Technology has changed since the Jack in the Box outbreak, when it was impossible to test for E. coli.
But estimating R0 in the early stages of an outbreak, when it is most useful, is hugely difficult.
The figures are edging closer to those of the 2017 outbreak, when 1 million cases were reported.
And many, especially at the beginning of the outbreak when the numbers were highest, were not tested, Dr. Osterholm said.
"Last year we were only just beginning to recover from the foot-and-mouth outbreak when Sept. 11 happened, and one thing segued into another.
This trust proved crucial during the Ebola outbreak, when traditional healers were persuaded to refer patients to treatment centres and were taught how to stop it spreading.
Pooley had been working in a hospital in the city of Kenema, the main centre of the Ebola outbreak, when he tested positive.
A second near-crisis was averted in the early, chaos-strewn days of the outbreak, when two women from the Wharf escaped from a treatment centre.
Masks are for when you can't avoid a closed space during a serious outbreak — when, say, you need to travel by a crowded bus or plane or subway.
Early in the outbreak, when fear was rampant, seven million children in and around the capital were kept home from school.
Patriots fan Don Crisman, who has never missed a Super Bowl, told the Guardian that he has been in town since Monday but only learned about the measles outbreak when he spoke to his wife by phone on Thursday morning.
