The Vaccine Saga: Comparison is the thief of joy

By Dr Vinod RMT Balasubramaniam
Molecular virologist
Jeffrey Cheah School of Medicine and Health Sciences

A lot of misinformation about the COVID-19 vaccines are being spread throughout social media. There should be a bridge between the scientific community and the public regarding relaying information in a simplified way.

Science is real because experimental pieces of evidence back it. Vaccines have been one of the biggest success stories of modern medicine. Throughout history, vaccination has proven to be one of the most critical cost-effective measures for controlling and preventing infectious diseases and preventing millions of deaths worldwide every year.

In the history of medical sciences, rarely has a vaccine been developed in less than five years. The vaccine against SARS-CoV2 was the fastest ever vaccine to be developed within one year of the outbreak. This posed a lot of questions regarding the safety and efficacy of the vaccine.

When scientists began seeking a vaccine for the SARS-CoV-2 coronavirus in early 2020, they were careful not to promise quick success. But by the start of December 2020, the developers of several vaccines had announced excellent results in large trials, with more showing promise. And on 2 December 2020, a vaccine made by Pfizer, one of the world's premier biopharmaceutical companies, with German biotech firm BioNTech, became the first fully-tested immunisation to be approved for emergency use.

Scientists developed COVID-19 vaccines quickly because of years of previous research on related viruses and faster ways to manufacture vaccines, enormous funding that allowed firms to run multiple trials in parallel, and regulators moved more quickly than usual.

Pfizer's COVID-19 vaccine efficacy is 95 per cent, Moderna's is 94 per cent, and Johnson & Johnson's is 66 per cent. But what do these numbers mean? One common misunderstanding is that 95 per cent efficacy implies that 5 per cent of vaccinated people were infected with the virus in the Pfizer clinical trial. But that's not true. The actual percentage of vaccinated people in the Pfizer and Moderna trials who got COVID-19 was about a hundred times lesser than that: 0.04 per cent.

The 95 per cent means that vaccinated people had a 95 per cent lower risk of getting COVID-19 than the control group participants, who weren't vaccinated. In other words, vaccinated people in the Pfizer clinical trial were 20 times less likely to get COVID-19 than the control group.

The public cannot compare the efficacy rates of all the vaccines head-to-head. For example, one might perceive that both the Pfizer and Moderna vaccines are the best due to the 94-95 per cent efficacy shown. In contrast, AstraZeneca only indicates 76 per cent. The Pfizer and Moderna vaccines were tested before newer, more contagious variants were widespread, making a difference in trials. They were also tested in different groups of people and environment. The bottom line is that Johnson & Johnson, Moderna, Pfizer, and AstraZeneca vaccines are all incredibly effective at preventing severe disease progression, hospitalisation, or death.

The Pfizer and Moderna vaccines have gone through three phases of trials involving at least 40000 people. Though the reactogenicity was substantially more significant in some people than in others, particularly for systemic reactions, including fatigue, headache, chills, fever, and joint pain, the vaccines are safe.