Multiple measles outbreaks causes CDC to issue warning

The CDC is issuing a warning following 23 confirmed cases of measles between December 1, 2023 and January 23, 2024.

The notification, sent via email to healthcare providers, noted the cases have been reported in Delaware, New Jersey, Pennsylvania and the Washington, D.C. area. Amongst the cases, seven are from international travelers. There have been no reported cases of measles in North Carolina so far this year, nor were there any in 2023.

"Of all the current infectious diseases we have, measles is the most infectious one, substantially more infectious than flu, COVID or RSV, meaning if I am infected and everyone around me were susceptible, something like 15 to 18 people around me would become infected. It's airborne. The virus hangs around the air for a very long time. In fact, there are cases where the patient with measles left a room in the emergency department and up to two hours later, people going in that room acquired measles," said Dr. David Weber, Medical Director of Department of Infection Prevention at UNC Medical Center.

Despite being declared eliminated by the US in 2000, there have been pockets of measles outbreaks in the years since, notable in 2019 when there were more than 1,100 reported cases.

"The more infectious the disease is, the higher percentage of the population that has to be immune either from vaccine or disease. Well, we haven't had the disease here in the U.S. in a long time. So more than 95% of the people have to be immune by a vaccine, and we know that that number in many locales is below 95%," Dr. Weber said.

According to NCDHHS, in the 2022-2023 school year, 94% of the state's kindergarteners were reported up to date on their MMR vaccine, slightly above the national rate of 93.1%. The MMR vaccine, which covers measles, mumps and rubella, is a two-dose regimen. The CDC recommends a child receives their first dose between 12 and 15 months, and second dose between 4 to 6 years old.

"If you've had both doses and had a normal immune system, it's 99% effective in preventing infection," said Weber.

According to NCDHHS data, across kindergartners in public schools last academic year these were the rates for required vaccinations in each county:

• Alamance: 97.67%
• Chatham: 96.47%
• Cumberland: 91.19%
• Durham: 82.24%
• Harnett: 94.04%
• Johnston: 96.9%
• Nash: 88.77%
• Orange: 96.83%
• Person: 100%
• Pitt: 96.41%
• Vance: 96.3%
• Wake: 96.01%
• Wilson: 95.13%

The MMR vaccine is a required vaccination for public school students in North Carolina. The above figures include students who received religious and/or medical exemptions, and is comprised of information within 30 days of enrollment. Because of that, the true vaccination rates could be higher if students received their vaccinations or submitted their records after that time period.

The CDC reports the vaccine takes about two to three weeks to offer full protection, and recommends people traveling internationally are fully vaccinated at least two weeks before departing.

For people who are not vaccinated or highly immunosuppressed, the recent outbreak is cause for attention.

"A lot of the outbreaks occur where there's a lot of mixing, so particularly high schools and colleges are vulnerable, where you might have a few susceptible (people) and people are talking to a lot people each day," said Weber.

The CDC reported North Carolina experienced the 7th largest jump in MMR vaccination rates between the 2020-2021 and 2021-2022 school years, including the biggest jump of any state in the southeast.

Children who are uninsured can be vaccinated at low or no cost through the state's Vaccines for Children program, which is available to kids through 19 years old.

"While statewide coverage remains high in North Carolina, it is important to note that coverage levels vary locally, with some counties and school settings having higher than average exemption rates that leave them more susceptible to a measles outbreak," said an NCDHHS spokesperson.

Symptoms of measles include high fever, cough, runny nose, conjunctivitis, and rash.

"Like flu, RSV, and COVID, you become infectious before showing any symptoms or signs," said Weber.