Bacteria found in restaurant or cafeteria soda fountain drinks can be a health risk to people with compromised immune systems, including people living with HIV, according to research from Hollins University in Roanoke, Virginia, and reported on by CBS News.

In the study, researchers tested 30 soda fountains and found many of the beverages to be contaminated with bacteria. Coliform, or fecal, bacteria was found in 48 percent of the tested drinks, while potentially deadly E. coli bacteria was found in 11 percent of them.
Poorly cleaned fountain drink machines and employees or customers who do not wash their hands properly before touching the machine can cause contamination, explained Alanna Levine, MD, a primary care physician. But the primary source of the contamination, she said, was likely the machines' water lines.

“Any time any water or liquid sits somewhere, it's just a breeding ground for bacteria,” Levine explained.