Prematurely promoting antibody tests as a screening tool all over the US will give individuals, who test positive and are not actually immune to COVID-19, a false sense of protection. PMC and Europe PMC, consistent with existing copyright protections. This short article has been cited by other articles in PMC. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the computer virus that causes the respiratory illness coronavirus disease 2019 (COVID-19) that has infected millions of people worldwide. Soon after detection of spread of SARS-CoV-2 in the United States (US), focus was on developing molecular nucleic acid detection assessments (real-time reverse transcriptase polymerase chain reaction [RT-PCR]) for early diagnosis of contamination in symptomatic patients, patients with known exposure, and patients who are at risk. Molecular screening is usually ramping up all over the US, and more than 6.5 million people have been tested by the end of April 2020.1 Different parts of the US have been hit with varying intensity. New York State has been hit hardest, with more than 300,000 confirmed cases and many more Thevetiaflavone presumed to be infected and with a prevalence of COVID-19 expected to be as high as 10% to 15%, comparable to that seen in Italy, Spain, and some parts of China.2 Serologic studies in other parts of the US that have a lower COVID-19 attack rate have shown a lower prevalence ( 1%-3%).3 With early signs of flattening of the curve, as a result FGF2 of more people adhering to social distancing and staying at home, the focus has now shifted to widespread antibody (serologic) screening of the population. Antibody assessments are blood assessments that detect antibodies or immunoglobins (Ig) that are produced as human immune response to SARS-CoV-2 contamination. A positive result suggests that the individual has potentially been exposed to SARS-CoV-2. When IgM antibodies are present, they can indicate an active or recent contamination. IgG antibodies show up later in contamination and can often indicate a past infection but does not exclude recently infected patients who can still be contagious, especially when IgM antibodies are also concurrently detected. For viral infections IgG antibodies usually persist longer than IgM antibodies and provide immunity from reinfection, but this is not known for COVID-19 yet.4 Antibody tests are being developed to detect IgG only, both IgG and IgM, or total antibodies. The Trump administration and the media have been promoting antibody assessments as a screening tool to allow individuals with positive results to get back to work and open our economy. The assumption is that the individuals with positive antibody assessments have recovered from COVID-19 (symptomatic or asymptomatic) contamination and have developed immunity to the computer virus. Furthermore, it is assumed that such individuals are thus no longer susceptible to contamination and can return to work safely without fear of getting infected or spreading the infection. However, to be used as a strong and successful screening tool, an antibody test should have a high positive predictive value (PPV), ie, positive results can be trusted as true positive with confidence. PPV is dependent on the accuracy of the test (sensitivity and specificity) and the prevalence of disease in the population and can be calculated by using the following formula: math xmlns:mml=”http://www.w3.org/1998/Math/MathML” display=”block” id=”m1″ mstyle displaystyle=”true” mtable columnalign=”left” columnspacing=”1″ mtr mtd mstyle displaystyle=”true” mrow mi mathvariant=”normal” P /mi mi mathvariant=”normal” P /mi mi mathvariant=”normal” V /mi mtext ? /mtext /mrow mrow /mrow mrow /mrow mo = /mo mfrac mrow mrow mi mathvariant=”normal” S /mi mi mathvariant=”normal” e /mi mi mathvariant=”normal” n /mi mi mathvariant=”normal” s /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” t /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” v /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” t /mi mi mathvariant=”normal” y /mi /mrow mrow mtext ? /mtext mo /mo Thevetiaflavone mtext ? /mtext /mrow mrow mi mathvariant=”normal” P /mi mi mathvariant=”normal” r /mi mi mathvariant=”normal” e /mi mi mathvariant=”normal” v /mi mi mathvariant=”normal” a /mi mi mathvariant=”normal” l /mi mi mathvariant=”normal” a /mi mi mathvariant=”normal” n /mi mi mathvariant=”normal” c /mi mi mathvariant=”normal” e /mi /mrow /mrow mrow mrow mi mathvariant=”normal” S /mi mi mathvariant=”normal” e /mi mi mathvariant=”normal” n /mi mi mathvariant=”normal” s /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” t /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” v /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” t /mi mi mathvariant=”normal” y /mi Thevetiaflavone /mrow mrow mtext ? /mtext mo /mo /mrow mrow mtext ? /mtext mi mathvariant=”normal” P /mi Thevetiaflavone mi mathvariant=”normal” r /mi mi mathvariant=”normal” e /mi mi mathvariant=”normal” v /mi mi mathvariant=”normal” a /mi mi mathvariant=”normal” l /mi mi mathvariant=”normal” a /mi mi mathvariant=”normal” n /mi mi mathvariant=”normal” c /mi mi mathvariant=”normal” e /mi /mrow mrow /mrow mo + /mo mrow /mrow mrow /mrow mrow mo ( /mo mn 1 /mn mo ? /mo mrow mi mathvariant=”normal” S /mi mi mathvariant=”normal” p /mi mi mathvariant=”normal” e /mi mi mathvariant=”normal” c /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” f /mi mspace width=”thinmathspace” /mspace mi mathvariant=”normal” i /mi mi mathvariant=”normal” c /mi mi mathvariant=”normal” i /mi mi mathvariant=”normal” t /mi mi mathvariant=”normal” y /mi /mrow mo ) /mo /mrow mrow /mrow mrow mo /mo mtext ? /mtext /mrow mrow /mrow mo stretchy=”false” ( /mo mn 1 /mn mo ? /mo mrow mi mathvariant=”normal” P /mi mi mathvariant=”normal” r /mi mi mathvariant=”normal” e /mi mi mathvariant=”normal” v /mi mi mathvariant=”normal” a /mi mi mathvariant=”normal” l /mi mi mathvariant=”normal” a /mi mi mathvariant=”normal” n /mi mi mathvariant=”normal” c /mi mi mathvariant=”normal” e /mi /mrow mo stretchy=”false” ) /mo /mrow /mfrac /mstyle /mtd /mtr /mtable /mstyle /math As of April 30, 2020, 10 antibody tests have been approved by the US Food and Drug Administration (FDA) under emergency use authorizations. Average sensitivity and specificity of FDA-approved antibody tests is 84.90% and 98.63%, respectively. The details of FDA-approved tests are shown Table 1.5 Approximately 90 antibody tests offered by various manufactures are still under FDA review but are available in the market, without established Thevetiaflavone sensitivity and specificity, being used in hospitals and clinics as a screening tool. Given variable prevalence of COVID-19 (1%-15%) in different parts of the US and differences in performance characteristics of antibody tests (FDA approved and unapproved), statistically the PPV will vary widely and can be as low as 30% to 50% in areas with low prevalence Table 2. Table 1 Manufacturers and Details of Antibody Tests Approved by.