How long do bacteria and viruses live outside the body?

It depends on the type of bacteria or virus and what kind of surface they are on. Most bacteria, viruses and fungi that cause diseases need moisture to survive so the moisture in the air and in surfaces can also affect how long they live outside the body.

Cold viruses

Cold viruses have been shown to survive on indoor surfaces for more than seven days. In general, viruses survive for longer on non-porous (water resistant) surfaces, such as stainless steel and plastics, than porous surfaces, such as fabrics and tissues. Although cold viruses have been shown to survive on surfaces for several days, their ability to cause an infection starts to decrease after 24 hours.

Most cold causing viruses survive on hands for a much shorter time. Some only last for a few minutes but 40% of rhinoviruses, a common cold-causing virus, are still infectious on hands after one hour.

Respiratory syncytial virus (RSV), another cold-like virus that sometimes causes serious illness in children, can survive on countertops for up to six hours, on cloth and paper for 30-45 minutes and on skin for up to 20 minutes.

Flu viruses

Flu viruses capable of being transferred to hands and causing an infection can survive on hard surfaces for 24 hours. Infectious flu viruses can survive on tissues for only 15 minutes.

Like cold viruses, infectious flu viruses survive for much shorter periods on the hands. After five minutes the amount of flu virus on hands falls to low levels.

Flu viruses can also survive as droplets in the air for several hours and low temperatures increase their survival in the air.

Parainfluenza virus, which causes croup in children, can survive for up to 10 hours on hard surfaces and up to four hours on soft surfaces.

Stomach bugs

There are many germs that can cause a stomach bug. They include bacteria such as E coli, salmonella, Clostridium difficile (C difficile) and campylobacter, and viruses such as norovirus and rotavirus.

Salmonella and campylobacter survive for short periods of around 1-4 hours on hard surfaces or fabrics. Norovirus and C difficile, however, can survive for much longer. In one study, C difficile was shown to survive for five months. Norovirus can survive for days or weeks on hard surfaces.

When someone with norovirus vomits, the virus is distributed in small droplets in the air. These droplets can settle on surfaces, causing the virus to spread, so it’s important to clean surfaces thoroughly if someone in your home has been infected with norovirus.

To help prevent the spread of stomach bugs wash your hands thoroughly and regularly, particularly after going to the toilet, and practise good food hygiene.

MRSA

The staphylococcus aureus bacteria that cause MRSA infections can survive for days to weeks on surfaces. MRSA bacteria can live on surfaces for longer than some other bacteria and viruses because they survive better without moisture. Generally, MRSA bacteria survive for longer on hard surfaces than on soft surfaces.

Herpes

Herpes viruses from cold sores around the mouth can survive for four hours on plastic, three hours on cloth and two hours on the skin. If you have a cold sore, try not to touch it. If you do touch it, for example to apply cold sore cream, always wash your hands immediately afterwards.

Preventing the spread of infection

It is not always possible to avoid catching an illness, but there are ways to reduce your risk and to prevent infections spreading to others:

  • Wash your hands regularly, particularly after going to the toilet, before handling food and after coughing, sneezing or blowing your nose.
  • Keep your home clean and hygienic, particularly if a member of your family is unwell. Read more in How to prevent germs from spreading.
  • Wash fabrics that may be contaminated with bacteria or viruses at 60ºC (140ºF) and with a bleach-based laundry product. Read more about keeping clothes clean in Can clothes and towels spread germs?

Read the answers to more lifestyle questions.

Further information

Page last reviewed: 09/10/2013

Next review due: 08/10/2015