A new case of hepatitis A has been confirmed at a Chinese food restaurant in Kensington, and the city health department is urging people who purchased food there between July 21 and Aug. 6 to be vaccinated.

The Philadelphia Department of Public Health on Friday said a worker at Imperial Kitchen, 3164 Frankford Ave., was confirmed to have hepatitis A. The liver infection is spread through oral contact with infected feces — usually when an infected person does not thoroughly wash their hands after using the bathroom and then prepares food.

People who ate at the restaurant but have already received two doses of the vaccine or who have had hepatitis A in the past do not need to be vaccinated.

The city health department on Aug. 1 declared a public health emergency in response to an outbreak of hepatitis A, which has sickened more than 150 people in Philadelphia since the beginning of the year.

The city typically reports fewer than six cases a year.

About two-thirds of this year’s cases have occurred among people who use drugs, who are at higher risk for the disease, according to the health department. People experiencing homelessness, men who have sex with men, and people who are in jail or recently released are also at heightened risk.

Symptoms of the virus include vomiting, diarrhea, and abdominal pain. Most cases can resolve without treatment, but the infection can be dangerous for older adults, individuals with liver disease, and those with other medical conditions.

The most effective way to protect against contracting hepatitis A is to get vaccinated.

The health department will offer free vaccines at McPherson Square Park on Tuesday, Aug. 20, and Thursday, Aug. 22, from 10 a.m. to 2 p.m.

People can also consult their doctor or pharmacy for a vaccine.

Check the city’s map, available online at www.phila.gov, to find where to get a vaccine near you or call the health department weekdays at 215-685-6741.