From the beginning of the pandemic caused by SARS-CoV-2, most events with massive participants have been canceled due to being considered high-risk events for the SARS-CoV-2 transmission. It has been detected that asymptomatic people infected by SARS-CoV-2, are playing an important role in the contagious in these kinds of events. The economic losses arising from the closure of these activities, mainly those related to culture and musical performances are around 2.5 billion euros a Catalonia, and a considerable loss of jobs in this sector.

Developing strategies of cribrate of infected people by SARS-CoV-2 asymptomatic or not diagnosticated and with a potential transmission of the virus is the key to perform cultural, sport, etc. massive events with all the security. The objective is to exclude infected people with a a high potential of transmission.

It is needed to use versatile tests for this objective, so the test must have a high sensibility to detect infected people, the test has to be easy to manipulate without requiring a high technology of the laboratory hospitals, neither prolongated to obtain a result and that has a low cost. The rapid SARS-CoV-2 antigen screening tests are best suited for this purpose.

On 27th March, a musical concert will be performed at Palau St Jordi (Barcelona) with 5000 attendees and with all the SARS-COV-2 safety measures by the "Secretary General of Health of the Generalitat de Catalunya" a (mandatory wearing a mask during the event, restricted outdoor areas of bar and smoking enhanced ventilation of the whole indoor area and avoiding queues.). This study wants to assess the incidence of SARS-CoV-2 infection reported to the health system among the attendees of this commercial concert during the 14 days following the event, also it will be evaluated the clinical evolution of the possible infections during the concert.

From the beginning of the pandemic caused by SARS-CoV-2, most events with massive participants have been canceled due to being considered high-risk events for the SARS-CoV-2 transmission. It has been detected that asymptomatic people infected by SARS-CoV-2, are playing an important role in the contagious in these kinds of events. The economic losses arising from the closure of these activities, mainly those related to culture and musical performances are around 2.5 billion euros a Catalonia, and a considerable loss of jobs in this sector.

Developing strategies of cribrate of infected people by SARS-CoV-2 asymptomatic or not diagnosticated and with a potential transmission of the virus is the key to perform cultural, sport, etc. massive events with all the security. The objective is to exclude infected people with a a high potential of transmission.

It is needed to use versatile tests for this objective, so the test must have a high sensibility to detect infected people, the test has to be easy to manipulate without requiring a high technology of the laboratory hospitals, neither prolongated to obtain a result and that has a low cost. The rapid SARS-CoV-2 antigen screening tests are best suited for this purpose. These tests have shown a sensitivity close to 99% to detect infectious people who have a high viral load of SARS-CoV-2. No viral isolation has been demonstrated in any culture of samples of patients infected with SARS-CoV-2 with a Ct threshold (cycle threshold) in the test RT-PCR greater than 30, which is considered to delimit the transmitting potential of the infected

On 27th March, a musical concert will be performed at Palau St Jordi (Barcelona) with 5000 attendees and with all the SARS-COV-2 safety measures by the Secretaria General de Salut de la Generalitat de Catalunya (mandatory wearing a mask during the event, restricted outdoor areas of bar and smoking enhanced ventilation of the whole indoor area and avoiding queues.). This study wants to assess the incidence of SARS-CoV-2 infection reported to the health system among the attendees of this commercial concert during the 14 days following the event, also it will be evaluated the clinical evolution of the possible infections during the concert.

Inclusion Criteria:

• Adults (> 18 years and under 65) attending the commercial music event scheduled at the Palau Sant Jordi
• Sign informed consent, including an authorization for the collection of data from the electronic health system of the Catalan System of Health on the notification of COVID-19 infection during the 14 days following the event or authorization to be contacted by telephone by the medical team, if necessary, for complete information on SARS-CoV-2 infection.

Exclusion Criteria:

• Minors (<18 years)

All the commercial concert attendees, that are major of age (>18 years old) and who have signed the informed consent to access their Medical records 14 days after the commercial concert.