Experts have advised that people with certain heart-related ailments should consult their physician before taking these jabs.

Both Pfizer-BioNTech and Moderna vaccines are mRNA vaccines encoding the stabilised prefusion spike glycoprotein of SARS-CoV-2, the virus that causes COVID-19. Unlike vaccines that put a weakened or inactivated virus in your body to activate an immune response, these two Covid-19 vaccines (Pfizer-BioNTech and Moderna) used messenger RNA or mRNA to deliver a message to the immune system.

Florida Surgeon General Dr. Joseph A Ladapo said, "Today, we released an analysis on COVID-19 mRNA vaccines the public needs to be aware of. This analysis showed an increased risk of cardiac-related death among men 18-39. FL will not be silent on the truth, tweeted Ladapo.

The analysis was conducted by the Florida Department of Health (Department) through a self-controlled case series, which is a technique originally developed to evaluate vaccine safety

The study found a sharp 84% increase in the relative incidence of cardiac-related death among males 18-39 years old within 28 days following mRNA vaccination.

Patients with pre-existing cardiac conditions, such as myocarditis and pericarditis, should be extra cautious when considering vaccination and discuss it with their healthcare provider.

It reads, with a high level of global immunity to COVID-19, the benefit of vaccination is likely outweighed by this abnormally high risk of cardiac-related death among men in this age group.

Non-mRNA vaccines were not found to have these increased risks

"Studying the safety and efficacy of any medications, including vaccines, is an important component of public health," said Surgeon General Dr Joseph Ladapo.

"Far less attention has been paid to safety and the concerns of many individuals have been dismissed - these are important findings that should be communicated to Floridians," added Ladapo.

According to officials at Genova, the trial data showed that the vaccine was safe and well-tolerated. Immunogenicity measured at 2 weeks post-dose showed that GEMCOVAC-19 is non-inferior to Covishield.

The two-dose vaccine will have to be administered intramuscularly, 28 days apart.

Meanwhile, India's first mRNA Covid-19 vaccine Gennova's GEMCOVAC-19 will be available soon for emergency use. The company has conducted phase 2 and phase 3 data trials on 4000 participants to evaluate vaccine safety, immunogenicity and tolerability. India's drug regulator Drugs controller general of India (DCGI) is expected to give EUA to the vaccine soon.