19 travelers from Europe tested positive for COVID-19

Nineteen people have tested positive for COVID-19 on Sunday, the first day when South Korea started testing all travelers from Europe. The number of travelers from Europe arrived in the nation was 1,444 on the day, and 152 showed symptoms and 1,292 had no symptom. Eleven out of 152 people who showed symptoms tested positive, and eight out of the symptomless 1,292 also tested positive. There are possibilities of finding additional patients as the test is still in progress. Without the test, asymptomatic patients could have been released to local societies and become a source of infection.

This shows the necessity of strengthened quarantine on those who come from countries with serious level of infection such as the U.S. The number of travelers arriving in South Korea is about 3,000, which is double the number of those from Europe. The number of patients recently exceeded 43,000 in the U.S., which is the third after China and Italy.

The South Korean government began testing all travelers from Europe on Sunday and has been actively monitoring them or ordering a two-week self-quarantine. But it tests travelers from the U.S. only when they show symptoms. Considering the fact that eight among the symptomless group tested positive in one day, asymptomatic patients who slipped through the quarantine could spread the virus to local communities.

The City of Seoul announced Tuesday that it was reviewing methods of obligating all travelers from the U.S. to isolate themselves for two weeks. But public health authorities need to act on it to curve the inflow of the virus from overseas. They need to push ahead with inspection on all travelers from countries with infection including the U.S. arriving in South Korea.

Of course, inspecting all travelers could put a significant burden on the finance, administration and medical system. The government also needs to consider whether the measures it is about to take are symmetrical with those taken by the U.S. But delay of one day in the quarantine may have a huge impact. The virus has gone global and infected more than 390,000 people in more than 190 countries. Some 100 are newly diagnosed every day still in South Korea. Considering the burden of inspecting all travelers, health authorities must review banning the entry of those from countries with high infection rates.