PRINCETON, W.Va. (AP) — A county health administrator in West Virginia has resigned after his department mistakenly administered the wrong dosage of Moderna’s COVID-19 booster shot to about 200 people last month.

The Mercer County Health Department’s board accepted administrator Roger Topping’s resignation Tuesday night.

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During an Oct. 28 vaccine clinic, full doses of the Moderna booster were given out instead of the recommended half doses, news outlets reported.

Dr. Ayne Amjad, the state’s health officer, said the full dose is not harmful but could cause a stronger side effect in some people.

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Topping had said the department did not know half dosages should have been administered.

“We made a mistake,” Topping said. “We erred, and we are owning up to that. We are sorry it happened. But we thought we were doing what we were supposed to do. To my knowledge, we never received a memo that was directing us to use half of the full dose.”

Vaccine clinics operated by the Mercer County Health Department have been stopped temporarily.

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