By Dr Bilal Shirazi | 14 Apr 2021

How do vaccines impact public health and society?

The COVID-19 pandemic has brought vaccines to the front and centre of the public consciousness. Ahead of World Immunization Week, we explore how vaccines impact public health and society as a whole.


While the world remains gripped by COVID-19, it’s almost impossible to read or see a news bulletin about the pandemic that fails to reference the ongoing rollout of vaccines across the world.

Although the pandemic has brought vaccinations to the forefront of global thinking, the truth is that vaccination programmes remain a fundamental part of reducing the global healthcare burden. Indeed, such is the importance of vaccines that the World Health Organization (WHO) cites access to clean water as the only thing more effective at reducing the prevalence of infectious diseases.

Despite vaccines' profound impact on how we deal with infectious diseases, we hear more about vaccine safety concerns than we do about their effectiveness. This is currently being widely seen with the Oxford-AstraZeneca COVID-19 vaccine.

With the upcoming World Immunization Week on the horizon, let’s look at the role vaccines play in affecting public health and their role in society as a whole.

Vaccines and disease control

Vaccines are often thought of in the context of helping to eliminate diseases. However, we must always consider that, to date, only smallpox has been 100% eradicated, although eradicating other diseases remains possible.

It's more helpful to think about vaccination in the context of controlling diseases.

For example, we know that most vaccines aren't 100% effective. However, they are effective to a high enough extent that, according to the WHO, they save six million lives a year.

In certain regions, vaccinations have proven effective at massively reducing the instances of specific infectious diseases. For example, the United States Centers for Disease Control and Prevention cites 14 diseases that have “almost been forgotten” thanks to vaccines. Likewise, seasonal flu claims the lives of hundreds of thousands of people per year. However, many more would die – and hospitals would be under overwhelming pressure from flu admissions – were it not for vaccines.

Vaccines and mitigating the severity of disease

One of the least understood factors of vaccines is that they typically have different objectives and perform different roles.

For example, some vaccines cannot prevent you from becoming infected. Still, they can prevent the development or severity of a disease if you do. This is something else we see as we learn more about how COVID-19 vaccines work. While there is currently little evidence that vaccines prevent infection or act as a barrier to transmission, they have a clear impact on the severity of disease among those who do become infected.

Vaccines help those who aren’t vaccinated, too

The concept of herd immunity is one that many of us have learned about in the past 12 months. While it has proven controversial in the context of COVID-19, it remains a vital pillar of any vaccine programme.

For example, according to the WHO, Hib disease in The Gambia was eliminated despite vaccine coverage being under 70%.

While some people are hesitant about receiving vaccines, many clinically vulnerable people cannot receive a vaccine due to their condition. As such, high uptake of vaccines in the community can help protect these people by preventing disease and reducing their chances of acquiring an infection.

The role of vaccines in preventing related diseases

As well as preventing the "headline" infection or disease, vaccinations also protect us by preventing the development of associated conditions.

For example:

  • Vaccination against hepatitis B can help prevent the development of liver cancer and protect you from hepatitis D.
  • In children, the flu vaccine can prevent the common ear infection otitis media.
  • Measles vaccines can prevent conditions like bacterial pneumonia and dysentery.
  • The COVID-19 vaccine can prevent associated conditions like pneumonia. However, it remains to be seen whether it reduces the prevalence and effects of long COVID.

The broader role of vaccines in general society

Overall, vaccines play a vital role in the development of our entire global society, with an impact that is profound and far-reaching.

Among other things, vaccines help to:

  • Reduce healthcare burdens and costs.
  • Prevent the development of antibiotic resistance by reducing the need for their use.
  • Extend life expectancy.
  • Make it safe to travel to different parts of the world.
  • Empower women socially and economically.
  • Promote economic growth.
  • Enhance and promote equality and equity.
  • Promote peace and reduce the risk of bioterrorism.

It's easy to get caught up in thinking that receiving a vaccine is doing little more than protecting yourself from a specific disease. However, as you can see, its effects are far-reaching and potentially world-changing, particularly if more of us take advantage of vaccines when they are available.

When is World Immunization Week and what are its aims?

World Immunization Week is always the last week in April. As such, World Immunization Week 2021 will be marked from 24th – 30th April.

As with most health awareness events, World Immunization Week is organised and predominantly promoted by the WHO on a global and regional level.

Given the role that vaccines are playing – and will continue to play in the coming months and years – in reducing the spread of COVID-19, this year’s theme of “Vaccines bring us closer” is a poignant one. Using this theme, the WHO is looking to create more partnerships with stakeholders around the world to achieve the following objectives, which are again highly relevant against the background of the pandemic:

  • Increasing trust and confidence in vaccines to maintain and increase the uptake of vaccines where and when they are available.
  • Increasing overall investment in vaccine development to cement initiatives like routine immunisation and remove barriers to access for all.

Getting involved with World Immunization Week

If you’re interested in learning more about how you can get involved with World Immunization Week, the WHO’s campaign site for this year’s event features a wealth of resources and details on what you can do to promote the event at home, in your workplace, or around your community.

By Dr Bilal Shirazi

Dr. Bilal has more than 17 years of experience working across clinical medicine and the health insurance sector, with particular expertise in health insurance administration and operations. In addition to his Bachelor of Medicine and Bachelor of Surgery degree (MBBS), he has an MBA and is an Associate Member of the Life Office Management Association (LOMA).  

See Dr Bilal Shirazi's profile