By Nadeane Brull, Chatham-Kent Public Health Unit
Norovirus is a virus that causes gastroenteritis. It can be commonly referred to as winter vomiting disease or the stomach flu. Using the term stomach flu is misleading in that having norovirus is unrelated to the influenza virus that causes respiratory illness and is generally called the flu. Symptoms of norovirus include sudden onset of vomiting, diarrhea, nausea, low grade fever and abdominal cramps.
Norovirus is a common virus and affects all age groups of people. However, young children, elderly people and those with underlying medical conditions tend to experience more severe symptoms. It is transmitted by contaminated food and water, person to person direct contact and contact with contaminated surfaces. Most foodborne outbreaks occur when an infected food handler contaminates the food being served. Shellfish harvested from contaminated water can also transmit norovirus.
Norovirus is a hardy virus that can survive on environmental surfaces for several weeks. It can also be spread through small droplets that are generated by vomiting. Symptoms can occur as soon as twelve hours after an exposure but the incubation period is usually 24-48 hours.
Norovirus infections are typically self-limiting and symptoms usually resolve within one to two days. There is no specific treatment, but, fluid and electrolyte replacement is crucial to prevent dehydration from frequent vomiting and diarrhea.
Norovirus is very contagious as the infective dose to make a person ill is very small. It often spreads quickly in enclosed settings such as schools, nursing homes, daycare centres and cruise ships.
Prevention of norovirus transmission can be challenging, however adequate hand hygiene is essential for preventing illness. It is especially important to preform hand hygiene prior to eating and preparing food and after toileting and changing diapers. Safe food handling including washing fruits and vegetables prior to consumption and cooking shellfish thoroughly can help prevent norovirus. It is also important to clean and disinfect high touch surfaces frequently. Bleach is the recommended product to use on surfaces to eliminate norovirus. The recommended effective strength for the bleach solution is one cup bleach to nine cups water.
For more information please contact Chatham-Kent Public Health Unit at 519.355.1071.
