Researchers have found two new mutations in coronavirus samples from Amravati and Yavatmal districts of eastern Maharashtra which can escape neutralizing antibodies. However, in none of the samples for which genome sequencing was done, the UK, South African or Brazilian strains of the virus were found, he added.
Yavatmal and Amravati are among the districts in the state which have shown a considerable increase in new cases in the last one week. Genome sequencing was done for 24 samples — four each from Amravati, Yavatmal and Satara and 12 from Pune — said Dr Rajesh Karyekarte, Head of Department of Microbiology at the state-run B J Medical College and Sassoon General Hospital in Pune.
"We were asked by the state government to conduct genome sequencing of samples. The D614G strain which is prevalent was found in all the samples," he said.
But in Amravati, Yavatmal and Satara, they also came across different mutations, Dr Karyekarte said.
"In Amravati, we came across a mutation named E484K in all the four samples. When we inquired if all samples belonged to one family, we were told they were taken from different locations, so the conclusion was that it was a common mutation," he said.
The character of the strain found in Amravati is that it escapes neutralizing antibodies, he said.
"In a nutshell, even if there are neutralizing antibodies in the human body, the particular mutation escapes or saves itself from these antibodies," Dr Karyekarte said.
In Yavatmal samples, they found a mutation named N440K, which is commonly seen in Andhra Pradesh, he said.
"It was also found in a case of re-infection in Delhi. This mutation too can escape the neutralizing antibodies and cause re-infection," he added.
In the Satara sample, a new mutation named V911I was found but the researchers could not find significant scientific references about this mutation in published journals, he said. All these strains are of A2 type of coronavirus, which is common in India.
Maharashtra on Friday reported more than 6,000 new coronavirus infections in a single day for the first time after more than three months, indicating a worsening pandemic situation. As many as 6,112 fresh cases were reported during the day, most of them coming from Akola, Pune and Mumbai divisions, said an official of the state health department.
The state had reported more than 6,000 cases in a single day on October 30 earlier, and the numbers had dropped steadily thereafter. With 6,112 cases on Friday, the caseload in the state rose to 20,87,632, while 44 fatalities took the death toll to 51,713, the official said.
Of 44 deaths, 19 occurred in the last 48 hours, 10 in the last week while 15 had taken place before that, he said.
Mumbai city and surrounding region is the biggest contributor to COVID-19 cases. But since February 12, Akola city and district and Amravati city and district have recorded a noticeable spike.
Mumbai city reported 823 new cases and five deaths, taking the tally of cases to 3,17,310 and the death toll to 11,437. Mumbai division's tally is 7,10,425 and the death toll is 19,743.
Dr Murlidhar Tambe, Dean of B J Medical College and Sassoon General Hospital, said these "small curves" (spurts in infections) are happening due to lax behaviour as gatherings, weddings and various functions are happening and no physical distancing is being followed. They have received six samples for genome sequencing from Akola where a spike has been witnessed, he said.