Covid virus is still here. Why aren’t more people falling ill?

Subject: Science and tech

Sec: Health

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In the first three weeks of that month, more than 3 lakh positive cases were detected every day on average.
Daily detections peaked exactly three years ago on May 6, 2021 when more than 4.14 lakh positive cases were reported.

Is the pandemic finally over?

On May 5, 2023, the World Health Organisation (WHO) announced that Covid-19 was no longer a global public health emergency.
India had withdrawn all Covid-19-related restrictions after March 31, 2022, shortly after the Omicron wave had dissipated and ceased the application of the provisions of the Disaster Management Act.

Why aren’t more people getting infected?

The Omicron variant, which emerged at the end of 2021, had enhanced capability to spread and infect people, but it did not cause severe disease.
A large proportion of the world’s population gained natural immunity after being infected with Omicron.
The decline in the number of people without immunity, either through natural infection or vaccination, meant that the virus had fewer opportunities to evolve rapidly into newer variants.
However, neither natural infection nor vaccines provide permanent immunity.
The effect of vaccines taken in 2021 and 2022 is most likely over.
Natural immunity also dissipates after some time.
The only reason there is no uncontrolled surge is that people are continuing to get infected with relatively harmless variants, and getting their immunity renewed.

About Covid 19 and its strains:

Coronaviruses are a specific family of viruses, with some of them causing less-severe damage, such as the common cold and others causing respiratory and intestinal diseases.
These are enveloped RNA viruses that cause respiratory illnesses of varying severity from the common cold to fatal pneumonia.
The dominant variant causing the most infections right now is JN.1, a distant descendant of Omicron. JN.1 is a little more efficient at infecting people than its sister variants but like all descendants of Omicron, does not cause severe disease.
The presence of Beta variant was first reported from India during December 2020.
Various SARS- CoV-2 variants i.e., Alpha, B. 1.1. 28.2, Eta, Kappa, Delta, Delta AY have been detected from India.
The Delta variant first detected in India remains the most worrisome.
- It has proven capable of infecting a higher proportion of vaccinated people than its predecessors.
- The WHO classifies Delta as a variant of concern, meaning it has been shown capable of increasing transmissibility, causing more severe disease or reducing the benefit of vaccines and treatments.
The Lambda variant has attracted attention as a potential new threat.

Types of Immunities:

Active Immunity results when exposure to a disease organism triggers the immune system to produce antibodies to that disease.
- Natural immunity happens after you get infected by a germ and your immune system responds by making antibodies to it.
Passive immunity is provided when a person is given antibodies to a disease rather than producing them through his or her own immune system.
- A newborn baby acquired passive immunity from its mother through the placenta.