The symptoms of a bacterial infection will often depend on the location of the infection in the body. However, some common general symptoms include fever, fatigue, and swollen lymph nodes.

Certain disease-causing bacteria can sometimes enter the body. Once inside, they may multiply and cause an infection that can result in a number of symptoms.

This article will outline some of the signs and symptoms of bacterial infections according to where they occur in the body. It will also provide information on treating and preventing bacterial infections and offer advice on when to see a doctor.

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General symptoms of a bacterial infection include fever, chills, exhaustion, and headache.

The signs and symptoms of a bacterial infection typically depend on where in the body the infection occurs.

However, some of the most common general signs and symptoms of infection include:

Bacterial infections can develop anywhere in the body, but they often occur near sites where bacteria can enter the body.

The sections below will outline some of the most common signs and symptoms associated with bacterial infections in different parts of the body.

Gastrointestinal infections

Although different species of bacteria cause slightly different symptoms, most tend to cause several of the following:

  • pain and tenderness in the stomach
  • nausea and vomiting
  • loss of appetite
  • frequent bowel movements
  • diarrhea that can be loose, watery, or bloody
  • feeling the need to go to the bathroom even when the bowel is empty
  • inflammation of the colon
  • fever

Upper respiratory tract infections

The upper respiratory tract includes the nasal passages and the sinuses. The sinuses are a network of hollow cavities inside the skull.

Sometimes, the sinuses can become infected with bacteria or viruses. The medical term for infection and inflammation of the sinuses is sinusitis.

Common signs and symptoms of sinusitis include:

Lower respiratory tract infections

The lower respiratory tract consists of the following body parts:

  • the trachea, or windpipe
  • the bronchi, which are airways that lead from the trachea to the lungs
  • the lungs

One of the most common bacterial lung infections is bacterial pneumonia. Some potential signs and symptoms of pneumonia include:

  • a cough that may produce green, yellow, or bloody mucus
  • rapid, shallow breathing
  • sharp or stabbing chest pain that worsens when breathing deeply or coughing
  • shortness of breath
  • fever
  • chills
  • unexplained exhaustion and low energy
  • nausea and vomiting, particularly in young children
  • confusion, particularly in older adults

Ear infections

Bacterial infections can occur in the inner, middle, or outer part of the ear.

The symptoms of an ear infection usually come on very quickly and may include:

  • pain or pressure inside the ear
  • a feeling of fullness inside the ear
  • drainage from the ear
  • itching and irritation in and around the ear
  • scaliness of the skin around the ear
  • partial hearing loss
  • fever
  • a lack of energy

Throat infections

The bacteria group A Streptococcus can cause a bacterial infection of the throat and tonsils. Another term for this condition is strep throat.

The most common symptoms of strep throat include:

  • a sore throat
  • pain when swallowing
  • tiny red dots along the roof of the mouth
  • discoloration and swelling of the tonsils
  • swollen lymph nodes in the front of the neck
  • fever

Strep throat is much more common in children and adolescents. In the United States, as many as 3 in 10 children who experience a sore throat have strep throat.

Vaginal infections

Bacterial vaginosis (BV) is a bacterial infection of the vagina. It is a common vaginal condition in women aged 15–44 years.

Signs and symptoms of bacterial vaginosis include:

  • thin white or gray vaginal discharge
  • pain, itching, or burning inside the vagina
  • itching around the vagina
  • burning sensations when urinating
  • a strong, fishy-smelling odor, especially after sex

Sexually transmitted infections

A number of sexually transmitted infections (STIs) develop due to bacteria. Most bacterial STIs can infect anyone.

Some common bacterial STIs include:

Although each STI causes slightly different symptoms, most can cause the following:

  • abnormal genital discharge that may be:
    • foul-smelling
    • discolored
    • bloody
    • an unusual consistency
  • itchy skin around the genitals
  • pain during and after sex
  • pain or burning sensations while urinating
  • painful bowel movements
  • rectal pain or bleeding
  • vaginal bleeding not related to menstruation
  • swollen lymph nodes
  • fever

Skin infections

Most skin infections develop when bacteria enter the body through breaks in the skin. These breaks may occur as a result of surgical incisions or injuries such as cuts, scrapes, and burns.

Two common skin infections are cellulitis and impetigo.


Cellulitis is a common skin infection in which bacteria infect the deeper layers of the skin. It typically affects one of the limbs.

Some signs and symptoms of cellulitis include:

  • flushed, swollen, and painful areas that are warm and tender
  • areas where the skin looks pitted or resembles orange peel
  • blisters that may ooze or leak pus
  • delayed wound healing
  • swollen lymph nodes
  • fever and chills


Impetigo is another common bacterial skin infection. It typically affects the face and hands but may also affect other parts of the body.

