The number of new Covid-19 cases on Martha’s Vineyard for the week ending Saturday, Oct. 23 showed a decline after three weeks of gradually increasing numbers.

There were 20 confirmed cases of the coronavirus for the week, down from 26 the previous week, according to a weekly report released Monday by the Island boards of health.

In a subsequent email, the boards of health said five more cases had been confirmed since the report, one on Sunday and four on Monday.

Twelve of the 20 cases were in vaccinated individuals, six were unvaccinated and two were unknown. Three of the cases were in children under 11. Currently, children between 5 and 11 are not eligible for vaccination, but the Federal Drug Administration’s vaccine advisory panel was scheduled to meet Tuesday to reconsider that policy.

On Friday, the Martha’s Vineyard Hospital announced it was releasing 528 new appointments for Pfizer vaccine booster shots and that more appointments would be released in a week.

Appointments will be only given to individuals who received their second Pfizer dose at least six months and are 65 years of age or older, immune compromised or have an eligible underlying medical condition, the hospital.

In an email, a spokeswoman for the hospital said booster shots of the Moderna vaccine are not yet available, nor is the hospital allowing people to mix vaccine brands at this time.

New cases of Covid-19 on the Island saw their lowest number since July in the week ending Sept. 25, when eight new cases were recorded. Over the next three weeks, cases rose slowly, with 11, 25 and 26 recorded for each week.