In-depth

Adult Still's disease

Daily fevers, achy joints and an intermittent, salmon-pink rash may be an indication that you have a rare inflammatory disorder called adult Still's disease.

Cold sore

Cold sores are common and annoying. You can't cure or prevent them, but you can take steps to lessen their frequency and duration.

Complete blood count

A complete blood count can be used to evaluate your overall health, detect a wide range of disorders, or monitor a medical condition or treatment.

CT scan

A CT scan is an imaging test that uses X-rays to produce detailed images of the inside of your body.

Diphtheria

Diphtheria — Comprehensive overview covers symptoms of this infection that's preventable with a vaccine.

Gonorrhea

Gonorrhea is a highly contagious sexually transmitted infection. Without treatment, serious complications can occur.

HIV/AIDS

More than 39 million people are living with HIV — the virus that causes AIDS. Millions more are likely to become infected in the next decade.

Hodgkin's lymphoma

Inflammatory breast cancer

Inflammatory breast cancer occurs when cancer cells clog lymphatic vessels in the skin of the breast. It's a rare but deadly form of cancer.

Kawasaki disease

Kawasaki disease — the leading cause of acquired coronary disease in children — causes artery wall inflammation throughout the body. It affects children younger than age 5.

Leukemia

Leukemia is a cancer in which abnormal white blood cells proliferate. Although it's often perceived as a children's disease, leukemia also occurs in adults.

Mononucleosis

Mononucleosis — also called kissing disease because it can be spread by kissing — causes fatigue, fever and swollen lymph glands.

Mosquito bites

Mosquito bites are usually just annoying, but can sometimes cause disease. Take steps to protect yourself and learn how to relieve itching if you've been bitten.

Needle biopsy

Find out what to expect during a needle biopsy.

Non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma is cancer originating in the lymphatic system. It's caused by abnormal white blood cells, and often the only sign is swollen lymph nodes.

Noonan syndrome

Noonan syndrome is caused by a mutation in one of the genes responsible for normal development in many parts of the body, including the heart.

Plague

Plague is a disease carried by rats and other rodents. The risk of developing plague is low, and most cases occur in Africa.

Roseola

Roseola is a common infection of childhood. The condition causes a fever that lasts several days, followed by a rash on the trunk and neck.

Rubella

Rubella, a contagious viral infection, is most dangerous to pregnant women. Rubella can be prevented with the combined measles-mumps-rubella vaccine.

Runny nose

Runny nose: What's causing your sniffles?

Scarlet fever

Scarlet fever is a bacterial infection that causes a rash, fever and sore throat and usually affects children and adolescents.

Sexually transmitted diseases

Strep throat

Strep throat is a bacterial throat infection. It typically causes a very sore throat and is treated with antibiotics.

Swimmer's ear

Swimmer's ear, an infection in the outer ear, is usually caused by bacteria and is more common in ears exposed to water for long periods.

Syphilis

Syphilis, a sexually transmitted infection, first appears as painless sores on your genitals, rectum or mouth. Early diagnosis is important.

Tonsillitis

Tonsillitis — a common cause of sore throat in children — is usually treated with self-care and, in some cases, antibiotics.

Tooth abscess

Tooth abscess — Comprehensive overview covers symptoms, causes, treatment of this painful tooth condition.

Toxoplasmosis

Toxoplasmosis is an infection caused by a parasite. It doesn't make most people ill, but infants and people with HIV/AIDS are at risk of complications.

Trench mouth

Although trench mouth is much less common than in years past, some people still get this painful gum infection. Brushing and flossing are keys to prevention.

Tularemia

Tularemia is a rare, highly infectious disease spread by insects and wild animals. Landscapers, hunters and laboratory workers are especially at risk.

West Nile virus

West Nile virus infection usually resolves on its own, but occasionally it can be serious.

Whipple's disease

Whipple's disease is a rare bacterial infection that affects primarily the gastrointestinal system, and can be treated successfully with antibiotics.

Jan. 02, 2014

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