CHARLOTTE (QUEEN CITY NEWS) – A Charlotte father said his son got a double dose of the COVID-19 vaccine booster earlier this week.

“Our son, who is 6 years old, received a double dose of the booster, and at that point, our brains kind of went, ‘Holy crap, what does this mean?’ Because it’s a scary unknown,” said Ryan Shell of the phone call his wife received from the clinic which administered the shot.

The Food and Drug Administration said children aged 5 to 11 should get a 10 microgram dose. Shell said his son received a 20 microgram dose, which is normally for adults.

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Incidents like this are rare, but not unusual. There are reports of similar occurrences in other parts of the United States, where groups of children unintentionally received a double dose of the COVID-19 vaccine.

In adults, the vaccine can cause a sore arm, fatigue, headaches, and fever.  Experts said an adult dose of the vaccine on a child can lead to more pronounced or prolonged side effects.

Shell still believes his son should have gotten the vaccine, but said, “now looking back, it’s important for parents to understand what is the correct dosage.”

Shell said his son received the vaccine at the Teen Health Connection, which is a part of Atrium Health. In a statement, a media relations person said:

“Atrium Health Levine Children’s encourages families with eligible children to receive the COVID-19 vaccine series, including the booster, as the best way to keep children and their families safe. On the unlikely occasion in which a child receives an incorrect dosage of the vaccine, our care teams follow the guidelines developed by the CDC. There is no data to show that an incorrect dosage of the COVID-19 vaccine negatively impacts a child. Parents are encouraged to speak with their pediatrician should they have questions specific to their child’s experience with the vaccination process.”

The guidelines from the Centers for Disease Control said that children who get higher doses of the COVID-19 vaccine than what is prescribed to them should not get a repeat dose.