Introduction: History of Coronavirus Disease Pandemic

Kapoor, Indu; Prabhakar, Hemanshu; Mahajan, Charu

Coronaviruses are group of ribonucleic acid [RNA] viruses that broadly infect vertebrates including humans, birds, bats, snakes, mice, and other wild animals [1]. To our interest, human coronaviruses are divided into four subgroups: alpha, beta, gamma, and delta. There are seven strains of coronavirus that may infect humans. The common human strains that produce mild symptoms include 229E [alpha], NL63 [alpha], OC43 [beta], and HKU1 [beta]. In humans, the common sign and symptoms include cough, sore throat, fever, muscle ache, and difficulty in breathing. Some patients even may present with uncommon symptoms like anosmia, chest pain, and stroke. The severity of these symptoms can vary from very mild to very lethal ones like, Middle East respiratory syndrome [MERS], severe acute respiratory syndrome [SARS], and coronavirus disease [COVID-19].