The warm, moist environment of the hot tub is relaxing but can also be inviting to certain bacteria, viruses, and fungi. Bacteria such as mycobacteria, E. coli, and pseudomonas aeruginosa can live in the slime found on wet surfaces and in pipes. They can all cause infection.

"Hot tub folliculitis," is caused by bacteria, such as pseudomonas, that live in the hot tub. Infection of the hair follicles results in red, itchy bumps or pustules. These may go away on their own without treatment or a doctor may need to write a prescription for medicine.

The bubbling water creates aerosols that can lead to lung infections by mycobacteria or other organisms. Direct contact with infected people in the hot tub can lead to herpes and fungal or bacterial infections.

It is important to drain and clean the tub after use and to maintain proper chlorine and pH levels. Pipes and filters should be disinfected. Everyone should shower before entering the hot tub.

If you have a rash, respiratory problems, or an infection, see a doctor for treatment.