"If You Felt Very Sick After Pfizer First Dose, You Might Have Had COVID-19..."

A COVID-19 vaccine is placed in front of Pfizer's company logo. [Image source=Yonhap News]

[Asia Economy Reporter Hwang Sumi] There is a claim that if you experienced severe pain after the first dose of the Pfizer vaccine, you might have been infected with COVID-19.

According to JTBC on the 20th, mRNA vaccines like Pfizer or Moderna can cause more severe side effects after the second dose because antibodies develop in the body after the first dose.

However, people who have had COVID-19 already have antibodies, so the immune response after the first dose can be similar to that of the second dose.

According to this study, people who had COVID-19 are about 3 to 4 times more likely to experience side effects after the first dose of an mRNA vaccine. Fatigue, headaches, and fever were also more severe. However, side effects after the second dose were rarely observed.

In an interview with JTBC, Professor Cheon Eun-mi of the Department of Respiratory Medicine at Ewha Mokdong Hospital said, "Those who have been infected are essentially the same as having already received the first dose. Because a booster effect appears, side effects can be stronger." She also explained that it has been reported that antibodies are produced dozens of times more.

However, the researchers added that the absence of side effects does not mean the vaccine is ineffective. They also said this applies to breakthrough infections.

According to the JTBC report on the same day, breakthrough infections?cases where infection occurs even after completing vaccination?have the effect of an additional dose called a booster shot.

In Korea, the breakthrough infection rate is known to be about 0.03%, and most cases have mild symptoms.

Professor Jung Jae-hoon of the Department of Preventive Medicine at Gachon University College of Medicine explained, "From a scientific standpoint, being infected again after completing vaccination could improve the ability to induce antibodies."

However, long-term transplant patients using immunosuppressants are at very high risk. For this reason, the United States and Israel are rushing to administer booster shots.

JTBC also reported that as variant viruses spread, it remains to be seen how long the effect of strengthened antibodies will continue.

This content was produced with the assistance of AI translation services.