Hundreds of students and staff at California State University in Los Angeles, above, and the University of California at Los Angeles, have been placed under quarantine because they may have been exposed to measles. (Damian Dovarganes/AP)

Recently, my family was presented with an opportunity to make a once-in-a-lifetime trip to a country in Southeast Asia. We mapped out our flights and chose a hotel. Then, alarmed by the recent resurgence of measles, we checked the website of the Centers for Disease Control and Prevention — and learned there had been several reported cases of measles in the country.

The trip’s dates are nonnegotiable, and my son will be two weeks shy of 6 months old — the earliest an infant can receive the MMR vaccine that protects againstmeasles.

I’m sure other parents with babies — or with older children who could not be vaccinated because of medical treatment or a weakened immune system — are facing similar dilemmas. As the summer travel season nears and the outbreak continues in the United States and abroad, what do parents need to know to keep their children safe?

The situation

As of April 25, the number of measles cases reported in the United States hit 695 — the highest number in any year since the disease was eliminated in the country in 2000, the CDC said. Worldwide, the number of cases in the first three months of 2019 were triple the amount recorded in the first three months of 2018, according to the World Health Organization.

Travelers to countries with outbreaks — including Ukraine, Israel and the Philippines — brought the disease back to the United States and infected others who were not vaccinated, said Kristen Nordlund, a CDC spokeswoman. A large number of cases are concentrated in Washington state and New York City.

Last week, after a student at the University of California at Los Angeles and another student at California State University at Los Angeles were diagnosed with measles, hundreds of students, faculty and staff members at the two schools were quarantined until they could provide proof of immunization. Los Angeles County has had five confirmed cases of measles, and travelers have been warned several times about possible exposure at Los Angeles International Airport.

“The measles outbreak is kind of a sad story because it’s completely preventable,” said Sanjay Jain, director of the Center for Infection and Inflammation Imaging Research and a professor of pediatrics at Johns Hopkins University School of Medicine. “You have a pretty efficacious vaccine that works pretty well. People are just misinformed.”

Vaccination schedules

In a normal scenario, children first receive the MMR vaccine when they are between 12 and 15 months old. A booster is given when the child is between 4 and 6 years old.

The CDC recommends that babies between 6 months and 11 months old receive the vaccination before international travel or if they are in a community that is affected by an outbreak.

Infants younger than 6 months are not given the MMR vaccine, Jain said, because it is believed that there are still antibodies present that have been passed on from the vaccinated mother in the third trimester. Because the MMR shot contains a live virus, the antibodies would make the vaccine ineffective.

And if a child does receive the vaccine at 6 months, it’s not guaranteed that it would be as effective as it is if it’s administered after the child’s first birthday. “It’s not like at 6 months, all the antibodies go away,” Jain said. “It’s not a magical number.”

Gauging the risk

When Courtney Correia, an American living in Japan, traveled with her 4-month-old son to the U.S. Embassy in Tokyo recently to apply for his passport, she worried about his health. Japan is in the middle of its worst measles outbreak in a decade, and her son is too young to be vaccinated.

“I think about the measles every time I get on the train,” Correia said. “Obviously we want to protect our babies as best we can.”

She plans to fly this month from Yokosuka, Japan, where her husband is stationed, to the United States to introduce her family to the baby, whose name is Rory. “Flying with an infant is stressful enough, never mind worrying about all the germs,” Correia said.

Before buying her tickets, she talked with her doctor, who eased her worries a bit by reminding her of the antibodies that had been passed on to the baby during pregnancy. She and her husband agreed they were comfortable with the amount of risk associated with the trip.

Jain suggests researching where you are going by checking for travel warnings and outbreaks in the area. Other factors to take into consideration are whether your baby was born full-term and is healthy.

“I think you have to think very, very hard about it,” Jain said. “Common sense would be critical.” Jain has a 6-week-old and has decided to not travel outside the United States this summer.

If a child has not been vaccinated, is older than 12 months and international travel is planned, the initial MMR shot and a booster can be given within 28 days of each other. Traces of immunity are detectable within a few days, according to the CDC, and a person can be fully protected within two to three weeks.

If a child cannot be vaccinated due to an immunosuppression, the CDC says, travel should be delayed because the child is more likely to experience severe complications if they get the measles.

Protecting your child when travel is necessary

Vaccination is the easiest way to protect your child before traveling, but if the baby is too young to receive the vaccination or wasn’t able to as an infant, there are a few things you can do to help minimize the risk of infection.

The same preventive steps that are taken during cold season apply here. The American Academy of Pediatrics suggests washing your hands for at least 20 seconds, avoiding crowded places and keeping your child away from people who are visibly sick.

Jain also said putting a cover on an infant car seat and surgical masks on older children could help protect againstmeasles when in public.

Mothers who are nursing should consider continuing to do so through the trip, because breast milk contains antibodies. “A breast-fed baby is probably more protected than a non-breast-fed baby,” Jain said.

How to know and what to do if your child has been infected

Even after a person is infected with measles, they remain asymptomatic for a seven-to- 14-day incubation period. The first visible symptoms of the measles may seem like a cold. There could be a high fever, runny nose, cough and conjunctivitis, or pinkeye. White spots may appear inside the mouth a couple days later, the CDC says. Three to five days after symptoms start, a rash of flat red spots will appear on the face and move down the body. The spots may have raised bumps.

These may seem like mild symptoms, but complications can occur. According to the CDC, measles can cause ear infections, which can lead to permanent hearing loss in some children. About 5 percent of children who are infected withmeasles contract pneumonia; this is the leading cause of death among young children with measles. About 1 child out of every 1,000 with measles will develop encephalitis (swelling of the brain) that can result in deafness or intellectual disability. And out of every 1,000 children infected with measles, 1 or 2 will die.

Once symptoms occur, parents should call a doctor to make a plan for when and how to be evaluated. To prevent the spread of infection to others, the CDC recommends wearing a mask in public and not showing up unannounced at a doctor’s office.

Once it is confirmed that your child has measles, it is advised for them to stay home for four days after the rash appears.

Our decision

As with most parenting decisions, figuring out whether to travel during the measles outbreak isn’t cut and dried.

My husband and I went back and forth about whether to take our trip, but we recently decided to book the flights after weighing all the risks. Our destination has no travel notices from the CDC and our son, who was born on his due date, is a robust, chunky baby. Our short time of being stationed overseas is quickly coming to an end, and with it, the opportunity to experience parts of Asia many Americans never will.

Gahan is a writer based in Japan. Follow her on Twitter: @VPMaryBeth.