Medically known as gastroenteritis, stomach flu is an infection marked by inflammation of the large and small intestines as well as the stomach and varied symptoms like stomach cramping and uneasiness, vomiting, nausea, and diarrhea. Globally, it is one of the major causes of fatalities in children younger than 5 years old. The lack of appropriate treatment for stomach flu causes the death of about 5 to 8 million per year.

Stomach flu is not related to influenza. The duration of stomach virus infection is dependent on varied factors, including the general health and age of the person as well as the severity of the associated symptoms. In most cases, the symptoms disappear within 7 days, but may occasionally persist for 3 to 4 weeks.

Depending on the type of virus that is causing the infection, stomach flu can remain contagious from some days to 2 weeks or more. The condition can occur due to numerous types of viruses such as rotavirus, norovirus, etc. Each of these viruses come with a different duration for which gastroenteritis remains contagious.

Stomach virus infection may not be a serious ailment, but it should be ignored. Patients need to seek immediate medical attention as well as drink lots of water and fluids.

Symptoms of stomach flu

Some of the common signs and symptoms of a stomach virus infection/stomach flu are listed below:

• Diarrhea, loose watery stools that occur frequently
• Abdominal cramping
• Pain in stomach
• Vomiting, which may lead to dehydration
• Muscle aches
• Headache
• The presence of bloody diarrhea accompanied by fever is an indication of bacterial stomach flu.

Patients will typically elicit the symptoms a day or 2 after getting infected by the culprit stomach virus. The severity of the viral infection plays a major role in determining the duration of gastroenteritis. The elderly, young children, and infants with stomach flu often tend to experience worsening of the condition due to dehydration and insufficient intake of fluids to compensate for such loss of fluids from the body. Such individuals may suffer from stomach virus for 3 weeks or even more.

Recurrent and persistent diarrhea can cause dehydration; this can result in symptoms like rapid heartbeat, fatigue, sunken eyes, and reduced urination.

Causes of stomach flu

Viral stomach flu is more prevalent as opposed to bacterial gastroenteritis. Stomach virus infection can occur due to varied viruses such as rotaviruses, noroviruses, sapoviruses, adenoviruses, caliciviruses, and astroviruses.

• Rotavirus is the main cause of stomach flu in young children and infants. The stomach virus is contagious even before the development of symptoms which occur 1 to 2 days after contact with the virus. It remains contagious for nearly 2 weeks post recovery.
• Norovirus is the main cause of stomach flu in children and adults. The stomach virus is contagious from the time patients start to feel sick and symptoms occur 1 to 2 days post exposure. Recovery occurs in a day or two, but the virus continues to be contagious for nearly 3 days post recovery. In some patients, the stomach virus may stay contagious for nearly 2 weeks post recovery.

Other pathogens that can cause stomach flu include parasites like Cryptosporidiumand Giardia, and bacteria like E. coli, Salmonella, Shigella, or Campylobacter.

• Giardia infection may occur due to drinking well water or swimming in contaminated lake/pool water.

Stomach virus is very contagious and tends to spread in the following ways:

• Direct contact with a patient
• Intake of contaminated drinks and/or foods
• Sharing water, food, eating utensils, and/or other personal items with an infected individual.
• Contamination of food due to unhygienic habits of people handling or preparing it.
• Contact with contaminated objects or surfaces
• Eating undercooked or raw shellfish harvested in contaminated waters
• Eating uncooked seafood that is contaminated with sewage
• Stomach flu outbreak can occur due to drinking water adulterated with sewage
• Use of untreated water for brushing or drinking when travelling, which allows the virus to enter the body

Treatment of stomach flu

Treatment of gastroenteritis is dependent on diagnosis of the virus that is causing the condition. Doctors will then prescribe varied medications, etc. to treat the illness and infection.

• Dehydration is one of the major symptoms of stomach flu. Hence, before medical treatment begins, patients are usually given ORS or oral rehydration solution to replace the lost electrolytes and fluids. Patients with severe dehydration who cannot drink fluids due to nausea may be given intravenous administration of fluids.
• Rotavirus vaccines are currently available to prevent stomach rotavirus infection in infants.

Following the below listed guidelines can help prevent stomach flu:

• Daily washing of bed sheets, clothes, napkins, and towels, etc., used by patients.
• Practicing personal hygiene such as use of clean utensils for eating and cooking, frequently washing hands, etc.
• Intake of food that is prepared hygienically and drinking clean water
• Abstaining from consumption of raw foods, untreated water, and unpasteurized milk. Also avoid ‘iffy’ non-reliable beverages and foods.