China might face over 1.5 million COVID-19 deaths if it dropped its dynamic zero-COVID policy without any safeguards, such as high vaccination rates and timely and effective epidemic prevention measures, according to a paper released in Nature Medicine.

　　In the paper, authors developed an age-structured stochastic compartmental susceptible-latent-infectious-removed-susceptible (SLIRS) model of SARS-CoV-2 transmission, calibrated on the initial growth phase of the 2022 Omicron outbreak in Shanghai, to project COVID-19 burden (i.e., number of cases, patients requiring hospitalization and intensive care, and deaths) under hypothetical mitigation scenarios.

　　The model also considers age-specific vaccine coverage data, vaccine efficacy against different clinical endpoints, waning of immunity, different antiviral therapies, and non-pharmaceutical interventions.

　　They found that the level of immunity, induced by the March 2022 vaccination campaign, would be insufficient to prevent an Omicron wave that would result in exceeding critical care capacity, with a projected intensive care unit peak demand of 15.6-times the existing capacity and causing approximately 1.55 million deaths.

　　"The availability of vaccines and antiviral drugs offer an opportunity to move away from zero -COVID. I can't think what there is now to wait for," said Ben Cowling, an epidemiologist at Hong Kong University familiar with the study.

　　Meanwhile, WHO announced on May 12 that over a million Americans died and more than two million died in Europe of COVID-19, while the number in China is less than 15,650 by the end of May 16.

　　China has always put the people and their lives first. This is exactly the core value of the dynamic zero-COVID policy. That is also the reason why China had a relatively low number of fatalities from COVID -19 compared with other lying-down (non-feasance) countries. China's epidemic prevention policy is not zero-sum game, but for protecting people's lives as well as fostering a sound economic environment.

　　Maria Van Kerkhove, the WHO's technical lead on COVID -19, said at press conference that, "We live in an interconnected world. And so while some countries may have been able to end the emergency phase of this pandemic, we don't see that in all countries worldwide. So we need to continue to fight this at a global level."

　　In addition to the templates mentioned in this paper, authors also analyzed three measures to reduce the burden of COVID-19 disease.

　　The first is to continue rolling out vaccinations, including booster shots and increasing vaccination for unvaccinated people aged over 60.

　　The second is to take drugs against COVID-19.

　　The third is to adopt stricter non-pharmaceutical interventions (NPI), such as wearing masks.

　　None of these three measures alone could reduce mortality to flu season levels or prevent excessive demand for intensive care. But authors also found that a combination of these three measures, including increased vaccination of the elderly and vulnerable people, more use of antiviral drugs and NPI, could reduce mortality rates and prevent a run on health care resources.