By Sangmi Cha
SEOUL, May 20 (Reuters) - South Korea on Thursday said it
will conduct a clinical trial that mixes COVID-19 vaccine doses
developed by AstraZeneca Plc with those from Pfizer Inc
and others.
The decision comes as a growing number of countries look
into using different COVID-19 vaccines for first and second
doses amid supply delays and safety concerns that have slowed
their vaccination campaigns.
A health official said the trial will include around 500
military personnel who were vaccinated with a first dose of
AstraZeneca's COVID-19 shot.
The study will examine T cells - immune cells that can
destroy virus-infected cells - and neutralising antibodies in
those who were given a combination of doses, the health official
told reporters.
The timing and the size of the study has not been decided,
the health official said, but will involve a diverse age group.
South Korea's vaccination campaign has been hampered by
global shortages and shipment delays, deepening public
scepticism over Seoul's goal of reaching herd immunity by
November.
It has given first doses to just over 7% of its 52 million
population, the Korea Disease Control and Prevention Agency
(KDCA) data showed on Thursday.
KDCA reported 646 new confirmed cases of the coronavirus as
of Wednesday midnight, bringing total infections to 134,117,
with 1,916 deaths.
(Reporting by Sangmi Cha; Editing by Kirsten Donovan)