Their close contacts have also been put under quarantine. Comprehensive contact tracing has been initiated for co-travellers, family contacts and others. Genome sequencing on other specimens is going on, the ministry said. The situation is under careful watch and regular advice is being provided to the states for enhanced surveillance, containment, testing and dispatch of samples to INSACOG labs. Of the 73 cases, the mutated UK strain was detected in eight samples at National Centre for Disease Control (NCDC), New Delhi, in 20 at the Institute of Genomics and Integrative Biology (IGIB), Delhi, in one at National Institute of Biomedical Genomics (NIBMG), Kalyani (near Kolkata), in 30 at the National Institute of Virology in Pune, in three at the Centre for Cellular and Molecular Biology (CCMB) in Hyderabad and 11 were sequenced at the National Institute of Mental Health and Neuro Sciences Hospital (NIMHANS) Bengaluru.