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Stomach bugs are a leading cause of sickness and diarrhea in adults and children, especially in the winter months.
In this article, we look at the symptoms, causes, and treatment of 24-hour stomach bugs, including tips to avoid transmitting them to other people.
Viruses that spread from person to person are responsible for 24-hour stomach bugs. People sometimes call this illness “stomach flu,” but it is not related to the seasonal influenza that causes a respiratory illness every fall and winter. The medical name for the stomach bug is acute viral gastroenteritis.
People often ask what the difference is between food poisoning and a stomach bug. Although a person can get sick with a viral stomach bug due to contaminated food or water, the term “food poisoning” commonly refers to foodborne illnesses resulting from bacteria, parasites, or toxins that these organisms release when food goes bad.
Food poisoning essentially just describes how the germ got into the body, but all of the germs that cause food poisoning can also spread through poor hygiene and touching contaminated surfaces.
The symptoms of a stomach bug can include:
People usually develop symptoms 12–48 hours after exposure to the virus.
Many people only experience these symptoms for 24 hours, but it is not uncommon for 24-hour stomach bugs to last longer than 1 day. In adults, a case of viral gastroenteritis typically lasts 1–3 days. In children, stomach bugs can last up to 12 days, depending on the cause.
Stomach bugs occur due to viruses. Common examples include:
Norovirus is the leading cause of vomiting and diarrhea from acute viral gastroenteritis among people of all ages in the United States, according to the Centers for Disease Control and Prevention (CDC). Rotavirus and adenovirus mainly affect children under the age of 2 years.
Most norovirus outbreaks in the U.S. happen between November and April. Sometimes, a new strain of norovirus develops. In the years where this happens, cases can increase by 50%.
Many people lose their appetite when they have a stomach bug, and they may find it difficult to keep liquids down. Sipping them slowly can help people stay hydrated. People can try:
- fruit juices
- sports drinks
Bland, salty foods, such as crackers, can help replace electrolytes. People can also drink rehydration solutions that contain electrolytes. Examples include:
A doctor may prescribe medication to control severe vomiting. However, they will not prescribe antibiotics because these drugs do not work for viral illnesses, including 24-hour stomach bugs.
In some cases, adults can take over-the-counter (OTC) medicines to treat diarrhea. These include loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol or Kaopectate).
However, if a person has bloody diarrhea or a fever, they should avoid these medications and seek help from a doctor right away.
Not all OTC medications are suitable for young children. People should consult a doctor before giving diarrhea medications to others.
Although most people with a stomach bug recover in a few days, some people may need medical help. These people include those who are in severe pain, are pregnant, or show signs of dehydration.
If someone is vomiting and has diarrhea multiple times a day, they can become dehydrated. It is especially important to watch out for this in children, older adults, and people with preexisting health conditions.
The symptoms of dehydration include:
- extreme thirst
- a decrease in urination
- dark coloured urine
- a dry mouth and throat
- feeling dizzy, lightheaded, or faint
- feeling tired
- sunken eyes or cheeks
- skin not flattening back to normal right away after pinching it
Anyone who thinks that they or someone else might be dehydrated should seek medical attention immediately. Doctors may advise a person with severe dehydration to go to the hospital for treatment.
Children and infants
For children, newborns, and infants, stomach bugs can become dangerous. A person should call a doctor if a child has symptoms of a stomach bug.
There are some additional signs of dehydration to look for in young children, including:
- crying with few or no tears
- urinating less, or no wet diapers for 3 hours or more
- unusually sleepy or fussy
Untreated dehydration can be fatal in children, so it is important to treat dehydration as an emergency.
Other symptoms that need medical attention
A person should see a doctor if they or someone in their care has the following symptoms:
- confusion or a change in their mental state
- diarrhea lasting more than 2 days
- severe pain in the abdomen or rectum
- very frequent vomiting
- stools that are black and tarry or contain blood or pus
- an inability to drink fluids without vomiting
The viruses that cause stomach bugs are highly contagious, and it is easy for someone to pass on the infection. The virus spreads through contact with small particles of the vomit or feces of a person with the infection. Someone can become infected if they:
- consume food or drink that the virus has contaminated
- touch contaminated surfaces and do not wash their hands
- have direct contact with someone who has the infection, for instance, when caring for them or eating with them
People are most contagious when they have active symptoms, such as vomiting, and for the first few days after they recover. However, 2 weeks after a person recovers from norovirus, the virus will remain in their stool.
People can help prevent the transmission of the virus by regularly and thoroughly washing their hands using soap and water. They should pay particular attention to washing the hands:
- after using the toilet
- after changing diapers
- after caring for someone who has a stomach bug
- after cleaning up after someone
- before giving medicine
- before eating, preparing, or handling food
People can use alcohol-based sanitizers to clean the hands, but using soap and water for 20 seconds is the most effective way to remove virus particles.
Here are some ways in which people can avoid transmitting a stomach bug:
- Someone who has or has recently had a stomach bug should not prepare food for anyone else for at least 2 days after their symptoms go away.
- People who work in restaurants, care facilities, schools, and other crowded places should avoid work for at least 2 days after their symptoms resolve.
- People should immediately clean and disinfect areas where someone has vomited or had diarrhea.
- A person should wear rubber gloves to remove soiled laundry items and wash them with detergent and hot water in the washing machine for the maximum cycle length.
- If possible, a person should dry laundry in a machine on the highest heat setting.
- When cleaning an infected area, a person should use rubber gloves and bleach-based cleaners and disinfectants. Leaving bleach-based cleaners on an affected area for 5 minutes helps kill the germs.
People can make a bleach solution with 5–25 tablespoons of household bleach per gallon of water. It is important to handle bleach with caution and care and to avoid ingesting it or touching it with bare skin.
A 24-hour stomach bug is a viral infection that passes from person to person. It causes symptoms such as vomiting and diarrhea, which usually last 1–3 days in adults.
Washing the hands thoroughly with soap and water, cleaning surfaces with bleach disinfectants, and washing contaminated laundry immediately can help prevent the transmission of stomach bugs.
If a person has a stomach bug, they must maintain their fluid intake to ensure that they do not become dehydrated. If someone has symptoms of dehydration, they should seek medical attention immediately.