In 2008, I wrote a blog piece entitled “Who do you bind to, my lovely?”, about a couple of papers on SARS-CoV – the coronavirus that causes severe acute respiratory syndrome. I closed that piece with the following:
“Adding fuel to the speculative fire is another paper in the same issue: this reports that there is evidence of a recombinant origin for SL-CoVs, and there is probably “…an uncharacterized SLCoV lineage that is phylogenetically closer to S[ARS]CoVs than any of the currently sampled bat SLCoVs.”
So let’s all just wait for the next one, shall we?”
…in connection with the fact that horseshoe bat coronaviruses were VERY similar to SARS-CoV, but bound to different receptors. And we had to wait five years, but heeeeeere we are… these folk may well have found the missing virus(es) that are directly transmissible from bats to humans:
Nature (2013) doi:10.1038/nature12711
Here we report whole-genome sequences of two novel bat coronaviruses from Chinese horseshoe bats (family: Rhinolophidae) in Yunnan, China: RsSHC014 and Rs3367. These viruses are far [! – my comment; the last ones were pretty close…] more closely related to SARS-CoV than any previously identified bat coronaviruses, particularly in the receptor binding domain of the spike protein. Most importantly, we report the first recorded isolation of a live SL-CoV (bat SL-CoV-WIV1) from bat faecal samples in Vero E6 cells, which has typical coronavirus morphology, 99.9% sequence identity to Rs3367 and uses ACE2 from humans, civets and Chinese horseshoe bats for cell entry. Preliminary in vitro testing indicates that WIV1 also has a broad species tropism. Our results provide the strongest evidence to date that Chinese horseshoe bats are natural reservoirs of SARS-CoV, and that intermediate hosts may not be necessary for direct human infection by some bat SL-CoVs. They also highlight the importance of pathogen-discovery programs targeting high-risk wildlife groups in emerging disease hotspots as a strategy for pandemic preparedness.
So – I told you so…B-)