Everyone will get an infection at some point in their lives. Learn what causes them, how to treat them and how to protect yourself.

1. What is an infection?
2. How are infections spread?
3. What causes an infection?
4. How are infections treated?
5. What are some of the symptoms of an infection?
6. When can I see a doctor for an infection?
7. How can I tell if a wound is infected?
8. How can I protect myself against infections?
9. How can my health insurance help treat and prevent infections?

The word “infection” might conjure up a lot of scary images in your head. But infections are very common — virtually everyone will get one at some point in their life. Infections include everything from common colds to warts to yeast infections.

It’s true, some infections can be nasty and even deadly. But your immune system is very good at fighting off most infections. That’s exactly what it’s built for. And if it’s having some trouble, there are medications you can get to help fight off infections too.

There are also many things you can do to prevent infections. Read on to learn about what causes infections, how they’re treated, and what you can do to protect yourself.

What is an infection?

“An infection is the invasion and growth of germs in the body that leads to health issues,” explains Nima Majlesi, D.O. He’s the director of medical toxicology at Staten Island University Hospital in New York.

Those germs can be things like:

• Bacteria
• Fungi
• Microorganisms
• Viruses

The infection can begin anywhere in your body and spread to other places.

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How are infections spread?

Germs are all around us. For an infection to happen, germs need to make their way into a vulnerable part of your body. Here are some common ways that infection-causing germs can spread:

• Direct contact. Infections can spread from one person to another through direct contact with their skin, mucous membranes (the moist inner linings of some organs and body cavities) or bodily fluids.
• Indirect contact. You can also get infections from other people indirectly. An infected person can leave germs on a surface like a door handle or countertop. You can pick up those germs when you touch that surface. Then if you touch your eyes, nose or mouth, you can end up infected too.
• Bug bites. Many insects can carry diseases and spread them to you with a bite. Mosquitoes and ticks are common carriers of diseases that can infect humans.
• Food. Infectious germs can live on food and cause infections when you eat them.
• Through the air. Germs can be carried in the air in tiny water droplets or dust. Then they can get into your nose, mouth and lungs when you breathe.

What causes an infection?

There are 4 types of germs that can cause infections, and the infections they can cause vary from mild to severe. Here’s a look at them:

1. Viral infections. You’ve heard a lot about COVID-19 in recent years, which is a type of viral infection. Many colds and upper respiratory infections, including the flu, are also caused by viruses. And viruses are responsible for lots of other infections as well, such as:

• Human immunodeficiency virus (HIV), which can lead to acquired immunodeficiency syndrome (AIDS). Both attack your immune system, weakening your body’s ability to fight off infections and diseases.
• Warts. These are caused by a type of human papillomavirus (HPV). There are more than 150 different kinds of HPV viruses. Some are spread through sex and cause genital warts. HPV infections are also the leading cause of cervical cancer.
• Hepatitis A, B and C viruses cause liver disease and even liver cancer.
• Chicken pox. This common childhood illness is caused by the varicella-zoster virus. After a chicken pox infection, the virus stays in your body, inactive, and can cause shingles later in life.

2. Bacterial infections. Bacteria are what you might think of first when you think of germs. They are everywhere, including on and inside your body. In fact, you host trillions of bacteria on your skin and in your guts. Most of them are harmless, and many are beneficial to you. But there are also many bad bacteria that can cause infections.

“These typically invade an area and wreak havoc, along with causing fever and malaise,” explains Dr. Majlesi. Common bacterial infections include:

• Strep throat, a type of infection that makes your throat feel sore and scratchy.
• Staph infections, which are caused by staphylococcus bacteria. Many people carry this type of bacteria on their skin, but it only causes an infection if it gets into an open wound.
• Urinary tract infections, which happen when bacteria enter the urethra (the tube that moves urine from your bladder out of your body).

3. Fungal infections. Fungi include mold, yeast and mushrooms. Most are harmless (you can eat them!), but some can cause infections. Fungi most often infect the skin or mucosal tissue such as the mouth or vagina. Common fungal infections include:

• Athlete’s foot, a scaly rash that often starts between the toes.
• Fungal nail infections, which cause yellowed, thickened and ragged nails.
• Ringworm, a contagious infection that causes a red, circular rash.
• Yeast infections. These are caused by the yeast candida. It can also cause an infection called thrush in the mouth, throat or esophagus.

4. Parasitic infections. Parasites are organisms that live on a host organism (sometimes you). They feed off the host, causing harm to them. Parasites include microscopic organisms as well as larger bugs such as parasitic worms and fleas. Parasitic infections include:

• Malaria. This serious and sometimes deadly illness is caused by a bloodborne parasite that is spread by mosquitoes.
• Parasitic worms such as tapeworms, flatworms and pinworms. These parasites live in the intestinal tract and can cause you to become malnourished.
• Recreational water illnesses such as diarrhea can be caused by parasites in swimming pools, hot tubs, lakes, rivers or the ocean.

