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Bug or food poisoning? What’s causing your upset stomach?

The painful reality is, we all know the feeling of an upset stomach. But when nausea and diarrhea hit, it isn’t always easy to tell if it’s because of something you have or something you ate.

Stomach bugs and food poisoning share many of the same unpleasant and unwelcome symptoms. Knowing the cause of your upset stomach can help you make the best plan of action when symptoms strike.


What causes a stomach bug?

When gut gunk is going around, we often refer to it to as the “stomach flu.” But the flu has nothing to do with your tummy.

Influenza is a respiratory illness that causes fever, chills, coughing, shortness of breath and other upper respiratory symptoms. Viral gastroenteritis is an inflammation of the stomach and intestines that’s caused by other viruses, bacteria or parasites.

The most common culprit is the highly contagious norovirus, which is responsible for up to 21 million cases of stomach bug in the U.S. each year. Most cases of stomach infection (also appropriately referred to as “winter vomiting disease”) occur between October and April, although you can contract norovirus year-round.


How do you get food poisoning?

Unlike viral gastroenteritis, food poisoning is all about what you eat. It can happen to anyone who swallows contaminated food or liquids, and most often occurs when food isn’t cooked properly or has gone bad.

Contaminants that cause food poisoning run the gamut, from bacteria and viruses to parasites, funguses and toxins. Among the more than 250 types of food poisoning, a few common causes stand out:

  • Salmonella. Raw eggs and undercooked poultry are common sources of salmonella poisoning, which is the most prevalent bacterial cause of food poisoning in the U.S.

  • E. coli. This bacteria, usually found in undercooked meat and raw veggies, produce a toxin that irritates the small intestine.

  • Listeria. Food poisoning is sometimes caused by bacteria often found in deli meats, hot dogs, soft cheeses and raw sprouts. Listeria can be especially dangerous for pregnant women.

  • Norovirus. That’s right. The same virus most associated with stomach bugs can also show up in your food. It’s typically caused by eating undercooked shellfish, leafy greens, fresh fruit or by consuming food prepared by someone who is sick.

According to the CDC, around 48 million people experience some type of food poisoning in the U.S. each year. While food poisoning can happen anywhere, it’s especially easy to get when traveling abroad. Whether you’re at home or on the road, it’s always best to avoid eating undercooked meat, fish or eggs and to always get your water from a trusted source.


What are the symptoms of a stomach bug?

Stomach bug symptoms usually develop within 24 to 72 hours of exposure to a virus. Common symptoms of viral gastroenteritis include:

  • Diarrhea.
  • Nausea and vomiting.
  • Stomach cramps, muscle aches, or weakness.
  • Loss of appetite.
  • Low-grade fever.
  • Headache and body aches.
  • Light-headedness or dizziness.

Stomach bug symptoms will usually clear up within 2 to 8 days, depending on the virus that causes it. More severe cases could last up to 2 weeks.


What are the symptoms of food poisoning?

In general, food poisoning symptoms kick in much faster than when you have a stomach bug, usually between 30 minutes to 8 hours after exposure. The good news is they also run their course more quickly. For healthy individuals, it usually takes 12 to 48 hours for the body to purge the infection.

Signs of food poisoning can vary depending on what you ingest. The most common symptoms include:

  • Diarrhea.
  • Nausea and vomiting.
  • Stomach pain or cramping.
  • Fever.
  • Headache.
  • Weakness.

Food poisoning is typically not serious, and most people recover on their own within a few days. However, people with weaker immune systems are at higher risk for severe infection, including:

  • Children under age of 5
  • Adults over the age of 65
  • Pregnant women.
  • Individuals with chronic illnesses, including infections, cancer, immunodeficiency diseases and autoimmune diseases.

Certain medications can also impact your immunity and make you more prone to illness, including corticosteroids and immunosuppressants.


Does COVID-19 cause gastrointestinal issues?

