Outbreaks and the role of EHOs

An outbreak occurs when more than two people have the same illness that can be linked back to one source or cause. Environmental Health Officers (EHOs) respond to reports of outbreaks around food or water borne illness as well as Norovirus. EHOs will contact the ill individuals to perform a follow-up about food history, water source, events attended and more to determine a possible source or cause. Laboratory confirmation is necessary to determine the disease causing organism and to link cases in an outbreak. Knowing what organism is causing the illness also aids in determining what prevention measures are necessary to limit further spread.

When an outbreak is linked to a facility such as a care home, child care facility, school, etc., the EHO will do an onsite investigation and identify what control measures should be put in place. If an outbreak is linked to a water system, a Boil Water Advisory or Do Not Use notice may be issued. If the outbreak is linked to a food service establishment, an investigation will be conducted and necessary control measures implemented. If the outbreak is linked back to one food source, a recall will be initiated by the Canadian Food Inspection Agency (CFIA).

Norovirus

Noroviruses are a group of viruses that cause gastroenteritis in humans, the symptoms of which include nausea, vomiting, diarrhea, abdominal cramps, chills, body aches and fatigue. The symptoms usually appear suddenly 24-48 hours after exposure, and last approximately 24-60 hours. It is highly contagious and transmission is primarily through the fecal-oral route following direct contact with a person who is, or has been, recently ill. Fecal-oral transmission happens through contaminated hands-to-mouth, food-to-mouth, or fomites(objects)-to-mouth resulting in ingestion of the viruses. Noroviruses are responsible for a large number of outbreaks each year, particularly in winter months when people spend more time indoors and in close quarters.

The best way to protect yourself against a Norovirus illness is to wash your hands regularly, especially before eating, and for sick people to stay home while ill.