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Gastroenteritis (cont.)

What Are the Signs and Symptoms the Stomach Flu (Gastroenteritis)?

By definition, gastroenteritis affects both the stomach and the intestines, resulting in vomiting and diarrhea.

Common stomach flu (gastroenteritis) symptoms and symptoms

  • Low grade fever, usually less than 100 F (37.7 C)
  • Nausea with or without vomiting
  • Mild-to-moderate diarrhea (Dehydration also can intensify the symptoms of nausea and vomiting.)
  • Crampy painful abdominal bloating (The cramps may come in cycles, increasing in severity until a loose bowel movement occurs and the pain re resolves somewhat leaving a dull ache.)

More serious signs and symptoms of stomach flu (gastroenteritis)

  • Blood in vomit or stool (this is never normal and the affected individual should seek immediate medical care)
  • Vomiting more than 48 hours
  • Fever higher than 101 F (40 C)
  • Swollen abdomen
  • Increasingly severe abdominal pain
  • Dehydration - weakness, lightheadedness, decreased urination, dry skin, dry mouth and lack of sweat and tears are characteristic symptoms of dehydration.
  • If symptoms continue or worsen, call a health-care professional.

Diarrhea is one of the leading causes of infant sickness and death. Worldwide, diarrhea accounts for 3-5 million deaths yearly for all age groups. In general, most adults and children recover after they are appropriately rehydrated.

What Causes the Stomach Flu (Gastroenteritis)?

Gastroenteritis has many causes. Viruses and bacteria are the most common.

Viruses (Norovirus, Rotavirus, Adenoviruses, Parvoviruses, and Astroviruses)

Norovirus - Fifty to seventy percent of cases of gastroenteritis in adults are caused by noroviruses (genus Norovirus, family Caliciviridae). This virus is highly contagious and spreads rapidly. Norovirus is the most common cause of gastroenteritis in the United States.

  • Noroviruses can be transmitted by
    • consuming contaminated food and liquids,
    • touching objects contaminated with Norovirus and then placing the hands or fingers in the mouth,
    • direct contact with an infected individual (for example, exposure to Norovirus when caring for or sharing foods, drinks, eating utensils with an affected individual, and
    • exposure to infected individuals and objects in daycare centers and nursing homes.
  • Norovirus is often in the news when cruise ship passengers contract the virus causing gastroenteritis epidemic on board the ship.

Rotavirus - According to the CDC, "Rotavirus was also the leading cause of severe diarrhea in U.S. infants and young children before rotavirus vaccine was introduced for 2006. Prior to that, almost all children in the United States were infected with rotavirus before their 5th birthday. Each year in the United States in the pre-vaccine period, rotavirus was responsible for more than 400,000 doctor visits; more than 200,000 emergency room visits; 55,000 to 70,000 hospitalizations; and 20 to 60 deaths in children younger than 5 years of age."

Other viruses that cause gastrointestinal symptoms include:

Adenoviruses - This virus most commonly causes respiratory illness; however, other illnesses may be caused by adenoviruses and include gastroenteritis, bladder infections, and skin rashes.

Parvoviruses - The human bocavirus (HBoV), which can cause gastroenteritis belongs to the family Parvoviridae.

Astroviruses - Astrovirus infection is the third most frequent cause of gastroenteritis in infants.

Parasites and Protozoans (Giardia, Cryptosporidium)

These tiny organisms are less frequently responsible for intestinal irritation. A person may become infected with one of these by drinking contaminated water. Swimming pools are common places to come in contact with these parasites. Common parasites include

  • Giardia is the most frequent cause of waterborne diarrhea, causing giardiasis. Often, people become infected after swallowing water that has been contaminated by animal feces (poop). This may occur by drinking infected water from river or lakes but giardia may also be found in swimming pools, wells and cisterns.
  • Cryptosporidium (Crypto) is a parasite that lives in the intestine of affected individuals or animals. The infected individual or animal sheds the Cryptosporidium parasite in the stool. Crypto may also be found in food, water, soil, or contaminated surfaces (swallowing contaminated water, beverages, uncooked food, unwashed fruits and vegetables) or on contaminated surfaces (touching contaminated bathroom fixtures, toys, diaper pails, changing tables, changing diapers, caring for an infected individual or handling an infected cow or calf). Those at risk for serious disease are individuals with weakened immune systems.
Medically Reviewed by a Doctor on 8/31/2017

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