What is Measles (Rubeola)?
Rubeola, or “red” measles, is a respiratory disease caused by a paramyxovirus, genus Morbillivirus with a core of single-stranded RNA. Measles is highly contagious and causes a systemic infection that begins in the nasopharynx. The virus is shed through respiratory secretions (nasal discharge, coughing sneezing) for four days before symptoms appear until three to four days after rash onset, when it is most easily transmitted.
Before the first measles vaccine was licensed in the U.S. in 1963, measles increases were seen generally in winter and spring with cyclical increases in reports of measles cases every two to three years.
Rubeola (not to be confused with rubella, a less serious infection commonly known as “German measles”) symptoms begin 10-12 days after close contact with someone infected with measles. Symptoms and start with a fever, cough, runny nose, conjunctivitis, white spots in the mouth and progresses to a rash that starts on the face and spreads to the rest of the body and lasts for about a week. Complications include very high fever, diarrhea, otitis media, seizures, pneumonia, encephalitis (0.1% reported) and very rarely subacute sclerosing panencephalitis (SSPE - a progressive, debilitating and deadly brain disorder) and death.1,2,3
Measles can also be mistaken for influenza before the signature measles rash appears around the fourth or fifth day after the fever begins.4,5
Although the measles virus is closely related to certain animal diseases such as canine (dog) and porcine (pig) distemper, it is a disease unique to humans, and is not found in animals. Measles is highly contagious and is seasonal, occurring in cyclical “waves” around the world.
Doctors diagnose measles by looking for the presence of tiny white specks surrounded by a red halo inside the cheeks of an infected person’s mouth.6 As the fever progresses, cold symptoms develop, such as cough, runny eyes and nose. Conjunctivitis (inflammation or infection of the membranes of the eyes) can be a complication.
Sometimes persons with measles will not be able to tolerate bright lights. They also may have a sore, red mouth. While rubella and scarlet fever can also have a measles-like rash, usually there is no cough, runny nose and cold symptoms (coryza) or conjunctivitis.
Other occasional illnesses that may develop along with measles are croup, bronchiolitis and pneumonia. Persons who have had measles infection usually will acquire long-lasting immunity.7
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1 Kasper D, Fauci A, Longo D, et al. Measles. Harrison’s Principles of Internal Medicine 16th Edition. 2005.
2 Grabenstein JD. ImmunoFacts: Vaccines and Immunologic Drugs 2011. Wolters & Kluwer. p 293.
3 Kasper D, Fauci A, Longo D, et al. Measles. Harrison’s Principles of Internal Medicine 16th Edition. 2005.
4 Perry RT, Halsey NA. The Clinical Significance of Measles: A Review. J Infect Dis. 2004. 189 (Supplement 1): 54-516. Online. (Accessed March 2012)
5 National Institutes of Health. Emerging & Re-emerging Infectious Disease—Student Activities 5—Making Hard Decisions Measles. No date. Online. (Accessed March 2012)
6 National Institutes of Health. Emerging & Re-emerging Infectious Disease—Student Activities 5—Making Hard Decisions Measles.
7 Kasper D, Fauci A, Longo D, et al. Measles. Harrison’s Principles of Internal Medicine. 2005 16th Edition.