New Delhi, Jan 6 : The Central government on Wednesday said that a total of 71 persons have been detected with the new 'more transmissible' UK coronavirus mutant strain. They are kept in physical isolation in health facilities. According the Health Ministry, all these persons have been kept in single room isolation in designated Health Care facilities by respective state governments. 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. On December 29, a total of six UK returnees were found to be positive with the new variant genome. These were the first cases to be reported by the country that has the second highest number of cases after the United States. The tracing and testing was initiated after British government announced that a newly identified strain of the virus was found in their population which is up to 70 per cent more transmissible. Notably, the new UK variant has already been reported by Denmark, Netherlands, Australia, Italy, Sweden, France, Spain, Switzerland, Germany, Canada, Japan, Lebanon and Singapore. From November 25 to December 23 midnight, about 33,000 passengers disembarked at various Indian airports from UK. All these passengers are being tracked and subjected by States and UTs to RT-PCR tests. The Union Health Ministry further stated that 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 labs. /IANS