In a news release, the city said there is a cluster of cases among unvaccinated residents.
PHILADELPHIA (WPVI) -- There are now six locations in Philadelphia where people may have been exposed to measles since late December, according to the city's health department said.
That includes five locations announced Thursday in addition to one that was announced just two days before Christmas.
In a news release, the city said there is a cluster of cases among unvaccinated residents, which originated at Children's Hospital of Philadelphia.
As of January 5, officials say there are six confirmed cases and three presumed cases.
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On Thursday, officials confirmed several cases were reported after one of the initial cases went to day care instead of following the quarantine protocol.
"The Health Department is strongly recommending that anyone who may have been exposed to measles should quarantine themselves by staying home and away from others," city officials said.
If you were at any of the below sites on the days listed, you may have been exposed to measles:
Jefferson Health building at 33 S 9th/833 Chestnut St
-Exposures took place on December 19 between 2 p.m. and 5:30 p.m.
Multicultural Education Station Day Care at 6919 Castor Ave
-Exposures took place on December 20 and 21
Children's Hospital of Philadelphia Emergency Room at 3401 Civic Center Blvd
-Exposures took place on December 28
St. Christopher's Hospital for Children Emergency Department
-Suspected exposures may have happened overnight December 30 - December 31 mid-afternoon
St. Christopher's Hospital for Children inpatient unit 5 North
-Suspected exposures may have happened between December 31 and January 3
Nazareth Hospital Emergency Room
-Suspected exposures may have happened on December 31 and January 2
Health officials say if you were in one of those buildings on the dates listed and are not immune to measles (including infants under 12-15 months, who typically have not yet been vaccinated):
Measles is a virus that spreads easily, according to the Philadelphia Department of Public Health.
"Measles is highly contagious, about 90% of people who are not vaccinated, who are exposed, will get measles," said Philadelphia Health Commissioner Dr. Cheryl Bettigole.
Measles symptoms include fever, runny nose, cough, and puffy eyes, followed by a rash. In some cases, it can be a serious infection that leads to pneumonia, brain infection, and death.
"If you have not been vaccinated against measles or have not vaccinated your children who are 12 months of age or older, please reach out to your healthcare provider to do so immediately. If you or your child has been exposed to measles, please follow public health guidance to avoid exposing additional children," Bettigole said in a statement.
For more information on how to get a vaccine, visit this page on Phila.gov.