Most infections are caused by just one of these germs, but bacteria and viruses can cause similar infections. For example, the following infections can be caused by viruses or bacteria:

• Pneumonia (an infection in the lungs). Fungal infection can also cause pneumonia.
• Meningitis (swelling of the membrane around the brain and spinal cord). It can also be caused by fungal infections, but that’s rare.
• Food poisoning. Norovirus is a highly contagious type of food poisoning caused by a virus. Most other foodborne illnesses are caused by bacteria. Parasitic infections can also come from food.

How are infections treated?

How you treat an infection depends on whether it’s caused by a virus, bacteria, fungus or parasite. You might think of antibiotics as the go-to medicine for infections. But antibiotics are effective only against bacterial infections, not viral, fungal or parasitic ones. Here’s how to treat each kind of infection.

How to treat viral infections. Many viral infections, such as the common cold or the flu, don’t require treatment. But your doctor may recommend things, such as pain relievers, to manage symptoms while your body fights off the virus.

There are antiviral medicines that can treat some viral infections, such as herpes, HIV and COVID-19, says Dr. Majlesi. There are also vaccines for many viruses that can prevent infection in the first place.

How to treat bacterial infections. Bacterial infections can be treated by antibiotics, which kill off bacteria. Your doctor might not always prescribe an antibiotic if you have a bacterial infection. Many infections are mild enough that you can let them run their course while your immune system fights it off.

It’s important to use antibiotics only as directed by your doctor. Antibiotics can cause side effects, such as rashes, diarrhea or yeast infections. Overuse of antibiotics can also lead to antibiotic resistance. The more you use antibiotics, the more bacteria adapt to resist them, making bacterial infections harder to treat.

For infections that can be viral or bacterial (such as pneumonia), your doctor may run tests to figure out exactly what is causing the infection. That way they can determine whether antibiotics will help.

How to treat fungal and parasitic infections. Antifungal medicines are used to treat fungal infections, and antiparasitic medications are used to treat parasites, says Dr. Majlesi. Many common fungal and parasitic infections (such as lice) can be treated at home with over-the-counter medicines. Talk to your doctor about more serious or persistent infections or if you suspect you have intestinal worms.

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What are some of the symptoms of an infection?

The symptoms of an infection depend on what’s causing it and where it’s located. Some common signs of infection include:

• Chills and sweats
• Coughing or sore throat
• Diarrhea
• Shortness of breath
• Fever

When can I see a doctor for an infection?

Before you head to urgent care or schedule an appointment with your doctor, you might call the office first and talk to a nurse about your symptoms. Your health plan may also have an option for virtual care (telehealth) or a nurse hotline you can call. They can assess your symptoms over the phone and help you decide whether you need to see a doctor.

If you experience any of these symptoms, it’s a good idea to contact your doctor right away:

• A very high fever (104° F or higher), or any fever accompanied by seizures, loss of consciousness, confusion, stiff neck, trouble breathing, or severe pain or swelling anywhere on your body
• Chest pain, shortness of breath or pain when breathing
• Symptoms that don’t get better or get worse after 10 days
• Symptoms that improve but then get worse again
• Dehydration
• Any symptom that is severe enough to make you worry

How can I tell if a wound is infected?

Your body goes to work immediately to heal cuts and scrapes and fight off germs that make their way into the wound. The infected tissue may produce a clear discharge. This is a normal part of the healing process.

But if the wound does not start to look better in a few days, it may be infected. Other signs of infection include:

• Discharge that is discolored (yellow or greenish) and smells bad
• Fever
• Redness, pain, swelling, or bleeding at the wound site

If you notice any of these signs, contact your doctor right away.

How can I protect myself against infections?

There are many things you can do to protect yourself from infections, such as practicing good hygiene and safe food handling. Here’s how:

Practice good hygiene. A great way to avoid infections is simply to practice good hygiene:

• Wash your hands often. When it comes to washing your hands, there’s never too much of a good thing. Make sure you do it the right way: Lather up with soap and rub it into the palms and backs of your hands (don’t forget your fingertips, under your nails and between your fingers). Scrub for at least 20 seconds, then rinse and dry them, using a clean towel. If you don’t have access to running water, use an alcohol-based hand sanitizer.
• Avoid touching your eyes, nose and mouth. Your hands are constantly picking up germs from your surroundings. Touching your eyes, nose and mouth can transmit those germs into your body and cause an infection.
• Clean all cuts and scrapes well. Make sure your own hands are clean first, then wash the wound with soap and water. Apply an antibiotic ointment or petroleum jelly to protect against bacteria, and then top it with a bandage. More serious wounds such as deep or gaping cuts, severe burns or bites should be treated by a doctor.
• Don’t be a pimple popper. Yes, it’s tempting, but it can lead to infection.
• Don’t share dishes, glasses or eating utensils.
• Cover your cough. Cough into your elbow, not your hands. That will prevent germs from spreading from your hands to other surfaces.
• Wear a mask. If you’re immunocompromised or don’t want to be infected with other people’s germs, you might want to wear a mask on public transportation, trains, airplanes and in large gatherings. They may help protect you from other airborne infections.

