Can You Really Get Gonorrhea from a Toilet Seat?

E. coli, giardiasis, and shigellosis are diseases people actually get from public toilets (although not very often). Sexually transmitted diseases are what people fear they can get from toilet seats. Let's take a look at the transmissibility of these microorganisms.

• HIV is not transmitted in public toilets, unless it is by sex in public toilets. The virus does not survive outside the human body, even in urine or feces, long enough to be transmitted to another person. Simply swallowing the virus would not be enough to cause an infection in most cases.
• Gonorrhea can be transmitted through contact with vaginal secretions, semen, mucus, and skin secretions. It is unlikely to be transmitted by saliva unless the saliva is vigorously inserted into another person. The bacteria that cause gonorrhea are detectable in urine, but you can't get gonorrhea by sitting in that urine. As one doctor puts it, "The only way you are going to get gonorrhea on a toilet seat is by having sex with an infected person while on that toilet seat."

• Syphilis in very, very, very rare instances could be transmitted by secretions of a highly infectious person (someone who has an unusually high concentration of the bacteria in his or her bloodstream) left on a toilet seat then coming in contact with an open cut in the backside or genitals of the next user. There are many places, by the way, where syphilis is essentially unknown, that is, almost no one has it.
• HPV (human papillomavirus) usually requires skin-to-skin contact. The virus will not survive on a toilet seat. 
• Herpes, in theory, could be transmitted on a toilet seat in the same way as syphilis. There is only report of this in the English-language medical literature, and this occurred on a home toilet, not a public toilet.

There, are however, certain germs that are transmitted in the spray of water that goes up when a toilet is flushed, even if the water appeared to be clean. These include:

• Norovirus. This virus causes up to 90 percent of all cases of viral "stomach flu." People continue to spread the virus long after symptoms subside. The virus can be spread in an aerosol. If you happen to come in contact with the toilet spray, you can get a norovirus infection. 
• Tuberculosis. We usually think of tuberculosis as a lung infection, but it can also be an intestinal infection. TB bacteria are very easily mixed with water droplets in toilet spray. It is possible to catch TB in a toilet, although it would usually take multiple exposures.
• H1N1 flu can be transmitted in toilet spray after the toilet is used to collect vomit. It is not easily transmissible through feces.
• Hard to manage bacteria infections such as Clostridium difficile, vancomycin-resistant Enterococcus, and methicillin-resistantStaphylococcus aureus (MRSA) tend to persist on toilet seats even after cleaning. However, you are not likely to encounter them outside of hospitals and care facilities.

READ Gonorrhea: A Superbug Becoming Increasingly Resistant to Antiobiotics

The bottom line is that it is not impossible to catch an infection in a toilet. It's just unlikely. And there are things you can do to lower your risk.

• If the toilet has a lid, close it before you flush.
• Don't face the toilet when you flush.
• Wash your hands both before and after you use the toilet. You don't want to transmit an infection from somewhere else (especially staph or step infections) to your privates.
• Avoid toilets in airplanes as much as possible. They are especially likely to harbor norovirus.
• Use the protective paper sheet or spray the toilet seat with disinfectant before using. 
• Beware toilets that are seldom used. They can harbor a biofilm, a naturally occurring sheet, of infectious bacteria. Some species of bacteria, such as Shigella, E coli, C difficile, severe acute respiratory syndrome (SARS) coronavirus, and norovirus can survive for three months or even longer.