SEOUL, South Korea (AP) — South Korea on Friday administered its first available shots of coronavirus vaccines to people at long-term care facilities, launching a mass immunization campaign that health authorities hope will restore some level of normalcy by the end of the year.

The rollout of vaccines come at a critical time for the country, which has seen its hard-won gains against the virus get wiped out by a winter surge and is struggling to mitigate the pandemic’s economic shock that decimated service sector jobs.

More than 5,260 residents and workers at 213 nursing homes, mental institutions and rehab centers will receive their first shots of a two-dose vaccine developed by AstraZeneca and Oxford University on Friday.

An unspecified number of patients and workers at 292 long-term care hospitals will also get the vaccine, according to officials at the Korea Disease Control and Prevention Agency.

Separately, doctors, nurses and other health professionals treating COVID-19 patients will begin receiving the shots developed by Pfizer and BioNTech from Saturday. The Pfizer-BioNTech vaccines, which South Korea obtained through the WHO-backed COVAX program, are expected to arrive at Incheon International Airport on Friday afternoon to be transported to five major COVID-19 treatment hospitals.

South Korea plans to complete injecting the first doses to some 344,000 residents and workers at long-term care facilities, which also include mental institutions and rehab centers, and 55,000 frontline medical workers within March.

The next available vaccines are likely to go to workers at general hospitals, paramedics, quarantine workers and people over 65 years in age before broader groups of adults begin receiving shots in summer.

South Korea plans to secure enough doses to vaccinate 79 million people this year, well over its population of 51 million, through bilateral negotiations with pharmaceutical companies and COVAX, which was established to promote global access to vaccines.

Officials aim to vaccinate more than 70% of the population by November, which they hope would meaningfully slow the virus and reduce risks of economic and social activity.

However, experts say a safe return to life without masks would be highly unlikely this year, considering the need to monitor the vaccines’ real-world effectiveness and the growing spread of virus variants that are feared to be more contagious.

As of Thursday, South Korea reported 88,516 cases of the coronavirus, including 1,581 deaths.