Health authorities are reviewing a possible expansion of eligibility for a second COVID-19 booster shot to those in their 50s amid rising concerns about a recent resurgence of the disease as new daily cases continue to climb.

Currently, those over the age of 60 and those that may be more susceptible to infection, such as people working in or staying at nursing facilities, are eligible for a fourth shot.

While the government previously considered opening the second booster shot to the general population, the focus has shifted to the prevention of severe virus cases in high-risk groups.

The government is expected to announce the decision on Wednesday along with a new set of antivirus measures for the summer.

The updated measures correspond to the confirmation by health authorities that the nation has entered a new wave of COVID-19, citing the fast spread of the highly contagious mutation of the Omicron strains, especially the new subvariant BA.5.