Journal of Clinical Immunology Research

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Short Communication - Journal of Clinical Immunology Research (2022) Volume 5, Issue 1

COVID-19 pandemic and herd immunity: Whats known and what to know.

Jean Laurent Casanova*

Howard Hughes Medical Institute, Rockefeller University, New York, USA

*Corresponding Author:
Jean Laurent Casanova
Howard Hughes Medical Institute
Rockefeller University
New York, USA
E-mail: [email protected]

Received: 08-Feb-2022, Manuscript No. aacir-22-56499; Editor assigned: 09-Feb-2022, PreQC No. aacir-22-56499 (PQ); Reviewed: 18-Feb-2022, QC No. aacir-22-56499; Revised: 23-Feb-2022, Manuscript No. aacir-22-56499 (R); Published: 28-Feb-2022, DOI:10.35841/56499-5.1.104

Citation: Casanova JL. COVID-19 pandemic and herd immunity: What’s known and what to know. J Clin Immunol. 2022;5(1): 104

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Are you interested in learning more about the progress being made toward herd immunity against the coronavirus illness 2019 (COVID-19)? Learn about herd immunity, its role in eradicating the COVID-19 epidemic, and the issues it poses. Significance of herd immunity: When a considerable section of a society (the herd) gets immune to a disease, disease transmission from person to person becomes rare. As a result, everyone in the community is protected, not just the immune [1].

In order for a disease to spread, a certain percentage of the population must be susceptible to it. A threshold proportion is what it's termed. If the proportion of the population immune to the disease exceeds this threshold, the disease's spread will be slowed. The herd immunity threshold is the term for this [2].

To obtain herd immunity, what percentage of a population must be immune? It differs from one sickness to the next. The bigger the fraction of the population that must be immune to stop a disease from spreading, the more infectious it is. Measles, for example, is a highly contagious disease. To break the chain of transmission, 94 percent of the population would have to be immune [3].

How does herd immunity work?

Infection and vaccinations are the two main routes to herd immunity for COVID-19. Infection that occurs naturally, herd immunity can be reached when enough persons in the population have recovered from an illness and have generated protective antibodies against future infection.

However, there are some serious issues with depending on community infection to build herd immunity to the virus that causes COVID-19:

Reinfection-After recovering from COVID-19, its unclear how long you'll be protected from getting sick again. COVID-19 can resurface even if you have antibodies.

The effect on one's health: The high number of infections could result in major complications and millions of deaths, particularly among the elderly and those with pre-existing medical issues. The health-care system might become overburdened very fast.


Herd immunity is obtained when a large number of people have been vaccinated against a disease and have produced protective antibodies against future infection. Vaccines, unlike natural infections, provide immunity without causing disease or other complications. By utilising the idea of herd immunity, vaccines have successfully eliminated communicable illnesses such as smallpox, polio, diphtheria, rubella, and many others [4].

Herd immunity allows the population to be protected from a disease, even if some people cannot be vaccinated, such as infants or individuals with impaired immune systems. Vaccine reluctance; Some people may be hesitant to get the COVID-19 vaccine because of religious views, fears about potential side effects, or a lack of knowledge about the benefits. If the number of vaccinated persons in a community falls below the herd immunity threshold, a dangerous disease could continue to spread.

Concerns about safety; its unclear how long COVID-19 immunizations will keep you safe from the virus. More research is needed to assess how effective the COVID-19 vaccines are at reducing COVID-19 viral transmission. Furthermore, research suggests that COVID-19 vaccinations may have lesser efficacy against specific COVID-19 virus types. New variations that may be more resistant to vaccines appear on a regular basis [5]. Inconsistent vaccination distribution; COVID-19 vaccination distribution has varied widely between and within countries. If the populations mingle and one town achieves a high COVID-19 immunisation rate while the adjacent communities do not, outbreaks can arise.

How may COVID-19 transmission be slowed?

Obtain a COVID-19 vaccine if at all possible. If you're fully vaccinated, you'll be able to resume activities that you may have been unable to accomplish due to the pandemic. If you live in an area where there are a lot of new COVID-19 cases, you should continue to wear a mask indoors in public and outside in populated locations or when you are in close contact with persons who aren't completely vaccinated. Maintain a consistent pattern of appropriate behaviour [6].


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