In tomorrow’s episode
There are COVID-19 incidents in which a single person likely infected 80 percent or more of the people in the room in just a few hours. But, at other times, COVID-19 can be surprisingly much less contagious. Overdispersion and super-spreading of this virus are found in research across the globe. A growing number of studies estimate that a majority of infected people may not infect a single other person. A recent paper found that in Hong Kong, which had extensive testing and contact tracing, about 19 percent of cases were responsible for 80 percent of transmission, while 69 percent of cases did not infect another person. This finding is not rare: Multiple studies from the beginning have suggested that as few as 10 to 20 percent of infected people may be responsible for as much as 80 to 90 percent of transmission, and that many people barely transmit it.
{ The Atlantic | Continue reading | more on the k factor }
In late February, drug company Biogen held its annual conference in Boston. The United States had fewer than 20 known COVID-19 cases at the time. But one of the roughly 200 attendees must have carried the virus. It triggered a big outbreak. At least 97 people who attended the conference, or lived in a household with someone who did, tested positive. The Biogen meeting had become a superspreading event. Eventually, the virus spread from the meeting across Massachusetts and to other states. A recent study estimates it led to tens of thousands of cases in the Boston area alone. […]
A study from India published in Science last month concluded that 8% of infected people caused 60% of the secondary cases; 70% of people did not pass the virus on to anyone else.
{ Science | Continue reading }
A well-fitting N95 is the gold standard, but don’t worry if you can’t get your hands on one. When everyone wears a mask, the combined filtration efficiency increases. | NY Times | full story }
{ A room, a bar and a classroom: how the coronavirus is spread through the air | El Pais | full story }
to date, none of the vaccines being developed for the U.S. market has been proven to be effective in preventing Covid-19 disease.
and { Taiwan marks 200 days without domestic Covid-19 infection }
photo { Christopher Hainey }
