BA.2.75 may lead to spike in cases but severe disease ruled out

Nagpur: The growing dominance of Omicron lineage BA.2.75 is likely to cause a surge in Covid cases but the trend from metro cities indicates it may not cause severe disease in large number of patients.
Ahead of the festive season from next week, the genome sequencing results by Neeri lab regarding BA.2.75 had caused an alarm, as it has delta-like mutations and is a fitter variant. The lab detected around eight different variants of BA.2 lineage, the presence of only BA.2.75 has been found among symptomatic cases.
Dr Rajesh Karyakarte, state coordinator for genome sequencing, said the variant was found in around 75% cases in Mumbai and Pune but rate of hospitalisation, oxygen demand and deaths have remained low as per the early preliminary study carried out at BJ Government Medical College, Pune.
Karyakarte said good vaccination coverage is helping prevent severe disease. “The variant is likely replacing all other lineages. It is highly transmissible and capable of symptomatic infection but mild,” he said.
Dr Karyakarte added that all INSACOG laboratories in Maharashtra, including CSIR-Neeri, Nagpur, are actively following BA.2.75 and other variants of Omicron.
“This virus shall select a variant out of it which will cause mild infection. All parasites generally want to keep multiplying without killing the host. It is difficult to say how it will evolve further but so far it is moving towards milder form,” a scientist said.
Infectious disease specialist Dr Nitin Shinde said he is hardly seeing any Covid patients.
Infectious disease specialist Dr Ashwini Tayade too said, “We are not getting severe disease in normal host. Hopefully we get pan-variant vaccine soon.”
Pulmonologist Dr Ravindra Sarnaik said the analyses of BA.2.75 relies on open data sharing from scientists in India, and is showing remarkable evolution of SARS-CoV-2 with new variants emerging and spreading rapidly making continued global genomic surveillance essential. “If we look at frequency data, we see sustained logistic growth of BA.2.75 in India, it is clearly displacing BA.5. This can perhaps be seen at the moment despite BA.2.75 becoming predominant, there has not been a coincident increase in total cases.”
Dr Sarnaik added that several possible sub-lineages of BA.2.75 with R346T, L452R, and one with R346T and F486S reported in India, have a higher growth rate per day are likely to have higher immune escape ability. “As the virus generates fitter variants, one expects it to become increasingly fit. The ‘winning’ variant will be the one that happens to collect the right mutations for its survival,” he said.