Although flu and stomach flu sound similar, they are caused by different viruses and have different symptoms and treatment.
People sometimes confuse flu and stomach flu because of their similar names. But these conditions result from different viruses and affect your body in different ways. The flu affects your respiratory (breathing) system, while the stomach flu primarily affects your digestive system.
In this article, we’ll explore how flu (influenza) and stomach flu (viral gastroenteritis) differ. You’ll learn about their symptoms, causes, and treatment options and how to prevent them. We’ll also answer some frequently asked questions to help you better understand these conditions.
Both the flu and the stomach flu can make you feel unwell, but they have different symptoms.
Stomach flu symptoms
Stomach flu, also known as viral gastroenteritis, primarily affects your digestive system. Symptoms typically include:
- nausea with or without vomiting
- diarrhea
- stomach cramps
- mild fever (usually under 101°F or 38°C)
- fatigue and weakness
- headache
Symptoms of stomach flu usually appear
Flu symptoms
The flu, or influenza, is a respiratory condition that primarily affects your lungs, throat, and nose. Common symptoms
- fever (often over 101°F or 38°C)
- chills and sweats
- dry cough
- sore throat and runny nose
- muscle aches and body pain
- fatigue and weakness
- headache
Flu symptoms tend to come on suddenly and can last for
Although both the flu and the stomach flu are viral infections, the viruses that cause each one are different.
Stomach flu causes and risk factors
Stomach flu results from viruses that infect your digestive system. The
Stomach flu is highly contagious and spreads through contact with contaminated food, water, or surfaces. Risk factors include being in close contact with someone who has the virus and being in crowded places such as schools or nursing homes. Babies and children have a higher risk of contracting rotavirus, adenovirus, and astrovirus.
Flu causes and risk factors
The flu is caused by the influenza virus. There are
The flu spreads mainly through respiratory droplets when a person who has the virus coughs, sneezes, or talks. You can also get the flu by touching contaminated surfaces and then touching your mouth, nose, or eyes.
The following groups of people are at risk of developing serious complications from both types of flu:
- people 65 years old and older
- children younger than 5 years old
- pregnant people
- people with medical conditions such as:
- lung, kidney, liver, and heart diseases
- diabetes and other metabolic disorders
- obesity
- severe anemia
- a compromised immune system
In most cases, you can manage either condition at home with rest and hydration. But you should contact a doctor if you or someone you’re with experiences any of the
- severe dehydration (dry mouth, dizziness, dark urine)
- a fever above 102°F (39°C) that does not improve with medication
- blood in vomit or stool
- difficulty breathing or chest pain
- seizures
- symptoms that last longer than 1 week
Diagnosing the flu usually involves a physical exam and a rapid flu test. Doctors may use a nasal or throat swab to check for the influenza virus. Results can be available within minutes to hours.
Stomach flu, on the other hand, is typically diagnosed based on your symptoms, especially if you have diarrhea and vomiting. Lab tests may sometimes be necessary if you’re experiencing severe dehydration or if your doctor suspects a bacterial or parasitic infection.
There is no cure for either condition, but treatment can help relieve your symptoms and help prevent dangerous complications such as dehydration.
Stomach flu treatment
Rest, hydration, and some over-the-counter drugs (such as Imodium for diarrhea) may help treat symptoms.
Flu treatment
Rest, hydration, and fever reducers such as ibuprofen and acetaminophen can help treat flu symptoms. Certain prescription drugs, including Tamiflu, may also be beneficial.
Prevention strategies for both flu and stomach flu focus on good hygiene and vaccination:
- Washing your hands: Wash your hands frequently with soap and water, especially before eating or after using the restroom.
- Getting vaccinated for the flu: Getting the flu vaccine every year is one of the most
effective ways to prevent influenza. - Getting vaccinated for rotavirus: Babies
should receive the rotavirus vaccine to prevent serious complications of stomach flu. - Avoiding contact with people who are sick: Try to limit your contact with people who are sick, and avoid sharing food, drinks, or utensils.
How do I know if it’s a stomach flu?
If your symptoms mainly include nausea, vomiting, diarrhea, and stomach cramps, you likely have a stomach flu. The symptoms usually resolve within a few days to a week.
What can be mistaken for stomach flu?
Food poisoning and infections such as salmonella can cause symptoms similar to those of stomach flu. But food poisoning can have more severe symptoms and usually resolves more quickly.
Read more about the differences between food poisoning and stomach flu.
How contagious is stomach flu?
Stomach flu is highly contagious, especially in crowded places such as schools and nursing homes. The virus can be contagious for several days, even after symptoms subside.
How long does stomach flu last?
Stomach flu typically lasts
What kills a stomach virus?
Washing your hands frequently and disinfecting surfaces with bleach or alcohol-based cleaners can help eliminate viruses that cause stomach flu.
The flu and the stomach flu are viral infections that cause different symptoms and affect different parts of your body. The flu is a respiratory condition that causes symptoms such as fever, body aches, and cough, while stomach flu affects your digestive system, causing nausea, vomiting, and diarrhea.
Understanding the differences between these conditions can help you better manage your symptoms and reduce transmission of these viruses. If your symptoms become worse or don’t go away, it’s always a good idea to seek medical advice.