BHOPAL: Doctors treating Covid-19 cases in Indore say a more virulent strain may be wreaking havoc in the city, which has emerged as the coronavirus hotspot in Madhya Pradesh They say samples from Indore, where Covid-19 has killed 57 people, will be sent to the Pune-based National Institute of Virology (NIV) to confirm their apprehensions of the strain being deadlier than in other parts of the country."We have a feeling the strain is definitely more virulent in Indore belt. We have discussed this with the NIV and will be sending samples for them to compare by extraction of virus genome, Dean of Government Mahatma Gandhi Memorial (MGM) Medical College Jyoti Bindal told PTI."There are also other factors also for the high fatality rate, like patients turning up at the hospitals late," she said. "In Indore belt, the testing is confined to coronavirus detection only, and not its type, another doctor said.Jitendra Bhargava, director of the state government- run School of Excellence in Pulmonary Medicine, also shared Bindals concern, saying the high mortality rate in Indore needs to be investigated through viral culture and RNA extraction.It is also true that the mortality rate is high in patients who had comorbidities (presence of additional conditions along with the primary condition) like cardiac and renal problems or diabetes and hypertension besides other immunity-compromising conditions, he said."The novel coronavirus is posing a big challenge due to multiple strains. This will make the development of a universal vaccine much more difficult," he said.