It is difficult to say if there will be a third COVID-19 wave. But it is certain that large outbreaks - sudden increase in occurrences of the diseases at a particular time and place - are possible.
Rather than terming the present scenario 'a wave', it is more accurate to call it large outbreaks. While some places are reporting a decrease in the number of cases, the country at large has been seeing an upward COVID-19 trend.
Large outbreaks pose a threat since the mutant variants are more infectious, and a large section of the populations is yet to get vaccinated.
We viewed the pandemic as a short-term problem, failing to see it as a challenge that would last a longer period of time.
Several people thought the spread of COVID-19 would end in a few months. We also believed that Indians were more immune, and that the country had won the war against the pandemic. More than the mutant variants of SARS-CoV-2, our complacency has led to the present crisis.
Mutation is not new
Viruses undergoing genetic mutation are not new. Viruses undergo change in their genetic structure to survive, and such changes lead to new mutant variants. We can't hold any one of the mutant strains solely responsible for the current crisis in the country, though it could be one of the several reasons.
We have not conducted a massive genomic sequencing of the virus. Our surveillance mechanism in this regard is lagging behind others. We can only make generic statements like "the virus needs a long time to undergo drastic mutation."
Virus in a hurry
If we look closely, it can be seen that each region in the country has a dominant virus strain. If B.1.1.7 variant is predominant in North India, N-440K variant is prominent in the south. Other regions have different variants.
The spike proteins help SARS-COV-2 infect the human body. The spike protein has undergone drastic change in several of the new mutant variants. These changes make the virus more infectious.
The highly infectious virus has spread fast and wide in a short period of time. The mutant variants are affecting more people in no time. We cannot, however, predict how fast the virus would spread, because it is dependent on several factors.
Keeping distance from each other is the best defence against the virus. This is not maintained everywhere, helping the mutant variants to spread fast. The mutant variants, however, are not more dangerous.
Will different variants affect the same person?
It is unlikely that different variants will infect the same person at the same time. Each variant has a different pattern and speed in spreading. This pattern requires more clarity.
New-gen vaccines needed
Vaccine is the major weapon against COVID-19. However, it cannot be considered as a magic wand. Though vaccines reduce the chances of contracting the virus, it cannot guarantee total immunity.
Studies have revealed that vaccines are effective against the virus to a greater extent. The delay in vaccinating a huge section of the society in a country like India is a matter of concern.
Vaccines developed with the original variant in mind need to be effective against its mutants. Realising this drawback, there is a necessity to develop new-generation vaccines.
(The writer is a prominent Immunologist and Honorary Professor at the Indian Institute of Science Education and Research)