I'm always hearing that you can't catch a particular infection from a toilet seat. Are there any diseases you CAN catch from a toilet seat? Or have we all been too paranoid about the porcelain god?

J.

Toilet seats are not common vectors (transmission channels) of infections. If you use the toilet seat in the usual manner, it is very unlikely that you will become infected with any disease-causing microbe. Specifically, there is no evidence that HIV (the virus that causes AIDS) or the viruses responsible for hepatitis B or C (chronic forms of liver inflammation) can be spread in this manner.

There are some organisms that conceivably could be acquired by contact with toilet seats, such as the strep (streptococcus) and staph (staphylococcus) bacteria that we routinely carry on our skin. It is possible that you could become colonized with a specific organism (become a carrier) after sharing a toilet seat with someone carrying that organism. But I think that the risk of such transmission is very small, and I personally do not worry too much about it.

Some infections are commonly spread in restrooms in areas other than the toilet. The classic source for bathroom infections is the reusable towel roller -- the device that holds a length of cloth toweling that you pull down for drying your hands. Other people end up using the same area to dry their hands, aiding in the potential spread of infections. Towel rollers can spread several different viruses and have been linked to outbreaks of conjunctivitis (also called pinkeye), inflammation of the membrane that lines the inner surface of the eyelids and the front of the eye. It is also possible that touching contaminated doorknobs and faucets can spread these sorts of infections, as well as the viruses that cause colds.

Bathrooms might seem the logical place for the spread of diseases that may be transmitted through fecal matter, particularly some viruses that cause gastrointestinal illnesses. However, the Norwalk viruses, the most common viral causes of gastroenteritis in adults, are much more often spread by contamination of food and water. When food handlers do not wash their hands after using the toilet and then return to their jobs, they may transmit such viruses through the food they prepare. It's possible, too, that if you touched a faucet or other surface soon after they did, transmission could occur. (Most bacteria that cause gastroenteritis require a large load of bacteria to cause infection, making it less likely they would be transmitted by touching surfaces.)

There is no way to know how frequently such infections are spread in bathrooms, but it probably is rare enough to justify continued use of public toilets. I do want to make clear that we should still use some common sense in public restrooms. But I would not become too concerned if there were a small lapse in the usual hygiene.