DETROIT – Until now the Centers for Disease Control and Prevention (CDC) defined “close contact” with COVID-19 as spending 15 consecutive minutes within 6 feet of someone who is positive.
Researchers have discovered much shorter exposures can also spread the virus, especially if those exposures are repeated. That discovery has implications for schools, workplaces and all sorts of gatherings.
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The update comes after new research shows that cumulative time around infected people, if it is multiple, but brief encounters is just as important.
The CDC study examined the case of a male Vermont correctional officer who had multiple brief interactions with six incarcerated people who were all asymptomatic and awaiting the results of their COVID-19 tests. Those tests came back positive.
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Contact tracing was conducted, but health officials said the officer did not meet definition of a close contact since he didn’t spend 15 consecutive minutes with an infected person. The officer continued to work, but eventually developed symptoms and tested positive two weeks later.
A review of surveillance video showed the officer had nearly 24 brief encounters that lasted roughly a minute each for an estimate of 17 total minutes of cumulative exposure.
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The report said the officer wore a microfiber cloth mask, gown and eye protection during all interactions. The prisoners wore microfiber cloth masks during most of the interactions that occurred outside a cell.
The CDC has redefined what is considered to be a close contact of a COVID-19 case to now include someone who has been within 6 feet of an infected individual for a total of at least 15 minutes a day.
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