The Emergence of Human Pathogenic Coronaviruses: Lectins as Antivirals for SARS-CoV-2

Human coronaviruses (HCoV) are common viruses and known to be associated with respiratory diseases, including pneumonia. Currently, seven human coronaviruses have been identified and known to cause upper and lower respiratory infections as well as nosocomial viral infections in humans. The bats, palm civets, and camels are identified as the reservoir of human coronaviruses. In 2002-2003, the emergence of SARS-CoV resulted in an outbreak and led towards the more awareness and importance of scientific research and medical urgency.

The recently identified SARS-CoV-2 was identified from the seafood market of the city Wuhan, China, in December 2019 and caused a global pandemic. This virus has now spread to more than 213 countries. This is the third highly pathogenic human coronavirus after SARS and MERS-CoV. The coronaviruses have RNA as genetic material and are known to have frequent recombination and mutations in their genome, which lead to the emergence and re-emergence of new virus strains and isolates with novel properties and extended hosts. The genetic mutations and suitable environmental conditions result in the emergence and re-emergence of pathogenic coronaviruses and cause a serious issue to human health and the economy globally. Lectins are the ubiquitous group of proteins that bind to glycosylated molecules.

The plant lectins are known to have significant antiviral activities against coronaviruses. Additionally, the plant lectins can be used as potential therapeutics against bacteria, fungus, yeast, and protozoa. In this review, we have discussed the current status of human pathogenic coronavirus emergence and the use of plant lectins as antivirals against SARS-CoV-2.