[Editorial] Taming the 3rd Wave

Background:

The Omicron variant of the SARS CoV 2 was first detected in Karnataka. Within a month, this new variant has started driving the upsurge of COVID-19 cases in India.
The massive 2^nd wave was driven by the Delta variant, which eventually became endemic. Between July and December, India experienced a lull in the number of cases. For the most part of 2021-end, the caseload remained below the 10,000 mark.
However, on December 29^th, India recorded over 13,000 cases. By January 6^th, the daily number of cases crossed 90,000.
India has been testing at a steady rate, but the test-positivity rate (percentage of tests that give a positive for COVID-19) has risen. This confirms the onset of the 3^rd wave of the pandemic.
Some states are currently an exception to this trend- Kerala, Sikkim and Arunachal Pradesh. These states experienced the onslaught of the Delta variant later than the rest of the states. They also witnessed later peaking of cases.

How dangerous is the Omicron variant?

In November, WHO labelled the Omicron as a variant of concern (VoC). This declaration came within 2 days of South African scientists notifying it. The WHO gave the countries a heads-up about the oncoming onslaught of infections.
The variant was declared a VOC for 2 reasons:

1. Extremely high transmission efficiency– even more than the Delta variant’s capability
2. Ability to evade immune response of the host

These 2 properties are the products of numerous mutations on the virus’ spike protein gene. While the Delta variant has 2 mutations on its spike protein’s receptor binding domain, the Omicron variant has 15.
As a result of these mutations, the antibodies of the host aren’t able to bind the virus’ spike protein. This has made the antibodies, induced by all the current vaccines, relatively ineffective against this new variant.
However, the new variant causes disease in a much smaller percentage of the people it infects and causes a much milder version of COVID compared to the disease caused by the Delta variant.
Compared to the disease witnessed in the previous 2 waves, the current variant triggers fever, pneumonia and hypoxia is far lesser frequency.

Why should it be taken seriously?

The new variant poses risk of severe disease to the vulnerable population i.e. the elderly and the immune-compromised. Such cases could call for hospitalization and have a high risk of mortality.
The variant could trigger a rapid spread of infection of unpredictable proportion- probably less than the 2^nd wave but more than or equal to the 1st wave.
Many have been trivializing the new variant as “the vaccine that scientists could not design”, in reference to the mild disease it causes. This is a dangerous notion as the number of people needing intensive hospital care for severe form of disease is much higher compared to the number of hospitalizations for serious adverse reactions following vaccination.
Though the risk of severe disease from this new variant is low for the young and healthy sections of the population, it is not zero. Hence, inaction would not only be unscientific, but also unethical.

What could be done?

When the 1^st wave hit, we didn’t have a vaccine to flatten the curve. By the time the 2^nd wave hit, we had been in possession of vaccines for 3 months, but we failed to flatten the curve due to insufficient stocks and ineffective distribution plan.
As a result, many lost their loved ones and the economy took a hit. The low- and middle-income families have been especially affected and continue to face severe financial stress.
In case of the 3^rd wave, we had a unique opportunity to minimize the disease burden and mitigate the wave of infections. We were presented with an opportunity to develop boosted immunity– both vaccine induced and hybrid (arising from previous infection and vaccination), by initiating a booster vaccination campaign.
UK’s experience shows strong evidence for booster dose’s effectiveness. Booster doses trigger an increase in antibody levels to offer protection from severe disease. This can be seen from how the real time protection against hospitalization-requiring disease caused by Omicron was 72% in the 2 to 24 week period after 2^nd dose, but only 52% after 25 weeks. The protection offered shot up to 88% in the 2 weeks after the booster dose was administered.
Unfortunately, the policymakers waited a month before taking actions that were far too insufficient to address hospitalization needs and slow the spread of the virus.
Another important aspect of fighting the Omicron variant is immunization of children. The new vaccination policy covers only a small percentage of the under-18 population. Unfortunately, it is now too late to pursue this strategy as the 3^rd wave is expected to peak within weeks whereas developing immunity takes 6 weeks from the date of administration of the 1st dose.
What can be done is strict adherence to COVID-appropriate behaviour i.e. double masking, ensuring hand hygiene, maintaining proper indoor ventilation and avoiding crowds and non-essential travel.