What’s the Difference Between a Flu and a Stomach Flu

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.
Stomach flu vs. flu symptoms
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 12 to 48 hoursTrusted Source after exposure and can last up to 3 days.
Flu symptoms
The flu, or influenza, is a respiratory condition that primarily affects your lungs, throat, and nose. Common symptoms includeTrusted Source:
• 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 3 to 7 daysTrusted Source or sometimes longer.
What causes stomach flu vs. the flu?
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 most commonTrusted Source causes are:
• norovirus (the most common cause of stomach flu in people of all ages)
• rotavirus
• adenovirus
• astrovirus

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 severalTrusted Source strains of the flu, but the most common are the influenza A and influenza B viruses, which cause seasonal flu outbreaks.
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.