Dog coronavirus jumps to humans, with a protein shift

Millions of dog owners beware! Mask mandates, quarantine and lockdown are coming for your dogs! 

Well there is possibly a chicken and egg question: Did humans infect dogs first?

Are we dealing with zoonosis (animal to human) or zooanthroponosis (human to anima) transmission?

(Caution: Satire) 😄

"Cornell researchers have identified a shift that occurs in canine coronavirus that points to a possible pattern of change found in other coronaviruses and which may provide clues to how they transmit to humans from animals. ...
A new canine coronavirus was first identified in two Malaysian human patients who developed pneumonia in 2017-18. ...
Now, a team led by Cornell and Temple University researchers has identified a pattern that occurs in a terminus of the canine coronavirus spike protein – the area of the virus that facilitates entry into a host cell: The virus shifts from infecting both the intestines and respiratory system of the animal host to infecting only the respiratory system in a human host. ..."

From the abstract:

"A canine coronavirus (CCoV) has now been reported from two independent human samples from Malaysia (respiratory, collected in 2017–2018; CCoV-HuPn-2018) and Haiti (urine, collected in 2017); these two viruses were nearly genetically identical. In an effort to identify any novel adaptations associated with this apparent shift in tropism we carried out detailed evolutionary analyses of the spike gene of this virus in the context of related Alphacoronavirus 1 species. The spike 0-domain retains homology to CCoV2b (enteric infections) and Transmissible Gastroenteritis Virus (TGEV; enteric and respiratory). This domain is subject to relaxed selection pressure and an increased rate of molecular evolution. It contains unique amino acid substitutions, including within a region important for sialic acid binding and pathogenesis in TGEV. Overall, the spike gene is extensively recombinant, with a feline coronavirus type II strain serving a prominent role in the recombinant history of the virus. Molecular divergence time for a segment of the gene where temporal signal could be determined, was estimated at around 60 years ago. We hypothesize that the virus had an enteric origin, but that it may be losing that particular tropism, possibly because of mutations in the sialic acid binding region of the spike 0-domain."

Dog coronavirus jumps to humans, with a protein shift | Cornell Chronicle

Recent Zoonotic Spillover and Tropism Shift of a Canine Coronavirus Is Associated with Relaxed Selection and Putative Loss of Function in NTD Subdomain of Spike Protein (open access)