Is your staff immune to measles?
Some 9 million U.S. youth now unvaccinated
Employee health professionals should ensure the all staff have immunity to measles, as some 9 million U.S. children — 1 in 8 of those age 17 and younger — are susceptible to a virus that can cause chaotic outbreaks in healthcare facilities, researchers recently reported in San Diego at IDWeek 2015.
If the trend continues to increase, millions of susceptible youth — and eventually young adults — could reach a tipping point in population herd immunity, meaning more frequent and sustained measles outbreaks could occur.
“We can’t be complacent — we don’t have a very wide buffer before these population-level immunity estimates start dipping below critical levels,” said lead researcher Robert Bednarczyk, PhD, a professor in the Rollins School of Public Health at Emory University in Atlanta. “If our measles immunization starts to falter we could see immunity below what we need to [prevent] transmission. We could start seeing larger outbreaks or outbreaks that sustain over longer periods of time.”
An undiagnosed case of measles in a hospital can set off a frantic investigation to determine exposures and ensure immune status of staff and patients. As we recently reported, a single case of pediatric measles set off a staggering and expensive series of events at a hospital that included hundreds of blood tests, furloughed workers, and patient notifications. (See the October 2015 issue of Hospital Employee Health.)
Based on an analysis of national immunization survey data, the IDWeek study estimates that of 60 million U.S. children from infants to 17-year-olds, 8.7 million (12.5%) are susceptible to measles.1 This is primarily because they haven’t received the MMR vaccine, or they have received only one of the two recommended doses. (The first dose of MMR vaccine is recommended at 12 to 15 months of age and the second at 4 to 6 years old.) Of the total susceptible population, 6.7 million children are of an age recommended to be immunized for measles but have not been vaccinated. The remaining 2 million are under 1 year of age and thus not yet recommended for MMR, but it is important to include them because they are at greater risk of serious complications if they acquire measles, Bednarczyk said at an IDWeek press conference.
The data show a vaccination “bubble” or spike at around 5 years of age, suggesting school requirements have an impact, he said. However, many states allow exemptions for religious or personal reasons in addition to medical contraindications to the vaccine. Overall, the immunization rate trends upward with age, approaching the mid-90s in older teens who are more likely to have contact with more people. While that is generally good news, that still leaves one in four children three years and younger at risk of measles and even 5% of the 17-year-olds have not received any doses of the vaccine. A contributing factor is the anti-vaccine movement in the U.S. that has cast suspicion on all immunizations and linked the MMR shot erroneously with autism. Even if current immunization rates don’t further decline, there are pockets and clusters of vulnerable populations who can set off rapidly expanding measles outbreaks.
“As a pediatrician and a public health officer, it is frustrating to admit children to hospitals for a disease that is very preventable and generally we felt was gone,” said Matthew Zahn, MD, of the Orange County (CA) Health Care Agency.
Participating in the IDWeek measles discussion, Zahn said his county had 35 cases of measles at the beginning of 2015 as part of a large national outbreak that began at Disneyland.
“It was sobering to recognize that one exposure can cause so many cases around the country,” he said. “We have a significant number of kids in this country who are [non- or] under-immunized and it is terribly important that providers emphasize immunization.”
Currently, outbreaks typically burn out when they reach adult populations more likely to be immunized or have a history of natural infection. However, that firewall of sorts is subject to change as the demographic of non-vaccinators ages.
“There is a creeping nature to the problem in the sense that vaccine hesitancy is really coming of age to some degree,” Zahn said. “We now see kids of 15 or 18 years of age whose parents have not vaccinated them because they have concerns about the safety of the vaccines.”
- Bednarczyk R, Orenstein WA, Omer, S. Poster 1866. Estimating the Number of Measles-susceptible Children in the United States Using the NIS-Teen. Poster 1866. IDWeek Oct. 7-11 2015. San Diego, CA.
Employee health professionals should ensure the all staff have immunity to measles, as some 9 million U.S. children are susceptible to a virus that can cause chaotic outbreaks in healthcare facilities.
Subscribe Now for Access
You have reached your article limit for the month. We hope you found our articles both enjoyable and insightful. For information on new subscriptions, product trials, alternative billing arrangements or group and site discounts please call 800-688-2421. We look forward to having you as a long-term member of the Relias Media community.