Stomach flu is the layman term for viral gastroenteritis, infection of the intestine. The source of the infection is often contaminated food or water. The condition is contagious and can be contracted by sharing contaminated utensils or touching contaminated surfaces.
According to the Centers for Disease Control and Prevention, norovirus is the most common cause of stomach flu, accounting for 19-21 million cases per year in the U.S. alone. Rotavirus infection is the other causative factor that results in stomach flu across the world.
Food poisoning is a foodborne illness with gastrointestinal symptoms similar to viral gastroenteritis. The causative factor of the condition can be viral, bacterial or parasites. Food poisoning can also be contagious.
According to the Centers for Disease Control and Prevention, there are 250 different foodborne illnesses, accounting for almost 48 million cases every year in the U.S.
Signs and symptoms
The signs and symptoms of viral gastroenteritis and food poisoning are quite similar. Both of the conditions resolve within few days. The signs and symptoms may progress to complications in high-risk cases, but they are hard to overlook due to their severity.
Stomach flu symptoms last from three to ten days depending upon the severity of the infection and presents as;
- Watery diarrhea without any blood
- Nausea or vomiting or both
- Pain in the abdomen with cramping
- Low-grade fever
- Rarely, muscle aches or headache
Children and infants with stomach flu may have a high-grade fever and are lethargic or irritable.
The signs and symptoms of food poisoning start within hours or rarely after some days or weeks of consuming contaminated food. The symptoms usually reside within hours or days, depending upon the severity of the infection.
- Watery diarrhea with or without blood
- Abdominal pain and cramps
Differences between stomach flu and food poisoning
The difference between the two conditions is in their;
- Causative factor
Stomach flu is a viral infection of the intestine, while food poisoning can be bacterial, viral or parasitic in origin.
The most common causes of stomach flu include norovirus, rotavirus and adenovirus.
Food poisoning is commonly caused by bacteria, namely salmonella and staphylococcus aureus.
- Spread and transmission
Both conditions are contagious with different modes of acquisition.
Stomach flu is contracted via the fecal-oral route and by touching or using contaminated surfaces as utensils etc.
Food poisoning is contracted via eating uncooked, raw food or by food contaminated with bacteria, virus or parasite.
- Signs and symptoms
Both conditions upset the bowel; however, diarrhea of stomach flu is not bloody, while food poisoning can be accompanied by blood.
Stomach flu is associated with weight loss, muscle aches and pain, joint pain, general malaise and headache. Fever without chills is present.
On the other hand, food poisoning is accompanied by fever with chills and shivers and severe abdominal pain, which often complicate shock and unconsciousness.
- Onset and course of signs and symptoms
Stomach flu begins within 72 hours of contracting the virus, lasts for few days and usually resolves within ten days.
The signs and symptoms of food poisoning can appear anytime, within hours to days to weeks. The condition resolves typically within two days.
Stomach flu is not fatal, provided adequate fluid and electrolyte management is administered.
On the contrary, a type of food poisoning called botulism is a fatal condition if not addressed adequately within time.
When to see a doctor
You need to see a doctor in case of the following symptoms;
- Signs of dehydration develop
- Consistent vomiting for more than two days
- Inability to keep liquid down
- Blood in feces
- High grade fever
Both the conditions are treated with;
- Adequate rest
- Managing fluids and electrolytes
- Soft diet
Besides all of the above, food poisoning is treated with fever-reducing medicines. The underlying causative factor is treated accordingly, for example, antibiotics in case of bacterial food poisoning.
Stomach flu is a viral infection, and antibiotics are of no use in such a case. However, a vaccine against the rotavirus is available for children that can help prevent viral gastroenteritis effectively. Adequate sanitary facilities and good personal hygiene practices can prevent the spread of stomach flu. Preparing (cleaning and cutting) and cooking food, and handling perishable items properly cuts back the risk of food poisoning. Of course, good hygienic practices are essential to prevent diseases in all cases.