Chicago-Area Measles Outbreak Focuses Attention on Preschoolers' Vulnerability
Five children under the age of 1 who attended a KinderCare facility in Palatine, Ill., have been diagnosed with measles, Illinois and Cook County health officials said Wednesday
It is unclear whether these measles cases are related either to the multistate outbreak that originated in California, or to a single adult case in Cook County, Ill., that was diagnosed in mid-January, health officials said. But the cases put a new spotlight on the highly contagious disease—the virus lives in the air and on surfaces for up to two hours—and the susceptibility of young children. Dr. Terry Mason, the chief operating officer of the Cook County Department of Public Health, told the Chicago Sun-Times that residents should expect more cases. "The cat is out of the bag," he told the newspaper.
Two of the infants in Illinois have been diagnosed through tests, and the remaining three have been diagnosed based on clinical criteria. All of the other children and staff at the facility have been asked to stay away for 21 days if they have not received a vaccination for measles. The Centers for Disease Control and Prevention recommends that most children receive their first dose of measles vaccine at 12 months, and a second dose between ages 4 and 6.
The Los Angeles Times ran an investigative report Tuesday that found the measles vaccination rate at 1,500 day-care centers in California was below 92 percent, which is the threshold epidemiologists believe is necessary to prevent rapid spread of the disease. California has been the epicenter of an outbreak that started at Disneyland in Anaheim and has since spread to eight states and Mexico. The data gathered by the newspaper showed that preschools tended to have higher vaccination rates than day-care centers, with some approaching 100 percent.
The day before news of the Chicago-area outbreak became public, the advocacy organization Trust for America's Health released a report saying that 17 states have measles vaccination rates below 90 percent for 19- to 35-month-olds. The organization, which gathered its information from a 2013 CDC survey of states, used the 90 percent threshold to correspond to a goal in its Healthy People 2020 initiative. (Illinois' vaccination rate for that year was 91.4 percent, but as noted, the children in the most recent outbreak were younger than the recommended vaccination age.)
Nationally, 91.1 percent of preschoolers have been vaccinated against measles, but those outlier states are a concern, the organization said. "Sadly, there is a persistent preschooler vaccination gap in the United States," said Jeffrey Levi, the executive director of the organization, in a press release Tuesday. "We're seeing now how leaving children unnecessarily vulnerable to threats like the measles can have a tragic result."
In May, months before the recent spate of cases, Education Week reported that states are tightening their school vaccine laws. California, for example, allows a personal exemption from vaccination, but in 2012 required that parents also submit a signature from a health-care practitioner to get that exemption. Some state lawmakers are introducing legislation to do away with the personal belief exemption altogether.