As we have seen in the recent Ebola epidemic, a deadly, contagious disease ― unless completely contained in time ― can endanger national security as much as other threats. It seems the Korean health authorities have not learned any lessons from the outbreaks of the Ebola virus and other major epidemics.

It is a matter of great dismay and concern to hear that health authorities keep mishandling cases of the Middle East respiratory syndrome. A man who was suspected of being infected with the coronavirus that causes the disease, and kept under watch, has left for China.

The 44-year-old man was not diagnosed with the viral disease, but he was one of the about 60 people isolated at hospitals or homes after coming in contact with the MERS patients.

It is more incomprehensible that he left the country without the knowledge of officials, who had already faced criticism for mishandling the case of none other than his sister.

His sister, also in her 40s, was experiencing minor symptoms such as fever and headache after spending about four hours with her father, who contracted the virus from the first patient who was staying in the same hospital room. She asked for a test and voluntary quarantine.

But authorities rejected her request, saying that her symptoms were not so serious as to be tested and quarantined under the guidelines provided in the government manual. They said her temperature was lower than 38 degrees Celsius, the level required for testing under the manual, and she did not have acute respiratory problems.

As it turned out only five days later, the woman was confirmed to have contracted the deadly MERS coronavirus and was admitted to a government-designated hospital. This stupidity could have been prevented if any of the officials had the sense to be flexible with the manual, considering that she had stayed in a room occupied by a MERS patient.

As public criticism over the officials’ blind obedience to the government manual mounts, Health Minister Moon Hyung-pyo belatedly said the government would not be bound by the manual and take preemptive measures “under the assumption of the worst case possible.”

He also said authorities would set up a 24-hour monitoring system, and immediately test and quarantine anyone who shows any signs of abnormality after coming in contact with a patient.

It is more scary than unnerving that our health care system did not practice these basic, matter-of-course rules in responding to a disease with a fatality rate as high as 40.7 percent, for which there is no vaccine or treatment.

Given the lax response, it would be strange if the number of people who contracted the virus does not rise since the first case was reported May 20: It has grown to seven, including a doctor. We only hope it does not get worse.