The world may have to endure another three years of intermittent lockdowns, breathing through face masks, and regular reminders to social distance, according to a new pandemic outcome simulation by a team of Chinese researchers.

Scientists from Shanghai Normal University and Lanzhou University predicted that the pandemic has not yet reached a global peak, according to a report obtained by Sixth Tone. The number of infected would likely peak in March next year, with 80 million confirmed diagnoses and possibly several million more people untested.

The COVID-19 virus’ high contagiousness and relatively low death rate means it would not simply disappear like its cousin the SARS virus did years ago, after spreading to over 30 countries and regions. Even if there’s a safe and effective vaccine rollout next year, the pandemic is likely to persist through the second half of 2024. There will be enormous demand to inoculate as many of the world’s 7.8 billion people as possible, and making headway will take time.

The team’s attempt to simulate a global pandemic scenario is likely the first in China, Huang Jianping, an atmospheric scientist at Lanzhou University, told Sixth Tone. Other models, he added, tend to be national or regional in scope. Before COVID-19, Huang and his team specialized in climate-related simulations.

“For weather forecasts, we always do models at the global scale, so we decided to accept the challenge (to simulate the pandemic),” he said.

Huang’s model incorporates several climate factors — including temperature and humidity — that may impact the spread of the virus. Moreover, they used nitrogen dioxide, a pollutant emitted mainly by automobiles, as an indicator of lockdown strength across the globe. If people aren’t staying home even when orders to do so are in effect, local nitrogen dioxide levels are likely to be higher.

While there are many approaches to predicting outcome scenarios, such as using disease data and climate models, only time can reveal the projection’s accuracy, Cheng Jin, a math professor at Fudan University in Shanghai, told Sixth Tone. Cheng, who did not participate in Huang’s model, said pandemic simulations that account for vaccines may be less precise, because the current data about them — their effectiveness, duration of protection, and more — is lacking.

“Of course, a simulation isn’t a crystal ball,” Wen Jiahong, the head of Shanghai Normal University’s disaster risk assessment center and a collaborator on Huang’s model, told Sixth Tone. “It’s unrealistic to expect simulated predictions to be extremely accurate, especially for things that are going to happen years in the future. A simulation shows a trend, where things are headed.”

Cheng and his team in Shanghai have also attempted to project a global outcome scenario, but the lack of quarantine controls in some virus hotbeds like the U.S. and the U.K. has made predicting an endpoint almost impossible. Without effective measures to curb the spread, he said, the pandemic curve’s trajectory could spiral “out of control.”

Editor: David Paulk.

(Header image: A man takes a selfie on a ferry in Wuhan, Hubei province, April 2020. Zhong Ruijun/Southern Metropolis Daily/People Visual)