First isolation of SARS-CoV-2 from clinical samples in India

• Published in: Indian journal of medical research (New Delhi, India : 1994) India : 1994), 2020-02, Vol.151 (2), p.244-250
• Main Authors: Sarkale, Prasad, Patil, Savita, Yadav, Pragya, Nyayanit, Dimpal, Sapkal, Gajanan, Baradkar, Shrikant, Lakra, Rajen, Shete-Aich, Anita, Prasad, Sharda, Basu, Atanu, Dar, Lalit, Vipat, Veena, Giri, Sidhartha, Potdar, Varsha, Choudhary, Manohar, Praharaj, Ira, Jain, Amita, Malhotra, Bharati, Gawande, Pranita, Kalele, Kaumudi, Gupta, Nivedita, Cherian, Sarah, Abraham, Priya
• Format: Article
• Language: English
• Subjects: Cell culture; Coronaviruses; COVID-19; Genomes; Health aspects; Infections; Morphology; Mutation; Proteins; RNA polymerase; Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Testing laboratories; Viruses
• ISSN: 0971-5916
• DOI: 10.4103/ijmr.IJMR_1029_20

The designated COVID-19 testing laboratories of Virus Research Diagnostic Laboratory network (All India Institute of Medical Sciences, New Delhi; Sawai Man Singh Medical College, Jaipur; and King George's Medical University, Lucknow) referred the specimens (throat swab/nasal swab, oropharyngeal swab/sputum) to the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV), Pune, after screening for envelope (E) gene by real-time RT-PCR was done[6]. From each well of cell culture plate, on the third post-infection day (PID-3) of passage-1 (P-1), 50 μl of supernatant was taken and tested for SARS-CoV-2 using real-time RT-PCR for E and RNA-dependent RNA polymerase (RdRp) (2) genes as described earlier[7],[8]. Virus replication was confirmed using real-time RT-PCR with RNA extracted from the cell culture medium on PID-3. The number of virus copies in the isolates at P-1 in Vero CCL-81 cells ranged from 5.18×10[7] to 8.12×10[8] copy/ml and increased 1-26 fold to a range of 1.69×10[8] to 6.77×10[9] in the cell culture supernatants at P-2 [Table 1].