ESTIMATING PREVALENCE AND TIME COURSE OF SARS-CoV-2 BASED ON NEW HOSPITAL ADMISSIONS AND PCR TESTS:Data posted in the COVID 19 tracking website for RT-PCR (PCR) results and hospital admissions are used to estimate the prevalence of the SARS-CoV-2 pandemic in the United States (1). Hospital admissions mitigate positive sampling bias in PCR tests due to their initially limited test numbers and application as a diagnostic, instead of a surveying tool. As of July 31, the United States' cumulative recovered population is estimated at 47% or 155 million. The remaining susceptible population is 53%, or 47% excepting the 6% infectious population. The estimated mortality rate of the cumulative recovered population is 0.09% death per case. New (Preprint)

<sec> <title>BACKGROUND</title> Serological testing for SARS-CoV-2 antibodies showed a lack of response in close to 50% of formerly afflicted patients. In addition, antibodies were found to be transient, and concentration index to disease severity. These findings made this classical method for the estimation of the recovered population from COVID-19 of limited value. The method presented on this paper relying on % RT-PCR testing and controlling for sampling bias with new hospital admission data provides an effective alternative for estimation of the extent and time course of the SARS-CoV-2 epidemic. </sec> <sec> <title>OBJECTIVE</title> The method presented on this paper relying on % RT-PCR testing and controlling for sampling bias with new hospital admission data provides an effective alternative for estimation of the extent and time course of the SARS-CoV-2 epidemic. </sec> <sec> <title>METHODS</title> Daily results for %RT-PCR, Total Test Results, Hospitalized Currently, Hospitalized Cumulative available at COVID-19 Tracking Project are used to estimate mitigation of sampling bias of RT-PCR results and daily Hospital Admissions. Since at high daily testing levels and low % positives RT-PCR evidence of sampling bias disappears, it is correlated to daily Hospital Admissions and this correlate value used to mitigate the % RT-PCR findings where sampling bias is present. This information is used to estimate time course of the infection. Knowing that the disease lasts for an average of 20 days allows the integration of the time course values to obtain cumulative recovered population. </sec> <sec> <title>RESULTS</title> Prevalence and time course of the SARS-CoV-2 pandemic in the United States are estimated. The recovered population amounts to 47%. The states of the eastern seaboard, as exemplified by New York and Massachusetts, display a sudden early onslaught of the pandemic. While California, Texas, and Florida lagged. Mortality rate is twice higher in the eastern seaboard states compared to the entire nation and the other presented states. Given the large number of the convalescent population mortality is about 0.09% nationwide. </sec> <sec> <title>CONCLUSIONS</title> Novel approach to estimating time course and prevalence shows that the recovered population is much larger, and consequently, mortality rate (0.09%) about a factor of 10 lower than currently recognized. </sec>