Soap and warm water have long been said to prevent the spread of infections, but is warm or hot water really more effective than cold? ...There is something seriously wrong with this story. Removing germs is not the only purpose to washing hands.
“Temperature of water used for hand washing should not be guided by antibacterial effects but comfort,” they wrote, ...
Hot water for hand washing has not been proved to remove germs better than cold water.
I wash my hands to get rid of dirt, oils, and germs. I always thought that warm water was more effective at getting rid of dirt, not germs. This article does not even address whether the warm water is better for cleaning dirt, and yet it recommends cold water as being just as good.
This is a problem with a lot of science-based recommendations. Someone will quote a study, but the study may have only looked at one aspect of the matter.