Background and objective:
Despite the development of effective vaccinations, the SARS-CoV-2 disease continues to have a high impact on society, due to the presence of variant of concerns of which a probable route is the indirect one. It is therefore essential to identify the possible presence of the virus on surfaces, evaluate its environmental persistence and possible ways of elimination. Our aim was to identify the presence of SARS-CoV-RNA on environmental surfaces in non-COVID and COVID wards and its elimination after sanitization with hydrogen peroxide and silver ions or with nebulization of active chlorine, both pre-sanitization and post-sanitization methods.

Materials and methods:
The sampling was performed with rayon swabs pre-moistened with sterile water on a surface of 25 cm2 and processed within 24 hours of sampling with the LAMP technique (ICGENE Enbiotech S.r.l.®). Statistical analysis was performed with R software.

Results:
114 surfaces were sampled (50% belonged to the healthcare area, 38% was represented by devices and 12% to the remaining area). 67.6% of the samples were carried out on surfaces belonging to CoViD-19 wards. The sampled surfaces were sanitized with a) hydrogen peroxide and silver ions in 23.5% of the cases b) with active chlorine in 76.5% of the cases. They were positive in 44% after nebulization with active chlorine and 0% after nebulization with hydrogen peroxide and silver ions with the finding of a pvalue less than 0.01.

Conclusions:
SARS-CoV-2 RNA detected by RT-PCR can be found on surfaces from hours to days, depending on the environment and surface type. Despite the finding of this contamination, there aren’t specific studies that have directly demonstrated indirect transmission. It remains essential to identify the most appropriate sanitization method to avoid possible transmissions through indirect contact. Nebulization with hydrogen peroxide and silver ions is a valid alternative to classic sanitization.