Covid-19 dynamics- Important data and solutions

Covid-19 dynamics- Important data and solutions

Introduction

• This article talks about the rapid rise of the covid-19 in the second wave, its major reasons, data and the steps to be taken.

Infection dynamics

• Earlier, we concluded that at the end of the first wave, 60% of the population had been infected (828 million).
• The uninfected 40% would be 1,380 million minus 828 million = 552 million.
• According to a recent Indian Council of Medical Research report, the reinfection rate in India is 4.5% — out of 828 million initially infected, 37.26 million are susceptible to reinfection.
• The total number of susceptible subjects for the second wave would be 552 million+37.26 million = 589.26 million.
• We calculate the rate of increase of new cases by looking at the daily new cases of the first and second waves at time points when the daily numbers were nearly equal.

Herd immunity level needed for 2^nd wave:

• The herd immunity level required to bring the numbers down to end the second wave (herd immunity threshold) would be about 75%-80%, in contrast to 60% for the first wave — in terms of actual numbers, a maximum of ~471 million (80% of 589.26 million).

Diagnosis level of 2^nd wave:

• Of the 828 million infected in the first wave, only 10,904,738 (1.32%) were diagnosed by February 13, 2021.
• By the same token, only 6.223 million (1.32% of 471.4 million) are likely to be diagnosed by the end of the second wave.
• At the peak, the numbers detected would be half, namely 3.1 million.

Vaccination drive

• Our current pace of vaccination (only 1% of the population has completed two doses so far) and the two week interval required after the second dose of the vaccine to confer sufficient immunity to decelerate the second wave, indicate that vaccination may not decelerate the second wave in India.
• However, we hope that the elderly and vulnerable, who were prioritised for vaccination, will have reduced mortality.

Deepened by lapses

• The faster-spreading U.K. variant was involved in the second wave in Punjab; judging by the tempo of spread, either this variant, other known variants and possibly faster-spreading Indian variants are responsible for the second wave in the country.
• Vaccine hesitancy, policy hesitancy and fast-spreading virus mutants all added to the tempo of the second wave.
  • We let our guard down too early — a costly error.
• A larger number of symptomatic infections in youngsters in the second wave may be attributable to their higher mobility and premature opening up of schools and colleges in the face of highly infectious variants.

The strategy ahead

• We should insist on the golden rules of mask wearing, cough etiquette, maintaining physical distance, hand-hygiene and avoiding crowds, and pursue an aggressive vaccination drive to contain the situation without imposing a lockdown, which will hurt the recovering economy and lead to untold public misery.
• Travel curbs for fully vaccinated individuals are being lifted in the United States.
• In India, vaccination can be made a pre-requisite for those who come in contact with large numbers of vulnerable people (for example, teachers).
• Vaccination at offices (started in Tamil Nadu) and persuading staff in the Indian Railways to get vaccinated quickly are innovative steps in the right direction.
• If vaccination is a pre-requisite for any public assembly, fewer people will gather and more people will seek vaccination.
• If vaccination is a pre-condition for entry into crowded public places and use of public transport, those who use these facilities will feel safe and the public will accept vaccination readily.
• Mobile vaccination vans can cover inaccessible rural pockets and reach people unable to reach vaccination centres.
• If all public figures wear masks in all their public appearances, citizens will get a clear and effective message.
• The government’s decision to give emergency use authorisation to all World Health Organization-approved COVID-19 vaccines is likely to narrow the demand-supply gap.
• The mRNA vaccines, which appear to offer greater protection against new variants and other vaccines in the pipeline to cover variants of concern need to be mass produced, tested and commissioned quickly to benefit everyone.