Abstract
The Huanan market harbored many of the early COVID-19 cases in 2019 and is a key element to understanding the origin of the pandemic. Whether the initial animal-to-human transmission did occur at this market is still debated. Here we do not examine how SARS-CoV-2 virus was introduced at the market, but focus on how early cases may have been infected at the market. Based on available evidence, we suggest that several early infections at the Huanan market may have occurred via human-to-human transmission in closed spaces such as canteens, Mahjong rooms or toilets. We advocate for further studies to investigate this hypothesis.