Fairfield, Windham and Tolland counties have all reached the Centers for Disease Control and Prevention's recommended threshold for universal indoor masking, according to the latest data from the agency's COVID Data Tracker.
Hartford, New Haven and New London counties reached that level earlier in the week, meaning six of the state's eight counties are all seeing significant COVID-19 transmission.
"It’s concerning but not a surprise. This delta variant is very contagious and we have seen a steady increase in our case numbers," Acting Department of Public Health Commissioner Deidre Gifford said of the latest CDC data.
The Connecticut Department of Public Health said Thursday that it "strongly recommends" that anyone over the age of 2 wear a mask in public indoor spaces, regardless of vaccination status, in line with the CDC guidance.
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The CDC recommends universal masking in indoor spaces for regions that are experiencing "substantial" or "high" transmission levels of COVID-19.
The CDC guidance is not a mandate and it leaves policy decisions up to the state and local level. At present in Connecticut, an executive order remains in effect that requires those who are not fully vaccinated against COVID-19 wear a face mask in public indoor spaces where they cannot social distance, according to DPH.
State officials are urging residents to get a COVID-19 vaccine as the delta variant continues to spread. Connecticut has one of the highest vaccination rates in the country, with about 2.3 million residents having received at least one dose.
DPH says breakthrough cases of the vaccine are very rare, and COVID-19 related deaths in people who had the vaccine amount to less than .01% of reported deaths in the state since the pandemic began. State officials say current data shows that you are 17 times more likely to get COVID-19 if you are unvaccinated.
The state's positivity rate came in at 2.72% Friday, up from 2.35% the day before. There were 18,025 new tests reported, with 491 new cases. There are 116 people hospitalized with the virus, a net increase of four from the day before.
The state is reporting COVID-19 related deaths once a week, on Thursday. To date there are 8,293 deaths reported in Connecticut, an increase of seven from last week.