Manufacturing firms in east China's Shanghai have started to resume production despite the strict COVID-19 control measures in the city.

China recently launched the first batch of 666 Shanghai firms that are eligible for resumption, many of which are in the manufacturing sector, such as carmakers, chip producers and pharmaceutical firms.

One of the firms is Quanta Shanghai Manufacturing City, a laptop manufacturer based in Shanghai's Songjiang District that resumed production last Friday.

Staff members are required to live at the factory and take daily antigen tests, the company said, and meal times are staggered in order to prevent possible cross infection. 

Though only 800 out of its 40,000 staff have returned to work, the company stressed the urgency of resuming production.

"Of course production cannot be fully resumed, but resumption in different phases is giving confidence to employees and also our clients," said Walter Lee, associate vice president of Quanta Shanghai Manufacturing City. "This will also prevent our clients from shifting orders to other countries, which is not good to our company and also to the country's economy."

Quanta is not the only firm that has resumed production. Shanghai-based carmaker SAIC has its Lingang assembly factory up and running, and 4,000 staff are expected to return to the factory.

Chen Peifeng, director of SAIC's assembly plant, said whether its suppliers can resume production is also crucial to the firm's assembly business.

"We are also studying the resumption situation of our suppliers – whether they have any COVID-19 cases in the factory and whether they can do closed-off production," said Chen.

Also, following a three-week suspension, Tesla's Shanghai plant resumed production on Tuesday, with 8,000 employees returning to work, according to Shanghai Media Group.

Nearly 40 percent of the first batch of companies that are preparing to resume operations in Shanghai are auto-related firms, followed by pharmaceutical firms and chemical firms.

Such urgent restarts stem from the importance of the city's manufacturing sector to its economic growth. In 2021, the city's industrial added value accounted for nearly a quarter of the city's GDP.