The first time Huang Lipeng came across a “pulse oximeter” was on Douyin, China’s version of TikTok, last week. The 30-year-old IT engineer from Zhuhai, in southern China’s Guangdong province, quickly bought an oximeter for his family after watching videos that said people with diabetes should pay special attention to their blood oxygen levels. His 60-year-old father has severe diabetes while his mother has had surgery for uterine cancer. Omicron BA.5 subvariant may cause more damage – not less: study But he hesitated to buy an oxygen generator and then the price spiked – doubling to 1,580 yuan (US$227) a week later before quickly going out of stock. Since China abruptly scrapped its strict zero-Covid policy , Covid-19 has swept through the population, with hospitals and medical resources so overwhelmed that residents have realised they might not be able to access critical healthcare should they suddenly need it. Stories of untold numbers of elderly patients dying because of a lack of emergency medical care have scared many into stocking up on home medical equipment, buying drugs through the black market, or even taking antibiotics without a doctor’s prescription. Antivirals such as Pfizer’s Paxlovid and Azvudine from Chinese firm Genuine Biotech have become hot topics on social media as people try to find ways to buy them. The medical scarcities have also been a boon for middlemen who can source generic drugs from India. Fearing they might develop pneumonia, some patients with persistent Covid-19 symptoms have even resorted to treating themselves when faced with queuing for hours at a fever clinic. “I gave myself azithromycin [an antibiotic used to treat bacterial infections] for three days after one week of coughing. It’s very likely doctors will just prescribe azithromycin for pneumonia if I go to hospital … so I just started [treating] myself,” said Yu Qian, 42, whose entire Beijing household contracted Covid-19 two weeks ago. “Call it antibiotic abuse, but I think it’s acceptable given the circumstances. My cough eased anyway.” Residents have also become increasingly concerned about conditions like “silent hypoxia” (low oxygen levels) in elderly patients, prompting people like Huang to buy monitoring devices and prepare oxygen support for seniors at home. Online discussions by social media influencers have also fuelled concerns. Last week, Fan Deng, a former CCTV anchor shared on social media how his father showed no obvious shortness of breath when, in fact, his oxygen saturation level had been dangerously low. A subsequent test with a pulse oximeter revealed the problem, and the father was sent to hospital before dying a few days later. Shanghai epidemiologist Zhang Wenhong said in a speech that the elderly tend to be unaware of the symptoms of hypoxia, as they do not sense chest tightness or breathing difficulties. As China reopens borders, which countries are imposing Covid travel curbs? Huang Wenxiang, head of the geriatric department at a Chongqing hospital, said patients with “silent hypoxia” accounted for about 5 per cent of severe Covid-19 cases, adding they may quickly progress to life-threatening acute respiratory failure. “The blood oxygen levels of elderly people after Covid-19 infections should be closely monitored through pulse oximeters,” he told state media outlet Chongqing Daily on Monday. The latest State Council guidelines on how to manage Covid-19 at home have also directed local governments to ensure they have adequate supplies of oximeters. The sudden public interest in “silent hypoxia” has led to a scramble for oximeters and oxygen generators, and several e-commerce platforms have seen sales of the devices soar. Data from the e-commerce analysis platform Whale Staff shows that sales of various brands of oximeters doubled this month from November. Some buyers have been waiting for weeks to get the medical devices. In Guangzhou, a restaurant owner who bought an oxygen generator in April, sold it to his neighbour who was “in a dire situation” for the same price he paid for it. The neighbour had not been able to find any devices online and could not get help from hospitals, said the man, who requested anonymity. Yuyue, a medical equipment company based in the eastern province of Jiangsu, said it sold more than 200,000 oxygen generators and 20,000 oximeters this month on the online shopping platform Taobao. Travellers at Hong Kong airport surprised by end of post-arrival Covid tests Thermometers, oximeters and oxygen generators were all out of stock in the Omron online stores, which are run by a Japanese electronic healthcare manufacturer. Wait times for new stocks were “uncertain,” a customer service staff member told the Post. Online customer service inquiries were busy with several long waits, when the Post checked. Xin Miao, a saleswoman who joined a community group-buying platform on WeChat on Saturday, said oximeters were the bestsellers. “I found and decided to join the platform when I was trying to get oximeters for my family members, as I kept seeing media reports on the harm of ‘silent hypoxia’,” she said. “Most of my customers were also buying them for the elderly members of their families.” The 40 oximeters she put on the platform for 40 yuan each were sold out by Tuesday. None had been available for purchase since.