Gastroenteritis is an inflammation that affects the lining of the stomach or intestines. It is caused by an infection with virus, bacteria, or parasites, which is taken-in by contaminated food or water, or by touching someone who is infected.
Like most sicknesses, Gastroenteritis has a plethora of causes. The most common way a human can catch gastroenteritis would have to be through a virus. Gastroenteritis can be spread though many different types of viruses, but the two most common viruses are rotavirus and norovirus. Rotavirus is the virus that causes diarrhea in young children or even infants. Norovirus is a virus that causes a very serious stomach flu. Another way that someone can catch gastroenteritis would be through bacteria. Bacteria such as E. coli or even salmonella can cause the stomach flu. Bacteria like these and especially salmonella are caused by when a cook or chef under cooks poultry. So it is very important to be careful when cooking food in order not to catch gastroenteritis. Another cause of gastroenteritis would be the contamination of drinking water. Parasites such as giardia and cryptosporidium can be found in normal drinking water or in lakes or swimming pools. Overall, the three main ways gastroenteritis can be spread would be: contact with a person who has the sickness, contaminated food or water that is ingested, or unwashed hands after going to the bathroom or changing a diaper. Also, there are other not as common ways that someone can get gastroenteritis some of these would include: drinking water that contains heavy metals (arsenic, cadmium, lead, or mercury), intake of foods that have a high concentration of acid such as citris fruit or tomatoes, toxins that can be found in seafood, or even medications like antibiotics, antacids, laxatives, and chemotherapy drugs.
The normal flu, commonly referred to as influenza, affects the persons respiratory system. This would include the nose, throat and lungs of the person with influenza. However, gastroenteritis affects the intestines of the human. It causes symptoms that include: diarrhea (watery), cramps and pains in the abdominal muscles, vomiting and or nausea, a low grade fever, muscle aches or a head ache. Gastroenteritis symptoms will regularly occur one to three days after the person has come in contact or has been infected by gastroenteritis. Symptoms of gastroenteritis will usually only last one to two days, but sometimes the symptoms can last for around ten days.
One should consult a physician if you have not been able to keep fluids down for more than twenty-four hours, if you are vomiting blood or vomiting for more than two days, if you are feeling dehydrated, or if you have a fever of more than 104 degrees F. 
When talking about the treatment of gastroenteritis, one must first know that the symptoms will often die down within the first few days. This is because the human immune system can often take care of the infection on its own thanks to the way that God designed us. Most of the ways to treat gastroenteritis do not completely cure all symptoms, but they are used to ease the severity of the symptoms. One thing that is very important to do if someone has gastroenteritis is to make sure that they stay hydrated. So the intake of fluids is imperative for a patient that has gastroenteritis. if one is to have a watery stool (diarrhea), it is important to have at least 200ml of liquids after each bout of diarrhea. Also one must continually be drinking about two liters of liquids each day. Different types of fluids should include mainly water or soups, but one should stay away from liquids that contain a plethora of sugars, such as pop or juices because they have been known to make diarrhea worse. In regards for what you should eat, it used to be said that one should refrain from eating in order to not have diarrhea. But nowadays doctors recommend to have small, light normal meals if you are able to. One should avoid eating heavy fats in their food along with avoiding spicy food to avoid upsetting the stomach even more. In terms of medication that one can take for gastroenteritis, anti-diarrheal medications can be obtained from a local pharmacy. The most safe anti-diarrheal medication would be loperamide. Also ibuprofen is recommended to ease a high temperature or a bad headache. Also if a doctor recommends it, an antibiotic may be used to treat gastroenteritis. 
Everything you need to know about gastroenteritis
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