Healthy Living

What Are the Causes of Viral Diarrhea?

What Are the Causes of Viral Diarrhea?

Diarrhea is a condition characterized by three or more loose bowel movements. Loose bowels are said so as the nature of the motions are liquid (or semi-solid) due to the body’s inability to absorb fluid from the stool. Commonly, this disorder may lead to dehydration after lasting for a couple of days. With increasing severity of this condition the patient might show the following symptoms:

  • Rapid heart rate
  • Infrequent urination
  • Becoming less responsive and exhausted
  • Skin loses color and turns pale
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Diarrhea may be due to the presence of one or more viruses in a food. It attacks the digestive system and causes painful burning feeling in the stomach and intestines. Other than a virus, a bacteria or parasite may even cause diarrhea (Gastroenteritis).

When diarrhea occurs due to a virus, it is named ‘stomach flu' (not by any way related to Influenza). It is a highly infectious disease and easily gets transmitted from one body to another. There are three main kinds of this condition:

  • Persistent diarrhea (if it lasts more than two weeks)
  • Short duration watery diarrhea (rare and can be caused by cholera)
  • Short duration bloody diarrhea (Dysentery or blood in the stools)

In addition to the above causes, there may be some underlying disease causing diarrhea, such as


There are several types of virus that are responsible for stomach flu. The infection is spread through contaminated food and water.

The most common viruseswhich cause this are listed below-


Rotavirus is the most common cause of diarrhea amongst infants and youngsters. Infants aging from 3 to 15 months are an easy target for this virus for causing infection. Diarrheal symptoms do not always show up right from the day an individual is infected. They get exposed slowly and usually it takes 1-3 days to reveal all the effects of viral diarrhea. The most typical signs of rotavirus contamination are frequent vomiting and loose stool for as many as 3-5 times a day. It causes fever and uncomfortable abdominal pain. The symptoms are more clearly seen in children than adults. 

Out of the eight species of this virus (A – H), the Rotavirus A is the predominant one. No amount of drugs and antibiotics are helpful in treating this infection. Globally approved vaccinations are the only way to go.


Adenovirus mostly affects infants and children below 2 years of age. There are 49 types of this virus and only one of them can cause diarrhea. The signs of virus attack do not appear on the day of attack just like rotavirus. It takes 8 to 10 days for them symptoms to get exposed. Diarrhea caused by adrenovirus does not recover quickly lasting 5 to 12 days at least.


Calicivirus attacks people regardless of their age. Among the calicivirus family, norovirus(or Norwalk virus) is the most common pathogen that causes diarrhea, especially in adults. It can cause diarrhea in an epidemic form and it attacks more frequently during the months of October to April. When someone gets infected with norovirus, they show symptoms like nausea, cramping, abdominal pain, severe diarrhea etc. The signs of norovirus attack expose 1 to 2 days later and stays for 1 to 3 days.  

Norovirus is the leading cause of the diarrheal epidemic (non-bacterial) around the world. It is also responsible for most of the outbreaks caused by food-borne vectors since it spreads through the food first infected by the affected.  


Astrovirus attacks both children and adults and causes diarrhea. Nausea is also a common problem when a human body is contaminated with this virus. The symptoms are visible after 3-4 days of attack and takes 2-7 days to recover. Though contamination by astrovirus occurs throughout the whole year, the virus is mostly active in the winter season.  


A patient needs to go through a physical examination before the actual diagnosis. The physical exam will determine if there is any presence of viruses that is spreading through his body. Doctors will ask for a stool sample to find out the pathogen responsible for the patient's disease.


As diarrhea causes dehydration, the main goal of the treatment will be to ensure that the patient's body maintains an adequate level of hydration. If the case is serious, the patient is admitted to a hospital and given the required fluids so that there is enough presence of a liquid to keep a proper hydration level in his body.

OHS (Oral rehydration solutions) works great especially on children's stomach as it contains a good ratio of water and salt. It hydrates the body quickly and helps restock the necessary fluids. OHS is basically a solution that is easily found at every local pharmacy.

It should be noted that antibiotics do not have any effect on viruses. There are some self-care steps that work as a great way to get relieved of this disease. The patient should:

  • Ensure extra intake of water.
  • Avoid fruit juice as they sometimes lead to an increase in diarrhea.
  • Drink sports drinks as they are a great source of electrolytes.
  • Take proper rest as the body becomes very week during these days.
  • Do not take any kind of medicine without consulting the doctor.
  • Do not take aspirin while suffering from diarrhea caused by a virus because it can lead to Reye's syndrome, which can easily be life-threatening. 

The Bottom Line

The viruses causing diarrhea, directly attack the gut and cause several uncomfortable feelings. Both infants and adults suffer from this disease, which sometimes can go severe if attacked by dangerous viruses. For the newborn, breast milk is immensely helpful in preventing such an infection. People must stay away from dirty places and foods to maintain a healthy and disease-free life. 

Sanitation and proper hygiene should be made a habit of every day. Only with a nutritious diet and clean drinking water can this epidemic be evaded correctly.