Risk of COVID-19 among Front-Line Health-Care Workers During The COVID-19 Pandemic

Objective Serologic features of severe acute respiratory syndrome coronavirus 2 （SARS-CoV-2） among front-line health-care workers during the coronavirus disease 2019（COVID-19） pandemic remain poorly characterized. It is still unclear whether they have established protective immunity. Methods The medical and administrative staff, who were equipped with different personal protective equipment（PPE） in accordance with the institutional guidelines, in a cancer center affiliated to a designated hospital for COVID-19 during the pandemic, were tested for antibodies against SARS-CoV-2 using two assay kits （Wondfo and Innovita）, employing the colloidal gold method. Nasopharyngeal swabs for all participants were also collected. Results The participants included personnel in the isolation ward area （n=18, 6.40%）, fever clinics （n=11, 3.9%）, general wards （n=221, 78.9%）, and administrative and logistic departments （n=30, 10.7%）. Most participants （n=278, 99.2%） were tested negative on both assays. One participant （0.36%） was tested weakly positive for IgG/IgM （Wondfo） and negative for IgG and IgM （Innovita）, whereas another participant （0.36%） was tested weakly positive for IgM and negative for IgG （Innovita） and IgG/IgM （Wondofo）. Both participants tested negative in the dynamic serological test were conducted later. Nucleic acid testing for all participants were negative. Conclusions The current hierarchical PPE at this cancer center was effective in protecting personnel from COVID-19. Staff did not get infection or establish protective immunity even they were exposed in high-risk environments and close contacted with infected patients. Therefore, healthcare personnel remain vulnerable and should strictly maintain personal protection.