US may have seen over 28,000 coronavirus infections by March 1, far higher than 23 reported cases: Study
In the early stages of the outbreak, the world's attention was on China. But back home, the virus seems to have quietly gained a foothold in five major US cities, without setting off the alarm.
By March 1, the virus may have already infected about 28,000 people in New York City, San Francisco, Seattle, Chicago and Boston, according to a new modeling study. At that time, these cities had only confirmed 23 patients with the disease, suggesting the US was far behind in detecting the virus.
"The disease spread under the radar," Alessandro Vespignani, director of the Network Science Institute, who led the study to trace the footsteps of the virus, told CNN.
In early February, the virus was spreading across multiple cities. During this time, the US authorities were debating the need to shut schools and the possibility of working from home. “Meanwhile, in the background, you have this silent chain of transmission of thousands of people,” Vespignani, director of the Network Science Institute at Northeastern University in Boston, who led the research team, told The New York Times.
The model predicts the number of early infections in the country, including those that went undetected. But there are problems with modeling studies: They often do not make accurate predictions because they predict the outcomes of the real-world conditions.
Still, other experts say these findings are consistent with other analyses. Dr Adriana Heguy, director of the Genome Technology Center at New York University’s Grossman School of Medicine, told NYT: “We weren’t testing, and if you’re not testing you don’t know. The new estimates suggesting that thousands of infections were spreading silently in the first months of the year don’t seem surprising at all."
Dr Hugey also conducted a study to understand how the virus entered New York. Their analysis showed that most infections in the state came from multiple locations in Europe, rather than directly from China.
By late February, the virus began to take hold in Italy, and flights may have brought more cases into the US. “Knowing the number of flights coming into New York from Italy, it was like watching a horrible train wreck in slow motion,” Dr Hugey, told NYT.
Supporting the new findings is a report from Santa Clara County. According to health officials, the US may have witnessed its first COVID-19 death on February 6, at least three weeks before the first confirmed death in the country.
Commenting on the new report, Dr Sara Cody, the county's public health director, told CNN: "The virus was circulating perhaps fairly widely in our county."
Taking these findings into account, experts warn that easing restrictions such as social distancing too early could prove disastrous. The study comes as the US is looking to reopen. The country has enough tests to support states looking to reopen under phase one of President Donald Trump's guidelines, Stephen Hahn, the commissioner for the US Food and Drug Administration, said.
"We are confident that we have enough tests for phase one of the reopening America plan but we do acknowledge the fact that we need to keep the pressure on developing more tests, getting more tests out there," Hahn said during CNN's coronavirus town hall.