Measles, also called rubeola, is a highly contagious viral infection that can be found around the world. Fortunately, since a vaccine was developed in 1963, fatal measles infections have been reduced by 85%. Even though an effective vaccine is available and widely used, measles continues to occur even in developed countries.
Measles TransmissionMeasles is caused by a virus from the Paramyxoviridae family, and it's transmitted in respiratory droplets. It only takes a small amount of respiratory droplets to cause an infection. You can come in contact with respiratory droplets if:
- You come in direct contact with saliva or mucus from an infected person, like when you kiss someone who's infected.
- Someone near you sneezes or coughs into the air and you breath in some of the droplets.
- Someone coughs or sneezes into his hand and then touches something without sanitizing his hands, and then you touch it soon after and then wipe your nose or your mouth.
Measles InfectionAfter someone who hasn't been immunized against measles comes in contact with the virus, the following chain of events occurs:
- The virus invades the mucus membranes of the nose and respiratory tract and spreads to the lymph nodes.
- The virus enters the bloodstream and infects other organs like the skin, kidneys and liver.
- Your immune system starts making antibodies to fight off the infection.
- Because your immune system is busy fighting off the measles virus, it's less effective at fighting off other viruses or bacteria.
- Finally, in most cases, your immune system is able to kill off the remaining virus and you recover from the infection.
Measles SymptomsIn uncomplicated measles infections, the first symptoms start about 10 to 12 days after the virus invaded the body. The first symptoms include cough, runny nose, red eyes, fatigue and a fever that can get as high as 104-105°F. These symptoms are the same as the early symptoms of influenza. This is when the infected person is the most contagious.
Next, the person develops a typical rash on the inside of the mouth called Koplik spots. These are 1-2mm blue-white spots on the inside of the cheeks close to the molars. Two days later the typical measles rash starts. The Koplik spots are usually gone 2 days after the rash appears.
The typical measles rash starts out with red spots and bumps on the forehead and hairline. The rash moves down the body and the spots start to merge together especially on the face. After about 4 days the rash starts to fade in the same pattern as it started. The whole illness can last up to 10 days.
Atypical MeaslesAtypical measles can occur in people who were immunized with a killed virus vaccine that was used from 1963-1967 and then exposed to the original virus. It can also occur in people who were immunized with the current vaccine but, for some reason, failed to develop immunity, and in people who are immunosuppressed.
The symptoms of atypical measles are different and more severe than the symptoms of typical measles. The rash starts on the extremities and moves in to the trunk and can have blisters, bruises, or look like hives. In addition, the person with atypical measles doesn't usually have the Koplik spots, runny nose, or red eyes. They do get pneumonia with swelling in the lungs and in the ankles. The infection usually goes away on its own without any complications.
Measles ComplicationsThe most commonly reported complications of measles are pneumonia, diarrhea, and middle ear infections. Other less common complications include hepatitis, low blood platelet count, and several different brain infections. The people who are more likely to get measles complications are children under 5 years old and adults over 20 years old.
Measles DiagnosisMeasles is usually diagnosed when the rash appears, since prior to the rash the symptoms are almost the same as the more common infection, influenza. Blood tests may be done looking for the number of antibodies to the measles virus at the time of diagnosis, compared to the number of antibodies once the illness is over. Of course, the infection often is over by the time the series of tests have been performed.
Measles TreatmentThe treatment of typical measles is mainly supportive, treating the symptoms that are bothering the infected person the most. If the person has a complication like pneumonia or a middle ear infection, they are treated with antibiotics.
Measles PreventionMeasles is best prevented with vaccination. The vaccine contains live attenuated virus which means the virus has been altered so it can't cause the disease. In 1971, the measles vaccine was combined with vaccines against rubella and mumps to give us the current MMR vaccine. MMR is given between 12 to 15 months of age and again between 4 to 6 years of age.
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