The U.S. Centers for Disease Control and Prevention (CDC) is investigating the death of a 13-year-old Michigan boy after he got his second dose of the Pfizer vaccine.

The connection between the Michigan boy's death and the vaccine has not yet been established. The boy, Jacob Clynick, had no underlying health conditions when he died in his sleep shortly after getting the second Pfizer shot, New York Daily News reported.

Saginaw County medical examiner Dr. Russell Bush said they are currently looking at toxicology, tissue reports, and blood work.

Bush noted that there would be discussions with the CDC and the Michigan Department of Health and Human Services. He added that they are looking at potential problems related to the Michigan boy's death.

For her part, CDC spokeswoman Martha Sharan told WSET-TV that the CDC is aware of the Michigan boy who died after receiving a COVID-19 vaccination.

Sharan said this case is currently under investigation, and it is premature to designate a specific cause of death until the probe is complete.

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The Michigan Boy's Death After Second Dose of Pfizer

Jacob Clynick had just completed eighth grade when he got his second dose of Pfizer at a Walgreens store on June 13, according to his aunt, Tammy Burages.

She noted that the Michigan boy was healthy and had no known underlying medical conditions, Detroit Free Press reported. Burages said Jacob Clynick complained of common post-vaccine symptoms within the two days between getting the Pfizer vaccine and dying. 

The Michigan boy had reportedly complained of fatigue and fever. Burages added that Clynick had a bit of stomachache too. However, it was not severe to cause serious concerns.

His aunt said the Michigan boy only went to sleep that night and never woke up. Burages noted that the preliminary autopsy findings found that the 13-year-old boy's heart was enlarged when he died, and there was fluid around his heart.

However, the Michigan Institute of Forensic and Science would not confirm the said preliminary findings. Randy Pfau, director of operations for the institute, said the only information they can verify is that they are managing the investigation.

Pfau added that it is still an ongoing investigation and could take three to five months to complete. Meanwhile, Jacob Clynick's aunt hopes that federal investigators will at least find some clues from his autopsy investigation.

Pfizer Vaccine on Adolescents

Shortly after the Food and Drug Administration (FDA) authorized the use of the Pfizer vaccine in young people, federal agencies had started receiving reports of mild chest pain and other signs of possible heart inflammation, NPR reported.

The condition, known as myocarditis, was found in a small percentage of teens and young adults soon after receiving the vaccination.

More than 300 cases of heart inflammation have been recorded after getting Pfizer or Moderna COVID vaccine. This was reported mostly in teens and young adults between 12 and 39 years old.

The CDC said these incidents do not change the main recommendation that all people 12 and older should be vaccinated. However, if a person develops heart inflammation at the first dose of the mRNA vaccines, the second dose should be delayed until the normal condition of the heart has been restored.

The CDC noted that most people who have experienced the side effect have recovered from symptoms and are doing well.

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