Impetigo causes flushed, itchy sores that leak clear fluid. Over the course of several days, the sores crust over to form honey colored scabs.

Other possible signs and symptoms of impetigo include:

  • swelling of the lymph nodes
  • fever
  • malaise

Urinary tract infections

Urinary tract infections (UTIs) are bacterial infections that develop somewhere within the urinary system.

These infections affect around 60% of women and 12% of men at least once in their lifetime.

Signs and symptoms of a UTI include:

  • pain in the lower abdomen, pelvic area, and lower back
  • cloudy, foul-smelling urine
  • feeling the need to urinate more often than normal
  • feeling a strong urge to urinate but being unable to produce much urine
  • pain or burning sensations while urinating
  • a feeling of incomplete bladder emptying following urination
  • urine leakage

A UTI that affects the kidneys may cause additional symptoms, such as:

  • fever
  • nausea and vomiting
  • upper back pain, often on one side of the body

Brain and spinal cord infections

Meningococcal meningitis is the medical term for a bacterial infection of the lining of the brain and spinal cord. It is a life threatening condition that requires urgent medical treatment.

Signs and symptoms of meningitis include:

  • fever
  • headache
  • a stiff neck
  • sensitivity to light
  • nausea and vomiting
  • confusion

Some possible symptoms of meningitis in infants and babies include:

  • inactivity or slowness
  • vomiting
  • feeding poorly
  • bulging in the soft spot of the skull

Blood infections

Any severe or untreated bacterial infection can trigger an exaggerated immune response called sepsis. This condition can lead to tissue damage, organ failure, and death.

Some signs and symptoms of sepsis include:

  • fever or chills
  • clammy, sweaty skin
  • an increased heart rate
  • shortness of breath
  • extreme pain and discomfort
  • confusion or disorientation

Knowing which type of microbe is causing symptoms is critical to receiving appropriate treatment.

The treatment for bacterial infections is usually a course of antibiotics. Doctors may prescribe antiviral medications for certain viral infections, but few antiviral medications exist.

There are some illnesses that tend to develop due to either bacteria or viruses.

Infections typically due to bacteria include:

Infections typically due to viruses include:

Learn more about the differences between bacterial and viral infections here.

Most bacterial infections require treatment with antibiotics. The type of antibiotic a doctor prescribes for a particular bacterial infection will usually depend on:

  • the type, severity, and location of the infection
  • whether or not the bacterial species is resistant to certain classes of antibiotics
  • whether or not the person has used the antibiotic before
  • whether or not the person is allergic to antibiotics or any of their ingredients
  • whether or not the person has any other health conditions

Antibiotics are available in various forms. A person can take them orally in the form of pills or apply them topically in the form of creams or ointments.

If a person has a severe bacterial infection, they may require intravenous antibiotics.

Practicing good hygiene is the best way to help prevent bacterial infections. Good hygiene means washing the hands and body thoroughly and frequently, as well as keeping all personal items clean.

Some other prevention tips include:

  • covering the mouth and nose when coughing or sneezing
  • keeping all cuts, burns, and sores clean and covered with sterile gauze or a bandage
  • staying hydrated and using moisturizers to prevent cracked skin
  • not sharing personal items with others
  • using a barrier method of contraception during sex
  • cooking meat thoroughly and keeping perishable items refrigerated

Anyone who thinks that they have a bacterial infection should talk with a doctor, especially if their symptoms persist or worsen.

Most bacterial infections resolve with prompt treatment and do not cause any further complications. However, untreated or improperly treated infections can become severe and may cause life threatening complications.

A person should seek prompt medical care if they experience any of the following symptoms:

  • severe pain
  • pain during urination, bowel movements, or sex
  • abnormal genital discharge
  • sores that are large, very painful, or oozing pus
  • abnormal rashes
  • severe or chronic diarrhea
  • high fever and chills
  • an abnormally fast or slow heart rate
  • severe breathing difficulties
  • cold hands and feet
  • blue or purple discoloration of the lips or extremities
  • confusion or disorientation
  • loss of consciousness

Certain groups are more likely to develop severe infections or complications. At-risk populations who generally require more intensive care or monitoring include:

  • infants and young children
  • people over 65 years of age
  • people with weakened immune systems
  • people taking immunosuppressive treatments or medications
  • people who recently had surgery or are still recovering from surgery

Bacterial infections can cause some general symptoms, such as pain, fever, and swollen lymph nodes. They may also cause some other symptoms depending on where in the body they occur.

Bacterial infections typically require treatment with antibiotics. The type of antibiotic a person receives will depend on the location and severity of the infection they have.

Untreated bacterial infections can cause severe or life threatening complications. A person should see their doctor if they experience any symptoms that warrant prompt medical care or if their existing symptoms persist or worsen.