Many diseases that spread between animals and people are uncommon and only occur in certain parts of the world or under specific conditions, whereas others are more common. It's important to be aware of the most common zoonotic diseases and those that can have the biggest impacts, including death.
Zoonotic Diseases of Concern in the United States
Disease (Cause) | Animals Involved | How It Is Spread | Symptoms in People | How to Prevent | Treatment |
|---|---|---|---|---|---|
Brucellosis (Brucella bacteria) | Cattle, sheep, goats, pigs, wild animals | Eating unpasteurized milk or cheese | Stomach pain, fever, chills, cough, joint pain | Vaccinate pets in geographical areas where brucellosis is present Avoid eating unpasteurized dairy products | Antibiotics |
COVID-19, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) (coronaviruses) | Probably infected bats | Breathing contaminated air from an infected person Direct contact with an infected person or contaminated objects | Fever, sore throat, loss of smell, difficulty breathing | Get vaccinated as medically appropriate Wash hands frequently Wear protective masks | Antivirals Monoclonal antibodies |
Influenza, zoonotic (avian influenza viruses H5N1 and H7N9; swine influenza virus) | Poultry, pigs, wild birds | Direct contact with infected animals Indirect contact with contaminated areas | Typical flu symptoms (fever, cough, sore throat, aches) May be mild or very severe | Get vaccinated as medically appropriate Wash hands frequently | No specific treatment Rest, fluids |
Lyme disease (Borrelia burgdorferi bacteria) | Ticks, which get the disease from infected deer and mice | Tick bite | Bull's-eye rash, headache, fever, joint swelling | Wear insect repellent Wear protective clothing Check body for ticks after being in wooded areas | Antibiotics |
Plague (Yersinia pestis bacteria) | Fleas, often from prairie dogs or squirrels | Contact with infected animals or their bodily tissues, urine, blood, or saliva Flea bite | Swollen lymph nodes, vomiting, diarrhea, fatigue, aches | Apply flea control to pets Avoid wildlife Seal or otherwise protect your home from infestation by wild rodents | Antibiotics, usually in a hospital |
Rabies (rabies virus) | Contact with saliva from infected animals via bites Scratches from infected animals | Fever, aggression, irritability, fear or avoidance of water, death | Vaccinate pets Avoid contact with wildlife and unfamiliar animals | Vaccination immediately after exposure | |
Ringworm (various fungi) | Any animals, especially young animals or those with weakened immune systems | Direct contact with infected animals or surfaces they contacted | Round, red, often itchy skin patch with a crust or ring around it | Avoid contact with animals that have cuts or sores and their bedding | Antifungals |
Salmonellosis (Salmonella bacteria) | Reptiles, chickens | Direct contact with infected animals or their droppings Eating undercooked meat or eggs, unpasteurized milk or cheese, or contaminated food or water | Diarrhea, blood in stool, vomiting, fever | Wash hands after touching animals or raw food Cook poultry and eggs thoroughly Disinfect countertops and cooking surfaces | Antibiotics |
Toxoplasmosis (Toxoplasma gondii parasite) | Cats | Contact with cat feces (poop) Eating contaminated produce Eating undercooked meat or shellfish | Pregnant women and people with poor immune systems: flu-like symptoms, swollen lymph nodes, possible brain or eye damage Can be passed to unborn fetuses | Avoid scooping cat litter if pregnant or if immune system is weakened Wash all produce Cook food thoroughly | Antiparasitics, with or without antibiotics |
West Nile fever (West Nile virus) | Mosquitoes | Mosquito bite | Mild: fever, headache, rash, red or itchy eyes Severe: high fever, tremors, seizures, coma | Wear insect repellent Wear protective clothing Avoid areas of standing water | No specific treatment Rest, fluids |
Most zoonotic infections come from wild animals or insects, not from pets. The accompanying table lists the main zoonotic diseases of concern in the United States, their symptoms in people, the ways they spread, how to avoid them, and treatment information. For more comprehensive lists of zoonoses, see the detailed tables in the topic Zoonotic Diseases in the professional version of the Manual.
