A systematic review of human coronaviruses survival on environmental surfaces

Abstract

The current pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has led people to implement preventive measures, including surface disinfection and use of alcohol-based hand gel, in order to avoid viral transmission via fomites. However, the role of surface transmission is still debated. The present systematic review aims to summarize all the evidence on surface survival of coronaviruses infecting humans. The analysis of 18 studies showed the longest coronavirus survival time is 28 days at room temperature (RT) on different surfaces: polymer banknotes, vinyl, steel, glass, and paper banknotes. Concerning SARS-CoV-2 human infection from contaminated surfaces, dangerous viral load on surfaces for up to 21 days was determined on polymer banknotes, steel, glass and paper banknotes. For viruses other than SARS-CoV-2, the longest period of survival was 14 days, recorded on glass. Environmental conditions can affect virus survival, and indeed, low temperatures and low humidity support prolonged survival of viruses on contaminated surfaces independently of surface type. Furthermore, it has been shown that exposure to sunlight significantly reduces the risk of surface transmission. Although studies are increasingly investigating the topic of coronavirus survival, it is difficult to compare them, given the methodology differences. For this reason, it is advisable to define a reference working protocol for virus survival trials, but, as an immediate measure, there is also a need for further investigations of coronavirus survival on surfaces.

Keywords: COVID-19; Health care; Inanimate surfaces; Persistence; Sunlight.

Graphical abstract

Fig. 1

Flow diagram reporting the number of retrieved studies from two databases (PUBMED and EMBASE) and after title/abstract (T/A) screening. After full-text screening, 18 studies were included and 12 studies were excluded for the provided reasons.

Fig. 2

Influence of initial virus titer (TCID₅₀) on coronavirus survival on plastic (a), metal (b) and glass (c) surfaces at room temperature (20–25 °C). Survival <1 day and aerosol-contaminated surfaces are not included. Black arrows mean virus was still detected at the last experimental time point.