By CBSBoston.com Staff

BOSTON (CBS) – The Centers for Disease Control and Prevention has released an updated map showing high levels of COVID-19 transmission across the country.

There are now nine counties in Massachusetts where it’s recommended that people wear masks indoors, even if you’re fully vaccinated, because transmission rates of coronavirus are high or substantial.

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(WBZ-TV Graphic)

Barnstable and Nantucket counties are considered high risk.

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Middlesex, Suffolk, Bristol, Plymouth, Essex, Worcester and Hampden counties are now all considered substantial risk.

The CDC’s transmission data is a combination of new cases by population and positivity rate.

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You can see the latest CDC map here.

CBSBoston.com Staff