Massachusetts General Hospital and the Boston Public Health Commission worked to test 750 residents who were not showing symptoms of the virus. The data shows that 9.9% tested positive for coronavirus antibodies, and 2.6% of asymptomatic people tested positive for COVID-19, meaning 1 in 38 residents could be spreading the virus without knowing they have it.
“The rate is lower than what we would have expected from earlier models of the virus spread. So the steps that we’ve been taking collectively and individually to slow the spread have certainly been working. We should be happy and proud of the city of that. Thank you to our folks who are part of this. I’m grateful for everyone who is doing what they need to do to keep themself, their family, and their city safe,” Walsh told reporters. “But the vast majority of Bostonians are still vulnerable to this infection.
The percentage of people with antibodies is probably somewhat higher because the study only looked at those who don’t have symptoms and who have not had a positive coronavirus test before.
Boston has reported over 11,000 coronavirus cases and more than 500 deaths. The study consisted of residents from East Boston, Roslindale and Dorchester.
Walsh said the results support his cautious approach to reopening Boston.
“The main value of this study shows us that a supermajority of the people of Boston have not contacted the coronavirus, and the concern as we think about reopening,” Walsh said. “It has to be very thoughtful, and it has to be very cautious.”
Learn more about the new test results here.
Earlier this week, universal testing on Boston’s homeless population revealed about one-third of those individuals had coronavirus.