Viral gastroenteritis

Acute infectious gastroenteritis is a common illness seen around the world. Viral pathogens cause most of these cases. Acute diarrheal disease is generally self-limiting in industrialized nations but can have significant morbidity for young and elderly patients. In underdeveloped countries, viral diarrheal diseases are a significant cause of death, especially in infants.[1][2] According to the Centers for Disease Control, viral gastroenteritis infections can account for over 200,000 deaths of children per year worldwide. Viral gastroenteritis is a known cause of nausea, vomiting, diarrhea, anorexia, weight loss, and dehydration. Isolated cases can occur, but viral gastroenteritis more commonly occurs in outbreaks within close communities such as daycare centers, nursing facilities, and cruise ships. Many different viruses can lead to symptomatology, though in routine clinical practice the true causative virus is generally not identified. Regardless of the viral cause, treatment is generally uniform and directed toward symptomatic improvement with a focus on hydration status. In the United States and other industrialized countries, the disease is most often self-limited and resolves in 1 to 3 days. However, in susceptible patients including young children, elderly patients, and the immunocompromised, hospitalization can occur without proper supportive care leading to increased morbidity and mortality.

Symptoms of gastroenteritis usually begin shortly after infection. For example, symptoms caused by norovirus typically develop within 12 to 48 hoursTrusted Source. Symptoms from adenoviruses may be delayed 3 to 10 days after contact.

Depending on which type of virus you’ve contracted, symptoms can last anywhere from 1 to 14 daysTrusted Source. Symptoms often start suddenly over the course of 1 or 2 hoursTrusted Source.

Symptoms can include:

loose, watery diarrhea more than 3 times per day

fever or chills

nausea and vomiting

headache, muscle aches, or joint aches

sweating or clammy skin

abdominal cramps and pain

loss of appetite

Diarrhea caused by viral gastroenteritis isn’t usually bloody. Blood in your stool could be a sign of a more severe infection.

You should seek emergency medical treatment if:

diarrhea has lasted for 2 days or more without getting less frequent

your infant develops diarrhea

blood is present in your diarrhea

you show or see signs of dehydration, such as dry lips or dizziness

Viral gastroenteritis is caused by a number of different viruses. It’s easy for these viruses to spread in group situations. Some of the ways the virus is transmitted include:

eating contaminated food or drinking contaminated water

being in close contact with someone who has the virus

sharing utensils or other items with someone who has the virus

touching contaminated surfaces

not washing hands properly, especially food handlers

Viral gastroenteritis affects people of all ages all over the world. But some factors can increase the risk of contracting viral gastroenteritis. People who are at a higher risk include:

children under the age of 5

older adults, especially those who live in nursing homes or assisted living facilities

people with a compromised or weakened immune system

those who are often in group settings, such as schools, dormitories, day care, religious gatherings, and other indoor group settings

Other factors that may increase the risk of becoming ill with viral gastroenteritis include:

being malnourished, especially low levels of vitamin A or zincTrusted Source

recent travel to developing countries

antibiotic or antacid use

anal intercourse

Several different types of viruses can cause viral gastroenteritis. The most common include:

norovirus

rotavirus

adenovirus

astrovirus

Let’s look at each of these viruses in more detail.

Norovirus

Norovirus is highly contagious and can affect anyone at any age. It spreads through contaminated food, water, and surfaces, or by people who have the virus. Norovirus is common in crowded spaces.

Norovirus is the leading causeTrusted Source of gastroenteritis in the United States and worldwide. Most outbreaks in the United States occur between November and AprilTrusted Source.

Symptoms include:

nausea

diarrhea

fever

body aches

According to the Centers for Disease Control and Prevention (CDC)Trusted Source, most people who become ill with norovirus start to feel better within 1 to 3 days of symptom onset.

Rotavirus

Rotavirus commonly affects infants and young children. Those who contract it can then pass the virus to other children and adults. It’s usually contracted and transmitted via the mouth.

Symptoms typically appear within 2 daysTrusted Source of infection and include:

vomiting

loss of appetite

watery diarrhea that lasts anywhere from 3 to 8 days

A rotavirus vaccine was approved for infants in 2006. Early vaccination is recommended to prevent severe rotavirus illnesses in infants and small children.

Adenovirus

The adenovirus affects people of all ages. It can cause several types of illness, including gastroenteritis. The adenovirus can also cause common cold-like symptoms, bronchitis, pneumonia, and pink eye (conjunctivitis).

Children in daycare, especially those under 2 years of ageTrusted Source, are more likely to get adenovirus.

Adenovirus is passed through the air via sneezing and coughing, by touching contaminated objects, or by touching the hands of someone with the virus.

Symptoms associated with adenovirus include:

sore throat

pink eye

fever

coughing

runny nose

Most children will feel better within a few days of experiencing adenovirus symptoms. However, symptoms such as pink eye may last longer than a few days.

Astrovirus

Astrovirus is another virus that commonly causes gastroenteritis in children. Symptoms associated with astrovirus include:

diarrhea

headache

mild dehydration

stomach pain

Gastroenteritis occurs all over the world and can affect people of all ages.

People who may be more susceptible to gastroenteritis include:

Young children. Children in child care centers or elementary schools may be especially vulnerable because it takes time for a child's immune system to mature.

Older adults. Adult immune systems tend to become less efficient later in life. Older adults in nursing homes are vulnerable because their immune systems weaken. They also live in close contact with others who may pass along germs.

Schoolchildren or dormitory residents. Anywhere that groups of people come together in close quarters can be an environment for an intestinal infection to get passed.

Anyone with a weakened immune system. If your resistance to infection is low — for instance, if your immune system is compromised by HIV/AIDS, chemotherapy or another medical condition — you may be especially at risk.

Gastroenteritis occurs all over the world and can affect people of all ages.

People who may be more susceptible to gastroenteritis include:

Young children. Children in child care centers or elementary schools may be especially vulnerable because it takes time for a child's immune system to mature.

Older adults. Adult immune systems tend to become less efficient later in life. Older adults in nursing homes are vulnerable because their immune systems weaken. They also live in close contact with others who may pass along germs.

Schoolchildren or dormitory residents. Anywhere that groups of people come together in close quarters can be an environment for an intestinal infection to get passed.

Anyone with a weakened immune system. If your resistance to infection is low — for instance, if your immune system is compromised by HIV/AIDS, chemotherapy or another medical condition — you may be especially at risk.

Wash your hands often, especially after using the bathroom and before food preparation. If necessary, use hand sanitizer until you can access soap and water.

Don’t share kitchen utensils, plates, or towels if someone in your household is sick.

Don’t eat raw or undercooked foods.

Wash fruits and vegetables thoroughly.

Take special precautions to avoid contaminated water and food when traveling. Avoid ice cubes and use bottled water whenever possible.

Ask your doctor if you should have your infant vaccinated against rotavirus. There are two vaccines, and they’re generally started around 2 months old.