DENVER (KDVR) — A health care provider alerted the Colorado Department of Public Health and Environment that a batch of expired COVID-19 vaccines had been administered to nearly 600 patients.

Now, the CDPHE recommends those who received Moderna vaccinations between September 2021 and May 2022 by Bloom Healthcare get revaccinated.

The health department said 558 people received one out-of-date dose of the Moderna vaccine and 27 received two doses.

CDPHE said there are no negative side effects from the invalid vaccine dose, but warned of its ineffectiveness and recommended getting revaccinated as soon as possible and to take caution.

Bloom Healthcare’s vaccination ability was paused by the health department but recently reinstated so it could administer proper doses to the patients affected by the expired batch. CDPHE said the majority of Bloom Healthcare’s vaccinations were not affected by the expired order.