According to The New York Times as of 27th April 2021, 1.06 billion have been vaccinated across the globe. All this is done to achieve the aim of herd immunity.
What is Herd immunity?
Herd immunity, or community immunity, is when a large part of the population of an area is immune to a specific disease. For example, if 90% of the population is immune to a particular disease, 9 out of 10 people will not get sick on meeting an infected patient. There isn’t a particular threshold that should be achieved in this case because the spread of a novel virus changes in the way people interact with each other and can be controlled at times, just like implementing lockdowns for Coronavirus. This protects the at-risk population like infants.
How is Herd Immunity Achieved?
- Natural infection: Herd immunity can be achieved naturally if a huge number of the population recovers from the disease. In this case, the recovered people become immune to the disease. For herd immunity to be achieved for COVID-19, about 70% of the population must be immune. This will lead to the death of millions of people, especially in the older age group. Also, we can’t be sure for how long this immunity will be carried forward. In the case of COVID-19, a study in a controlled environment in Denmark shows, reinfections can occur after 6 months of the first infection.
- Vaccination: This is the safest way to achieve herd immunity as vaccines do not cause illness to the person to which it is administered. It is an age-old method and has helped to eradicate various widespread diseases like polio, smallpox, measles, rubella and many more.
Can achieving herd immunity create an impact?
There are some reasons which make the picture of achieving herd immunity hazy. It is still ambiguous if vaccines prevent transmission. A vaccinated individual may transmit the virus to others. Also, there is an uneven distribution of vaccines. Some countries are around the threshold but pulverising the virus is still a big challenge. The endurance of the acquired immunity is still to be speculated. With the entire human race at risk of infection, statisticians will have to do a great job for data collection for the case of this pandemic. Variations will be huge and hence concluding to data will be difficult. Moreover, the virus is mutating more rapidly than contemplated. Vaccines are proving useful against some but not against all.
So, can herd immunity really be achieved? Well, the answer is not just a simple yes or no. The transmission of the virus is changing due to social behaviours. If we follow all protocols like wearing a mask in the instructed manner, maintaining social distancing, sanitising regularly and vaccinating ourselves when our chance comes, brings us closer to herd immunity and back to normal. However, if these protocols are not followed diligently, herd immunity will be a faraway dream.
The article has been written by Ritu Katkar for The Paradigm
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