The South Korean Drug Ministry has been slammed over a slow response to problematic flu vaccines that have been given to at least tens of thousands of people.

Friday evening, the Ministry of Food and Drug Safety said some 615,000 doses of flu vaccine would be banned from use after they were found to contain suspicious particles. This is in addition to the 480,000 doses that were declared unusable earlier following their exposure to out-of-range temperatures while being transported to clinics and hospitals.

But the ministry’s measures to stop the use of the vaccines with possible contaminants came three days late, according to ruling Democratic Party Rep. Jung Choun-sook.

Jung said during Tuesday’s National Assembly audit session that the Drug Safety Ministry was aware of the issues with the vaccines as early as Oct. 6, but waited until later that week to make the announcement. By failing to take action immediately, nearly 65,000 people were given shots that are feared to be ineffective and unsafe from Oct. 7-9, the lawmaker said.

“The ministry should have communicated the risks promptly and clearly with the public,” she said.

While the Drug Safety Ministry as well as the Korea Disease Control and Prevention Agency insist the affected vaccines are both safe and effective, Democratic Party Rep. Shin Hyun-young said the procedure has not been transparent enough to restore public trust.

“There needs to be assurance that the people who were administered the vaccines will not suffer side effects,” she said. So far, 12 people have reported experiencing adverse reactions such as pain and swelling around the injection site and fever.

Drug Safety Minister Lee Eui-kyung in response said there were “no known harms” from the vaccines with suspected contaminants, but that their use has been discontinued “out of caution.”

“The ministry plans to closely monitor patients who received the vaccines in question for any unusual reactions,” she said.

The vaccines that experienced varying degrees of cold chain failures have been approved for inoculation again, after an inspection by public health official concluded there were no safety or potency issues. While the investigation is not yet complete, the number of people inoculated with the heat-exposed vaccines amount to 3,045 as of the latest count.

Asked about potential shortages, Lee replied the vaccination program will be short of the planned coverage by an estimated 60,000 to 70,000 doses.

By Kim Arin (arin@heraldcorp.com)