County of Humboldt logoThe California State Epidemiologist recommended to local health offices last night that they pause administration of a single lot of COVID-19 vaccines, after a disproportionate number of severe adverse reactions was reported at a vaccination clinic in San Diego.

The lot, Moderna 041L20A, consists of 330,000 doses, a week’s worth of vaccines for the state, and as much as 90% of the doses the Humboldt County Public Health has on hand for vaccinations at its clinics this week.

Humboldt County Public Health officials have administered “hundreds” of doses from the lot, Health Officer Dr. Ian Hoffman said, with no severe or unusual reactions noted.

The lot number is written on the COVID-19 Vaccination Record Card given to individuals at the time of their vaccination. Any adverse reaction would occur immediately, usually within the first few minutes and certainly within 24 hours.

No vaccine from that lot has been administered by Public Health or its partners within the past 24 hours, and none from the lot will be administered until or unless the state determines the lot is safe to use.

Humboldt County Public Health has 3,500 doses from Moderna 041L20A in its freezer, 1,600 designated for first doses and 1,900 intended for second doses. Local providers have additional doses, but with “no replacement options at this time,” Dr. Hoffman said.

Public Health clinics scheduled for Wednesday, Thursday and Friday of this week may be impacted by the pause. People with appointments or invitations to be vaccinated will be contacted if appointments need to be canceled or rescheduled.

Dr. Hoffman also said it was possible the state might conclude the vaccine is safe and release the rest of the lot. “Obviously the goal for all of us is keeping people safe,” Dr. Hoffman said. “We’re going to pause as recommended until we hear more from the state, but without replacement doses, we’re balancing one set of risks against another.”

Investigation into the lot is led by the manufacturer, the Centers for Disease Control and Prevention and the Food and Drug Administration.

To see the news release from the California Department of Public Health, please follow this link:

The Joint Information Center will have additional information about this tomorrow.

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