How long do invisible germs survive on a visibly clean surface?

It does depend very much on the organism. Sone viruses and many fungi are resistant to environmental exposure. The survival of E. coli O157 was also investigated on stainless steel surfaces, where as air-dried deposits, it was shown to survive for periods in excess of 60 days. It was most stable at chill temperatures (4 degrees C) and viability was only partially reduced at 18 degrees C. In addition to stainless steel, the organism was shown to survive for extended periods on domestic (plastic) cutting boards, both at room and chill temperatures. Sanitizing agents, such as hypochlorites and a compound comprising both cationic and anionic-based active ingredients were found to be effective in killing various VTEC on stainless steel surfaces.

That depends on the bacteria.

The answer is probably not what you want to hear: Microbes can live on household surfaces for hundreds of years. The good news, however, is that most don't. Some well-known viruses, like HIV, live only a few seconds.

Microbes, of course, are everywhere. Each square centimeter of skin alone harbors about 100,000 bacteria. And a single sneeze can spray droplets infested with bacteria and viruses as far as 3 feet. The microbial life span depends on many factors, says Philip Tierno, director of microbiology and diagnostic immunology at the New York University School of Medicine. Because viruses must invade cells of a living host to reproduce, their life spans outside are generally shorter than that of bacteria, which reproduce on their own. Although viruses can survive outside a host on household surfaces, their ability to duplicate themselves is compromised-shortening the virus's life span.

Humidity also makes a difference; no bacteria or virus can live on dry surfaces with a humidity of less than 10 percent. Any sort of nutrients-food particles, skin cells, blood, mucus-helps microbes thrive, which is why your kitchen sponge is a breeding ground.

Bacteria called mesophiles, such as the tuberculosis-causing Mycobacterium tuberculosis, survive best at room temperature and are likely to thrive longer than cold-loving psychrophiles or heat-loving thermophiles. According to Tierno, at room temperature and normal humidity, Escherichia coli (E. coli), a bacteria found in ground beef that causes food poisoning, can live for a few hours to a day. The calicivirus, the culprit of the stomach flu, lives for days or weeks, while HIV dies nearly instantly upon exposure to sunlight. Other microbes form exoskeleton-like spores as a defense mechanism, like the bacteria Staphylococcus aureus, which is responsible for toxic shock syndrome, food poisoning, and wound infections. In this way, they can withstand temperature and humidity extremes. Tierno says this bacterial spore can survive for weeks on dry clothing using sloughed skin cells for food. The Bacillus anthracis, the anthrax bacteria, can also form spores and survive tens to hundreds of years.

Worried that your home is a hospitable habitat? Tierno says simple hand washing can greatly reduce your risk of picking up germs. Using a disinfectant on high-traffic surfaces-doorknobs, kitchen counters, and sinks-also helps eliminate unwanted household guests.

Many pathogens go into a dormant phase if placed in a harsh enviro, so they live months, maybe more. Fungi can live yrs dormant. You'r right abt touching those surfaces, use the cuff of your sleve or something so you dont touch them w/ your skin. At home, wash down surfaces w/ a dilute bleach solution. Wash food containers from super market and sanitize eggs w/ the dilute bleach.

the old die off in 36 hours. the others just reproduce from the the original germs, they go on forever, unless you kill them off with dissinfectant.

Spray Lysol and it will get rid of 99.999999999999 % of all germs !

well, as long as you feed them and take care to sleep a lot, they will be your friends for a long, long time!

they go dormant until water and nutrients arrive.