Delta virus, the more dreadful variant from original COVID, is now rapidly spreading around the world.  Report says it is more contagious among humans, even through air, not only by saliva spitted.

These day my son came home to see us.  He has been vaccinated with two shots of Pfizers already, still he is very alert to the new situation.  The other night, he had itching throat, nasal congestion, and light cough, so we gave him several pills of Tylenol and urged him have a good-night sleep earlier.  The next day, he said the symptoms alleviated and he felt a little bit better, yet he wanted to take a NAT.  But the NAT stations in nearby areas had been fully booked.  So he went to a pharmacy in neighborhood to purchase a set of DIY test kit.  He did the test by himself and the result indicated "negative".