COVID-19 may be most contagious one to two days before symptoms appear: Science News

hospital by Silas Camargo Silao via pixabay.com

Here’s a link to the article.  It states that 44% of cases may be transmitted before symptoms appear; this was found in a series in which one patient was definitely known to be infected by another.  The study quoted was performed in China in the first two weeks of February.  Here’s a quote from the article:

Analyzing 77 infector-infectee pairs allowed researchers to calculate when people are most contagious. The team estimates that contagiousness starts 2.3 days before symptoms begin and peaks 0.7 days before symptoms start.

Based on the information from the aircraft carrier docked in Guam, 60% of cases may be free of symptoms; even when there are symptoms, the patient will be spreading the infection before the symptoms even start.  This is the most insidious known virus, clearly highly evolved to spread through-out the human population.