“It really is death by a thousand cuts,” said John Evans, managing director of Tractus Asia, a company that has 20 years’ experience helping firms move to China, but which over the past two has had more enquiries from businesses looking to leave. “This is a black swan event and I don’t think we’ve seen anything like it in recent history, in terms of the economic and supply chain impact in China and across the globe.”

Australian company B&R Enclosures, which makes units for protecting industrial equipment, said the outbreak has cut it off from suppliers and delayed the return of its migrant workers from their hometowns, following the extended Lunar New Year break. Only 15 per cent of the migrant workers had come back, said B&R China general manager Marko Dimitrijevic said, although with most of the company's office workers having returned, he expects a full workforce by next week.

“All supply chains are having trouble, it’s very serious,” he said.

“While work has officially started last week, most employees were still quarantined or just on their way back due to lack of transport,” Dimitrijevic said.

Based on the Baidu Migration Index, analysts at Nomura estimated that only 25.6 per cent of migrant workers had returned to work across 15 sample cities by February 19, compared to 101.3 per cent a year earlier.

Refing Enterprise Group, one of China’s three largest producers of piping for plumbing, drainage and gas fields, is facing severe losses across its nationwide factories, which are all in various states of idleness.

“February is usually boom season for us, where we take orders from many of our customers,” said Yang, speaking from the company headquarters in Foshan. “But this year we have only taken about 20 million yuan (US$2.85 million) worth of new orders versus 400 million yuan (US$57 million) last year. We have to assume the demand is still there, but it is delayed.”

Rifeng’s Foshan plant caters for its export market and has managed to get a few containers out of the country since last week. But in the meantime the firm is routing domestic production from Hubei, Xian and Tianjin through the Guangdong plant, which it hopes to ratchet up to 80 per cent capacity next week, Yang said.

“China is so big, that every city can have vastly different policies,” said Walter Ruigu, Beijing-based managing director at Camal Group, which connects Chinese manufacturers of steel, equipment for construction and mining, and industrial chemicals with buyers in Africa.

“The distance from the epicentre and local government actions have been crucial. In the north and northeast activity has resumed this week. We have seen some movement in Dalian Port and Qingdao Port, but for now the issue has been finding the logistics to get to that point,” Ruigu said.

There have been reports of cargo ships being marooned at sea, with ports in countries with strict coronavirus quarantine rules such as Australia, Singapore and the United States not permitting shipping personnel to enter their ports if they have been in China over the past 14 days.

Andy Lane, Asia director at shipping analysis firm Sea Intelligence, said that Australia had seized two ships from China, belonging to Singaporean line PIL and Chinese line COSCO, with the crew now undergoing a 14-day quarantine period before they can unload their cargo.

While 43 sailings from Chinese ports to the US West Coast were cancelled before the Lunar New Year holiday in anticipation of the seasonal slowdown, “ subsequent to the holidays starting and we would say directly related to the virus, a further 19 sailings were cancelled”, Lane said.

A further two cargo sailings were cancelled from China to the US East Coast, five from Asian ports to North Europe and five from Asia to Mediterranean ports, he added.

A survey by the American Chamber of Commerce in Shanghai released this week found that almost 80 per cent of respondents in the manufacturing sector were unable to staff their production lines.

An overwhelming 92 per cent of the 100 Australian and global businesses surveyed by the Australian Chamber of Commerce Shanghai last week, meanwhile, said the outbreak would have a negative impact on their revenue in the first quarter of this year, with more than half saying it could dent their top-line earnings by more than 20 per cent.

Hetin Shah, the president of supply chain management company MES Inc, said that his US Fortune 500 clients “do not want anything to do with China right now”, with the supply chain risks deemed to be too severe.

The company, out of its Ningbo office, sources goods from Chinese suppliers to be exported to multinational clients in the US, Europe and Mexico.

After a few weeks of standstill, MES is this week hoping to put a container with goods for export from Anhui province on a boat in Shanghai, and load two containers on a ship at port in Ningbo. However, even as the logjam of goods starts moving, Shah said the scars will remain.

“Our key suppliers are terrified. Even workers within the province aren’t willing to go out and go to work, people are really scared,” he said, referring to fears of becoming infected with the virus. “People are still choosing to stay at home.”