Gastroenteritis

• Viral gastroenteritis is an infection of the the stomach and intestines by viruses. The most common cause is the Norwalk virus. Symptoms include vomiting, diarrhea, malaise and, in some cases, a low-grade fever.
  
  

Infectivity

• Norwalk viruses are very infectious. According to CDC, it takes only 10 viral particles to infect a susceptible person. The virus is coated in protein, making it resistant to drying and alcohol-based cleaners. This is why proper environmental cleaning is key.
  
  

Surfaces

• The survival of the virus on surfaces depends on the ambient temperature and the type of surface. In a study by the Bureau of Microbial Hazards of the Canadian Health Ministry, Norwalk virus was recovered from refrigerated food up to seven days after contamination. It survived freezing temperatures, and smooth, metal surfaces did not promote the virus' survival beyond three days.
  
  

Cleaning

• CDC recommends that a 1:50 ratio of bleach to water be used to clean contaminated surfaces. If an item cannot be cleaned with chemicals, 160-degree heat can be used to disinfect those items.
  
  

Hygiene

• Hand sanitizers do not work against Norwalk viruses. Hand washing is the best way to clean and disinfect hands to avoid infection after handling contaminated food or surfaces.