Waterloo-Dufferin-Guelph Public Health officials are asking anyone who ate at Marj's restaurant in Alma between Jan. 2 and Jan. 20 to contact them, as they may be at risk for hepatitis A exposure.

Dr. Nicola Mercer, the medical officer of health and CEO of Waterloo-Dufferin-Guelph Public Health, says it is important that anyone who may have eaten at the restaurant get in touch quickly, as there is a limited window of opportunity for the hepatitis A vaccine to work effectively.

"The vaccine works best if you get your shot within 14 days of your exposure," said Dr. Mercer.

"So we are asking everybody to call us because we want to interview them to see what their exposure is and the timeframe, and then we will be providing immunizations to those people who have had exposure to hepatitis A by eating at the restaurant."

Mercer says symptoms can develop 15 to 50 days after exposure to the virus and can range from mild to severe. Signs can include fever, loss of appetite, fatigue, nausea, vomiting, dark urine and yellowing of the skin. However, hepatitis A is rarely fatal and is not known to cause long-term infection.

As for how the restaurant was flagged for possible hepatitis A exposure, Dr. Mercer says it was brought to public health's attention when an employee who handled food at the restaurant was diagnosed by a family doctor.

"The answer is not very pleasant," said Dr. Mercer. "It's actually a fecal-oral transmission which means that an individual after using the bathroom doesn't wash their hands appropriately, that you can contaminate the food that you are preparing."

Wellington-Dufferin-Guelph Public Health is asking anyone who believes they may be at risk to call 1-800-265-7293 or visit their office at 474 Wellington Road #18, Suite 100 in Fergus between 8:30 a.m. and 4:30 p.m. on Jan. 23.