Gastroenteritis is an infection of the guts (intestines). The severity can range from a mild tummy upset for a day or two with some mild diarrhoea, to severe diarrhoea and vomiting for several days or longer. Many viruses, bacteria, and other microbes (germs) can cause gastroenteritis.

Gastroenteritis

Causes

Gastroenteritis is caused by an infection of the stomach and intestine. The infection interferes with one of the main functions of the intestines the absorption of water and its distribution around the body.

This is why the most common symptoms of gastroenteritis are diarrhoea and vomiting; both of which are caused by the excess of unabsorbed fluids in the intestine.

It also explains why dehydration is such a common complication in gastroenteritis.

Certain intestinal parasites, particularly Giardia lamblia, stick to or invade the lining of the intestine and cause nausea, vomiting, diarrhea, and a general sick feeling. The resulting infection, called giardiasis, is more common in cold climates but occurs in every region of the United States and throughout the world. If the disease becomes persistent (chronic), it can keep the body from absorbing nutrients, a condition known as a malabsorption syndrome.

This intestinal condition is usually due to a viral or bacterial infection which inflames the lining of the stomach and intestines. The infection may be acquired from contaminated food or water, or it may be spread among people who are in close contact, particularly if personal hygiene is poor. Viral gastroenteritis is often caused by rotaviruses or astroviruses, especially in young children, and by the Norwalk virus in older children and adults. Most people acquire immunity to these viruses by the time they are adults. Bacterial causes of gastroenteritis include salmonella and E.scherichia Coli.

Between January 1996 and November 2000, 348 outbreaks of norovirus were reported to the CDC. Out of these, 54% patients were contaminated by food, 17% by person to person, 4% by water, and 25% by unidentified sources. Most of the food sources responsible were identified as oysters, salads, salad dressing, sandwiches, deli meats, cake and frosting, raspberries, drinking water, and ice. Shellfish have been implicated in some outbreaks, but it is not a frequent source on cruise ships, where the predominant mode of infection is believed to be fecal-oral and person to person from individuals who come onto the ships ill and do not report the illness or quarantine themselves in their cabins. Symptoms of Gastroenteritis

The main symptoms of viral gastroenteritis are watery diarrhea and vomiting. Other symptoms of gastroenteritis include headache, fever, chills, and abdominal pain. The symptoms may appear within hours or a few days of infection. They usually last for 1 to 2 days, but may last as long as 10 days.

Gastroenteritis can develop in one of two ways- through a viral infection or through a bacterial infection. However, both types of gastroenteritis share the same symptoms. The most common symptoms of this condition include nausea, vomiting, diarrhoea, loss of appetite, headache, abdominal pain, abdominal cramping, bloating, muscle aches, fatigue, weakness, chills, and a low-grade fever. These symptoms are not serious, and in the case of viral gastroenteritis, will usually run their course and subside in a few days. If treatment is necessary over-the-counter medications such as acetaminophen can be taken to relieve the majority of symptoms.

The symptoms of acute viral gastroenteritis include diarrhea, nausea and vomiting and loss of appetite. There usually is mild fever, generalized abdominal discomfort and cramps. Headaches and muscle cramps can also occur. Bacterial causes of infectious gastroenteritis are self-limited. They can occur from contamination of things we eat, or can be transmitted from contaminated areas. Food poisoning can produce symptoms very similar to acute infectious gastroenteritis. There is sometimes a relationship to those that ate the same food. They symptoms usually pass quite quickly.