Detection of Anti-COVID-19 Antibody Levels in an Hospital Population

The Coronavirus identified in Wuhan, China, for the first time in late 2019 is a new viral
strain that has never previously been identified in humans. It has been called SARS-CoV-2 and
the respiratory disease that causes COVID-19. SARS-CoV-2 infection in health professionals
has represented and continues to represent a significant criticality both for the risk of
spreading the disease and for the organizational aspects that follow.

Currently the gold standard for the non-invasive diagnosis of COVID-19 is the detection of
the viral genome by RT-PCR. However, despite the high specificity, this technique has a low
sensitivity and can produce false negative samples. Furthermore, detection of the viral
genome is indicative of active infection and fails to identify subjects previously exposed to
the virus who have passed the infection asymptomatically. Serological tests can detect the
presence of anti-SARS-CoV-2 antibodies in blood or serum samples and, depending on the type
of antibody detected, identify the subjects in the active phase of the infection and after
the resolution of the infection, the whose diagnosis was not made by performing a swab.

We will evaluate the actual spread of the SARS-CoV-2 virus within the hospital personnel of
Humanitas through the monitoring of the levels of IgG antibodies. Moreover, viral load will
be measured by RT-PCR of nasopharyngeal swabs in the subgroup positive to IgG antibodies.
Secondary endpoints are: visualize the trend of the antibody value at 3, 6 and 12 months;
correlation between the antibody titer in test positive subjects and the viral load of the
nasopharyngeal swab; identification of predictive variables of susceptibility to viral
SARS-CoV2 infection.