Researchers have found two new mutations in coronavirus samples from Amravati and Yavatmal districts of eastern Maharashtra which can escape neutralizing antibodies, a senior official said on Thursday.
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 districts 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 here.
"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 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 Thursday reported over 5,000 new cases after a gap of 75 days.
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.