New Haven County is now being classified as an area of "high" COVID-19 transmission, according to the Centers for Disease Control and Prevention.
It is the first county in Connecticut to reach the CDC's "high" threshold. It first reached the "substantial" transmission threshold last Friday.
The remainder of the state remains in the "substantial" category.
The CDC's guidance, which recommends people wear masks indoors in areas where infection rates are classified as "substantial" or "high," is not a mandate and it leaves policy decisions up to the state and local level. At present, there is no mask mandate in the state, but the Connecticut Department of Health released a statement last week strongly recommending that people who live in, work in, or visit any of the affected counties follow the CDC guidance.
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Connecticut's daily COVID-19 positivity rate on Thursday was at 2.72%.