Vaccine reactions in 5 states caused by anxiety, CDC finds

It was anxiety — and not a problem with the shots — that caused reactions in dozens of people at coronavirus vaccine clinics in five states, U.S. health officials have concluded.

Experts say the clusters detailed Friday by the Centers for Disease Control and Prevention are an example of a phenomenon that’s been chronicled for decades from a variety of different vaccines. Basically, some people get so freaked out by injections that their anxiety spurs a physical reaction.

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“We knew we were going to see this” as mass Covid-19 vaccine clinics were set up around the world, said Dr. Noni MacDonald, a Canadian researcher who has studied similar incidents.

The CDC authors said the reports came in over three days, April 7 to 9, from clinics in California, Colorado, Georgia, Iowa and North Carolina. The investigation was based on interviews with, and reports by, clinic staff.

Many of the 64 people affected either fainted or reported dizziness. Some got nauseous or vomited, and a few had racing hearts, chest pain or other symptoms. None got seriously ill.

All received the Johnson & Johnson vaccine, and four of the the five clinics temporarily shut down as officials tried to sort out what was happening. Health officials at the time said they had no reason to suspect a problem with the vaccine itself.

Of the three Covid-19 vaccines authorized in the U.S., only J&J’s requires just one dose. That probably makes it more appealing to people who are nervous about shots and might leave them “more highly predisposed to anxiety-related events,” the CDC report said.

Some of the sites advertised they were giving J&J shots, noted Dr. Tom Shimabukuro, who leads the CDC’s Covid-19 vaccine safety monitoring work and is one of the study’s authors.

The CDC found that about a quarter of the people reporting side effects had similar things happen following past vaccinations.

The post-shot reactions differ from a very rare kind of side effect that led to a pause in administration of the J&J vaccine. At least 17 vaccine recipients have developed an uncommon kind of blood clot that developed in unusual places, such as veins that drain blood from the brain, along with abnormally low levels of the platelets that form clots.

Other types of side effects from the coronavirus vaccines are not unusual. Another CDC report released Friday looked at side effects reported by more than 300,000 J&J vaccine recipients. More than half said they experienced a sore arm, fatigue or headache. A third reported fever or chills, and about a fifth said they were nauseous.