To understand the most effective means of preventing stomach flu, it helps to know what causes stomach flu and how the disease spreads.

The stomach flu, which health professionals call viral gastroenteritis, is actually caused by a virus, so it’s not really a type of influenza. However, the term stomach flu has become commonplace over the decades and is now part of the parlance.

Viral gastroenteritis begins when one of several viruses enters the digestive tract, usually through the mouth. Stomach viruses are easily airborne and can float on air currents for surprising distances. If there is someone in your home who has symptoms of gastroenteritis, it is very likely that the viruses are circulating and landing on countertops, sinks, bathtubs, and other areas that are frequently touched by humans. Keeping food surfaces clean and disinfected in your home is essential for the prevention of stomach flu.

Gastroenteritis can also be spread directly from person to person. You can get the virus by touching, kissing, or shaking hands with an infected person, even if you haven’t gotten sick yet.

Eating food that has been touched by someone who has the virus is another way to get viral gastroenteritis. This is one of the reasons why many municipal health inspectors insist that restaurant employees wash their hands frequently. But at home, you should also make sure you don’t share eating utensils, cups, or napkins with someone who is infected. Clothing worn by infected people should be washed as soon as possible.

Certain foods may be contaminated before you buy them. Shellfish that come from sewage-polluted waters are one example. Dirty drinking water is another source of the virus.

Frequent and diligent handwashing is the best means of preventing viral gastroenteritis. The idea is to get the virus off your hands before you touch your mouth, which is something most people do unconsciously many times a day. Handwashing is particularly important before a meal, or after using the bathroom or changing a diaper. Hold your hands under running water for at least 20 seconds and use plenty of soap.

Alcohol-based hand gels have become popular in recent years and provide protection against some types of stomach viruses, but not all. They should not be considered a reliable method of preventing stomach flu.

Anyone with symptoms of gastroenteritis should stay away from the kitchen and should definitely not cook for others. If you normally cook meals for anyone, you should wait at least three days after symptoms are gone before you start cooking again. This is not always practical, of course. But if someone else can cook, or you can get takeout from restaurants for a few days, you’ll reduce the risk of someone else in the family getting sick.

Stomach flu prevention is hard work. You need to spend much more time than usual disinfecting floors, sinks, countertops, and other areas of your home or work space. There are some commercial disinfectants that are good at neutralizing the main types of stomach viruses, and you should read the labels carefully when using them. If you prefer a homemade disinfectant, mix a little bleach with water using 1 part bleach to 50 parts water. If you live in an area where water quality is questionable, use 1 part bleach to 10 parts cleaning water (obviously not drinking water).

At the moment, two types of vaccines have been approved that are formulated for the prevention of stomach flu, but they only work against one type of virus. They protect against severe diarrhea due to infection in infants and very young children. These vaccines are routinely given to children before their first birthday along with other childhood immunizations.

Researchers have recently made discoveries that may lead to an effective vaccine against other stomach viruses, but as of the publication of this article, none had been fully developed.