LONDON, ONT. -- London residents are being urged to check their immunizations after multiple mumps cases have surfaced connected to downtown bars.

So far, the Middlesex-London Health Unit (MLHU) says two cases have been identified among people who visited bars in the city's core.

Dr. Alex Summers, associate medical officer of health with the MLHU, said in a media release, “We want to get the word out to people who may have headed downtown to enjoy the nightlife recently, that they may have been exposed to the mumps virus unknowingly."

The two known cases are connected, but the MLHU say it is unclear if there could be more.

Summers added that anyone who has been at a downtown bar should watch themselves for symptoms.

"Anyone who develops a fever, headaches, muscles aches, fatigue and or swelling or pain near the jaw or cheeks should stay home and contact their health care provider first before seeking care.”

People are also reminded to check that their immunizations are up-to-date.

Anyone between 18 months and 50 years old should have received two measles, mumps, rubella (MMR) vaccinations.

Those born between 1970 and 1991 should pay extra attention, as a single dose for children was routine at that time.