RT-PCR:
All samples were subjected to RNA extraction with Qiagen Viral Nucleic Acid Kit (QIAcub HT) according to the manufacturer’s instructions. RT-PCR was used to detect the presence of SARS-CoV2 using the kits (Molbiol, Germany) provided by WHO targeting the E region for screening and RNA dependent RNA polymerase for confirmation. Invitrogen Superscript III One-Step RT-PCR System with Platinum Taq DNA Polymerase was used for PCR. For each reaction, 15 µl reaction mix, 1 µl RT enzyme, 0.5 µl primer, probe mix and 3.5 µl PCR grade water were added to 5 µl RNA template. Cycling conditions for amplification of E and RdRP genes were 50°C for 30 min, 95°C for 2 min, followed by 45 cycles of 95°C for 10 sec and 60°C for 30 sec. A cycle threshold value of <36 Ct was defined as a positive test result.