Norovirus

Norovirus (stomach flu) infection is caused by a group of viruses called Noroviruses. These viruses are found worldwide, including in New Brunswick. They commonly cause outbreaks in schools, childcare centres and residential facilities. These viruses cause diarrhea illness and are passed in feces or vomit. This flu is not the same as the “flu” or influenza, a respiratory illness caused by the influenza virus.

Clinical diagnosis is based on an assessment of clinical symptoms by a health-care provider and laboratory testing of a stool sample. 

Symptoms usually appear suddenly, about 24 to 48 hours after a person becomes infected with the virus. Most people who become ill have nausea, vomiting, diarrhea and stomach cramps. They may also have a low-grade fever, chills, headache, muscle aches and fatigue. Symptoms usually last eight to 12 hours, and people normally recover in 48 hours.

Noroviruses are passed in feces and vomit from infected people and spread very easily. The virus is spread by person-to-person contact. 

Some examples of how the virus can be spread include: 

• inadequate washing of hands by an infected person prior to food preparation 
• sharing food or eating utensils with an ill person
• touching surfaces or objects contaminated with norovirus (like door handles)

Anyone exposed to the virus can become infected. Young children, the elderly and people with weakened immune systems are at a greater risk of developing more serious illness. Outbreaks may occur at any time of the year and are common within families and group settings where people are in close contact with one another (nursing homes, hospitals, childcare centers, schools and residential living facilities)

Stay at home if you have symptoms and are feeling ill. People with diarrhea should drink a lot of liquids to avoid dehydration and practice good personal hygiene, such as hand washing. Avoid preparing food for others while you have symptoms and for 48 hours after you recover. Consult your family doctor for advice and treatment if you have bloody or severe diarrhea, as prescription medicines can be used.

In an outbreak situation, health-care providers and laboratories are required to report cases to Public Health. Public Health staff may then investigate to find out how the infections occurred, identify other people who may be at risk of infection, implement enhanced public health measures and provide advice as necessary. 

This may include exclusion of infected workers in high-risk occupations like persons involved in food handling, direct patient care and care of the young or the elderly. As a control measure, infected children participating in daycare may also be requested to exclude. 

Use good environmental management. Flush or discard any stool in the toilet and clean surrounding area using hot water and detergent. A chlorine-based disinfectant is recommended. 

Practice good personal hygiene. Wash hands thoroughly with soap and water after using the toilet or changing a diaper, after handling animals or contact with animal feces, after handling raw poultry and meats and before preparing or eating food. 

Take food safety precautions. Wash or peel all raw vegetables and fruits before eating. Thoroughly cook all meats (meat, poultry and seafood). Prevent contact of cooked foods with raw poultry and other meat. Drink and eat only pasteurized dairy products (milk, cheese, yogurt and ice cream). 

Drink properly treated water. Avoid swallowing recreational waters from swimming pools and hot tubs. Do not drink untreated surface water from lakes or streams. Test private well drinking water regularly (once or twice per year).

For additional information, contact your health-care provider, local Public Health office or Tele-Care 811.