Around April 12 last year, India was reporting less than 1,000 new cases of Covid-19 a day. A year on, India on Wednesday notched up 7,830 new cases, according to a government update, a fairly high surge not seen in nearly a year.
But those numbers are no cause for panic, say virologists and medical experts.
More than three years since the outbreak of the Covid-19 pandemic in late 2019 and early 2020 upended the world, it is time to move on to “living with the virus”.
“There is nothing we can do except wear masks when there is a surge,” said Dr Gagandeep Kang, virologist and professor at the department of gastrointestinal sciences, Christian Medical College, Vellore.
Doctors and epidemiologists have reiterated advice about Covid-19 being seasonal, but what does that mean for life going forward?
Uncertain pattern, new variants
According to Kang, the Sars-CoV-2 virus is only three years old and while it has become endemic, it has not yet become seasonal. Seasonal viruses follow a specific pattern and cause increased infections in particular weather conditions.
For instance, dengue and malaria cases increase during the monsoon while the H1N1 virus, which causes swine flu, spikes during winters.
“It is too early to define a pattern for this virus,” said Kang. “It will take a few years for it to settle down into a pattern.”
Globally, there has been a rise in the recombinant lineage of the virus, which is a new mutated lineage formed when a person is infected by two variants simultaneously.
The recombinant lineage, called XBB, has driven an increase in Covid-19 cases in many countries. This lineage is derived from the Omicron variant lineage that was first reported by South Africa in 2021 and had led to a third wave of the pandemic in early 2022.
In India, data from the Indian Sars-Cov-2 Genomics Consortium, a network of laboratories studying the coronavirus mutation, shows that a further sub-branch of XBB, called XBB.1.16, has been observed in parts of the country. This sub-branch accounts for 38.2% of infections, the consortium said in a bulletin released at the end of March.
India’s active caseload, as on Wednesday, stood at 40,215 cases. The country is recording over 7,000 new cases every day, up from around 1,500 cases a fortnight before. The positivity rate increased from 1.33% to 3.65% in the same period, indicating a rise in viral circulation.
But the consortium said there was no indication of any increased severity of illness associated with the variants in circulation, compared to the Omicron lineage.
Co-existing safely
Epidemiologist Dr Chandrakant Lahariya said the focus should now be to co-exist safely with the virus. “Our approach should be to avoid a severe outcome because of any pathogen,” said Lahariya. “As a public health expert, I would try and protect vulnerable populations.”
Considering that Covid-19 surges will recur intermittently, Lahariya said the elderly and those with comorbidities in the 18-59 year age bracket should assess their risk of developing a severe infection.
“They must be careful during surge cycles and high transmission periods,” Lahariya said, advising masking in crowded places and keeping existing illnesses in check. “An immune system gets worn out by fighting other illnesses, and when coronavirus infects, it is too tired to fight back,” said Lahariya.
What about vaccines?
While flu vaccines will help prevent seasonal influenza, Covid-19 vaccines and booster doses are unlikely to provide long-term protection. “By the time a variant-specific Covid vaccine can be created, a new variant would have replaced all other variants,” Lahariya said.
According to Kang, data on the current mRNA vaccines used in Western countries shows that booster doses provide limited protection – only up to a few months. “There is no India-specific data on booster doses for vaccines used for the Indian population,” said Kang.
From a public health perspective, experts say the entire population may not need booster doses and that it may not be wise for the government to invest in additional vaccine doses on a large scale. But booster shots could be considered for immunocompromised patients such as transplant cases or cancer patients.
Respiratory etiquette
Lahariya said that washing hands after coughing or sneezing must be inculcated. “Emerging viruses are a challenge, and we need to learn social respiratory etiquette,” he said.
A cough produces about 3,000 droplets while a sneeze produces over 13 times more – about 40,000 droplets. Since Sar-CoV-2 is a highly transmissible virus, the coughing or sneezing without precautions can lead to the rapid transmission of Covid-19.
A study published in the American Journal of Respiratory and Critical Care Medicine in 2020 found that the nose can filter larger air particles but the mouth is not as effective. Smaller particles, therefore, have a higher chance of entering the lower respiratory tract through the mouth.
Masking, as has been the case for the pandemic years, will remain the first layer of protection.
The Brihanmumbai Municipal Corporation on April 10 made it compulsory for visitors and staffers to wear masks in government hospitals to control the spread of the infection.
“According to the Union health ministry, there is a possibility of an increase in the number of Covid patients in the month of May,” said commissioner Iqbal Singh Chahal.
