5 most common HCAIs

Surgical site infection

A surgical site is the cut (incision) in the skin made by a surgeon to carry out surgery. Where the cut is made and its size depends on the type of surgery. A surgical site infection can occur when bacteria (germs) enter the cut made by the surgeon. This results in symptoms such as redness, swelling or pain at the site of the cut as the body tries to fight the infection.

Surgical site infections can be superficial (affecting the skin only) or more severe (affecting the tissues/muscles under the skin). Surgical site infections cannot always be prevented. The likelihood of an infection depends on a number of factors related to both the patient's general health at the time of surgery and the type and duration of surgery carried out.


Pneumonia is an infection of the lungs that can cause mild to severe illness. Symptoms include cough, shortness of breath and fever.

The majority of patients who are treated for pneumonia in hospital are admitted with the infection (having acquired pneumonia in the community).

However, hospital-acquired pneumonia can occur especially in intensive care patients who require assistance with breathing (on a life support machine or ventilator). Pneumonia can be a severe infection and can sometimes be fatal.

Urinary tract infection

The urinary tract includes the kidneys (which filter the blood to produce urine), the ureters (the tubes that carry urine from the kidneys to the bladder), the bladder (which stores urine), and the urethra (the tube that carries urine from the bladder to the outside). Urinary tract infections occur when germs get into the urethra and travel up into the bladder.

Symptoms of urinary tract infection can include; passing urine more frequently than usual, pain passing urine, fever and chills. Patients who have a catheter (tube) inserted into the bladder to drain urine are more likely to develop a urinary tract infection.

Bloodstream infection

A bloodstream infection can occur when germs enter the blood. Symptoms include fever, chills, general weakness, nausea and vomiting. Patients with a catheter (drip) placed into a vein are more likely to get a bloodstream infection. These are very serious infections and can be fatal.


Gastroenteritis is inflammation of the bowel caused by an infection. Symptoms include diarrhoea, vomiting and tummy cramps. Gastroenteritis is commonly acquired in the community and those affected (especially the elderly and children) may be admitted to hospital due to dehydration.

Hospital-acquired gastroenteritis is most commonly caused by Clostridium difficile and the winter vomiting bug (Norovirus). Norovirus is usually a mild illness. However, for a small number of patients Clostridium difficile can be a severe infection and, in rare cases, can be fatal.

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