The US may have had more than 6.4 million COVID-19 cases by Apr 18 instead of the 721,000 officially tallied by then, according to a new probability analysis in Nature Communications.
The authors of the study said the model accounts for a lack of testing of asymptomatic and mild cases from Feb 28 to Apr 18, the first 6 weeks of the pandemic."Accounting for uncertainty, the number of infections during this period was 3 to 20 times higher than the number of confirmed cases.
86% (simulation interval: 64–99%) of this difference is due to incomplete testing, while 14% (0.3–36%) is due to imperfect test accuracy," they said.The authors said their findings confirm other studies that looked at seroprevalence in communities hit hard by the virus,