As the delta variant spreads on the mainland, most Chinese ports are now requiring a Covid test for all crew, with vessels forced to remain at anchor until negative results are confirmed, and requiring ships to quarantine for 14-28 days if they previously berthed in India or changed crew within 14 days of arriving.

That spells further delays, further price increases and, according to Splash, shipping will need to start to make contingency plans should China - the world's most important nation for shipping movements - emerge as another pandemic epicenter.

The delta variant has broken through the country's virus defences, which are some of the strictest in the world, and reached nearly half of China's 32 provinces in just two weeks. While the overall number of infections — more than 360 so far — is still lower than Covid resurgences elsewhere, the wide spread indicates that the variant is moving quickly with many millions of Chinese now in lockdown.

"For freight markets, the implications include delays at ports as authorities screen crews of incoming vessels and a hit to China's oil demand if widespread lockdowns are imposed," a report from Braemar ACM pointed out this week.

When a Covid-19 outbreak was detected at Yantian Port in late May, operations at the key southern Chinese export hub were slashed by 70% for most of June. Similar disruptions are in the cards in the coming weeks, while shipyards are also likely to see their delivery schedules come under pressure if any wider lockdown measures are taken.

"As long as lockdowns remain confined to China, the impact on freight markets is likely to be muted, especially in the case of wet and dry freight. The container market seems most vulnerable if we see more severe disruptions to manufactured products supply chains," commented Plamen Natzkoff, senior trade expert at VesselsValue. On the potential tanker ramifications, Natzkoff said: "An immediate impact of a lockdown in China is reduced population mobility which would have a direct impact on demand for transportation fuels, potentially impacting negatively the tanker market."