Human coronaviruses (HCoV) were first identified in the 1960s in the noses of patients with the common cold. Two human coronaviruses are responsible for a large proportion of common colds OC43 and 229E.
Coronaviruses were given their name based on the crown-like projections on their surfaces. “Corona” in Latin means “halo” or “crown.”
Among humans, infection most often occurs during the winter months as well as early spring. It is not uncommon for a person to become ill with a cold that is caused by a coronavirus and then catch it again about four months later.
This is because coronavirus antibodies do not last for a very long time. Also, the antibodies for one strain of coronavirus may be useless against other strains.Human coronaviruses cannot be cultivated in the laboratory easily, unlike the rhinovirus, another cause of the common cold. This makes it difficult to gauge the coronavirus’ impact on national economies and public health.
Different types of human coronaviruses vary in the severity of illness they cause and how far they can spread.
There are currently seven recognized types of coronavirus that can infect humans.
Common types include:* 229E (alpha coronavirus)
* NL63 (alpha coronavirus)
* OC43 (beta coronavirus)
* HKU1 (beta coronavirus)
Rarer, more dangerous types include MERS-CoV, which causes Middle East Respiratory Syndrome (MERS), and severe acute respiratory syndrome (SARS-CoV), the coronavirus responsible for SARS. In 2019, a dangerous new strain started circulating, but it does not yet have an official name. Health authorities are currently referring to it as 2019 Novel Coronavirus (2019-nCov).