CONCORD, N.H. (CBS) — New Hampshire is promoting COVID vaccine booster shots this weekend with more than a dozen clinics around the state.

The “booster blitz” initiative had 15 communities hosting sites on Saturday that offered booster shots only.

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It was required for patients to have already gotten their preliminary vaccine shots (two of either the Pfizer or Moderna COVID vaccine or the single shot Johnson & Johnson version).

Gov. Chris Sununu was among those getting his booster on Saturday. He later tweeted a video message to the people of New Hampshire with his vaccine card in his hand:

“This is Gov. Sununu at the ‘booster blitz.’ Just got my booster shot. Going incredibly well in there. 12,000 boosters are going to go out today, which is really just great. Big thank you to all the first responders, firefighters and nurses who are making this possible. It’s already such a huge success this morning. There’s no doubts we’re going to have a plan to do it yet again.”

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Sununu says additional booster clinics will be added as needed.

The National Guard was recently called in to help overwhelmed hospitals in New Hampshire. Hospitalizations are also at their highest levels since the start of the pandemic.

On Thursday, the state reported that there were over 10,000 current cases of coronavirus in New Hampshire for the first time ever.

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About 55% of New Hampshire residents are vaccinated, which is the lowest vaccination rate in New England. Staff