How long do bacteria live on surfaces?

Many questions have arisen along with the awareness of the cause of disease and infection. One of the most important questions, particularly in safeguarding your family's health, is how long do bacteria and other microbes live on any given surface? The answer may surprise you.


Bacteria are the main cause of illness and food-based illness in most people. That's because there are literally trillions of bacteria on any given surface. Of course, how long they live depends upon the surface itself. Different surfaces can allow the bacteria to live from just a few hours to several days, or even months.


The least favourable type of surface for bacteria to live on is a hard, nonporous surface; a countertop, tile floor, or glass surface is a poor surface for bacteria. Under unaltered conditions, a bacteria colony will last a few hours on this type of surface, and even less if an attempt at sanitising is made. Chemical products used around the house, particularly ones with bleach, kill bacteria even faster. So does sunlight; the ultra violet rays of sunlight kill bacteria almost instantly because the single-cell organisms have no defence against harmful radiation.

Time Frame

Soft, wet surfaces (preferably with plenty of food) are perfect for bacteria. Cloth, sponges and carpets that have become wet are excellent living places for bacteria because it protects them from exposure to the environment; dry air or sunlight, for example. These surfaces should be cleaned thoroughly, especially if they begin to smell "funny" or "sour." Those smells are a certain indication that a surface is crawling with bacteria because those smells are the gasses that bacteria give off as part of their living, breeding and eating. Washing a sponge or cloth in bleached water, or using a steam cleaner on a softer surface, will kill the bacteria fairly quickly. Otherwise, bacteria could live on those surfaces for days (in the case of a sponge) or weeks (in the case of clothes) or even months (in the case of carpet).


Money is another surface upon which bacteria can live for quite some time. Paper money is often the worst, but even upon coins, bacteria can live for several hours, at least. Most money is touched by hundreds, or thousands, of people, comes in contact with a variety of surfaces, and is porous, allowing bacteria to migrate deep inside the fibres to avoid environmental hazards. Money can host bacteria for several weeks at a time, and if used frequently (like 60p, £3 and £13 bills) can be reinfected over and over again.


Above and beyond all surfaces that bacteria like to live on, human hands are perhaps their favourite. We use hands to touch everything from the dog's faeces to the fork on our plate. We shake hands, touch money, and cough or sneeze into our hands. Hundreds of varieties of bacteria, ranging from mostly harmless to highly infectious, reside on people's hands all the time. The most important prevention to the spread of bacteria is to wash your hands. Any soap with warm water, a healthy lather, and vigorous rubbing will suffice; it doesn't help to have an "antibacterial soap" if you don't wash thoroughly enough. In fact, the misuse of antibacterial soap may make these microbes stronger as a result, negating the effects of anti bacterial soap altogether. In fact, the American Medical Association and the Food and Drug Administration both questioned the use of antibacterial soap's effectiveness against the spread of infection and theorised that such misuse would make infection more likely in the future.