key: cord-288553-fez60jyn authors: Colaneri, Marta; Seminari, Elena; Piralla, Antonio; Zuccaro, Valentina; Filippo, Alessandro Di; Baldanti, Fausto; Bruno, Raffaele; Mondelli, Mario U. title: Lack of SARS-CoV-2 RNA environmental contamination in a tertiary referral hospital for infectious diseases in Northern Italy. date: 2020-03-19 journal: J Hosp Infect DOI: 10.1016/j.jhin.2020.03.018 sha: doc_id: 288553 cord_uid: fez60jyn nan The World Health Organization defined Coronavirus Disease 2019 (COVID-19) as the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a betacoronavirus belonging to the same subgenus as the severe acute respiratory syndrome Coronavirus (SARS-CoV). Human coronaviruses (HCoVs) spread in a similar fashion as Rhinoviruses, by direct contact with infected secretions or large aerosol droplets [1] . Health care workers are at increased risk of acquiring COVID-19 infection, possibly due to direct contact with the patients. Indeed, transmission of HCoVs through environmental contamination has been reported in healthcare settings [2] . Understanding which are the potentially contaminated surfaces in a healthcare environment is crucial to protect healthcare workers from this virus showing an unprecedented exponential trend with a doubling time of 3.6-4.1 days [3] . In this regard, studies suggest that surfaces and suspensions can carry HCoVs, increasing the risk of contact transmission that could lead to hospital acquired HCoVs infections [4, 5] Since February 21, 2020, when the first autochthonous case in Italy was confirmed, an overwhelming number of SARS-CoV-2 infections is continuously being detected, exceeding 8,000 cases at the time of writing. Fondazione IRCCS Policlinico San Matteo, Pavia, is a 1,300-bed tertiary teaching hospital in Northern Italy and a national SARS-CoV-2 referral center. The hospital houses 23 ICU beds and 44 Infectious Diseases (ID) beds, the latter being distributed in two floors. In the ID ward, each room has a buffer zone to allow safe donning and disposal of PPE. Healthcare workers involved in the direct care of patients use the following PPE: liquid-repelling gowns, double gloves, a class 2 filtering face-piece respirator (FFP2) and eye protection (goggles or face shield). Cleaning procedures have been standardized [7], in particular ward surfaces are cleaned with sodium hypochloride at the concentration of 1,000 ppM of free chlorine (0.1%) daily and 5,000 ppM of free chlorine (0.5%) in terminal sanitization. From February 21 to 29, 580 cases of SARS-CoV-2 were identified by the Virology laboratory, and those with interstitial pneumonia were admitted. Samples were collected on 28 th February; by that day 100% of admitted patients were COVID-19 positive with pneumonia, and were treated with C-PAP or high flux oxygen. Surfaces in areas considered virus free were swabbed to search for COVID-19 RNA. Table 1 indicates which surfaces and objects were subjected to swabbing and Fig. 1 Stability and inactivation of SARS coronavirus Environmental Contamination and Viral Shedding in MERS Patients during MERS-CoV Outbreak in South Korea Early phylogenetic estimate of the effective reproduction number of SARS-CoV-2 Survival of human coronaviruses 229E and OC43 in suspension and after drying on surfaces: A possible source of hospital-acquired infections Human coronavirus 229E remains infectious on common touch surface materials Transmission of SARS and MERS coronaviruses and influenza virus in healthcare settings: the possible role of dry surface contamination We thank nurses for collaboration.