Effects of regular testing as a sort of Covid-19 filter, by identifying, isolating and thus filtering out currently infected persons, using antigenic tests among healthcare workers in three hospitals in the South of Italy

Abstract

The use of antigen tests is proposed as a substitute for the molecular test in some conditions and the Italian Regions are preparing for massive provision. This method has been introduced and tested in the local health authority ASL BT - Puglia (Italy) and then integrated with the regional health surveillance protocol for health workers thanks to the preliminary results. In the Puglia Region there has been an Integrated Health and Safety Management System SGSL (SiRGISL) since pre-COVID times, which has standardized procedures and protocols as regards to Integrated Health and Safety for the prevention of hospital worker risks. Where the method was first tested, a screening test was introduced on 2,500 health workers operating in the three hospitals of the BT district, weekly. The nasopharyngeal swabs were carried out by the coordinators (workers safety representatives in Puglia Region SGSL), the swabs were sent to the PoCT (Point of Care Testing) analysis laboratory with immediate reading of the antigen test following by molecular test method confirmation. The study was performed in a Puglia district with high virus circulation. About 12 thousand swabs were performed, mainly in the period, which identified 192 cases of positivity to SARS CoV2 among asymptomatic operators not detected symptomatic by the usually temperature control method at the hospital entrance. During the third week a peak of cases (79) with a subsequent decline was revealed, otherwise the infection trend of the population district maintained a constant growth. Early identification and removal of asymptomatic hospital workers, by means of frequent use of rapid tests, acts as a filter and reduces the chances of contagion by cutting the chains at the origin. During a time featured by high viral circulation, the amount and the speed of the tests should be privileged over more accurate methods, difficult to manage with a very high demand. In Puglia Region, the presence of Integrated Health and Safety Management System (SiRGISL) makes the organizational structures efficiently adaptable to the rapid change of the pandemic framework by choosing suitable technologies and methods in order to anticipate the change of the pandemic curve instead of following it. Asymptomatic subjects detecting is a major problem in the management of epidemics even in controlled environments such as hospitals.