Smallpox Vaccine Recipients Died From Heart Inflammation, Autopsies Find

Zachary Stieber
By Zachary Stieber
May 20, 2023US News
Smallpox Vaccine Recipients Died From Heart Inflammation, Autopsies Find
A solider with the U.S. Army's 101st Airborne waits for a series of tests and inoculations at Ft. Campbell, Ky., on Feb. 11, 2003. (Rusty Russell/Getty Images)

Several U.S. military personnel who received a smallpox vaccination died from heart inflammation while others had not recovered from the same inflammation years after first experiencing the condition, an in-depth review of medical records has found.

Autopsies of two male military members in their 20s who suddenly died uncovered heart inflammation, or myocarditis. There were also signs that heart inflammation contributed to two additional deaths, one an 18-year-old male and the other a 23-year-old female.

Researchers also found that 348 members survived myocarditis and/or a related condition, pericarditis, but that it took at least months for each to recover, with some still not having recovered years down the line.

Some 2.5 million service members received a smallpox vaccine between Dec. 1, 2002, and Dec. 31, 2016, the time period covered in the study.

The lead researcher of the study, which was published by PLOS One in May 2023, declined to comment. Nearly all of the researchers are employed by the Defense Health Agency (DHA). They wrote in the paper that the findings “draw attention to potential long-term morbidity and possible chronic (>3 months) or recurrent (return after a quiescent interval of 4–6 weeks) symptoms in pericarditis and myocarditis.”

The U.S. Department of Defense, of which the DHA is part, declined to comment. The DHA did not respond to a request for comment. Its website does not include the newly reported information.

Most Affected Recovered

Researchers combed through health care records and other documents from cases reported to the Vaccine Adverse Event Reporting System. The cases, which were verified or designated as suspected after the research was conducted, were among members who received the Dryvax or ACAM2000 smallpox vaccine between Dec. 1, 2002, and Dec. 31, 2016.

While more than 5,000 adverse events following smallpox vaccination were reported, researchers narrowed down the list by applying the U.S. Centers for Disease Control and Prevention case definitions for myocarditis and pericarditis from 2003. They identified 352 cases, including the four deaths. For each case, they reviewed documents such as health care records, and confirmed some of the patients as suffering from myocarditis or pericarditis, while listing others as being suspected of suffering from one of the conditions.

Researchers then looked at additional records to see whether each member had recovered and, if they had, how long the recovery took.

Out of 306 cases with follow-up data, just 16 recovered in six weeks or less. An additional 194 recovered by one year. But 67 did not recover until one year or later, and 39 never fully recovered as of the most recent data available.

Researchers highlighted how most members recovered, even if it took a long time.

“Myocarditis/pericarditis following the smallpox vaccine is associated with full clinical and functional ventricular recovery in over 87 percent of cases,” they wrote. Some of the members, though, “experienced prolonged or incomplete recovery beyond 1 year,” the researchers acknowledged.

Heart inflammation usually triggers a hospital visit and patients are typically told to stop exercising for a period of time, among other restrictions. Symptoms can include fatigue, irregular heartbeat, and disease of the heart muscle. Several experts said it was good news that most patients recovered, but the lengthy recovery time, the condition being chronic for dozens of members, and the deaths sparked concerns.

The 39 members “hadn’t recovered,” Dr. Andrew Bostom, a heart expert based in Rhode Island who was not involved in the research, told The Epoch Times. “That’s concerning,” he said, particularly given those affected are “healthy young people that easily could have gotten away without getting the vaccine.”


The number of deaths was small, but further proof that vaccine-induced myocarditis can kill even previously healthy people.

Researchers said that for the two sudden deaths, there was very strong evidence that myocarditis was the cause. Autopsies and other information uncovered “no other causes,” they wrote.

One of the service members, a 26-year-old white male, had zero cardiac risk factors. He began showing symptoms such as fever and chills 10 days after receiving a smallpox vaccine. The member suddenly died six days later.

The other member was a 24-year-old white male with one cardiac risk factor and a higher body mass index. He suddenly died 12 days after vaccination, the same day he was hospitalized.

The third death was an 18-year-old black male with no cardiac risk factors. The member experienced fatigue and other symptoms during a 5-mile run eight days after vaccination. He was resuscitated and rushed to a hospital, but died five days later.

The other death was a 23-year-old black female with no cardiac risk factors who reported symptoms such as shortness of breath 10 days after vaccination and was hospitalized. She died 22 days later. There were signs myocarditis contributed to the third and fourth deaths, researchers said.

All four members who died were, according to medical records, in good health, “meeting military physical fitness standards, and without diagnoses impacting the ability to deploy or receive the SPV,” or smallpox vaccine.

While some smallpox vaccines were administered in years past, the military launched a larger program in 2002 that saw members deemed potentially at risk of a bioterrorism attack receive a smallpox vaccination. That led to millions of members receiving a shot.

The military in 2018 suspended mandatory administration of the anthrax or smallpox vaccines, with limited exceptions, but some members are still being vaccinated.

Heart issues are a known side effect of the smallpox vaccines. Myocarditis and pericarditis occur in approximately one in 175 first-time recipients of ACAM2000, which has been available since 2008, according to the U.S. Food and Drug Administration. Prospective military vaccinees are asked if they have a history of heart conditions, and administrators are warned to keep an eye out for vaccine-associated heart problems within 30 days of vaccination.

Insight Into Myocarditis After COVID-19 Vaccination?

COVID-19 vaccines also cause myocarditis, particularly in young males. Some of the patients have died. Long-term data for vaccinated people who suffered myocarditis is scarce, but the data that is available has shown that not all sufferers recover quickly.

About half of the cardiac MRIs conducted on 151 patients after at least 90 days showed abnormalities, such as scarring, U.S. Centers for Disease Control and Prevention (CDC) researchers reported in 2022.

In an update shared this year, the researchers revealed that 23 percent of 60 patients who responded to surveys said they were experiencing chest pain for one year or more from vaccination.

In the new paper, the military researchers said that their findings, including the lack of recovery in some people and the lengthy recovery in others, “appear similar to cases” following COVID-19 vaccination.

“However, long-term outcomes remain to be defined and may need to include prolonged stress reactions associated with an acute case of [myocarditis/pericarditis] in a previously healthy and fit vaccinee,” they added.

If the study is showing data that ends up being similar for the cases among COVID-19 vaccine recipients, “that’s not very reassuring,” Bostom said.

From The Epoch Times

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