It's not that humidity stops the spread it just slows the spread. I told that to people on the blogs to add humidity to their homes as it slows the spread and of course there were several that took that to mean it kept it away. I was just warning them because if someone within the family got it it would slow down the spread to other family members, may even provide enough time from the notice of onset of the illness of one within the home to disinfect before it spreads to others. When you look at the countries along the equator the virus has been there for weeks it's just been slower to take off.