Measles Outbreaks Worry CDC
Surge in Measles Cases Blamed on Parents Who Won't Vaccinate Kids
2 Outbreaks, 2 Pockets of Unvaccinated Kids continued...
That would be worrisome, because it will take 95% vaccine coverage to keep measles from re-establishing itself in the U.S. In the U.K.. fears that the measles vaccine might be linked to autism dropped vaccination coverage there to 80% to 85% of the population.
Very high coverage rates are necessary because measles is one of the most contagious diseases known to man. If a person with measles coughs in a room of 100 unvaccinated people, Seward says, 90 to 95 of those people will get the measles.
And many of these people would get very ill. Uncomplicated measles is a serious illness, but some kids who get the illness come down with life-threatening encephalitis or pneumonia. In the years before vaccination became common, a few children each year developed a very rare measles complication called subacute sclerotic panencephalitis -- a degenerative brain disease that is almost always fatal but which can take up to 10 years to kill.
"Encephalitis complicates one to three in every 1,000 measles cases, and you can never tell which child will be the unlucky one that has a severe complication," Seward says. "We have not seen measles encephalitis yet this year, but we could. And we have seen cases of pneumonia, which is another serious complication."
Most at risk are people who can't take the measles vaccine -- very young children and people suffering cancer or immune disorders.
Fortunately, none of the U.S. measles cases this year has been fatal, although 15 people were hospitalized -- including four babies under 15 months of age. But there were two deaths in Europe this year, one in Italy and one in the U.K.
"Both of these children were immuno-compromised and could not take the vaccine, but they would have been protected if there were higher immunity in their community due to better vaccine coverage," Seward said.
States With Measles Outbreaks
The last time the U.S. had as many measles cases at this time of year was 1996.
Fifteen states have seen measles this year:
- Illinois (32 cases)
- New York (27 cases)
- Washington State (19 cases)
- Arizona (14 cases)
- California (14 cases)
- Wisconsin (7 cases)
- Hawaii (5 cases)
- Michigan (4 cases)
- Arkansas (2 cases)
- District of Columbia (1 case)
- Georgia (1 case)
- Louisiana (1 case)
- Missouri (1 case)
- New Mexico (1 case)
- Pennsylvania (1 case)
- Virginia (1 case)
Measles vaccination is recommended for all healthy children, with one dose at age 12 to 15 months and a second dose at the time of school entry. However, vaccination as early as age 6 months is advised for U.S. children traveling abroad or during community outbreaks.
The CDC's updated measles report appears in the Aug. 22 issue of Morbidity and Mortality Weekly Report.