Stepping up Adult Immunization: A Clarion Call for Equitable Health

Why do We Need Vaccination in Adults?

Vaccine-preventable diseases (VPDs) affect thousands of adults resulting in high morbidity, mortality, and consequent economic burden. Many childhood vaccine-preventable infections are now found among adults too as the vaccine-induced immunity may not have the same long-term stability as disease-induced immunity, raising the average age of incidence for various vaccine-preventable diseases, for example, pertussis and measles.

The vaccinated individual is not only protected from developing a potentially serious disease but also there is a reduction in the spread of diseases into the community.

Vaccine coverage ultimately leads to herd immunity that will protect the community at large indirectly.

Vaccine-preventable diseases cause major disruptions on college campuses, in the workplace, and in institutions such as hospitals and are responsible for large economic losses eventually.

Adult vaccination thus helps to reduce hospitalization costs for preventable diseases, disease outbreaks (e.g., flu, pneumonia) and burden on healthcare systems.

Barriers to Adult Immunization

Adult immunization coverage in our country is low, to say the least.

Studies in India have documented vaccination uptake ranging from 0.6% for pneumococcal vaccine to 1.9% for typhoid and hepatitis B vaccines. The estimated percentages of respondents reporting ever being vaccinated were 1.5% for influenza.

The underlying factors are multifarious. One of the most important in resource-limited countries is the cost.

Adult vaccines are not free like pediatric vaccines and people pay from their own pockets.

• Till now public health agencies have been negligibly involved with adult immunization.

• The cost of vaccination—including purchase, distribution, storage, and administration costs—can affect uptake.

• Moreover, the indigenous production capacity of vaccines used for adult immunization is limited and import charges add to the cost.

But Finances are Not the Only Issue in Vaccine Hesitancy or Poor Vaccine Coverage

• The healthcare providers and beneficiaries are not fully convinced that adult vaccine-preventable diseases are significant health problems.

• There are doubts about the efficacy and safety of several of the vaccines used for adults.

• Adult immunization is selective, not universal, different vaccines have different target groups. Hence reach of vaccines is compromised.

What is the Way Forward?

• Improving provider and public awareness.

• To ensure that the healthcare system has an adequate capacity to produce vaccines indigenously.

• To devise comprehensive strategies to deliver vaccines to adults.

• Employer-sponsored vaccination may be advocated or employer incentives to provide workplace vaccinations.

• Other options are mandatory insurance coverage for essential vaccines or public–private partnerships to lower costs.

• The best solution would be a national program for free vaccination of adults, if not possible, at least government subsidies for all adult vaccines.

• Another vital much-needed policy for the government is the prioritization of R and D to produce affordable, safe, and effective vaccines that are needed for the Indian markets.

• Prior identification of vaccines most suitable for the public health standpoint may be helpful. For that adequate surveillance studies are of utmost importance.

To Conclude

As we look upon the age-old adage “Prevention Is Better Than Cure,” we all realize that robust vaccination is the most beneficial and cost-effective way to prevent and control infectious diseases in adults. World Health Organization (WHO) and Centers for Disease Control (CDC) recommend a life course approach to immunization.

The consensus document released in 2024 by the Association of Physicians of India in collaboration with 13 other national societies aptly summarizes the guidelines for vaccination in adults and it is the responsibility of us health professionals to take up the challenge, leading by example and blaze the path to equitable health for the community at large.

The cost of vaccination—including purchase, distribution, storage, and administration costs—can affect uptake. While childhood vaccinations included in India’s Universal Immunization Program are free of cost, the cost of adult vaccinations (apart from TT/Td during pregnancy) is currently borne by the individual.

SUGGESTED READING

1. Menon GR, Singh L, Sharma P, et al. National Burden Estimates of Healthy Life Lost in India, 2017: An analysis using direct mortality data and indirect disability data. Lancet Glob Health 2019; 7(12):e1675–1684. DOI: 10.1016/S2214-109X(19)30451-6.

2. Martínez-Baz I, Aguilar I, Morán J, et al. Factors associated with continued adherence to influenza vaccination in the elderly. Prev Med 2012;55(3):246–250. DOI: 10.1016/j.ypmed.2012.06.020.

3. Rizvi AA, Singh A. Vaccination coverage among older adults: A population-based study in India. Bull World Health Organ 2022;100(6):375–384. DOI: 10.2471/BLT.21.287390.

4. International Institute for Population Sciences (IIPS) and NPHCE, MoHFW. Longitudinal Ageing Study in India (LASI) Wave 1, 2017–2018, India Factsheet, International Institute for Population Sciences, Mumbai.