First, a disclaimer. The stomach "flu" is not actually the flu or influenza. Influenza is a serious viral illness characterized by fever, chills, body aches and occasionally vomiting or diarrhea. There is a high rate of complications, including pneumonia. When people refer to an ailment as the stomach flu, they generally mean a self-limited viral illness called gastroenteritis. Therefore, this post is really what to do about gastroenteritis, but that doesn't rhyme.
What is gastroenteritis?
Gastroenteritis is a viral illness that causes vomiting, diarrhea and usually fever. Patients will frequently have a bad stomach ache as well. The illness can be caused by viruses, bacteria or parasites but for the purpose of this post we will focus on viral gastro (that’s what pediatricians call it for short) because that is the most common type we see. There are several viruses that will cause gastro including Rotavirus (more on this later), Norovirus (the cruise ship infection) and Adenovirus (a very unpleasant flu-like illness). They are spread through the fecal-oral route, which means dirty hands touch an object or food then the virus lives there until someone else touches it or ingests it. Several days after ingestion, the virus causes inflammation of the lining of the GI tract and subsequent vomiting and diarrhea.
What should you expect?
In my experience, most kids with gastro will have 24-48 hours of vomiting followed by 5-7 days of diarrhea. The illness goes away on its own without antibiotics. In fact, many bacterial causes of gastro do not require antibiotics and children with some types of bacterial gastro who get antibiotics can be at increased risk for kidney problems. The moral of the story is not to expect antibiotics for viral gastroenteritis. More on antibiotic use here.
The main complication of gastro is dehydration. Typical symptoms of dehydration include dry mouth, thirst, dizziness, cool finger tips, lack of tears and decreased urination. Most healthy children who are able to drink can easily avoid dehydration.
What can you do for your child?
There isn’t any specific treatment to make the virus go away faster, but there are many things you can do to help your child feel better. For stomach ache and/or fever, you can give your child Tylenol. I generally advise against Ibuprofen because of the potential risk of stomach irritation, as well as the risk to the kidneys in children under 1 if they are potentially dehydrated. For vomiting, the best thing to do is have your child rest his/her belly. One of the biggest mistakes that I see from parents is trying to feed their child too soon and then the child continues to vomit. Avoid food for the first 24 hours and give clear fluids in small volumes. For babies, use Pedialyte and give 1-2 teaspoons every 20 minutes. Continue doing that as long as the vomiting has subsided and gradually increase the volume as you go. For older kids you can give ice chips or popsicles, which slowly drip into the stomach allowing the child to rehydrate without causing further vomiting. If the vomiting seems to be under control, you can give soup or broth but continue to avoid solid foods until it has been a good 12-24 hours. While there is medication available to stop the vomiting, it is not without side effects and does not shorten the course of the illness. I usually only recommend it if a child is persistently vomiting without keeping in fluids and is at risk for dehydration. Stopping the vomiting does not make the virus go away any sooner.
For diarrhea, a return to solid foods as soon as your child is ready will help. Once your child is ready to eat, you can give him/her almost anything. The traditional BRAT diet (bananas, rice, applesauce toast) is no longer recommended. You can give those foods but any food with fiber, like fruits and vegetables, can firm up the stool. Yogurt with live active cultures is also helpful. Avoid sugary foods and beverages like juice and soda because they make the stool more watery and prolong diarrhea. If the diarrhea persists beyond 3-4 days, some children become temporarily lactose intolerant as the lactase enzyme is shed from the lining of the GI tract. Therefore, you may have to avoid dairy products until your child is completely better. As with vomiting, there is medication that can temporarily stop the diarrhea but it does not make the virus go away and therefore is not advised.
What is Rotavirus?
Rotavirus is a viral infection that typically causes severe gastroenteritis in infants. The volume of stool output can be so large that small infants are at high risk of dehydration and even death. Worldwide, diarrhea illnesses are responsible for around 500,000 deaths per year. In the past, Rotavirus infection typically led to lots of hospitalizations (up to 70,000 per year). Those of us who were in training pre-vaccine can probably remember the smell of a ward filled with babies infected with Rotavirus during the winter. Since the introduction of the Rotavirus vaccine, there has been a reduction of hospitalizations due to Rotavirus by over 85%.
What else should I watch for?
As previously stated, bacteria and parasites can also cause diarrhea. If you see blood in the diarrhea or the diarrhea is lasting more than 7 days, see your pediatrician for possible tests. This is especially true if you have traveled out of the country, drink well water, have a pet or have been camping recently and drank from a stream. Furthermore, severe pain in the right lower part of the abdomen can be a sign of appendicitis so seek medical care immediately if you suspect that is the case.