"Stomach Flu" or Viral Gastroenteritis
What is viral gastroenteritis?
means inflammation of the stomach and small and large intestines.
Viral gastroenteritis is an infection caused by a variety of viruses
that results in vomiting or diarrhea. It is often called the "stomach
flu," although it is not caused by the influenza viruses.
What causes viral gastroenteritis?
Many different viruses can cause gastroenteritis, including rotaviruses,
adenoviruses, caliciviruses, astroviruses, Norwalk virus and a group
of Noroviruses. Viral gastroenteritis is not caused by bacteria
(such as Salmonella or Escherichia coli) or parasites (such as Giardia),
or by medications or other medical conditions, although thesymptoms may be similar. Your
doctor can determine if the diarrhea is caused by a virus or by
the symptoms of viral gastroenteritis?
The main symptoms of viral gastroenteritis are watery diarrhea and
vomiting. The affected person may also have headache, fever, and
abdominal ramps ("stomach ache"). In general, the symptoms
begin 1 to 2 days following infection with a virus that causes gastroenteritis
and may last for 1 to 10 days, depending on which virus causes the illness.
Is viral gastroenteritis
a serious illness?
For most people, it is not. People who get viral gastroenteritis
almost always recover completely without any long-term problems.
Gastroenteritis is a serious illness, however, for persons who are
unable to drink enough fluids to replace what they lose through
vomiting or diarrhea. Infants, young children, and persons who are
unable to care for themselves, such as the disabled or elderly,
are at risk for dehydration from loss of fluids. Immune compromised
persons are at risk for dehydration because they may get a more
serious illness, with greater vomiting or diarrhea. They may need
to be hospitalized for treatment to correct or prevent dehydration.
Is the illness
contagious? How are these viruses spread?
Yes, viral gastroenteritis is contagious. The viruses that cause
gastroenteritis are spread through close contact with infected persons
(for example, by sharing food, water, or eating utensils). Individuals
may also become infected by eating or drinking contaminated
foods or beverages.
How does food
get contaminated by gastroenteritis viruses?
Food may be contaminated by food preparers or handlers who have
viral gastroenteritis, especially if they do not wash their hands
regularly after using the bathroom. Shellfish may be contaminated
by sewage, and persons who eat raw or undercooked shellfish harvested
from contaminated waters may get diarrhea. Drinking water can also
be contaminated by sewage and be a source of spread of these viruses.
Where and when does viral
Viral gastroenteritis affects people in all parts of the world.
Each virus has its own seasonal activity. For example, in the United
States, rotavirus and astrovirus infections occur during the cooler
months of the year (October to April), whereas adenovirus infections occur throughout
the year. Viral gastroenteritis outbreaks can occur in institutional
settings, such as schools, child care facilities, and nursing homes,
and can occur in other group settings, such as banquet halls, cruise
ships, dormitories and campgrounds.
Who gets viral gastroenteritis?
Anyone can get it. Viral gastroenteritis occurs in people of all
ages and backgrounds. However, some viruses tend to cause diarrheal
disease primarily among people in specific age groups. Rotavirus
infection is the most common cause of diarrhea in infants and young
children under 5 years old. Adenoviruses and astroviruses cause
diarrhea mostly in young children, but older children and adults
can also be affected. Norwalk and Noroviruses are more likely to
cause diarrhea in older children and adults.
How is viral
Generally, viral gastroenteritis is diagnosed by a physician on
the basis of the symptoms and medical examination of the patient.
Rotavirus infection can be diagnosed by laboratory testing of a
stool specimen. Tests to detect other viruses that cause gastroenteritis
are not in routine use.
How is viral gastroenteritis
The most important of treating viral gastroenteritis in children
and adults is to prevent severe loss of fluids (dehydration). This
treatment should begin at home. Your physician may give you specific
instructions about what kinds of fluid to give. CDC recommends that
families with infants and young children keep a supply of oral rehydration
solution (ORS) at home at all times and use the solution when diarrhea
first occurs in the child. ORS is available at pharmacies without
a prescription. Follow the written directions on the ORS package,
and use clean or boiled water. Medications, including antibiotics
(which have no effect on viruses) and other treatments, should be
avoided unless specifically recommended by a physician.
Can viral gastroenteritis
Yes. Persons can reduce their chance of getting infected by frequent
handwashing, prompt disinfection of contaminated surfaces with household
chlorine bleach-based cleaners, and prompt washing of soiled articles
of clothing. If food or water is thought to be contaminated, it
should be avoided.
Is there a vaccine
for viral gastroenteritis?
There is no vaccine or medicine currently available that prevents
viral gastroenteritis. A vaccine is being developed, however, that
protects against severe diarrhea from rotavirus infection in infants
and young children.