Measles (Rubeola)

What Is It?

Measles, also known as rubeola, is a very contagious respiratory infection that causes cold symptoms, fever and a characteristic rash. It is caused by the measles virus, which usually spreads from person to person through coughs and sneezes, and through contact with used tissues, shared drinking glasses, dirty hands that touched a runny nose, or other contaminated surfaces. Once the virus enters the body, the infection spreads throughout the respiratory tract to the skin and to other body organs.

In the respiratory tract, the measles virus damages the lining of the breathing passages, causing a runny nose, nasal congestion and cough. In the skin, the virus triggers the typical measles rash. A person with measles is contagious (can infect others) from one to two days before any symptoms begin (or three to five days before the rash) to four days after the rash appears.

Measles typically causes moderate illness. In younger children, fairly common complications include middle-ear infection (otitis media), pneumonia, croup and diarrhea. In adults, the illness tends to be even more severe. It is not unusual for older patients to require hospital treatment for measles-related pneumonia. In one of every 1,000 cases, measles produces encephalitis (brain infection), with an immediate risk of seizures, coma and death, and a long-term risk of mental retardation, epilepsy or subacute sclerosing panencephalitis, an extraordinarily rare chronic form of measles encephalitis that causes brain damage. In unusual cases, measles also can directly attack the digestive organs (including the liver), the heart muscle or the kidneys. A pregnant woman who is infected with measles has an increased risk of premature labor, miscarriage or delivery of a low-birth-weight infant.

Before an effective vaccine was available, there were at least 400,000 cases of measles reported each year in the United States, with probably more than 3 million unreported cases. Now, the number of cases has decreased by more than 99 percent. Only 116 cases were reported in the United States in 2001, with most involving people who came to the United States from other countries.

Symptoms

Measles symptoms begin about eight to 12 days after exposure to a contagious person. The first symptoms include cough, runny and stuffy nose, a general, sick feeling (malaise), red eyes with tearing (conjunctivitis), and a fever up to 105 degrees Fahrenheit. Within two to four days, these symptoms can be followed by the appearance of Koplik's spots in the mouth. These are blue-white or gray spots with a red background, located inside the cheeks near the back molars. They develop at about the same time or just before the measles rash.

The measles rash usually is characterized by pink or bright red spots that are not itchy. It typically begins at the hairline and behind the ears, then spreads downward to the neck, trunk, arms and legs, palms and soles. The rash begins to fade about four days later in the same order that it appeared, first from the head and neck, then the trunk and arms and legs. The fading rash may leave behind a temporary brownish discoloration or flakiness that clears two to three days later. Some patients also have enlarged lymph nodes (swollen glands), diarrhea and vomiting.