Government: "Flu Vaccines Are Safe"...480,000 Doses Recalled Over Efficacy Concerns (Comprehensive)

KDCA and MFDS Announce Investigation Results on Suspected Influenza Vaccine Exposed to Room Temperature
"Improper Temperature Management Found During Transport, No Impact on Quality"

An influenza vaccination notice posted at the entrance of a hospital in Seoul

[Asia Economy Reporter Choi Dae-yeol] The government has decided to recall 480,000 doses of influenza (flu) vaccines that were exposed to room temperature or dropped below 0℃ during transportation, indicating improper temperature management. Although the quality of vaccines with improper temperature management is not compromised, this measure aims to completely eliminate the possibility of distributing vaccines with reduced efficacy. Free vaccinations for middle and high school students and the elderly will resume around the 12th.

The Korea Disease Control and Prevention Agency (KDCA), the Ministry of Food and Drug Safety (MFDS), and local governments concluded this decision on the 6th after completing quality inspections and on-site investigations of the problematic flu vaccines. Earlier, on the 21st of last month, reports were received by authorities about issues during transportation, such as vaccines being placed on the ground in some regions. Consequently, the government temporarily suspended the free national immunization program and conducted quality investigations. They examined whether the cold chain was properly maintained, whether vaccines with improper temperature management were safe and effective, and whether quality was preserved.

On the 23rd of last month, citizens visiting the Korea Health Management Association Health Promotion Clinic Seoul Western Branch in Gangseo-gu, Seoul, received paid flu vaccinations.

Sinsung Pharmaceutical Supplied 5.39 Million Doses to 11,808 Locations
Most Transport Times Outside 2~8℃ Within 3 Hours

Sinsung Pharmaceutical, responsible for distributing the problematic vaccines, supplied 5.39 million doses (one dose equals one vaccination) to 11,808 vaccination sites (public health centers and medical institutions) across 17 cities and provinces nationwide from the 10th to the 21st. The originally contracted supply volume was 5.78 million doses, but 390,000 doses were not supplied due to suspension following the report.

First, it was confirmed that the storage temperatures maintained by Sinsung Pharmaceutical and DL Pharm (the subcontractor) were appropriate. However, some issues occurred during distribution to each region. It was revealed that an 11-ton vehicle transporting vaccines to the Honam region placed vaccines on the outdoor parking lot floor before distributing them with a 1-ton vehicle. Temperature records attached to each vehicle were reviewed to determine whether the appropriate temperature range (2~8℃) was maintained during transportation.

The temperature was recorded automatically every 10 or 30 minutes inside the vehicles. During this period, there were 391 transport trips by the 1-ton and 11-ton vehicles combined, with 196 trips temporarily exceeding the appropriate temperature range. The average duration outside the standard temperature was 88 minutes, with average maximum temperatures of 14.4℃ (11-ton) and 11.8℃ (1-ton), and average minimum temperatures of 1.1℃ (11-ton) and 0.8℃ (1-ton). Some vehicles were found to have temperatures dropping below 0℃ at times.

When combining records from both vehicles, about 88% of the time outside the standard temperature lasted less than 3 hours. One trip by the 1-ton vehicle exceeded the appropriate temperature for 800 minutes, but the temperature deviation was around 10℃, which was not significant. The government explained that although some deviations occurred, they were within a reasonably predictable range. Kim Sang-bong, Director of the Biopharmaceutical Division at the MFDS, stated, "The WHO acknowledges that short-term temperature deviations during vaccine distribution are unavoidable," adding, "Therefore, stability testing reflecting expected exposure is recommended."

A notice for free flu vaccinations is posted at a hospital in Seoul city./Photo by Hyunmin Kim kimhyun81@

Both Suspected Room Temperature-Exposed and Harsh Condition Vaccines Passed Quality Tests
No Quality or Efficacy Issues, but 480,000 Doses with Management Deficiencies or Uncertainties to be Recalled

They also examined whether vaccines supplied through Sinsung Pharmaceutical and those deliberately subjected to harsh conditions had any quality or efficacy issues, but no significant abnormalities were found. Seven to nine items were tested across key areas, including antigen protein content tests to assess efficacy and pyrogenicity tests to confirm safety. From five regions where reports were received (Gwangju, Jeonju in Jeonbuk, Gyeryong in Chungnam, Yangcheon and Guro in Seoul), 750 doses were collected and tested on all items required for national batch release approval, all of which passed. The tests included sterility tests that take about two weeks.

