Development and clinical application of a rapid IgM‐IgG combined antibody test for SARS‐CoV‐2 infection diagnosis

Abstract

The outbreak of the novel coronavirus disease quickly spread all over China and to more than 20 other countries. Although the virus (SARS-Cov-2) nucleic acid RT-PCR test has become the standard method for diagnosis of SARS-CoV-2 infection, these real-time PCR test kits have many limitations. In addition, high false negative rates were reported. There is an urgent need for an accurate and rapid test method to quickly identify large number of infected patients and asymptomatic carriers to prevent virus transmission and assure timely treatment of patients.We have developed a rapid and simple point-of-care lateral flow immunoassay which can detect IgM and IgG antibodies simultaneously against SARS-CoV-2 virus in human blood within 15 minutes which can detect patients at different infection stages. With this test kit, we carried out clinical studies to validate its clinical efficacy uses. The clinical detection sensitivity and specificity of this test were measured using blood samples collected from 397 PCR confirmed COVID-19 patients and 128 negative patients at 8 different clinical sites. The overall testing sensitivity was 88.66% and specificity was 90.63%. In addition, we evaluated clinical diagnosis results obtained from different types of venous and fingerstick blood samples. The results indicated great detection consistency among samples from fingerstick blood, serum and plasma of venous blood. The IgM-IgG combined assay has better utility and sensitivity compared with a single IgM or IgG test. It can be used for the rapid screening of SARS-CoV-2 carriers, symptomatic or asymptomatic, in hospitals, clinics, and test laboratories.

A model to predict SARS-CoV-2 infection based on the first three-month surveillance data in Brazil

“…The model obtained exhibited an excellent AUC in the SP/RJ dataset comparable to more complex tools, including imaging and laboratory tests. 16,17 This is impressive, considering that it is based solely on variables collected by the surveillance system.…”

Rapid and accurate identification of COVID-19 infection through machine learning based on clinical available blood test results

“…14,15 So this method can only be used as an effective supplement and auxiliary diagnosis of nucleic acid detection. 16 Until now, the quick diagnosis of COVID-19 patients in a large scale is still a major problem for global health concern. 17 Except for the laboratory-confirmed COVID-19 patients, there are a large number of suspected patients and close contacts who need to be confirmed whether they are infected or not.…”

Heat inactivation of serum interferes with the immunoanalysis of antibodies to SARS-CoV-2

“…6 The antibodies to SARS-CoV-2 are specific, sensitive, and more importantly, their detection can be much faster and simpler than RT-PCR, which allows rapid screening of suspect cases to be possible. 7 All the biological specimens for COVID-19 testing should be considered to be potentially infectious. Therefore, test must be performed by medical professionals with protective equipment in a qualified laboratory.…”