Doc Warns. Cats can become infected with cat scratch disease through exposure to fleas and ticks, and can pass it on by biting, scratching, or licking you. The CDC estimates that up to half of all cats are exposed to cat scratch disease during their lifetime, but only a small minority of infected cats will display symptoms. These may include vomiting, swollen lymph nodes, fatigue, or loss of appetite. Humans who contract cat scratch fever from their pets may notice blisters or bumps at the site of their scratch or bite. Other symptoms can include swollen lymph nodes, fever, eye infection, muscle pain, and more, the CDC says. RELATED: If You Notice This on Your Skin, Get Your Blood Checked, Experts Say. Many cats carry parasites such as hookworm, ringworm, tapeworm, and roundworm, and can easily pass these on to their caretakers through direct contact, or through contact with their feces during litter box changes. While symptoms vary in humans depending on the type of parasite, possible symptoms include a red, squiggly line under the skin (hookworm), an itchy, ring-shaped rash (ringworm), seeing segments of the parasite in your feces (tapeworm), or symptoms that affect the eyes and organs (roundworm). The best way to protect yourself from parasites is to regularly bring your cat to the vet for screenings, wash your hands after petting or playing with your cat, and limit exposure to your cat’s litter box. The CDC also recommends disinfecting your floors regularly and not walking barefoot in your home. MRSA is short for methicillin-resistant Staphylococcus aureus, a form of antibiotic-resistant bacteria that is found on the skin and in the noses of infected animals and humans. You can contract MRSA from your cat while petting them, even if your cat does not appear to be sick. Similarly, many people who have MRSA do not show symptoms. However, some people with MRSA may develop a serious dermatological infection that can appear as a red, swollen, pus-filled bump on the skin. A small portion of MRSA patients experience life-threatening complications when the bacteria spreads to their lungs or bloodstream. For more health news sent directly to your inbox, sign up for our daily newsletter. Salmonella infections are most often spread through contaminated food, but can also be passed from animals to humans, and from person to person. Your cat may become infected if they eat raw cat food, contaminated cat food, or if they eat an infected bird, rodent, or other animal.ae0fcc31ae342fd3a1346ebb1f342fcb While cats do not typically show symptoms of Salmonella poisoning, you may notice unpleasant gastrointestinal symptoms if you become infected. According to the CDC, symptoms may include diarrhea, fever, and abdominal cramps, which most often develop between six hours and four days after infection and persist for up to a week. While you may recover without treatment, many doctors recommend treating a case of Salmonella infection with antibiotics. Toxoplasmosis is another good reason to practice caution when it comes to your cat’s litter box. “Cats become infected by eating infected rodents, birds, or other small animals,” explains the CDC. “The parasite then sheds in the cat’s feces, contaminating the environment or the cat’s litter box.” Pregnant women and people with autoimmune disease are at highest risk of developing serious complications from toxoplasmosis. In severe cases, it can cause brain disease or birth defects, though most people with toxoplasmosis will experience mild, flu-like symptoms. Speak with your doctor if you have a cat at home and believe you may be showing signs of pet-related illness. RELATED: Storing This in Your Pantry Is Attracting Mice to Your Home, Experts Warn.