A researcher has claimed that the messenger RNA COVID-19 vaccine can increase serious adverse events in people, including sudden cardiac deaths.

Joseph Fraiman, the lead author of the peer-reviewed research that re-analysed Pfizer & Moderna trials for mRNA COVID-19 vaccine, has tweeted: "I believe the mRNA COVID-19 vaccines need to be withdrawn".

"We found the vaccine increases serious adverse events at a rate of one in 800. At the time of the publication, my co-authors and I did not believe our single study warranted the withdrawal of messenger RNA vaccines from the market. However, since its publication, multiple new pieces of evidence have come to light, and this has caused me to re-evaluate my position," said Fraiman in a video that surfaced online.

In another tweet, he mentioned that the US Foods and Drug Administration (FDA) published study surveillance data finds the Pfizer COVID vaccine increases the risk of lung blood clots by 50 per cent.

Moreover, Fraiman said he and his team have conducted multiple autopsy studies that provide "essential conclusive evidence" that vaccines induce sudden cardiac death.

"Schwab et al. study examined vaccine-induced myocarditis deaths, of 35 autopsies 20 days from the vaccine, 5 likely or possibly vaccine myocarditis but another 8 deaths, under 65 no pre-existing conditions, total 13 (37 per cent) possibly vaccine-induced deaths, needs further investigations," he tweeted.