Dr. Paul Biddinger, who specializes in emergency preparedness at Massachusetts General Hospital and heads the governor’s COVID-19 vaccination advisory board, says a third of those eligible to be inoculated in Phase 1 haven’t received their shots yet even as Phase 2 begins today.

In an interview on The Codcast, Biddinger acknowledged the ups and downs of the vaccine rollout. “I think there’s obviously been some significant challenges with respect to getting vaccines out and into individuals as quickly as it’s arriving,” he said.

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