Zoonotic diseases are spread from animals to humans
Animals can carry germs that can spread diseases to humans, also known as zoonotic diseases, through direct or indirect contact. Here are 17 of the most common diseases humans can get from animals.
17 common diseases humans can get from animals
- Lyme disease: Lyme disease is the most common vector-borne disease in the United States, transmitted to humans when bitten by an infected tick. The causative bacterium is Borrelia burgdorferi and, rarely, Borrelia mayonii. Typical symptoms include fever, headache, fatigue, and a characteristic bullet-like skin rash called erythema migrans. If left untreated, the infection can spread to the joints, heart, and nervous system.
- Gastroenteritis: The most common gastric infection associated with E. coli is due to a strain that produces Shiga toxin. Gastroenteritis is often a foodborne illness that spreads from eating uncooked meat of infected cows, goats, sheep, or deer. Symptoms of infection include watery or bloody diarrhea, fever, abdominal cramps, nausea, and vomiting. The illness tends to be especially severe in young children, causing acute dehydration, kidney failure, and even death.
- Rabies: Rabies is an almost 100& fatal but preventable viral disease that can spread to humans when bitten or scratched by rabid animals (infected dogs, bats, raccoons, skunks, and foxes). The rabies virus infects the central nervous system, and the infection cannot be treated. Symptoms include inability to swallow, hydrophobia (fear of water), excruciating muscle spasms, and convulsions. The first dose of the rabies vaccine should be given within 24 hours of the exposure.
- Rat bite fever: Rat bite fever is caused by Streptobacillus moniliformis, and symptoms include fever, chills, body ache, rash, and enlarged lymph nodes. Untreated rat bite fever may be fatal in rare cases due to complications such as endocarditis, septic shock, or meningoencephalitis. Infection can occur through consumption of food or water contaminated with the urine and droppings of rodents carrying the bacteria.
- Rocky Mountain spotted fever (RMSF): RMSF is a bacterial disease that spreads through the bite of an infected tick. Most people who get sick with RMSF will have fever, headache, nausea, vomiting, and rash. RMSF can be deadly if not treated early with the right antibiotics.
- Cat scratch disease: This is a bacterial (Bartonella henselae) infection that is spread by cat scratches, cat bites, or even cat licks. Symptoms include fever, headache, poor appetite, lymph node enlargement, and exhaustion. Wounds may develop inflammation and pus formation.
- Psittacosis: Psittacosis is caused by Chlamydia psittaci and manifests as allergies, rash, or severe lung infection. It is spread from infected birds, particularly parrots.
- Brucellosis: Brucellosis is caused by a bacterium called Brucella and spread from infected farm animals (sheep, cattle, goats, and pigs) and pets (dogs). Typical symptoms include fever with chills, joint ache, headache, loss of appetite, and fatigue. Some individuals develop chronic diseases where the symptoms keep recurring. Complications include endocarditis (inflammation of the heart), epididymitis (testicular swelling), arthritis, or meningitis (infection of membranes over the brain). Pregnant women, children, and immunocompromised are at a higher risk of complications.
- Pseudomembranous colitis: Campylobacter jejuni causes an estimated 1.5 million illnesses each year in the United States, resulting in severe diarrhea and dehydration. Many get infected with C. jejuni by eating raw or undercooked poultry, seafood, and meat cooked in unhygienic surroundings, as well as by drinking untreated water. Most people recover with rest, hydration, and antibiotic therapy.
- Q fever: Q fever is caused by the bacterium Coxiella burnetii and is asymptomatic in goats, sheep, and cattle. C. burnetii bacteria are often found in the placenta, amniotic fluid, urine, feces, and milk of infected animals. People can get infected by breathing in dust contaminated by infected animal products. Symptoms include flu, fever, chills, fatigue, and muscle pain.
- Cysticercosis: Cysticercosis is a parasitic tissue infection caused by swallowing eggs found in the feces of a person who has an intestinal tapeworm. Eating undercooked pork can result in intestinal tapeworm if the pork contains larval cysts.
- Tularemia: Tularemia is a disease that can infect animals and cause endocarditis, arthritis, and fever with fatigue. Tick and deer fly bites, skin contact with infected animals (especially rabbits), drinking contaminated water, and laboratory exposure may cause the disease to spread to humans.
- Salmonellosis: Salmonellosis is caused by bacteria belonging to salmonella (Salmonella typhimurium, Salmonella enteritidis, and Salmonella newport). These bacteria can cause high fever, enteric symptoms (stomach cramps, vomiting, and diarrhea), jaundice, and gallbladder infection. It often spreads to humans from poultry (chicks, chickens, ducklings, ducks, geese, and turkeys).
- Toxoplasmosis: Toxoplasmosis is caused by a parasite called Toxoplasma gondii and is a leading cause of death attributed to foodborne illness in the United States. Although most people are symptomatic, women newly infected with T. gondii during or shortly before pregnancy and anyone with a compromised immune system (HIV) can experience complications. Intrauterine infection by T. gondii in an unborn child can cause severe brain developmental anomalies and even intrauterine growth retardation. In immunocompromised people, it can cause meningoencephalitis.
- Bubonic plague: About 7 cases of bubonic plague are reported in the United States every year. Fortunately, with the advent of antibiotics, the disease is completely curable. Symptoms include buboes (swollen lymph nodes) in the armpits and groins. High fever, loss of appetite, and episodes of profuse sweating have been noted as well.
- Influenza: Swine flu (H1N1) and bird flu (H5N1) are among the types of flu (influenza) humans can get from animals. Symptoms include high fever, cough, and respiratory distress. These flus are of viral origin.
- Leptospirosis: Leptospirosis is caused by Leptospira (spirochetes) and often accompanies floods and water logging. It spreads when humans come in direct contact with the urine of infected rats and other rodents. Symptoms include high fever, conjunctivitis, liver, and kidney failure. If diagnosed in time, it can be treated with antibiotics and supportive therapy.