Is your water cooler being sanitized every 60-90 days?
If not, the inside of your water cooler may very well look like this. A scary thought, particularly for those returning to the office post-COVID whose water coolers may have been sitting unused for an extended period of time. The US Department of Energy recommends regular cleanings, with a bleach solution, with every other bottle change or every 6 weeks, whichever comes first, to reduce bacteria and biofilm buildup. Does your workplace have an appointed person overseeing the cleaning process?