Demand in China for medical supplies like oxygenators and pulse oximeters, which measure the oxygen concentration in arterial blood, has grown exponentially in recent weeks, as the authorities concerned have optimized COVID-19 prevention and control measures to tackle the less lethal but highly contagious Omicron sub-variants.

Available stocks of various types of oxygen concentrators and oximeters made by major Chinese medical equipment manufacturers such as Yuwell Group, Lepu Medical and Edan Instruments have sold out already. To buy fresh output, consumers need to reserve in advance on e-commerce platforms such as Alibaba's Taobao, JD and Suning.com, market observers said.

Data from online retailer Suning.com showed sales of homeuse medical devices rose 214 percent month-on-month this month, while JD Health, the healthcare arm of JD, said the transaction volume of oximeters skyrocketed 61 times year-on-year in the past week alone.

Contec Medical Systems Co Ltd, a high-tech company focusing on research, manufacture and distribution of medical devices, said it has adjusted its production lines and is expanding its capacity to meet soaring demand, with the daily output of pulse oximeters alone reaching 100,000 units.

Last year, Contec's oximeter products alone generated sales revenue of 461 million yuan ($66.21 million), about 50 percent of the company's total revenue.

SysMed China Co Ltd, a Shenyang, Liaoning province-based manufacturer of oxygen concentrators, non-invasive ventilators and other respiratory rehabilitation products, said it exports medical devices to more than 100 countries and regions, and about 95 percent of its output of oxygen concentrators is usually sold abroad.

Huang Yong, general manager of SysMed China, said the company has successfully negotiated a slight delay in shipments with overseas clients, as domestic orders for its oxygen concentrators have spiraled more than 10 times.

"But strong domestic demand has already caused some chaos in the industry's supply chain, and our company cannot produce products at full swing due to a shortage of some components," he said, adding medical devices should be left for those who are really in need of them.

Yuwell Group, a prominent manufacturer of medical products in China, said the current levels of production of its oximeters and oxygenators have been normal, and it will expand its business in an appropriate way after factoring in its own advantages, development direction and strategic positioning.

In 2021, sales of Yuwell's ventilators and oxygenators were worth 2.62 billion yuan, accounting for nearly 40 percent of its total revenue. In the segment of oximeters, the company's products command over 70 percent market share on JD's online marketplaces.

Bo Wenxi, chief economist at marketing firm Interpublic Group China, said some people, fearing possible infections, tend to stock up on some medical equipment. They should, however, realize that only patients in severe or critical condition and elderly people with underlying health conditions need oxygenators and oximeters to test their blood oxygen saturation levels, he said.