Public Health Preparedness
Norovirus is a virus that causes the "stomach flu," or vomiting and diarrhea, in people. The illness is usually brief, with symptoms lasting only one or two days.
Norovirus illness usually begins 24-48 hours after exposure, but can appear as early as 10 hours after exposure.
How serious is norovirus disease?
Norovirus disease is usually not serious, but people may feel very sick. Most people get
better within one or two days, and have no
long-term health effects from the illness.
Sometimes people are unable to drink
enough liquids to replace what they lose from vomiting and diarrhea, and they can become dehydrated and need to see a doctor. This
problem usually occurs only among the very young, the elderly, and persons with weakened immune systems.
How is norovirus spread?
Norviruses are very contagious and spread
easily from person to person. The virus is
found in the stool and vomit of infected people. People can become infected in several ways,
including eating food or drinking liquids that are contaminated by infected food handlers, touching surfaces or objects contaminated with norovirus and then touching their mouth before handwashing, or having direct contact with
another person who is infected and then touching their mouth before handwashing. Persons working in day-care centers or nursing homes should pay special attention to children or
residents who have norovirus illness. This
virus can spread quickly in these places.
How long are people contagious?
People infected with norovirus are contagious from the moment they begin feeling ill to at
least three days after recovery. Some people may be contagious for as long as two weeks
after recovery. Therefore, good handwashing
is important. Persons infected with norovirus should not prepare food while they have
symptoms and for three days after they
recover. Infected people do not become
long-term carriers of norovirus.
Who gets norovirus infection?
Anyone can become infected with these viruses. Because there are many different strains of
norovirus, norovirus infection and illness can
re-occur throughout a person's lifetime.
What treatment is available for people with norovirus infection?
Currently, there is no specific medication or vaccine for norovirus. Norovirus infection
cannot be treated with antibiotics. By drinking fluids, such as juice or water, people can
reduce their chance of becoming dehydrated. Sports drink do not replace the nutrients and minerals lost during the illness.
Do infected people need to be excluded from school, work or daycare?
Since the virus is passed in vomit and stool,
children should not go to daycare or school while they have diarrhea or vomiting. Once
illness ends, children can return to daycare,
but handwashing must be strictly monitored. Persons who work in nursing homes, take care of patients, or handle food should stay out of work until at least three days after symptoms end.
Can norovirus infections be prevented?
You can decrease your chance of coming in contact with noroviruses by:
- Frequently washing hands with warm water and soap
- Promptly disinfecting contaminated surfaces
- Washing soiled clothing and linens
- Avoiding food or water from sources that may be contaminated