What you need to know:

More than 85 Ocean County New Jersey residents were reportedly exposed to measles (rubeola) while attending a party in New York during the second week of December. Eighteen cases of measles were confirmed in Ocean County last week, with six additional suspected cases being investigated.

In 2000, measles was declared eradicated from the U.S.; however, over the last 18 years cases have begun to increase. Measles is thought to be on the rise because of the growth in the number of unvaccinated Americans. The spread of measles is more common in areas where groups of individuals remain unvaccinated.

Measles is a viral respiratory illness with a clinical presentation that includes the three Cs: coryza, cough, and conjunctivitis. Patients often have a high fever, up to 105 degrees F, malaise, Koplik spots, and the hallmark maculopapular rash which appears approximately two weeks following exposure. Persons infected are contagious for a little more than a week, beginning four days before the rash appears until four days after the rash appears. Immunocompromised patients may not develop a rash, so measles should be on the list of differential diagnoses if other associated symptoms are present.

Measles is highly contagious, infecting nine out of ten persons at risk who encounter the virus. It is spread through direct droplet contact or through the air after an infected patient sneezes, coughs, or breaths. The virus may remain in the air for up to two hours, exposing people who were not in direct contact with the infected person.

Persons at highest risk for serious illness and complications from measles include children under age 5, adults over age 20, pregnant women, and those who are immunocompromised. The greatest defense against measles is the vaccine, administered in combination as the measles-mumps-rubella (MMR) vaccine to children between 12 months and 12 years of age. One dose is 93% effective and two doses are 97% effective against measles.

Read more about measles:

Harrison’s Principles of Internal Medicine, 20e: Chapter 200. Measles (Rubeola)

Current Diagnosis and Treatment: Pediatrics: Chapter 40. Infections: Viral and Rickettsial

The Color Atlas of Family Medicine: Chapter 126. Measles