Transmission modes of severe acute respiratory syndrome coronavirus 2 and implications on infection control: a review.

Ong, Sean Wei Xiang; Coleman, Kristen K; Chia, Po Ying; Thoon, Koh Cheng; Pada, Surinder; Venkatachalam, Indumathi; Fisher, Dale; Tan, Yian Kim; Tan, Boon Huan; Ng, Oon Tek; Ang, Brenda Sze Peng; Leo, Yee-Sin; Wong, Michelle Su Yen; Marimuthu, Kalisvar

The complete picture of transmission modes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unknown. This review summarises the available evidence of its transmission modes, our preliminary research findings and implications on infection control policy, and outlines future research directions. Environmental contamination has been reported in hospital settings occupied by infected patients, and is higher in the first week of illness. Transmission via environmental surfaces or fomites is likely, but decontamination protocols are effective in minimising this risk. The extent of airborne transmission is also unclear. While several studies have detected SARS-CoV-2 RNA in air samples, none has isolated viable virus in culture. Transmission likely lies on a spectrum between droplet to airborne transmission depending on patient, disease and environmental factors. Singapore's current personal protective equipment and isolation protocols are sufficient to manage this risk.