Follow food safety practices. Handling food safely can help prevent infections from foodborne pathogens. Safety measures include:

• Rinsing fresh fruits and veggies under running water before you cook or eat them.
• Washing your hands thoroughly after you touch raw meat. Use separate utensils and cutting boards for raw meat, and then wash them well with very hot water and soap.
• Cooking meat to the right temperature and using a meat thermometer. The proper temperature depends on the meat:
  • All poultry and ground poultry should be cooked to 165° F.
  • Beef, pork and lamb roasts and steaks should be cooked to 145° F.
  • Ground meat should be cooked to 160° F.
  • Fish should be cooked to 145° F. (Shellfish flesh should be pearly and opaque.)
  • Reheat leftovers to 165° F.
• Don’t defrost food on the counter. Use your fridge or microwave.

Stay up to date on your vaccines. Vaccines are key to protecting you against many common viruses and bacteria that can cause serious infections. If you have kids, make sure they receive all the recommended childhood vaccinations. That includes:

• HepB (hepatitis B)
• DTaP (diphtheria, tetanus and pertussis)
• Hib (Haemophilus influenzae type b)
• IPV (inactivated poliovirus)
• PCV (pneumococcal conjugate)
• RV (rotavirus)
• VAR (varicella, which is chicken pox)
• HepA (hepatitis A)
• MMR (measles, mumps, rubella)
• HPV (human papillomavirus)
• MenACWY (meningococcal disease)

Make sure all your vaccinations are up to date too. That includes:

• Seasonal flu (recommended for children and adults every year)
• COVID-19 (all adults and children over 6 months can get the initial dose; adults and children over 5 can get booster shots as recommended by the Centers for Disease Control and Prevention or your doctor)
• Tetanus or Tdap (booster shots are needed every 10 years)
• Hepatitis B (if you didn’t get it as a child)
• Shingles (recommended for adults over 50)

If you plan to travel abroad, ask your doctor if you need any other vaccines or boosters.

Practice safe sex. Practicing safe sex can protect you against many sexually transmitted infections (STIs), including:

• Chlamydia (causes genital discharge and burning during urination, though some cases may cause no symptoms)
• Gonorrhea (causes genital discharge and burning during urination)
• Herpes (causes sores on the genitals and/or mouth)
• HIV/AIDS (a deadly disease that affects the immune system)

Condoms are highly effective at preventing STIs during vaginal, anal or oral sex. If you are not in a monogamous relationship, get tested for STIs regularly and ask new partners if they have been tested.

Protect yourself against mosquitoes and ticks. They can carry both viruses and bacteria. Mosquitoes can carry several diseases, including malaria and the Zika virus. Ticks can transmit Lyme disease, a bacterial infection that can cause severe illness if not treated early.

Use insect repellents approved by the Environmental Protection Agency when you’re outside in places with a lot of mosquitoes. If you live in an area where ticks are common, check your clothing and body for these bugs when you come in from the outdoors, even if you’ve only been hanging out in your backyard.

Keep your immune system strong. Even with all these precautions, germs are unavoidable. But a strong immune system can fight them, helping to prevent infection or lessen its severity.

Eating lots of fruits, vegetables and other plant foods provides vital nutrients, such as vitamin C, that your immune system needs to fight infection. These foods are also a good source of fiber, which supports good microbes in your gut. Growing research is finding that our gut microbes play a major role in regulating our immune system and fighting infections.

Smoking and drinking too much alcohol can weaken the immune system. If you smoke, talk to your doctor about strategies to quit. If you drink, do so only in moderation. That means no more than 1 drink per day for women and no more than 2 per day for men.

How can my health insurance help treat and prevent infections?

If you come down with an infection, you’ll want a health insurance plan that can cover the care you need. Your primary care physician (PCP) will be your go-to person for diagnosing and treating an infection (or referring you to a specialist to treat it further, if needed).

Your health plan can help cover any doctor’s visits or medications you need to recuperate. You’ll only pay a copay or coinsurance in most cases, and your deductible may apply. Many health plans also provide virtual care, meaning you can potentially get the help you need without leaving your home.

Many health plans also cover preventive care, such as vaccines — usually at no cost to you — so that you can help prevent infections from happening in the first place.

Think you may have an infection? You can talk to a doctor without leaving your home. Learn about virtual visit options today, or call a licensed insurance agent at 1-844-211-7730 for more information.

For informational purposes only. This information is compiled by UnitedHealthcare, and/or one of its affiliates, and does not diagnose problems or recommend specific treatment. Services and medical technologies referenced herein may not be covered under your plan. Please consult directly with your primary care physician if you need medical advice.

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