As New Scientist writer Stephanie Pain points out, if there's anything most people know about the Roman Empire, it's that Romans took a lot of baths.
Almost every Roman city had one or more thermae, bathhouses for taking hot baths, and one or more balnae, bathhouses for taking cold baths. Most Roman cities had multiple bathhouses. Everywhere Rome expanded its empire it made provisions for public baths, not just in what is now Italy, but in north Africa, in the Middle East, and throughout Europe as far north as the city of Bath in what is now England.
Bathhouses were something like hot tubs are now, only on a much grander scale. They came with restaurants, libraries, and stages for poetry performances. Taking a bath took hours, so many Romans made the baths the center of their social lives and the go-to place for professional advancement. Rome itself had 200 bathhouses, with hundreds of modern latrines and strict laws that sewage was to be removed from the city. In the public latrines, which could seat as many as 50 people at the same time, running water under the seats flushed waste into the sewer.
The Roman sewer system was far from perfect. There weren't any traps, so sewer gases could easily back up into the family's latrine (typically located in the kitchen). During floods, sewers could back up into houses and bathhouses. Moreover, raw sewage was used as fertilizer for the vegetables sold in the city market. Still, this system was a major improvement over the usual practice of the era, throwing human waste out the window into the street.
With all that bathing and even flush toilets, you would think that the Romans wouldn't have had as many parasites as the non-bathing barbarians, but that wasn't the case.
Piers Mitchell, a physician and a paleopathologist on the faculty at the University of Cambridge, developed a theory that Roman habits of cleanliness would have led to better health throughout its empire. Infectious diseases don't leave an archeological record, but parasites do. Intestinal worms have tough walls that can survive for thousands of years in fossilized feces. Fleas, ticks, and lice dry out and stay intact in fragments of cloth and combs. Chemicals produced by the amoebae that cause giardiasis and dysentery can persist in the dirt covering bodies long after the bodies themselves decay. If Imperial Rome's insistence on public cleanliness reduced the frequency of parasitic infection, then Roman archeological sites should show fewer remains of parasites.
But that isn't what Dr. Mitchell found.
Ancient remains in England showed that before the Roman invasion, people on the island suffered hookworms, roundworms, and dysentery. Mitchell expected there would be fewer of those parasites in remains of people after the Roman Empire came to Britain. There weren't.
Mitchell also found that fleas and lice were just as common in people who took regular baths as in those who didn't.
What could have gone wrong with the Roman efforts at personal hygiene?
For one thing, there aren't any records of how often the Romans changed the water in their baths. Roman historians record that the bath water was scummy from excrement and oils that Romans used to moisturize the skin after their baths that stayed on the skin until the next day. In lieu of a cleansing stream of water or toilet paper, Romans wipes themselves with a sponge, which was almost certainly shared with everyone else who used the toilet. By the second century CE Romans recognized that it wasn't a good idea for sick people and healthy people to bathe at the same time, so the Emperor Hadrian decreed that sick people should use the water first.
We don't do anything like that today, do we? Unfortunately we do.
Baths That Don't Leave You Cleaner
In the twenty-first century, it's relatively rare, at least in the developed world, for anyone to bathe in water that has fecal matter floating in it. We don't share toilet paper. We don't have to worry about developing gangrene if we bathe with an open wound.
However there are problems in personal hygiene that perpetuate other diseases even in the modern era. Here are some problem areas with easy fixes.
- Demodex infections. Everyone has at least a few of the tiny mites known as Demodex lodged on their facial skin. These almost-microscopic eight-legged creatures feed on excess skin oils and bacteria. In many (although not all) people who have acne rosacea, however, Demodex numbers build up and cause allergic reactions which are seen as acne-like breakouts. It's important (1) for people with acne rosacea to use fresh towels and wash cloths every day, so they do reinfect themselves with Demodex and (2) for other members of the household not to use the wash linens used by someone who has rosacea.
- Doggy do. The canine members of our families don't wipe up after they relieve themselves. For that reason, it's not a great idea for dogs to share bath water, swimming pool water, or hot tub water. Tapeworms in dogs can be transmitted to humans if water is swallowed, and hookworms in dogs can be transmitted to humans by contact.
- Swimmer's itch (known as "stinging water" in parts of Europe) is a parasitic infection of the skin with a form of schistosomiasis, which gets into water from bird droppings. Don't swim in lakes or rivers where birds congregate. Don't swim in a pool where there are large numbers of birds.
- Head lice infect about 20 percent of elementary school children. They are much more common in girls than in boys, due to the usual length of girls' hair. Lice can spread to anyone in the family who uses the same combs, the same towels, the same bed linens, or the same pillows. It's important not to share.
- Legionnaires' disease (legionella) is a bacterial infection that tends to accumulate in stagnant water. It's rare, although not unknown, for the infection to grow in hot tubs and shared physical therapy baths. If you share water for treating a sports injury, make sure that the therapist keeps the tub clean and uses appropriate disinfectants.
- Giardiasis, a particularly unpleasant long-term form of diarrhea also known as "purple burps," is spread by cysts from feces that find their way into water. It's a major hazard of bathing in "pristine" mountain streams (when you don't know who has bathed in them before you) and using any water in an area where people don't wash their hands after bowel movement. The only solution is not to drink or bathe in contaminated water.