HCoV-OC43 is definitely a common cold virus, and very unpleasant to those without immunity, and since it is in the same genus as covid-19 we can expect covid-19 to behave very similarly with regard to immunity, so far the evidence supports that:
"Along with HCoV-229E, -NL63 and -HKU1,
HCoV-OC43 is responsible for up to 30% of all common colds in adults;
"Although most of the replication of HCoV-OC43 occurs in the epithelial cells of the upper respiratory tract, this virus is unique in its ability to tolerate mutations and even cause infection in the brain.
"In addition to its most notable effects on the upper respiratory tract and possible neuronal infiltration, a 2001 outbreak of HCoV-OC43 in Normandy, France found that this virus can also cause a wide range of digestive problems to occur.
"More specifically, this outbreak found that up to 57% of patients with HCoV-OC43 experienced vomiting, diarrhea, and abdominal pain.
"In addition to upper respiratory tract effects, patients with HCoV-OC43 in this French study also experienced several lower respiratory tract symptoms, of which included bronchitis, bronchiolitis, and pneumonia in 17%, 1-%, and 6.7% of all patients.
To further understand infection by SARS-CoV-2, researchers have reevaluated the pathogenesis associated with coronaviruses that have already been identified.
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