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Health experts answer questions about COVID-19 vaccine side effects

Vaccine
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On Tuesday, the Food and Drug Administration (FDA) and Centers for Disease Control (CDC) announced both organizations will stop using the Johnson & Johnson vaccine at federal sites after reports of extremely rare blood clots developed in certain individuals.

But despite those risks, which officials say developed in six recipients of more than 7 million who received the Johnson & Johnson vaccine, science has proven the remarkable effectiveness of the COVID-19 vaccines, in general.

The U.S. continues to set records for daily vaccinations at more than 3 million per day, according to the CDC, but some people are voicing concerns about possible flu-like side effects and reactions.

“In my 40 years of working with the vaccines, never had I heard people complain that they haven’t had side effects,” said Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia. “About 50 percent of people associated with the second dose of vaccine, especially those younger than 65 years of age, can have significant side effects.”

Those main side effects are fatigue, joint and muscle pain, and fever. It has led some to wonder whether or not they have been infected with COVID-19.

The answer is no.

Researchers say mRNA vaccines, the technology used in the COVID vaccines, do not inject your body with any of the virus. Instead, it instructs your body to produce certain antibodies. When your body produces those antibodies it releases proteins called cytokines and chemokines that control immune cell trafficking and can cause some of those flu-like symptoms.

“Having those side effects means that your immune system is activated. That’s a good thing,” said Offit.

“Symptoms are worse for women. They’re worse for younger people, but on the other hand, there’s a lot of people who don’t have any reactions at all,” added Dr. Gigi Gronvall, a senior scholar at the John’s Hopkins Center for Health Security.

Another question Gronvall says she has fielded is from people who do not feel side effects from the vaccine and ask if it is working.

That answer is yes.

Doctors say we all have a different set of proteins that regulate our immune systems, similar to cytokines and chemokines, and they can react differently to different foreign bodies. So, if you do not feel side effects, Gronvall says it just means your body’s makeup is different from someone who might have had a reaction to the vaccine.

“We’ve gotten a lot of questions from people who want to know ‘did my vaccine work?’ You know, maybe if they didn’t have any of those side effects they get a serology test,” she said.

A serology test looks for antibodies in our blood. Dr. Gronvall says there are not any tests designed to look specifically for the vaccine antibodies so if your test comes back negative saying you do not have them, it might mean it just missed them.

“People should just be rest assured that the vaccine is effective that they get,” she said.

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