Pseudomonas aeruginosa Frequently Asked Questions

What is "pseudomonas"?
Pseudomonas is a bacteria ("germ") that belongs to a family of bacteria known as the "pseudomonads". Pseudomonads are very common bacteria that are usually found in water, soil and on plants. Most pseudomonads are harmless to humans, but some, such as Pseudomonas aeruginosa, can occasionally cause infections in humans.

What sorts of infections are caused by pseudomonas?
Most human infections caused by pseudomonas are not severe and easily treated. These include:

  • Folliculitis (a type of skin infection that typically occurs after swimming in contaminated water)
  • Dermatitis (a type of skin rash) after using a improperly cleaned spa pool (also known as "hot tub rash")
  • Otitis externa (infection of the outer ear) after exposure to contaminated water

Other types of pseudomonas are much less common and usually only occur in people with very weakened immune systems, such as premature babies, people being treated in intensive care units and people on cancer chemotherapy. These more serious pseudomonas infections include:

  • Wound infection (particularly in severe burn wounds)
  • Pneumonia and lung infections (particularly in people treated in intensive care units and in people with cystic fibrosis)
  • Bloodstream infection ("blood poisoning” or “septicaemia") (particularly in people treated in intensive care units, or on cancer chemotherapy)
  • Kidney infections (particularly in people who have had a urinary catheter in place for a long time)

Most serious infections caused by pseudomonas only occur in people who are already suffering from another serious illness.

Pseudomonas can cause healthcare-associated infections in hospitals, and can sometimes be spread between patients. Pseudomonas outbreaks are rare, but can occur in hospitals. When outbreaks do occur they are often linked to a contaminated source of water or other liquid.

How are pseudomonas infections diagnosed?
Pseudomonas infections are diagnosed by taking a sample from the body site where the infection is found and looking for the presence of pseudomonas in a laboratory.

How are pseudomonas infections treated?
Minor skin infections or rashes caused by pseudomonas can often be treated with topical therapies (e.g. an antiseptic cream that is spread onto the site of the infection). Other pseudomonas infections are treated with antibiotics. Some pseudomonas infections can be treated with antibiotics that are given by mouth. For severe pseudomonas infections, such as bloodstream infection or pneumonia, antibiotics usually have to be given intravenously (by a "drip").

How can I protect myself from pseudomonas infections?
Pseudomonas infections are uncommon, but you can reduce the risk even further by taking the following precautions:

  • Avoid swimming in polluted water
  • Always dry your ears really well after swimming, showering or using a hot tub/spa pool
  • Always shower with soap and water after swimming or using a hot tub/spa pool
  • Wash your hands before preparing food, before eating and after using the toilet
  • Wash your hands (or decontaminate them with alcohol-based hand gel) before and after caring for anyone with an illness
  • Always follow your doctor’s advice if you are being treated for an infection

If you have a medical condition that is associated with an increased risk of pseudomonas infection (such as cystic fibrosis or if you are on therapy for cancer), ask your doctor about specific steps you should take to avoid pseudomonas infection.

Where can I find more information on pseudomonas infections?
The Public Health Agency, Northern Ireland has produced leaflets for parents/carers.

More information and guidance are available from the following websites:

Updated: 26 January 2012