KEENE, N.H. — A New Hampshire child initially diagnosed with measles is not infected with the virus, state public health officials announced Thursday.
New laboratory test results suggest the child's symptoms were not caused by infectious measles, a highly contagious virus, and instead due to a reaction from the live-attenuated MMR vaccine, according to the New Hampshire Department of Health and Human Service's Public Health Services Division.
The public is not currently at risk for measles from the child and there is no contagious measles known to be circulating in the community, DHHS says, which says it is suspending additional public health interventions.
New Hampshire public health officials issued an advisory Sunday alerting those in the Keene area of a potential exposure to measles, after identifying a person who had been diagnosed then consulting with the CDC.
Early action procedures were initiated in the interest of public health to identify those potentially exposed with high risks of getting and spreading the virus.
DHHS says the child had been vaccinated several days prior to the start of their symptoms, which prompted immediate further lab testing to determine what type of measles strain had caused the initial positive lab test.
"This situation," state epidemiologist Benjamin Chan says, "serves as an important reminder that with measles circulating at unprecedented levels nationally, we all need to make sure we and our family members are protected and vaccinated against measles."
According to DHHS, the MMR vaccine is a live-attenuated vaccine – made using a weakened virus like some influenza vaccines – intended to build up a person’s immunity. Like all vaccines, it says, there can be side effects associated with the vaccine.
About 5% of individuals vaccinated with the MMR vaccine develop a fever and rash reaction, the department says. These reactions happen because the body is responding to the vaccine by making protective virus-fighting antibodies against the harmless vaccine virus.
More serious or extensive reactions that resemble a real measles virus infection, as was seen in this child, are very rare, according to DHHS. Scientific literature, it says, has found no confirmed cases of human-to-human transmission of the vaccine strain of the measles virus.
Those with questions or concerns for DHHS can call 603-271-9461 from 8 a.m. to 4 p.m., or toll-free for state residents at 1-800-852-3345 ext. 9461.
The following information is provided by New Hampshire DHHS:
Measles is caused by a virus that is passed from person-to-person through the air when someone with the disease sneezes, coughs, or talks. The virus can remain infectious in the air for up to two hours after an infected person leaves the area. It is very easy for individuals who have not received the measles vaccine to contract it from someone else. The incubation period for measles from the time of exposure is 7 to 21 days, typically 2 weeks. Symptoms of measles infection usually begin with high fever, cough, runny nose, and conjunctivitis several days prior to developing a body rash.
In order to protect the health of the community and individuals who may not be able to receive the vaccine, NH DHHS recommends that all people review their vaccination status with their healthcare providers to ensure adequate immunity to measles. The measles vaccine (MMR vaccine) is very safe and effective, and approximately 99% of individuals who receive two doses of the vaccine develop immunity to measles.
For more information about measles prevention, download the DHHS Measles Fact Sheet at www.dhhs.nh.gov/dphs/cdcs/documents/measles.pdf, visit the DHHS Immunization Program webpage at www.dhhs.nh.gov/dphs/immunization/index.htm, and visit the Centers for Disease Control and Prevention website at www.cdc.gov/measles/index.html.
