What Is Pseudomonas aeruginosa? Symptoms, Causes, Diagnosis, Treatment, and Prevention
Health ConditionsInfectious Diseases

What Is Pseudomonas aeruginosa?

What Is Pseudomonas aeruginosa?
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Updated on December 11, 2025
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Pseudomonas is a group of bacteria that can cause various types of infections.

Pseudomonas aeruginosa is the most common disease-causing form of this bacteria, according to the Centers for Disease Control and Prevention (CDC).

Serious infections from P. aeruginosa primarily occur in healthcare settings, but you can also develop infections from hot tubs and swimming pools.

Signs and Symptoms of Pseudomonas aeruginosa

Symptoms of P. aeruginosa vary depending on the type of infection. It may cause:

  • Infection of the lungs (pneumonia)
  • Fever and chills
  • Difficulty breathing
  • Tiredness
  • Cough, sometimes with yellow, green, or bloody mucus

Urinary tract infections can cause:

  • Strong urge to urinate frequently
  • Painful urination
  • Unpleasant odor in urine
  • Cloudy or bloody urine
  • Pain in the pelvic area

Wound infections can cause:

  • Inflamed wound site
  • Fluid leakage from wound

Ear infections (like swimmer’s ear) can cause:

  • Ear pain
  • Decreased hearing
  • Redness or swelling of outer ear

Causes and Risk Factors of Pseudomonas aeruginosa

In healthcare settings, P. aeruginosa can be spread through improper hygiene, such as from the unclean hands of healthcare workers, or via contaminated medical equipment that wasn't fully sterilized.

 The bacteria can also live on your skin or in your throat without causing a problem until another illness makes your body vulnerable to infection.

Common hospital-associated P. aeruginosa infections include bloodstream infections, pneumonia, urinary tract infections, and surgical wound infections.

These infections typically affect people who are ill in the hospital, particularly those with weakened immune systems from diseases or long-term treatments.

When hospitalized, you have a higher risk of a serious, life-threatening P. aeruginosa infection if you have surgical wounds or burns, or are being treated with a breathing machine, such as a mechanical ventilator, or other medical devices, such as urinary or intravenous catheters.

Exposure to contaminated water can also cause mild P. aeruginosa infections in healthy people. For instance, inadequately disinfected hot tubs and swimming pools can cause P. aeruginosa ear infections and skin rashes. The bacteria can also cause eye infections in users of contact lenses.

How Is Pseudomonas aeruginosa Diagnosed?

To diagnose P. aeruginosa, your doctor will perform a physical exam and ask about your symptoms and medical history. Then they’ll send a sample of your blood or other bodily fluid to a lab to test for the bacteria.

A test may also be done to determine which antibiotics will be most effective.

Treatment and Medication Options for Pseudomonas aeruginosa

Mild, water-related P. aeruginosa infections are generally treated easily with certain antibiotics.

Antibiotics are usually administered for between 7 and 14 days, and sometimes longer, depending on the type and severity of the infection.

Treating severe hospital-associated P. aeruginosa infections is becoming more difficult, however, because some bacterial strains show resistance to nearly all classes of powerful antibiotics. Treating these drug-resistant infections requires sending samples to a laboratory to test the bacteria against different antibiotics in hopes of finding drugs that are effective.

Before the lab confirms which particular drugs will work, you may be given a combination of several antibiotics.

Prevention of Pseudomonas aeruginosa

To prevent P. aeruginosa, there are several steps you can take.

  • Wash your hands often. This is the best way to prevent the spread of germs. Use soap and water and scrub for at least 20 seconds, or use an alcohol-based hand sanitizer.
  • Keep wounds clean. If you get a cut or scrape, be sure to clean it and cover it with a bandage.
  • Avoid sharing personal items. Don’t let others use personal items like razors or towels.
  • Use antibiotics only as needed. If your doctor prescribes antibiotics, take the meds as prescribed.
  • Remind others to wash their hands. If you’re in the hospital, ask visitors, doctors, and nurses to wash their hands before touching you.
  • Keep surfaces clean. Disinfect all the surfaces you touch, such as your cell phone, doorknobs, and light switches.
  • Swim safely. If you’re going into a hot tub or pool, make sure it is properly chlorinated and maintained.

Pseudomonas aeruginosa Prognosis

Prognosis depends on what type of infection a person has, their overall health, and the type of care they receive. The mortality rates for P. aeruginosa infections are estimated to range from 18 to 61 percent.

 Outcomes tend to be worse for infections in the bloodstream or lungs, and for people with underlying cardiovascular disease or cancers of the blood. It’s crucial to get timely treatment with the right antibiotic.

Complications of Pseudomonas aeruginosa

If a wound leads to a pseudomonas infection and goes untreated, it could result in infection in the bones. Pseudomonal infections that enter the bloodstream can also lead to respiratory failure, shock, and death.

Research and Statistics: Who Has Pseudomonas aeruginosa

Being in a healthcare setting puts you at the highest risk of P. aeruginosa. In 2017, P. aeruginosa caused approximately 32,600 infections among patients in hospitals and 2,700 deaths in the United States, according to the CDC.

Patients who are on breathing machines, catheters, and those with wounds are at especially high risk. Research has found Pseudomonas is one of the main causes of pneumonia for people on mechanical ventilators.

Related Conditions

People with cystic fibrosis are highly susceptible to pseudomonal lung infections. Indeed, approximately one fourth of all people with cystic fibrosis are infected chronically with the bacteria, according to the Cystic Fibrosis Foundation.

Those who are immunocompromised — meaning those with weakened immune systems — are very vulnerable to P. aeruginosa. This includes people with HIV, cancer and transplant patients, people taking drugs that suppress the immune system, and those with a disease that affects the immune system.

The Takeaway

  • Infections from Pseudomonas aeruginosa can range from mild skin rashes to severe hospital-acquired infections.
  • Proper hygiene and caution in shared environments such as hot tubs and swimming pools will help reduce your risk.
  • Be sure to wash your hands frequently and keep wounds clean to prevent bacterial infections.

FAQ

What causes Pseudomonas aeruginosa in humans?
P. aeruginosa is often found in hospital settings and can be spread through contaminated hands or medical equipment. People can also develop infections from hot tubs and swimming pools.

It can cause pneumonia, urinary tract infections, and wound, ear, and bloodstream infections. Those already with diseases, such as cystic fibrosis, HIV, diabetes, and cancer, may be at a higher risk for developing a P. aeruginosa infection due to a compromised immune system.

P. aeruginosa is all around us in soil and water, and on many people’s skin. Most people pick up an infection from contaminated water or surfaces, such as in healthcare facilities on equipment like ventilators and catheters. Inadequately disinfected hot tubs and swimming pools can cause mild P. aeruginosa infections in healthy people.

Symptoms of P. aeruginosa depend on the type of infection you have. Pneumonia may cause coughing and difficulty breathing; urinary tract infections cause pain and frequent urination; wound infections cause fluid leakage and inflammation; ear infections cause pain and impaired hearing.

Water-related P. aeruginosa infections can be easily treated with antibiotics. Treating severe hospital-associated P. aeruginosa infections can be difficult, however, because some bacterial strains show resistance to antibiotics. Antibiotics are usually administered for 7 to 14 days.

EDITORIAL SOURCES
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