At least 3,900 people may have received an incorrect dosage of COVID-19 vaccine last fall in Northern California, a health care provider said Monday.

In a statement to Nexstar, Kaiser Permanente said those who received Pfizer COVID-19 vaccinations at the Kaiser Permanente Walnut Creek Medical Center between October 25 and December 10 last year "may have received a slightly lower than recommended dose of vaccine.

Incorrect COVID Vaccine Dosage Given in California 

Kaiser Permanente noted that the affected individuals in California may have received 0.01 to 0.04 mL less than the recommended 0.30 mL dose.

Officials said they consulted infectious disease and vaccine science specialists and guidelines from the Centers for Disease Control and Prevention (CDC) after they became aware of the problem.

The statement reads that all experts concluded that the difference between the prescribed dose is not likely to decrease their protection against COVID-19.

However, Kaiser Permanente said they are offering to provide a repeat dose of Pfizer vaccine to affected individuals who choose to receive it in "special hours and locations."

Some staff misunderstanding instructions and drawing slightly less than the appropriate dose reportedly caused the problem.

Kaiser Permanente said staff had been retrained, and they are "continuously monitoring" to ensure that this won't happen again.

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14 Kids in Northern California Receive Wrong COVID Vaccine Dose

Last November, a healthcare provider with Sutter Health medical centers confirmed that several children in Northern California received an incorrect dose of the COVID-19 vaccine. 

"As soon as we learned of this, we contacted the parents and advised them of CDC guidance in this situation," said Dr. Jimmy Hu, Chair of the Sutter Health COVID-19 Vaccine Task Force.

Hu noted that 14 patients in Antioch pediatric vaccine clinic received COVID vaccines with an incorrect amount of diluent.

According to the CDC, patients who receive a wrong diluent volume may experience more arm soreness, fatigue, headache, or a fever.

Sutter Health refused to clarify whether the kids were given extra diluent or less diluent. But Dr. Peter Chin-Hong, an infectious disease expert at UCSF, said the children affected by this mistake should be just fine.

A diluent is a normal, preservative-free saline (0.9 percent sodium chloride) that is mixed with the vaccine. According to the CDC's Pfizer vaccine preparation guide, it comes in a separate vial from the vaccine, and medical officers are required to prepare each dose with a new vial of vaccine and a new vial of diluent every time.

CDC said the vaccine for children aged 5 to 11 should contain 1.3 mL of diluent. The diluent dose for this age group has an orange cap to distinguish it from the diluents for individuals aged 12 and up.

CDC noted that if a kid was given less diluent than recommended, the dose should not be repeated, but the child's parents or guardians should be informed of any potential side effects.

If the kid was given additional diluent, the CDC said the vaccination administrator should immediately repeat the dose.

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This article is owned by Latin Post.

Written by: Jess Smith

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