While respiratory issues are typically associated with COVID-19, vomiting, nausea and diarrhea can sometimes be a sign of the virus. Here are some not-so-fun facts about upset stomachs and COVID:

  • Around 5-10 percent of adults with COVID report GI symptoms, which are usually the first signs of the virus.

  • Diarrhea caused by COVID is typically very watery and may appear yellow or green.

  • Additional COVID symptoms usually develop within a day or two, including fever, cough, congestion and/or loss of taste and smell.

Think you might have COVID? Don’t wait it out. Our Indigo Health providers will get you evaluated, tested and on your way with a custom treatment plan and same-day results. Learn more about Indigo’s COVID testing options.


How can I prevent stomach bugs?

Viral gastroenteritis is highly contagious. To protect yourself and prevent its spread, take these simple steps:

  • Wash hands frequently with soap and water.
  • Handle and prepare food safely.
  • Clean and disinfect surfaces, particularly high-touch areas.
  • Thoroughly wash any contaminated clothes or bedding.
  • When you’re sick, stay home and stay away from others. The easiest way to catch the bug is through direct contact with someone who is ill.


How can I prevent food poisoning?

The CDC recommends four steps to prevent food poisoning:

  • Clean. Germs can survive in loads of places around your kitchen, including your hands, utensils, cutting boards and countertops. Wash hands and surfaces before, during and after food prep.

  • Separate. Separate raw meat, poultry, seafood and eggs from ready-to-eat foods. Use separate cutting boards and keep raw meat away from other foods in your shopping cart and refrigerator.

  • Cook. Cook food to the right internal temperature to kill harmful bacteria.
  • Chill. Set your refrigerator at 40°F or below and refrigerate leftovers within 2 hours of cooking (or within 1 hour if food is exposed to temperatures above 90°F).


How do you treat stomach bugs and food poisoning?

There’s often no specific medical treatment for viral gastroenteritis or food poisoning. Whether you’d laid low by a viral infection or a dicey seafood omelet, your symptoms should run their course within a few days.

The best plan of attack is to take care of your body while it does its job to battle infection. Here are a few simple things that you can do at home to speed up your recovery:

  • Drink plenty of liquids. Your body loses a ton of fluids when you have diarrhea, vomiting or both. To avoid dehydration, frequently sip as much water as your body can tolerate. Over-the-counter hydration formulas, such as Pedialyte or DripDrop, are great options (at any age) to replenish nutrients and electrolytes. While sports drinks can do the same, some can be high in sugar.

  • Stick to bland foods. When you feel like you’re able get something down, slow and simple is the best way to go.

    • Eat bland, easy-to-digest foods to allow your stomach to settle. The BRAT diet (bananas, rice, applesauce and toast) goes easy on the tummy, offers needed nutrients and helps boost energy.

    • If your illness was severe, avoid dairy products, caffeine, alcohol, sugar, fiber and greasy or highly seasoned foods for a few days after your symptoms have resolved.

  • Take it easy. A stomach bug or food poisoning can take a lot out of you – literally. Your body needs plenty of rest to recover.


Lingering stomach symptoms? Indigo Urgent Care is here

If you have moderate symptoms from a suspected stomach bug or food poisoning that don’t improve after a couple of days, it’s a good idea to visit your nearby Indigo Urgent Care. We’re here 8 am to 8 pm every day, including holidays. Simply walk into one of our convenient neighborhood locations or book an appointment online.

If a trip to one of our clinics doesn’t sit right with your upset stomach, rest easy. You can schedule an online care appointment and be seen by a provider from the comfort of your bed or couch.

Some stomach bugs and cases of food poisoning can be severe, and complications can arise. You should visit your nearest emergency department if you or a loved one have any of the following symptoms:

  • Bloody stool or bloody vomit
  • Inability to keep any fluids down
  • Signs of dehydration (dizziness, headache, lethargy, fatigue, infrequent urination, and dry mouth, lips and eyes)
  • Fever above 104o F
  • Severe abdominal pain

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