PHILADELPHIA - The Pennsylvania Health Department has announced that second doses of the Moderna vaccine have been misused.As a result of the unprecedented mix-up, the second doses of the Moderna vaccine were instead used as first doses causing health officials to scramble in order to allocate those doses effectively.Health officials called it a "structural issue" that began in early January, but was not addressed until it compounded week-over-week. "As the Pennsylvania Health Department works to improve the complex processes necessary to get the COVID-19 vaccine from the manufacturers into the arms of Pennsylvanians as quickly as possible, we discovered some providers inadvertantly used the Moderna vaccine shipped to them, intended as.