The Chinese port at Ningbo closed operations at one of its five terminals Wednesday after a port worker tested positive for the coronavirus.

Officials’ decision to close a terminal at the world’s third-busiest port portends worsening congestion and delays. This just as the industry recovers from a month-long, 70 percent shutdown at the Port of Yantian in south China.

According to FreightWaves, operations at the Meishan Terminal in Ningbo stopped immediately upon detection of the sole case. The closure effectively restricted operational capacity at the port by 20 percent — a significant blow for a complex that sits behind only Shanghai and Singapore in throughput.

Reuters reports that some carriers have already announced that some vessels will re-route to Shanghai or simply skip Ningbo.

So far, only the Meishan Terminal has shuttered. The closure will worsen shipping delays in and out of the region. If more cases are detected and officials opt to restrict Ningbo further, a serious supply chain disruption could develop.

Scarbrough International is monitoring this story and will share news with clients and partners as it becomes available.