Can the novel coronavirus be transmitted via RNAs without protein capsids?

Abstract

The existing knowledge is insufficient to explain some infection events of SARS-CoV-2, and new ideas about the transmission modes may be needed. The present study proposes that the RNAs of this virus might be infectious and that the transmission of these RNAs might be one route of transmission of SARS-CoV-2. I speculate that SARS-CoV-2 RNAs are infectious based on the following rationale and offer a putative mechanism: RNA is the most important biomolecule of the novel coronavirus for expression and replication, free RNA strands of SARS-CoV-2 have the potential to remain suspended in the air and retain their biological activity, and some exogenous RNAs can enter the host cell after contact. Further studies are needed in order to verify this hypothesis. It is worthwhile to compare the effects of SARS-CoV-2 components (e.g., virus particles, positive RNA strands, negative RNA strands, and virus proteins) with symptoms to study the mechanism of asymptomatic infection. If additional detection results show that the proportion of RNA in the environment is higher than the proportion of RNA in the novel coronavirus particles, this would suggest the potential presence of free RNA genomes of SARS-CoV-2 in the environment. Research on the temporal and spatial distribution of infectious SARS-CoV-2 RNA strands is necessary. The nucleic acid test of SARS-CoV-2 should target not only positive RNA strands but also negative RNA strands. For medical purposes, studying environmental RNAs (eRNAs) is important. I believe that further investigation of the infection capabilities of viral RNAs will yield useful information.