The city and Massachusetts General Hospital today released results from the recent random Covid-19 testing in East Boston, Roslindale and part of Dorchester: 9.9% of the people tested positive for Covid-19 antibodies - and that roughly 1 in 40 people with no symptoms were currently infected with the virus and so potentially infectious themselves.
Hospital and city public-health staffers tested 750 people in the neighborhoods for both antibodies, through a finger-prick blood test, and for active infection, through a nasal swab. A positive result on the first test means the person was exposed to enough of the virus to develop antibodies to it, but is likely no longer infectious; a positive result on the second test indicates the person's body is currently battling an infection. People who had previously tested positive for infection or who were showing active symptoms were excluded from the tests.
In announcing the results, Mayor Walsh said:
We can draw two preliminary conclusions from the results of this study. First, that the actions we took early on in this pandemic made a real difference in slowing the spread and, second, that the majority of our population still have not been exposed to the virus. This underscores what we already know, that we have to move cautiously and stay focused on what got us this far. This can be done by a gradual, phased-in approach to reopening that includes clear health criteria and safety guidelines for each industry and depends on testing and hospital metrics reaching certain benchmarks, and continuing to move in the right direction.
The city released some specific details:
- East Boston: 1.1% tested positive for COVID-19, 13.3% tested positive for antibodies
- Roslindale: 2.2% tested positive for COVID-19, 7.6% tested positive for antibodies
- 02121 in Dorchester: 2.7% tested positive for COVID-19, 6.3% tested positive for antibodies
- 02125 in Dorchester: 4.6% tested positive for COVID-19, 12.1% tested positive for antibodies
The median age of people getting a test was 42.4; 61.6% were female, the rest male. In terms of neighborhoods: 36.8% are from Roslindale, 25.1% are from East Boston, 23.2% are from 02125 in Dorchester and 14.9% are from 02121 in Dorchester. Also: 62% are white, 18.7% are Black/African-American, 12% are Latinx/Hispanic, 2.3% are Asian/Pacific Islander and .13% are American Indian/Alaska Native. 1.6% preferred not to say and 1.6% are unknown. There were no significant differences in COVID-19 or antibody rates by race or ethnicity in this sample, the city says.
Mass General President Peter Slavin added:
The testing that the teams from Boston and the MGH conducted shows that approximately 90 percent of the city's residents have not yet been exposed to the virus. We also know that COVID-19 will be with us for a while. It is vital therefore that we be thoughtful and careful about reopening, and that we continue to take actions - wearing masks, physical distancing, working from home when possible, limiting gatherings - that can prevent another surge of the disease.
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