Coronavirus family has caused several human illnesses, the latest caused by SARS-CoV-2, has led to COVID-19 pandemic posing serious threat to global health. A SARS-CoV-2 variant encoding a D614G mutation in the viral spike (S) protein has now become the most prevalent form of the virus worldwide, suggesting a fitness advantage for the mutant. The G614 variant is associated with higher upper respiratory tract viral load, higher infectivity, increased total S protein incorporation into the virion, reduced S1 shedding and a conformational change leading to a more ACE2- binding and fusion- competent state. However, it does not seem to be correlated to increased disease severity or escape neutralizing antibodies.