Martha’s Vineyard towns are issuing indoor mask advisories as a public health precaution, as Covid cases spike upwards again due to the highly transmissible BA.2 coronavirus variant.

Dukes County is currently classified as high risk for Covid transmission, under Center for Disease Control guidelines.

Edgartown, Chilmark, Oak Bluffs and Tisbury all adopted mask advisories mid-week. West Tisbury expects to adopt the same advisory at its meeting next week, health agent Omar Johnson said. Information from Aquinnah was not immediately available.

The advisory urges vaccinations and caution when indoors.

“Please get vaccinated. Give careful thought to entering crowded indoor space if an alternate time might be less crowded,” the advisory says in part.

Vaccinations are available at the Martha’s Vineyard Hospital. The hospital opens up appointments for vaccines weekly, online on its website, starting at 4 p.m. on Fridays, according to spokeswoman Marissa Lefebvre. She said appointment slots fill up but more become available throughout the week on a rolling basis, due to cancellations and rescheduling.

“We always suggest people check throughout the week,” Ms. Lefebvre said.

During the recent surge in Covid cases, she said vaccination appointments have been filling up more quickly. She added that the hospital receives a steady supply of vaccines, but expanding appointments poses a challenge because of staffing shortages.

“It’s a little bit tough on that front, but we always try to expand when possible,” Ms. Lefebvre said.

She said PCR testing can be scheduled by calling the hospital at 508-684-4500.

Free test kits and N-95 masks are available for residents at all Island town halls.

Updated to include information from the hospital on vaccines and PCR testing.