Nasopharyngeal and oropharyngeal swabs, and/or serology for SARS COVID-19: What are we looking for?

Governments and clinicians that were fully involved in the dramatic SARS-CoV-2 outbreak during the last few weeks in Italy (and more or less all over the world) are fiercely debating the use of methods for screening this viral infection. Thus, all countries are employing a lot of resources in order to test more and more subjects. For this purpose, there are different strategies, based on either direct or indirect tests. Among the first category, the main assays used for SARS-CoV-2 are based on a real-time reverse transcriptase polymerase chain reaction (RT-PCR). Such tests can be performed on nasopharyngeal and oropharyngeal swabs for the categories of those with symptoms and those potentially exposed. In order to integrate the molecular assays in the diagnosis of SARS-CoV-2, a wide range of serology immunoassays (IAs) have also been developed. If we want to identify “immune” people in order to let them to come back to work, serology is the best (and probably the only) approach.