Guidelines for Norovirus Prevention and Control in Long Term Care Facilities

Noroviruses are the most common cause of epidemic gastroenteritis disease worldwide and are frequently associated with outbreaks in Long Term Care Facilities (LTCF). The following guidelines have been developed with the intended goal of interrupting transmission and preventing spread to others when Norovirus is suspected in a LTCF. II. TRANSMISSION Noroviruses are highly contagious with as few as 100 virus particles thought to be sufficient to cause infection. Noroviruses are transmitted primarily through the fecal-oral route, either by direct person-to-person spread or fecally contaminated food or water. Noroviruses can also spread via a droplet route from vomitus. These viruses are relatively stable in the environment and can survive freezing and heating to 60°C (140°F). In healthcare facilities, transmission can additionally occur through hand transfer of the virus to the oral mucosa via contact with materials, fomites, and environmental surfaces that have been contaminated with either feces or vomitus. III. CLINICAL FEATURES Noroviruses cause acute gastroenteritis in persons of all ages. The illness typically begins after an incubation period of 12 – 48 hours and is characterized by acute onset of non-bloody diarrhea, vomiting, nausea and abdominal cramps. Symptomology is variable and persons may experience only vomiting or diarrhea. Low-grade fever and body aches may be associated with infection, and thus the term “stomach flu ” is often used to describe the illness. However, there is no biologic association with influenza. Although symptoms can be severe; they are typically self-limiting and resolve without treatment after 1–3 days in otherwise healthy persons. However, more prolonged courses of illness lasting 4–6 days can occur, particularly among young children, elderly persons, and hospitalized patients. Norovirus-associated deaths have been reported among elderly persons and in the context of outbreaks in LTCF