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Letter to Editor

Herd immunity

Deadly or defensive

Khan, Sameena; Mirza, Shahzad; Das, Nikunja K.; Patil, Rajashri

Author Information
Journal of Family Medicine and Primary Care: September 2021 - Volume 10 - Issue 9 - p 3522-3523
doi: 10.4103/jfmpc.jfmpc_482_21
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Herd immunity, the most popular idea that is floating around in the minds of the general public, has now become a household name. It is a type of indirect protection wherein communities become immune to a contagious disease and as a consequence, it is supportive to those who are vulnerable like those having an underactive immune system. It protects and reduces the need to vaccinate each and every person thus protecting even the nonvaccinated ones. No doubt herd immunity is genuine, and it can be achieved in two ways, either naturally by infection or artificially by vaccinations.[12]

SARS-CoV-2 is an infectious virus. Herd immunity will need a large majority of the population to be infected so that they become immune to the disease and stop the string of spread. But its natural arrival seems to be time-consuming and associated with some fatal consequences.[3] Indeed, herd immunity is so much to worry about if we let the infection sweep in every nook and corner around the globe. It would represent an unjust manner that would far outweigh the benefits. Contracting the disease can be grave and serious which is determined by the immune condition of the individual. The virus can spring up even if we are on top of herd immunity by natural routes. Children and the elderly will be more vulnerable due to a lack of immune defenses and waning of immunity. One can catch the disease easily and spread it too. This risk-based approach to build up immunity can be very dangerous.

It would be easy to conclude that our focus on herd immunity should be with the context of vaccine, rather than the natural way which will be at the cost of our population.[4] It is a risky and dangerous affair. Vaccine, the topmost priority of today, will bring an end to COVID-19 though with obstacles. The possibility is, now that the vaccine produced has a green signal with streamlined development and sufficient supply, it will flood the markets soon. What one expects is a safe and efficient vaccine which in itself a significant challenge. No doubt it is the most wanted wish of billions at present.[56]

Hence, people should be maintaining physical distancing measures and mask-wearing compliance even after the vaccine available. No single protocol can end the ongoing pandemic. The return to that life is still far away.

Let's be optimistic and follow long-term thinking rather than a short term approach. Hoping for a time in the future when we will have a vaccine against SARS-CoV 2, which will sow the seeds of herd immunity.

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Conflicts of interest

There are no conflicts of interest.

1. Muralidar S, Ambi SV, Sekaran S, Krishnan UM. The emergence of COVID-19 as a global pandemic: Understanding the epidemiology, immune response and potential therapeutic targets of SARS-CoV-2 Biochimie. 2020;179:85–100
2. Fine P, Eames K, Heymann DL. ''Herd immunity'': A rough guide Clin Infect Dis. 2011;52:911–6
3. Fine PE. Herd immunity: History, theory and practice Epidemiol Rev. 1993;15:265–302
4. Anderson RM, May RM. Vaccination and herd immunity to infectious diseases Nature. 1985;318:323–9
5. Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China Lancet. 2020;395:497–506
6. Jones D, Helmreich S. A history of herd immunity Lancet. 2020;396:810–11
© 2021 Journal of Family Medicine and Primary Care | Published by Wolters Kluwer – Medknow