For most of the year, South Korea has kept its coronavirus numbers so low it was the envy of the world. Now, the country is grappling with the most elusive wave of infections it has seen, just as other nations prepare to roll out vaccinations.

South Korea’s daily number of new cases was once as low as two per day. That number soared to​ 682 on Thursday, with health officials warning it could reach record highs in coming days. On Wednesday​, 686 new cases were reported, the highest daily count since Feb. 29.

"We must exert all we can, considering this our last hurdle to clear ​in our efforts to curb the coronavirus before vaccines and treatments come online,” President Moon Jae-in said this week. He has instructed his government to mobilize ​​soldiers​, police officers and civil servants ​to help public health researchers’ contact-tracing efforts.