That brings the total in the last few weeks to 17 children, ranging in age from seven months to four years old.
According to the Department of Health, three infections, including the initial case, were acquired by children who visited Israel, where there is an outbreak of measles. The disease was then transmitted in schools to children who were either unvaccinated or incompletely vaccinated.
Officials note that there have been no deaths associated with these new cases, though complications have included hospitalization.
“The increase in measles cases in Orthodox Jewish communities of Brooklyn demonstrates the importance of getting children vaccinated on time to prevent measles and not put other children at risk,” said acting Health Commissioner Oxiris Barbot in a statement.
To increase awareness, the department sent notifications to schools, health care providers and hospitals with large Orthodox Jewish populations. The city is also placing ads in newspapers and distributing posters to care providers.
The outreach has led to an increase in vaccination rates since the outbreak, officials said, but more children should receive the vaccination.
The Health Department recommends the measles, mumps and rubella (MMR) vaccine for all children at 12 months, and a second dose between ages four through six. The two doses are required to attend kindergarten through 12th grade.
They also recommend that all people traveling abroad, including infants ages six to 11 months, should be vaccinated before leaving.
“If your child develops a rash or fever, contact your physician immediately,” Barbot said, “and keep them home from school or child care.”
If a student has measles, all unvaccinated students, including those with a medical or religious exemption, will be excluded and unable to attend daycare or school for 21 days after their last exposure, according to officials.
Measles is highly contagious, and young children, the immuno-compromised and non-immune pregnant women are at high risk for severe complications, the Health Department said. The disease is transmitted by airborne particles, droplets and direct contact with an infected person.
The disease manifests through a fever and rash, usually starting in the face and proceeding down the body. It can last several days.
In addition to an outbreak in Israel, Europe has faced a surge in cases of measles as well. In 2018 alone, there have been 41,000 cases of measles leading to 40 reported deaths.
Rabbi David Niederman, president of the UJO of Williamsburg and North Brooklyn, said in statement that parents need to ensure their children are vaccinated.
“Thankfully, close to everyone in the community understands and takes very seriously their vaccination obligations,” he said. “The current outbreak is a risk to the health of the children in our community, and it is incumbent for everyone to have their children vaccinated.”