More than 700 people have contracted the measles in the U.S. this year. It’s the worst outbreak since 1994. Here’s some common questions about the measles.
May 2, 2019
1). What’s measles and why is it dangerous?
The measles virus is one of the most contagious diseases known to humans. Spread by contact with an infected person, the virus will linger on surfaces for hours after the person has left.
“Measles has an attack rate of more than 90 percent,” says Dr. Moody, associate professor of pediatrics at Duke University. “Meaning that if you aren’t immune and you’re in the same room as someone carrying the virus, you’re almost certain to catch it.”
Measles starts with a fever, cough and runny nose. It progresses to a rash that starts on the face and neck and moves further down the body. Although most people recover from the measles, it can cause serious health complications. Measles can lead to pneumonia, brain swelling (which can cause intellectual disability and deafness) and even death. There’s also evidence to suggest that measles can suppress a person’s immune system years after they’ve recovered from the measles.
Moody says people romanticize measles as a mild childhood complaint, but overlook the seriousness of the infection, especially among infants and children.
2). How do you prevent or treat the measles?
There’s no treatment for measles, but a vaccine to prevent it has existed for decades. It works by introducing the body to a weakened version of the virus. As a result, the immune system develops antibodies that kick in to protect the person from the virus in the future.
The Centers for Disease Control and Prevention recommends children get two doses of the vaccine (called the MMR, because it includes the mumps and rubella vaccine) before they turn 6. Two doses ensure a 97 percent protection from measles. The vaccine is known to be safe, and most side affects are minor, like arm soreness or temporary fevers. Some studies show a small increase in risk (1 in every 3,000 to 4,000) for seizures among chilrden younger than 7. Multiple studies have shown no connection between vaccination and autism. The vaccine will provide immunity for decades, but adults can get a booster. Anyone born before 1957 most likely has been through the infection and has immunity.
The vaccine was invented in 1963. Before that, measles was ubiquitous and caused 400 to 500 deaths every year, according to the CDC. The vaccine’s introduction has led to a 99 percent reduction of measles cases, and in 2000 the virus was declared eliminated in the U.S.
“The reason this disease isn’t prevalent is that the population in the U.S. has mostly remained vigilant against it,” said Dr. Moody.
3). So why are we seeing an outbreak now?
Most outbreaks happen when travelers pick up the virus in places where the measles vaccine isn’t common, and bring it home to clusters of unvaccinated groups. The current outbreak is concentrated in close-knit groups of people who have opted out of the vaccine.
More than 400 of those cases are located in the Orthodox Jewish community in New York City, where many people have decided not to vaccinate their children. The outbreak started when a traveler brought the virus back from Israel. Another cluster is in Clark County, Washington, among a group of unvaccinated Slavic immigrants.
4) Is North Carolina at risk for an outbreak?
In North Carolina, vaccines are mandatory for children attending K-12 schools but state law allows people to opt out for religious or medical reasons. To get an exemption for religious reasons, parents must write a statement about their reasons and submit it to the school where their child attends in lieu of a vaccination record.
In the 2017-18 school year, 1.2 percent (or close to 1,500) of kindergarteners claimed a religious exemption to vaccines, according to data from the NC Department of Health and Human Services. The number of religious exemptions has steadily climbed since 2014, when it was only 0.8 percent.
"People with similar beliefs tends to cluster," said Moody. "That brings together a lot of susceptible individuals, and if one person bring its back to the group, it spreads quickly."
Certain counties and schools have a higher risk of an outbreak because of these clusters. In 2017, Buncombe County had a 5.7 percent religious exemption rate, the highest in the state. Last year, the county had its worst outbreak of chickenpox since the vaccine was introduced in 1995. The statewide rate is 1.2 percent.
Other western North Carolina counties also have higher than average rates of exemption, including Transylvania (4.7 percent), Watauga (4.7 percent), Polk (4.5 percent) and Clay County (4.3 percent).
However, health professionals say that if a large number of individuals have been vaccinated, then the population might have “herd immunity,” meaning that the disease won’t be able to spread easily. The more immunized people there are, the less likely the virus will infect the people that can’t or won’t get vaccinated.
5) Will we ever completely eliminate the measles?
Unlike viruses like HIV or Ebola, humans are the only animals to carry the measles, so we do have more control over it. But Dr. Moody says that unless the disease is eradicated on a global scale, exposure to it is only a plane ride away. The World Health Organization reports a 300 percent rise in measles cases in 2019 compared to 2018.
“And as long as there’s fertile ground for the virus—or concentrated groups of people who for personal reasons decide to not be immunized—then we’ll continue to see outbreaks,” said Moody.
Moody said when it comes to educating the public about vaccination, how you frame the conversation matters.
“In a country predicated on personal liberty, asking people to take on a small risk to protect the country at large can be tricky,” he said. “I like to focus on the data and point out that the risks of being vaccinated are far lower than the diseases themselves.”
Rossie Izlar is a digital producer on the UNC-TV Science team.