How is disease caused

Some infections spread to people from an animal or insect, but are not contagious from another human. Lyme disease is an example: You can't catch it from someone you're hanging out with or pass in the street. It comes from the bite of an infected tick. Contagious diseases such as the flu, colds, or strep throat spread from person to person in several ways. Related Content:. What are Staphylococcal infections? What are Streptococcal infections? What is Salmonella? What is tuberculosis?

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Most infectious diseases have only minor complications. But some infections — such as pneumonia, AIDS and meningitis — can become life-threatening. A few types of infections have been linked to a long-term increased risk of cancer:. In addition, some infectious diseases may become silent, only to appear again in the future — sometimes even decades later. For example, someone who's had chickenpox may develop shingles much later in life.

Prepare food safely. Keep counters and other kitchen surfaces clean when preparing meals. Cook foods to the proper temperature, using a food thermometer to check for doneness. For ground meats, that means at least F 71 C ; for poultry, F 74 C ; and for most other meats, at least F 63 C. Also promptly refrigerate leftovers — don't let cooked foods remain at room temperature for long periods of time.

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Overview Infectious diseases are disorders caused by organisms — such as bacteria, viruses, fungi or parasites. Request an Appointment at Mayo Clinic. What are superbugs and how can I protect myself from infection? Share on: Facebook Twitter. Show references Facts about infectious disease. Infectious Disease Society of America. Accessed May 29, Jameson JL, et al. Approach to the patient with an infectious disease. In: Harrison's Principles of Internal Medicine.

New York, N. Clean hands count for safe health care. Centers for Disease Control and Prevention. Kumar P, et al.