China could see more than 1.5 million deaths from a wave of Omicron infections without Covid-19 controls and the use of antiviral therapies, a new study has forecast. A model by Chinese and US researchers suggested that, given China’s vaccine efficacy and coverage, an unchecked outbreak that began with 20 cases of Omicron in March could “generate a tsunami of Covid-19 cases” between May and July. Such an outbreak is projected to cause 112 million symptomatic cases, or 80 cases per 1,000 people, with 2.7 million of them requiring treatment in intensive care. They estimated that unvaccinated people aged over 60 would account for three quarters (74.7 per cent) of the deaths, considering 52 million people in this age group were not fully vaccinated as of mid-March. They said in the best-case scenario where all symptomatic cases are treated with oral antiviral drug Paxlovid, which has been approved for use in China , intensive care admissions and deaths could both be reduced by nearly 89 per cent. To bring the peak occupancy of intensive care units below the national capacity and the death toll to a level comparable to the annual death count of seasonal influenza in China at 88,000, the researchers said the vaccine uptake in the elderly should reach 97 per cent while more than half of symptomatic infections should be treated with antiviral therapies. “In the long term, improving ventilation, strengthening critical care capacity, and the development of new highly efficacious vaccines with long-term immune persistence would be key priorities,” the team said. WHO says coronavirus pandemic killed nearly 15 million people The researchers from the school of public health at Fudan University in Shanghai and Indiana University in the United States, and the US medical research agency National Institutes of Health, published their findings in the peer-reviewed journal Nature Medicine on Tuesday. China is facing its worst Covid-19 outbreak since it contained the initial outbreak in Wuhan in 2020, with most cases in Shanghai. The researchers used a mathematical model to simulate a hypothetical Omicron wave in China based on data from the Shanghai outbreak. “Should the Omicron outbreak continue unabated, despite a primary vaccination coverage of more than 90 per cent and homologous booster vaccination [boosting with the same vaccine] coverage of more than 40 per cent as of March 2022, we project that the Chinese healthcare system will be overwhelmed with a considerable shortage of ICUs,” they wrote. They estimated that the peak demand of 1 million intensive care beds would be almost 16 times the existing total of 64,000 beds, with a shortage lasting 44 days. China’s mass vaccination campaign has relied heavily on domestically developed shots from Sinopharm and Sinovac. Both vaccines give some protection against severe illness, hospitalisation and death from the Omicron variant despite declines in protective antibodies, according to an assessment by the World Health Organization in January, but have lower efficacy rates than some other vaccines made abroad. Separately, three Shanghai-based health experts said the city’s “life-saving efforts” against Omicron “have shown very promising results,” with new infections dropping to less than 5,000 cases in early May compared with a peak of 27,700 in mid-April, in a letter published in medical journal The Lancet on Friday. On Tuesday, the city reported 3,014 coronavirus cases and saw total infections dropping for the 17th consecutive day. Stop Shanghai’s Covid-prevention excesses, academics urge in online appeal The trio, including prominent epidemiologist Zhang Wenhong, said the vaccination rate in people over 60 remained low at 62 per cent despite an overall coverage of more than 90 per cent for the 25 million residents in Shanghai, adding that only five per cent of people who died with or from Covid-19 were vaccinated. They said if control measures such as mass testing, quarantine and lockdown had not been taken, the number of deaths and serious illnesses “could be high among the older people without vaccination” – pointing to the example of Hong Kong, which recorded the world’s highest per capita death toll at the height of its last outbreak. “The strict and comprehensive pandemic control strategies in Shanghai are therefore actually to reduce the number of people infected and to provide early diagnosis and appropriate treatment for severe Covid-19 so that the case fatality rate can be minimised, and to buy time for full vaccination coverage,” they said.