"Shanghai is the first megacity in China to become an aging society. One important significance of adhering to the ‘dynamic zero-COVID’ policy is to prevent mass infections among elderly people," remarked Qu Jieming, Chairman of the Respiratory Diseases Branch of Chinese Medical Association and Party Secretary of Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine. Epidemic prevention and control in Shanghai has now entered its most critical stage, with the number of new infections still running high. At the same time, the number of cured patients discharged from hospital and people released from medical observation has also reached new highs. “As patient “turnover” at shelter hospitals quickens, Shanghai has also sped up its efforts to ensure that “all those in need are tested, isolated, hospitalized or treated”, which lays a solid foundation for realizing zero COVID.

The Omicron variant has shown clear changes from its predecessors, the most prominent of which is its higher transmission power. In epidemiology, the transmission power of a virus is commonly measured by R0, which is the reproductive number of the virus. In 2020, the R0 of the original COVID-19 strain was estimated to be about 2.5, while that of the Delta strain is about 5-6. The global academic community now predicts that Omicron is 3-4 times as contagious as Delta. 

The high transmission power of Omicron poses unprecedented challenges to epidemic prevention and control. Conceived based on respect for science and reflecting the underlying patterns of the virus, "dynamic zero-COVID" is a policy that most suits China's reality. "Essentially, 'dynamic zero-COVID' is not equivalent to zero COVID infection in a region. Rather, it means that once a case of infection breaks out, the outbreak can be brought under control as quickly as possible, without causing any large-scale spread," explained Qu Jieming, "The requirement that ‘all those in need are tested, isolated, hospitalized or treated’ is a specific measure that is scientific and effective to find the infected people and block the transmission chain as soon as possible.” 

In the view of Qu Jieming, efforts to implement this specific measure embody three in-depth considerations behind adherence to the "dynamic zero-COVID" policy.

Firstly, without "dynamic zero-COVID", a high transmission power will enable the virus to spread fast in communities, neighborhoods and towns, as well as among the vast natural population at large. If not blocked, fast-growing cases in some regions will easily overflow to other regions on a large scale. 

Secondly, despite the mild symptoms, when the base number of infected people increases, those patients with such underlying diseases as coronary heart disease, heart failure, renal insufficiency, chronic bronchitis and emphysema, as well as patients with tumor and other low-immunity functions can easily develop into severe or critical cases due to their COVID-aggravated their underlying diseases. The proportion of those infected with COVID-19 and the likelihood of their development into severe or critical cases will both increase. 

Taking the example of Ruijin Hospital North which is a designated hospital to treat COVID patients: 15% of the patients admitted there are over the age of 60 and there are also 53 hemodialysis patients. Qu Jieming said that during his recent daily consultations, he found that almost all severe patients at the hospital were elderly people, or even patients over 85. In the intensive care unit of the hospital, there are also cases where patients with mild infections and ordinary patients suffer from visibly aggravated underlying diseases after they are infected with COVID-19.

Thirdly, due to the constraints of age, underlying diseases and other factors, the most vulnerable population is also the population with the lowest COVID vaccination rate. Once the base number of the infected population increases within a short period of time, the proportion of severe cases will also rise, which will not only easily lead to a run on medical resources, but also cause the risk of infecting other hospitalized patients, thus resulting in irreparable consequences.

"Based on the above considerations, 'dynamic zero-COVID' is no doubt a necessary and scientific policy for controlling the base number of infected people and curb the further spread of the pandemic," said Qu Jieming. Medical staff should always keep in mind that the original intention of adhering to the "dynamic zero-COVID" policy is to truly put the people and their lives first. "We will continue to concentrate our advantageous resources on containing the spread of the pandemic as soon as possible with the 'dynamic zero-COVID' policy, and strive to achieve win-win for both epidemic prevention and control and economic and social development."



Author: Tang Wenjia, Wenhui Daily