Amid a nationwide seasonal flu outbreak, COVID-19 numbers are also creeping up in India, raising concerns that a new Omicron variant may be triggering the spike in coronavirus cases.
On March 12, the country reported 514 new COVID-19 cases, the highest in nearly four months, while active cases rose to 3,809. The states that are recording more coronavirus cases compared to others include Maharashtra, Kerala, Delhi, Telangana and Gujarat.
Though the overall COVID-19 test positivity rate stays at 0.5 percent for the country, some districts and states have seen a rising trajectory in the positivity rate.
The rising COVID test positivity rate in some areas also prompted the Union health ministry to shoot a letter to states on March 11, asking them to step up surveillance related to influenza-like illnesses and severe acute respiratory illnesses.
“While the COVID-19 trajectory has decreased substantially in the last few months, the gradual rise in COVID-19 test positivity rates in some States is a concerning issue that needs to be promptly addressed,” health secretary Rajesh Bhushan said in the letter.
Experts, while pointing out that hospitalisations and deaths due to COVID-19 have not gone up yet, also cautioned that India’s genomic surveillance for the viral disease is not sufficient at present, and said that the numbers need to be watched before predicting a pattern.
Eye on hospitalisation pattern
Officials in the health ministry said that surveillance of routine influenza cases shows a prevalence of viral respiratory pathogens like Influenza A (H1N1 and H3N2, among others) and adenoviruses apart from some variants of Omicron.
“Therefore, states need to be on a vigil to check if more people with respiratory illnesses are landing up in hospitals and if yes, what may be the responsible pathogen,” said an official.
Epidemiologist Naman Shah too said that slight rise in cases alone may be hard to interpret given the weaknesses of our surveillance.
Insiders in the INSACOG, India’s COVID-19 genomic surveillance consortium, maintained that the number of samples from COVID-19 patients being subjected to whole genome sequencing has gone down substantially, which may be detrimental in quickly detecting new SARS CoV2 strains triggering spikes.
Based on the limited surveillance, however, Omicron XBB is still the most dominant SARS CoV2 strain in India as of now.
Waning immunity driving numbers?
Biologist Anurag Aggarwal, who is associated with Ashoka University, underlined that there do not seem to be red flags as of now, and the rise in cases may be a result of more testing since due to a higher incidence of respiratory illnesses, more people may be getting the tests done.
“Of course, if cases keep rising or test positivity rate goes up, it would need a deeper look,” he told Moneycontrol. “We should keep in mind that the circulation of SARS CoV2 hasn’t stopped, so some ups and downs are expected.”
Infectious disease specialist Ishwar Gilada said the case pattern needs to be watched for a few weeks before an inference can be drawn. He however pointed out that a large adult population in India may now be having waning immunity against COVID-19 as the majority had completed their primary vaccination schedule in 2021 and have not taken booster doses.
“I strongly recommend COVID-19 booster dose and annual shots against influenza for the elderly and those with underlying co-morbidities,” Dr Gilada said.
He also suggested that Indian vaccine makers should be encouraged to develop flu vaccines in order to reduce their costs for local consumption.
According to virologist Dr Shahid Jameel, who is associated with the University of Oxford, the rising cases may be due to the winter blip when respiratory viruses show increased infections.
“The reasons are mainly that people stay indoors and are also subject to high air pollution that further compromises the upper and lower respiratory tracts,” he said.
He also underlined that the key figure is the positivity rate, which though increased, is still low.
“High levels of primary series of vaccination (2 doses) will protect from severe disease,” said Jameel. “But policymakers should seriously consider ways of increasing boosters. India has the options and must use them”.