A new study has found that adolescents and young adults suffering from myocarditis (a form of inflammation in the heart) after getting COVID-19 vaccinations tend to have mild cases. They also recover rapidly.

Researchers from the University of Utah and Boston Children’s Hospital evaluated the health records of 139 people under 21 years old who had the same condition after vaccination.

One in five of these patients did not require intensive care. None required oxygen support, or even died. 

Average hospitalization time for patients was two days.

Although myocarditis can occur as a side effect to Covid vaccines (see study), it is manageable and may outweigh the risk.

However, the researchers warn that any future studies must focus on long-term outcomes of these patients.

Young adults and teenagers who experience myocarditis, a rare side effect of Covid vaccines, typically have relatively mild cases and recover quickly, a new study finds. Pictured: A high school student in Freeport, New York receives a vaccine dose on campus, July 15, 2021

New research has shown that teenagers and young adults who have myocarditis (a rare side effect from Covid vaccines) tend to experience mild symptoms and heal quickly. Pictured: On July 15, 2021, a high school student in Freeport (New York) receives an on-campus vaccine.

Covid vaccine doses adminsitered have increased sharply in the U.S. in recent weeks, to almost one million doses given a day, as children ages 5 to 11 are now eligible for Pfizer's vaccine

The U.S. has seen an increase in covid vaccination doses to over one million per day. This is because children aged 5-11 years old are now eligible to receive the Pfizer vaccine.

As of Tuesday morning, approximately 71% of Americans had received at least one dose (or more) of the Covid vaccine. 60% are completely vaccinated.

According to the Centers for Disease Control and Prevention, this means that more than half of Americans aged 12 and older are fully vaccinated.

Overall, the Pfizer, Moderna, and Johnson & Johnson vaccines have been deemed safe and effective at protecting against Covid by health officials – but side effects have been reported in a small number recipients.

Myocarditis is a serious side effect that can occur. This inflammation of the heart muscle, usually caused by an immune response to the body’s system, causes severe damage.

Myocarditis was reported in the past as an adverse reaction to shots that protect against smallpox and flu.

Myocarditis is a common side effect of the Covid vaccines.

A study published Monday in the journal Circulation provides new information on myocarditis cases among teenagers and young adults.

The study was conducted by researchers from several children’s hospitals in the United States, including Boston Children’s Hospital and the University of Utah.

Retroactive data was collected from 26 children’s medical centers in the U.S.A. and Canada by scientists.

The data collected was limited to patients younger than 21 years old who presented with symptoms or heart imaging that matches myocarditis within the first 30 days after receiving a Covid vaccination.

The study involved 140 cases of myocarditis in 139 children admitted to pediatric medical centers before July 4, 2021.

The majority (91%) of patients were men, while 66 percent were from the white race. Median age was 16

49 of the 140 cases of myocarditis were confirmed based upon CDC criteria. The remaining 91 were considered probable.

Most of the myocarditis patients (131, or 94 percent) had received the Pfizer vaccine, while five had received Moderna’s vaccine and one had received Johnson & Johnson’s.

Patients were more likely to develop myocarditis following their second vaccination jab. 91 percent of patients had this condition after the first dose.

Researchers concluded that patients who had myocarditis were generally well and recovered rapidly.

Just 19% (26 patients) needed to be admitted to an intensive care unit. Two patients only required medication that would force their circulatory system to work.

Patients did not require oxygen supplementation and they were all healthy.

It took patients just two days to leave the hospital. This is indicative of a quick recovery.

“These data indicate that the majority of cases of COVID-19-related myocarditis among people under 21 years old are mild and quickly resolve,” said Dr Dongngan Truong (a University of Utah pediatrician and the first author of the study).

“We were delighted to see this type of recovery.

“However, further research is needed to understand long-term outcomes for patients with COVID-19-related myocarditis. 

More studies are needed to study any potential long-term outcomes of myocarditis after vaccination. Pictured: A Covid vaccine record card and #IGotTheShot sticker

To determine the long-term effects of vaccination on myocarditis, more research is needed. Photo: Covid vaccination record card with #IGotTheShot sticker

Myocarditis sufferers experienced 99 percent of the symptoms, but fewer experienced chest pain (31%) and shortness-of-breath (27%) respectively.

An estimated 81 percent of the patients received anti-inflammatory medication treatment, with others receiving intravenous or steroids.

Researchers couldn’t determine the best treatment for myocarditis recovery through this study because of its design.

But, the researchers noted that 12 patients (or 8.6%) had experienced ‘complete clinical improvements’ without anti-inflammatory treatments.

This research follows similar reports which found myocarditis post-vaccination cases can be treated easily and have high recovery rates.

Truong stated that it was important for both health professionals and the general public to know the signs and symptoms of early myocarditis. This is especially true as the vaccines are becoming more readily available to children. 

According to NBC, more than 2 million children below 12 years old had received vaccination doses by December 1.

Truong and other researchers also pointed out in the paper that further research was needed to examine risk factors associated with post-vaccination myocarditis. This includes why it is so common among young men than for boys.

Although it is possible that there are underlying genetic and immune responses differences in men and women, more research is required.

The study adds support to what we’ve been seeing. People who have had COVID-19-related myocarditis diagnosed early and correctly are more likely to experience mild symptoms and a quick recovery time, said Dr Donald Lloyd-Jones of the American Heart Association.

“These findings also back the American Heart Association’s belief that COVID-19 vaccinations are safe and highly effective, fundamental to saving lives and protecting families and communities from COVID-19 and ending this pandemic,” Lloyd-Jones continued.

Lloyd-Jones also noted that ‘the benefits of COVID-19 vaccination… far exceed the very rare risks of adverse events, including myocarditis.’

It is more common for MIS–C and Covid patients to end up in the ICU and require oxygen support than it is to succumb to myocarditis.

Lloyd-Jones urged parents to get their child immunized as quickly as possible.