Authorities: Those under 30 who received 1st dose of AZ vaccine will get AZ vaccine for 2nd dose as well

Pfizer Vaccine Cross-Vaccination Possibility Ruled Out

[Image source=Yonhap News]

[Asia Economy Reporter Kim Ji-hee] The government has reaffirmed its stance to administer the same AstraZeneca (AZ) COVID-19 vaccine for the second dose to recipients under 30 years old who have already received the first dose of the AZ vaccine. Previously, the AZ vaccine was excluded from the vaccination target for those under 30 due to rare blood clot controversies, but if the first dose was already administered without any adverse effects, the second dose will also be given.

On the 12th, Hong Jeong-ik, head of the COVID-19 Vaccination Response Promotion Team’s Vaccination Planning Team, said at a briefing, "South Korea has not yet decided on heterologous vaccination," adding, "We need to review the scientific evidence." He explained, "It is predicted that many young people under 30 experienced systemic adverse reactions during the first dose of the AZ vaccine," but "the frequency of adverse reactions decreases with the second dose."

Hong also stated, "Even if you had severe chills and fever during the first dose, the frequency significantly decreases with the second dose," and "there are no restrictions on vaccination for those who did not experience adverse reactions during the first dose." This means that heterologous vaccination, where those under 30 who received the AZ vaccine for the first dose receive the Pfizer vaccine for the second dose, is not allowed.

Regarding the judgment that the second dose will also be safe if there were no severe adverse reactions during the first dose, he explained, "The safety of vaccines is proven through clinical trials and then approved," adding, "If the reaction is caused by the vaccine, it is theoretically highly likely that if no problems appeared during the first dose, none will appear during the second dose."