Is It Contagious? What Diseases Are Contagious?

Viral and bacterial pink eye infections are contagious and spread very easily. Since most pink eye is caused by viruses for which there is usually no medical treatment, preventing its spread is important. Poor hand-washing is the main cause of the spread of pink eye.

Psoriasis is a common skin disorder that produces thick red plaques covered with silvery scales. Psoriasis is not contagious and cannot be passed from person to person, but it can occur in members of the same family.

Influenza, commonly shortened to "flu," is an extremely contagious respiratory illness caused by influenza A or B viruses.

Canker sores are not thought to be contagious. They don't pose any health risk other than the discomfort that comes along with them.

Cold sores, also commonly called fever blisters, are caused by herpes simplex virus type 1. The virus is highly contagious. Cold sores usually appear on the lips, chin, cheeks and in the nostrils.

Scabies is a contagious skin disease caused by the mite Sarcoptes scabiei var. hominis. The primary symptom (and incredibly itchy, pimply rash) results when the female mite burrows into the skin and deposits eggs.

Note: The term "scabies" refers to both the condition and the mite which causes it.

Infectious mononucleosis (commonly known as "mono") is contagious and spread by person-to-person contact, mainly through saliva. Infectious mononucleosis is also known as the "kissing disease." Malaria, a very dangerous disease, is not contagious. Malaria is transmitted by Anaopheles mosquitoes that carry the malaria parasite.

When you have a cold, you are most contagious during the first 24 hours through the first few days of catching a cold virus.

Yes, warts are contagious. You can get warts from touching a wart on someone else's body or by coming in contact with surfaces that touched someone's warts, such as towels or bathmats.

Eczema is a general term for many types of skin inflammation, also known as dermatitis. Eczema is not contagious, but since it is believed to be at least partially inherited, it is not uncommon to find members of the same family affected.

The rash, blisters, and infamous itch associated with poison ivy, oak, and sumac come from urushiol (pronounced oo-roo-shee-ohl) found in the sap of these plants. Neither the oozing blisters nor the fluid cause further spread on the affected person's body, and the rash can not spread to another person.

Until it drains and heals, an active skin boil is contagious. The infection can spread to other parts of the person's body or to other people through skin-to-skin contact or the sharing of personal items.

Active TB is very contagious. This infection is caused by bacteria. The infection usually stays in the lungs, but the bacteria can travel through the bloodstream to other parts of the body.

Group A Streptococcus bacteria are responsible for a variety of health problems including strep throat, impetigo, cellulitis, scarlet fever and necrotizing fasciitis (flesh-eating disease).

Hives are not contagious. Hives are produced by histamine, which is made by the body. Histamine causes fluid to leak from local blood vessels, leading to swelling in the skin.

Shingles is indeed contagious. The virus that causes shingles is the same virus that causes chicken pox.

Athlete's foot, or tinea pedis, is spread through contact with infected skin scales or contact with fungi in damp areas (showers, locker rooms, swimming pools). Treatment may include topical creams (applied to the surface of the skin) or oral medications. To prevent athlete's foot, avoid wearing other people's shoes or slippers.