Additionally, 1,350 doses from nine regions suspected of improper temperature management were collected and tested, all yielding satisfactory results. Furthermore, 58 remaining doses from a nursing hospital in Incheon, where a death occurred after vaccination, were collected and tested, also passing. After expert consultation, the government concluded that the death cases at this hospital were due to underlying diseases unrelated to the vaccine.

Stability tests assessing how well vaccines maintain stability under external temperature changes such as heat showed minimal impact. All eight tested items maintained quality after being kept at 25℃ for 24 hours. Five items maintained quality for over 72 hours, and one item for over 48 hours at 37℃. Two items showed some changes in antigen protein content and quality after 12 hours at 37℃. Additional evaluation of these two items at 25℃ confirmed quality maintenance for 24 hours.

Professor Seong Baek-rin of the Department of Biotechnology at Yonsei University is answering questions from the press following his explanation of the quality inspection and on-site investigation results related to the influenza (flu) vaccine at the Korea Disease Control and Prevention Agency in Cheongju, Chungbuk, on the afternoon of the 6th.

Based on these investigation and test results and expert consultations, the government judged that the vaccines are safe as their quality is unaffected. However, only some vaccines with potential efficacy reduction will be recalled. These include approximately 270,000 doses exposed below 0℃ even briefly according to transport vehicle records, 170,000 doses temporarily placed on the ground during transport in the Honam region, 2,000 doses with significantly longer temperature deviations than others, and 30,000 doses without temperature records, totaling 480,000 doses. Whether these will be discarded after recall has not yet been decided.

Professor Sung Baek-rin of Yonsei University's Department of Biotechnology explained, "(The investigation results) showed that most exposures lasted about 3 hours, with a maximum of 16 hours, but even exposure up to 24 hours does not cause concerning reductions in vaccine efficacy or safety issues such as external contamination, which was a consensus among participating experts."

He added, "If vaccines freeze and thaw, precipitates can form, causing syringe blockage and other issues during vaccination. Therefore, cases without confirmed temperature records or vaccines stacked outdoors were decided to be recalled to enhance safety, although there are no quality problems."

Jung Eun-kyung, head of the Central Disease Control Headquarters (Director of the Korea Disease Control and Prevention Agency), is answering questions from reporters after explaining the results of quality inspection and on-site investigation related to the influenza (flu) vaccine at the Korea Disease Control and Prevention Agency in Cheongju, Chungbuk, on the afternoon of the 6th. <이미지:연합뉴스>

554 Vaccinated with Recalled Vaccines in 7 Regions
No Adverse Reactions... Free Vaccinations to Resume on 12th After Recall

Among the 5.39 million doses under investigation, 3,045 people in 16 regions had been vaccinated as of 2 p.m. on the day. Among them, 554 people in 7 regions received the recalled vaccines. There were a total of 12 reported adverse reactions related to the problematic government-procured vaccines (3 cases involved recalled doses), but all are currently symptom-free.

Free vaccinations for middle and high school students will resume from the 12th. While recalling the problematic vaccines, the government will review whether to adjust the previously scheduled vaccination plans and finalize the decision.

Jung Eun-kyung, Director of the KDCA, stated, "For the additional 6.5 million doses to be delivered through national procurement, we will enhance cold chain maintenance and monitoring systems. In the mid to long term, we will establish a task force with the Ministry of Health and Welfare and the MFDS to develop improvement measures for vaccine cold chain management." She added, "We will continuously monitor adverse reactions in those vaccinated with the recalled vaccines and conduct medical reviews to determine if re-vaccination is necessary."

This content was produced with the assistance of AI translation services.