What is a Nosocomial Infection?

Medically Reviewed by Sanjay Ponkshe on February 27, 2024
4 min read

A nosocomial infection is an infection you get while you’re in the hospital for another reason. It's also called a hospital-acquired infection or a health-care associated infection.‌

Patients and healthcare professionals bring germs inside hospitals and pass them to each other. Sometimes, people carry these germs without feeling sick, which means they spread them to others without knowing. If you’re already in the hospital for surgery or another illness, your immune system might be too weak to fight off these germs.

Nosocomial infections happen when these germs make you sick within 48 hours after you’ve entered the hospital. You can get one at any healthcare facility. If these infections are not treated, they can cause more serious health issues.

There are several types of common nosocomial infections, including:

Bacterial infections. Bacteria are tiny living things that are too small to see. Most aren’t harmful, but some can cause serious illness. Bacteria are the most common cause of nosocomial infections. Common bacteria include E. coli and staph.

Fungal infections. Fungi are living things, like mushrooms, mold, and yeast. Some fungi can cause harmful contagious infections. The most common fungi that cause nosocomial infections are Candida (thrush) and Aspergillus.‌

Viral infections. Viruses are tiny germs that spread through your body by imitating your natural genetic code. They trick your body into making copies of them, just like the body makes copies of other cells. Viruses can cause severe sickness. 

Common nosocomial infections caused by viruses are influenza (flu) and respiratory synctial virus.

Nosocomial infections have different symptoms depending on their type. Some of the most common symptoms are:

  • Fever
  • Burning sensation while urinating
  • Cough
  • Extreme tiredness or weakness
  • Skin redness and soreness around a surgical or needle wound
  • Sweating
  • Muscle soreness
  • Nausea and vomiting 

Many things in a hospital environment can cause nosocomial infections.

Antibiotics. A doctor might prescribe antibiotics to prevent or get rid of an existing infection while you’re in the hospital. Many types of bacteria in your body are healthy and kill harmful bacteria. Because antibiotics kill both healthy and unhealthy bacteria in your body, taking them can raise your chances of nosocomial infection.‌

Urinary catheters. These are tubes inserted through your urethra into your bladder. It can be helpful during surgeries or other treatments when you can’t get up to use the bathroom for a long time. Leaving one inserted for too long can cause a bacterial urinary tract infection.

Breathing machines. Ventilators are machines that help you breathe by pushing air in and out of your lungs. Bacteria can live inside a ventilator and enter your body. This can cause pneumonia.

Central lines. A central line is a tube that connects to your neck, chest, arm, or groin to deliver medicine straight into your bloodstream. Germs can pass through the tube and cause dangerous bloodstream infections. These germs can live on medical gloves, on the skin where the tube is inserted, or the external end of the tube.

Not cleaning properly before surgery. Surgeries involve cutting into your skin. Harmful germs can enter your body if your skin or hair or the surgical tools aren’t completely clean before surgery.

Your doctor will run lab tests to see which infection you have. They may draw blood, take a sample from your lungs, or run another type of test. They'll also examine you and ask about your symptoms. 

Antibiotics. These are a common treatment for nosocomial infections. Medical tests help doctors figure out the specific bacteria causing your infection. Your doctor can then prescribe antibiotics that kill only these harmful bacteria and not the healthy kinds.

Rest. You’ll likely need to rest your body while you recover from an infection. Physical rest lets your immune system work as hard as it can to fight off illness.

Fluids. Water is important for your body while it fights an infection. Water helps keep your body cool if you have a fever and keeps your airways hydrated so you won't cough. Your doctor might tell you to drink lots of water. You may also need to get fluid injected into your body through an IV.

Doctors and other medical caregivers can prevent the spread of nosocomial infections by:

  • Fully disinfecting skin and equipment
  • Washing hands regularly
  • Wearing protective equipment like face masks and gloves
  • Regularly changing urinary catheters, and removing them as soon as possible
  • Removing hair near a surgical area
  • Prescribing antibiotics only when needed