As Korea bakes through a record-setting heat wave and demand for cooling surges, a possible power crisis is raising concerns for medical institutions that store and administer COVID-19 vaccines, many of which are smaller clinics unlikely to be equipped with a backup source of electricity.

With sizzling weather of over 30 degrees Celsius set to continue, the national electric grid is already stretched thinly, according to updates from the Korea Power Exchange. At one point in the past week, the nation’s power reserves fell to as low as 7 gigawatts and the reserve margin came to 7 percent, well below the recommended levels for stable power management of 10 percent.

Amid tight power supplies, three retired reactors had to be rebooted over the last 11 days, in an apparent backdown from Moon Jae-in administration’s push for a nuclear phase-out.

Managing heat risks is more crucial now that the mRNA-type Pfizer and Moderna vaccines -- which have so far been handled only at vaccination sites operated directly by the Korea Disease Control and Prevention Agency -- are being offered at regular clinics. Currently, there are around 13,000 such clinics that have been entrusted to carry out vaccinations.

“One of the challenges facing the summer vaccine drive is potential power shortfalls,” said infectious disease specialist Dr. Kim Woo-joo of Korea University Medical Center. A temperature deviation outside of the acceptable range can lead to the loss of vaccine effectiveness, he said.

“Hospitals, usually have standby power systems and high-performance refrigerators for storing blood and other temperature-sensitive medical products, are not so much at risk. But for smaller clinics, it’s a different story,” he said.

Most clinics are “practically defenseless” against a power outage, according to Dr. Choi Seung-jun, the vice president of Seoul’s Yongsan district medical association. The refrigerators where vaccines are stored have special sensors that alert the staff of deviations in temperatures, but that is unlikely to help if power goes out altogether, he said.

“Very few clinics are equipped with their own power generators to keep refrigerators running should a blackout take place,” he said. “We will have to dispose the vaccines if they are left to sit out in the heat for too long.”
 

Dr. Jang Hyun-jae, who has been in several meetings with health officials as a member of the primary care doctors’ group, said there have been “no discussions whatsoever, much less guidelines, on how clinics can respond to power cuts.” The latest meeting took place as recently as Wednesday.

“I don’t think there has been a chance yet to plan and prepare for scenarios where vaccine refrigerators are affected by a power outage,” he said. 

Jang said clinics also sometimes shouldered the responsibility of bringing the vaccines themselves using a container that they had to acquire on their own.

“In the heat, our staff are having to travel back and forth from the public health center to fetch the vaccines, which arguably raises the risk of temperature excursions along the way,” he said.

Things were expected to get more complicated in August, he added, when vaccine eligibility widens to anyone aged 18 and above. The age-based rollout opened up to people in their mid- to late-50s this week.

Dr. Ma Sang-hyuk, the vice president of the Korean Vaccine Society, said the public health office should at least provide the clinics with guidelines on how to manage vaccine storage during a power outage. 

“For instance, you should keep refrigerators closed until power is restored so that vaccines will stay cool for longer. Record the temperature inside the refrigerator as soon as power is restored. Also take note of the duration of the outage,” he said. “Then based on the information, health officials will need to consult the pharmaceutical companies to determine if the vaccines are still viable.”

More than 7,000 doses of vaccines have already gone to waste due to exposure to unsafe temperatures since the vaccination campaign began here in February, according to Rep. Shin Hyun-young of the parliamentary committee for health and welfare.

Yun Jeong-hwan, who is leading the national health agency’s vaccine distribution and inventory management team, said Thursday that the agency was requiring clinics to have thermometers and other special devices to prevent cold chain failures.

“As a rule, the agency is in charge of vaccine transportations, but exceptions have been made on rare occasions,” he said.

As for measures to protect vaccines from a power outage, he said the agency will “continue to work to ensure that cold chain is maintained at all times.”

By Kim Arin (arin@heraldcorp.com)