Infections are part of everyday life, and they can happen when bacteria, viruses, or other germs find their way into your body and begin to multiply. Your immune system typically works to fight off these germs, but sometimes they can overwhelm your defenses, leading to an infection. Knowing the signs of an infection is essential so you can recognize when it’s time to see a doctor or take action.

Signs You Might Have an Infection Depend on Its Location and Type

The specific signs of an infection can vary depending on where it’s happening in your body and the type of germ involved. However, there are some common symptoms that often appear across many kinds of infections.

You Might Develop a Fever

One of the clearest signs of an infection is a fever. Your body temperature rises as a natural response to help fight off the germs. A fever is the body’s way of turning up the heat to create an environment that’s harder for germs to thrive in. Most of the time, fevers are mild, but if your temperature goes above 103°F (39.4°C), it’s a sign that you should definitely seek medical attention.

You Could Notice Swelling or Redness

If the infection is in a specific area—like a cut, sore, or insect bite—you might notice redness, swelling, or warmth around that spot. This happens because your immune system sends extra blood flow to that area to help fight off the germs. Swollen lymph nodes, which are small glands in your neck, underarms, or groin, can also indicate your body is dealing with an infection.

You May Feel Tired and Fatigued

Fatigue is another common sign of an infection. Your body works hard to fight off germs, which can leave you feeling exhausted. This tiredness is a result of your immune system using extra energy to help fight the infection.

You Might Have Pain or Discomfort

Pain is often a signal that something isn’t quite right in your body. Pain or tenderness can come along with infections, especially if they involve tissues that are inflamed. For instance, an infected ear might cause an earache, while an infected tooth might cause sharp or throbbing pain.

You Could Develop Pus or Discharge

If you have an infection in your skin or an open wound, you might notice pus or discharge. Pus is a thick, yellowish fluid that’s a mixture of dead cells, germs, and tissue. It’s a sign that your body is actively trying to get rid of the infection.

You May Have Coughing or Difficulty Breathing

Respiratory infections, like pneumonia or bronchitis, often come with coughing, difficulty breathing, or a feeling of tightness in your chest. These symptoms are signs that your respiratory system is dealing with germs that shouldn’t be there.

How Do You Know If It’s Time to See a Doctor?

Some mild infections clear up on their own, but it’s important to know when to seek medical attention. If you experience any of the following signs, you should consider seeing a doctor:

High fever: Especially if it’s above 103°F or doesn’t come down with over-the-counter medications.
Severe pain: Pain that keeps getting worse or doesn’t go away.
Persistent symptoms: If your symptoms don’t improve after a few days or if they worsen over time.
Difficulty breathing: Shortness of breath or chest pain can be a sign of a more serious infection that requires prompt attention.

Types of Infections and Their Specific Signs

Skin Infections: Look for Redness, Swelling, and Pain

Skin infections, like cellulitis or abscesses, often present as areas of redness, warmth, swelling, and sometimes pus. The skin might feel hot to the touch, and the infected area could be tender.

Respiratory Infections: Cough, Congestion, and Shortness of Breath

For respiratory infections like the flu, pneumonia, or bronchitis, you’ll often have symptoms such as coughing, wheezing, sore throat, and congestion. These infections can also lead to fever and a general feeling of being unwell.

Urinary Tract Infections: Pain When You Pee and Cloudy Urine

Urinary tract infections (UTIs) usually cause pain or a burning sensation when urinating, the need to urinate frequently, and cloudy or foul-smelling urine. Lower belly pain or discomfort might also be present.

Ear Infections: Earache and Fluid Drainage

Ear infections can cause ear pain, difficulty hearing, and sometimes fluid drainage from the ear. Children with ear infections might also be irritable or have trouble sleeping.

What Causes Infections in the First Place?

Infections are caused by microorganisms like bacteria, viruses, fungi, or parasites. Here’s a quick look at each type:

Bacteria: These are single-celled organisms that can cause infections like strep throat, UTIs, and some skin infections. Antibiotics are typically used to treat bacterial infections.
Viruses: Viruses are much smaller than bacteria and need to invade a host cell to reproduce. They cause illnesses like the flu, the common cold, and COVID-19. Viral infections usually have to run their course, though antiviral medications can sometimes help.
Fungi: Fungi are responsible for infections like athlete’s foot or ringworm. Antifungal medications are used for these infections.
Parasites: Parasites are organisms that live in or on a host, causing diseases like malaria or giardiasis.

How Can You Prevent Infections?

Prevention is always better than treatment, and there are many ways to reduce your risk of getting an infection:

Wash your hands: Regular handwashing with soap and water helps stop the spread of germs.
Keep wounds clean: If you have a cut or scrape, make sure to clean it well and cover it to keep out bacteria.
Vaccinate: Vaccines help protect against many common viral infections, like the flu or measles.
Stay hydrated and eat well: A healthy immune system is better at fighting infections, so it’s important to eat a balanced diet and drink plenty of fluids.
Avoid close contact: If someone around you is sick, keeping your distance can help prevent catching their germs.