What to do when a dog always licks its owner's feet

Excluding factors such as pica and anxiety disorders, the dog licking people may simply express feelings to the owner. If the owner does not like this method, then The owner can try to ignore it. When the dog licks the owner's feet, the owner immediately gets up and leaves the dog without saying anything and goes into another room. This method will teach the dog that its licking action will not attract the attention of the owner, and the owner will not be very happy. Once the dog stops licking its owner, you can interact with it.
Another method is that the owner can add a command when it licks, such as "kiss", and then reward it with some snacks. Soon the dog will learn to perform the licking behavior according to the command. And if the owner does not give instructions and stays away from the dog when it wants to lick, this will make it understand that it can only lick according to the command.

Does dog licking feet spread viruses or does it disinfect wounds?

If there are no wounds on the owner’s feet, the dog’s saliva will not bring any virus harm. Dog saliva mainly contains water, lysozyme and other substances. A very important function of lysozyme is sterilization, so dogs will heal faster by licking their own wounds. Although dog saliva is beneficial, because dogs often bite outside things with their mouths, the dog's mouth is likely to carry some bacteria and viruses. If the owner has wounds on his body, never let the dog lick himself.