Amazon Study of Workers’ Covid Is Faulted Over Lack of Key Data

Amazon.com Inc.’s analysis of Covid-19 infection rates among its workers has several flaws and falls short of assessing whether the world’s biggest online retailer did a good job protecting its workforce through the pandemic, according to infectious disease experts who track pandemics.

Last week, Amazon said that almost 20,000 of its U.S. workers had tested positive for the coronavirus during a six-and-a-half-month period. Amazon, one of only a few companies to provide such data, said the infection rate in its ranks was lower than that of most states, a finding it cited as evidence that investments in sanitation, ...