That shelter is the Hall Street migrant shelter in Clinton Hill, Brooklyn.
Health officials are going through their contact tracing process trying to figure out who has been exposed.
The pool is limited to the first floor of the shelter where the two adult-positive residents stayed.
Anyone who doesn't have documented vaccination will be tested for immunity.
Anyone who isn't immune will have to quarantine for 21 days.
According to the health department, there are 11 cases of measles in New York City as of July 12.
There was only 1 confirmed case in the city last year.
The Hall Street migrant shelter has been a point of contention for Clinton Hill residents who have complained of an uptick in trash, noise and street homelessness under the Brooklyn-Queens Expressway.
The measles cases could add to those concerns because of how contagious it can be.
The good news is that while contagious, experts say the risk to the community is low as most New Yorkers are vaccinated against it.
If you are not vaccinated, you are urgent to contact your doctor.
For additional information about measles, go to NYC Health Department.
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