Emergence and expansion of highly infectious spike:D614G mutant SARS-CoV-2 in central India

Abstract

COVID 19 has emerged as global pandemic with largest damage to the economy and human psyche. The genomic signature deciphered during the ongoing pandemic period is valuable to understand the virus evolutionary patterns and spread across the globe. Increased availability of genome information of circulating strain in our country will enable to generate selective details in virulent and non virulent markers to prophylaxis and therapeutic interventions. The first case of SARS CoV-2 was detected in Chambal region of Madhya Pradesh state in mid of March 2020 followed by multiple introduction events and expansion of COVID-19 cases within 3 months in this region. We analyzed around 5000 COVID -19 suspected samples referred to Defence Research and Development Establishment, Gwalior, Madhya Pradesh. A total of 136 cases were found positive over a span of three months period this includes virus introduction to region and further spread. Whole genome sequences employing Oxford nanopore technology were deciphered for 26 SARS-CoV-2 circulating in 10 different districts in Madhya Pradesh State of India. The region witnessed index cases with multiple travel history responsible for introduction of COVID-19 followed by remarkable expansion of virus. The genome wide substitutions including in important viral proteins were observed. The detailed phylogenetic analysis revealed the circulating SARS-CoV-2 clustered in multiple clades A2a, A4 and B. The cluster wise segregation was observed suggesting multiple introduction links and evolution of virus in the region. This is the first comprehensive details of whole genome sequence analysis from central India region, which will add genome wide knowledge towards diagnostic and therapeutic interventions.