text: Prevalence of SARS CoV 2 RNA on inanimate surfaces a systematic review and meta analysis Coronavirus disease COVID 19 is a respiratory disease affecting many people and able to be transmitted through direct and perhaps indirect contact Direct contact transmission mediated by aerosols or droplets is widely demonstrated whereas indirect transmission is only supported by collateral evidence such as virus persistence on inanimate surfaces and data from other similar viruses The present systematic review aims to estimate SARS CoV 2 prevalence on inanimate surfaces identifying risk levels according to surface characteristics Data were obtained from studies in published papers collected from two databases PubMed and Embase with the last search on 1 September 2020 Included studies had to be papers in English had to deal with coronavirus and had to consider inanimate surfaces in real settings Studies were coded according to our assessment of the risk that the investigated surfaces could be contaminated by SARS CoV 2 A meta analysis and a metaregression were carried out to quantify virus RNA prevalence and to identify important factors driving differences among studies Thirty nine out of forty retrieved paper reported studies carried out in healthcare settings on the prevalence of virus RNA five studies carry out also analyses through cell culture and six tested the viability of isolated viruses Overall prevalences of SARS CoV 2 RNA on high medium and low risk surfaces were 0 22 CI sub 95 sub 0 152 0 296 0 04 CI sub 95 sub 0 007 0 090 and 0 00 CI sub 95 sub 0 00 0 019 respectively The duration surfaces were exposed to virus sources patients was the main factor explaining differences in prevalence 