Translational, prospective / retrospective, non-profit, non-pharmacological study, with cohort characteristics.

The study consists of two parts: the first to study epidemiological aspects of the spread of the disease and the second one to identify infection-related genetic factors.

The outbreak of COVID-19 infections is spreading in Italy with unprecedented severity characteristics. In this context, it is essential to collect data relating to the epidemiology of the disease, to outline further useful tools for diagnosis and to define the correct use of rapid molecular and / or serological tests in the surveillance of high-risk subjects (cancer patients and healthcare operators), in order to identify any new disease control strategies, crucial to reduce the transmission and to outline specific guidelines for cancer patients healthcare management. It is also necessary to identify the factors that determine the evolution of the viral genome over time in the various geographical areas and also the potential susceptibility markers in the different types of affected subjects (symptomatic, mildly symptomatic and asymptomatic).

For epidemiologic analysis:

Inclusion Criteria:

• Age > 18 years
• asymptomatic
• One of the following three conditions: • Healthy subjects who have had contact with COVID-19 positive patients • Healthcare workers • oncological patients candidates for cytotoxic chemotherapy at myeloablative doses (such as transplants) or treated with immune-check point inhibitors.
• informed consent to the study and processing of data

Exclusion Criteria:

• presence of symptoms for COronaVIrus Disease 19 (COVID-19) (fever > 37.5 °, cough, shortness of breath)

For analysis of viral/host genetic factors involved in susceptibility/resistance to infection, samples from patients with confirmed diagnosis of COVID-19, residual from diagnostic procedures will be analyzed. All samples for genetic analysis will be anonymized.

For epidemiologic analysis, asymptomatic population 350 health workers / healthy subjects at risk of infection and 50 cancer patients candidates for immunosuppressive therapies will be enrolled.

For analysis of genetic variability of virus and host factors impacting on susceptibility to infection: samples from about 100 SARS-CoV-2 positive patients (sintomatic, paucisintomatic or asymptomatic), retained at Pievesestina Laboratory after diagnostic procedure, will be analyzed. All samples for genetic analysis will be anonymized.