What to know about getting vaccinated for measles

A child in Suffolk County is the third person statewide to be infected with the highly contagious disease. On Friday, the Centers for Disease Control and Prevention reported 222 measles infections in the United States. Most cases are in Texas but some measle infections have been confirmed in other locations, including two people in New York City.

Health experts say low vaccination rates are fueling outbreaks of the contagious disease that was considered to be eliminated 25 years ago. But people who were vaccinated decades ago as young children are wondering if their immunity is still strong. Newsday asked infectious disease specialists to weigh in.

What exactly is measles and how does it spread?

Measles is a highly contagious disease that can cause serious illness including pneumonia and encephalitis. Children under the age of 5 are at a high risk of complications, according to the CDC. It is airborne and an infected person can easily spread it to others when they cough or sneeze.

"It’s the most contagious disease out there that we know of," said Dr. Kawsar Talaat, infectious diseases and international health expert at Johns Hopkins Medicine. "If a child with measles walked into an elevator and you walked into the same elevator a couple of hours later, you could get measles ... the virus lives in the air, lives in the environment for hours."

In some cases, measles can be a fatal infection.

What are the symptoms of measles?

Symptoms include high fever, cough, runny nose, and red, watery eyes, according to the CDC. But the most commonly known measles symptom is the red spotty rash that covers a person’s body.

When do you get vaccinated against measles?

The measles vaccine was developed in the early 1960s and originally administered with one dose. In 1989, several experts including the American Academy of Pediatrics recommended a second dose after there were outbreaks among vaccinated school-age children. The first dose is given between 12 and 15 months of age and the second between 4 and 6 years of age.

"One dose of the measles vaccine provides immunity to about 93% of people," said Dr. Andrew Handel, a pediatric infectious disease expert at Stony Brook Medicine. "About 7% of people who were immunized just didn't develop the antibodies for whatever reason and now we give a second dose. This gives a bit of a boost to the people who are already immune but also to those 7% of kids who didn't develop an antibody response the first time around ... this gets to about 98% of immunity."

Who does not need to be vaccinated?

"If you were born before 1957, you are considered immune just based on epidemiology," said Dr. Bruce Farber, chief of public health and epidemiology at Northwell Health. "If you have received two doses of the vaccine at any time, the live vaccine, you are immune."

I was vaccinated in the 1960s. Do I need another shot to stay immune?

A version of the vaccine using inactivated (killed) measles was given to some people between 1963 and 1967, according to the CDC, and was not effective. A person who received that vaccine may want to have a blood test to check if they have immunity or get one additional shot, but should have a conversation with their doctor first to see if it is necessary, Farber said.

But not everyone vaccinated during that time received that specific version of the vaccine.

"The overwhelming majority of people who have received their vaccine are immune and even people who've gotten one vaccine are most likely immune," Farber said. "If you are living in New York now and in that age group, I probably would not go out and get a booster unless there is a reason. On the other hand if you have only gotten one vaccine and you’re going to Texas, get another one."

By Lisa L. Colangelo

lisa.colangelo@newsday.com@lisalcolangelo

Lisa joined Newsday as a staff writer in 2019. She previously worked at amNewYork, the New York Daily News and the Asbury Park Press covering politics, government and general assignment.