The world's largest shipping port by cargo tonnage has shut down one of its key terminals following a confirmed case of Covid-19, putting further strain on the global shipping industry and disrupting supply chains.

The news came as container shipping rates from China and Southeast Asia to the east coast of the United States hit a record high of more than US$20,600 per 20-foot equivalent unit (TEU) – the standard measure for freight container volume – according to the Freightos Baltic global container freight index.

On Wednesday, a 34-year-old employee at the Meishan Terminal of China's Ningbo-Zhoushan Port tested positive for the coronavirus despite being fully inoculated with two doses of the Sinovac vaccine. It was an asymptomatic infection.

Port authorities quickly locked down the Meishan area – including the terminal and bonded warehouse – and suspended its operations indefinitely, according to a statement released by the local government in Ningbo, Zhejiang province.

The disruption in Ningbo could exacerbate existing delays in global shipping, as the impact on productivity at the port is likely to have a knock-on effect, Nair said.

"While the congestion is rampant around major global ports, currently all attention is on China," he said, "because its ports are so large in scale, and exports starting from there would impact the overall global supply chain."

"The fact that ships remain delayed, and now Covid variant outbreaks in major Chinese manufacturing hubs are on the rise, indicates that there may be far-reaching downstream consequences going into Black Friday and the holiday shopping seasons," said Josh Brazil, vice-president of marketing at Project44, referring to the last Friday in November that is considered the official start to the US Christmas shopping season.