Australian Research Declares mRNA Vaccines ‘Overwhelmingly Favourable’ Despite Causing Myocarditis

A man receives a COVID-19 vaccine at Sydney Road Family Medical Practice, in Sydney, Australia, on Jan. 10, 2022. (Jenny Evans/Getty Images)

Australian researchers who studied a 20-year-old man with symptoms of myocarditis after his second Pfizer COVID-19 jab have argued that mRNA vaccines are still “overwhelmingly favourable” for all eligible age and sex groups. This is despite the country’s medicines regulator noting that myocarditis and pericarditis rates were increasing each week as vaccination rates rise.

The research team, led by Joshua Wong from the Royal Melbourne Hospital, examined a patient who presented to the hospital with chest pain, fever, and sweats after his second dose of the Pfizer vaccine.

Reportedly, 12 hours after receiving the second dose, the patient started experiencing symptoms of headaches, night sweats, and chills and developed chest pain 48 hours later even though he was fine after his first dose 23 days prior.

The patient had no history of myocarditis, however, an ultrasound of the heart showed a decrease in function of the left ventricles generally associated with myocarditis, suggestive of possible vaccine-induced myocarditis.

Wong and his colleagues reported that the patient also had elevated troponin levels, as indicative of heart injury and markers indicating inflammation.

The patient was released from the hospital after making a full recovery in 24 hours. While there have been no reported deaths in Australia from vaccine-induced myocarditis, the patient was advised to avoid strenuous activity to allow healing of the heart muscle and was scheduled for a check-up in three months’ time.

The study’s authors thus concluded that given the scarcity, mild presentation, and clinical course of mRNA vaccine-related myocarditis, and the efficacy of vaccines in reducing SARS-CoV-2 infection, the benefit and risk assessment for the vaccines is “still overwhelmingly favourable for all age and sex groups.”

As of Jan. 30, there have been 1,369 cases of suspected myocarditis in Australia out of 35.9 million doses administered.

Australia is seeing slightly higher than estimated rates of myocarditis with 1.7 cases per 100,000 and 1.4 cases per 100,000 respectively for Moderna and Pfizer doses.

The Pfizer vaccine-related myocarditis incidence for males aged 12 to 17 is currently 6.7 and 10.9 per 100,000 people for first and second shots respectively. The Moderna vaccine has a higher incidence rate for males aged 12 to 17 at 8.5 and 15.4 per 100,000 for first and second doses.

However, given that the current background incidence of myocarditis (pdf) in the general population for Australians aged 18 to 34 is estimated at 37 per 100,000 patients in males and 16 per 100,000 patients in females, per year, the authors stated that vaccine-induced myocarditis is “an extremely rare and mild complication.”

The Australian government has also cited a non-peer-reviewed U.S. study that noted myocarditis was seen much more commonly in people with SARS-CoV-2 infection than in vaccinated people.

According to Australia’s medicines regulator, the Therapeutic Goods Administrator (TGA), as of Jan. 30, no likely cases of myocarditis have been reported for children aged 5 to 11, from the 913,000 vaccine doses given.

This comes despite the TGA noting in December 2021, that the incidence rate for heart conditions following COVID-19 vaccinations were rising each week, consistent with rates internationally.

“The number of reports of myocarditis is increasing each week, which is expected as the number of vaccine doses given also increases each week. We are closely monitoring the rates of myocarditis for all age groups and sex,” the TGA said.

As of Feb. 7, more than 93 percent (pdf) of people aged over 16 have received two doses in Australia with more than 44 percent of boosters administered to eligible people aged over 18.