Adult Vaccination in India: Addressing Practice Perspectives

In India, less than 2% of adults receive routine vaccinations for diseases like influenza, pneumococcal diseases, typhoid, and hepatitis B, which represent a significant public health burden. As a result, infectious and vaccine-preventable diseases (VPDs) continue to heavily affect adult health, contributing to high rates of morbidity, mortality, and health-economic burden.1

Dr. Indranil Halder, a veteran physician from Kolkata with a specialization in Pulmonary Medicine discusses the need and importance of adult vaccination in India, in an exclusive interview with Medical Dialogues.

The larger perception of Vaccines sync with their applicability in the pediatric population. Why do you think that adults too, require vaccines?

Pediatric vaccination is well-established and widely endorsed by the government of India. Public health authorities such as the World Health Organization (WHO), play a significant role in managing effective universal implementation. However, even in adults, increasing age leads to immunosenescence which becomes a significant concern, as it diminishes the immune function and heightens susceptibility to infections.

For instance, the clinical presentation of pneumonia differs significantly between a 25-year-old and a 65-year-old, with the latter suffering increased morbidity and mortality, as distinctly evidenced during the COVID-19 pandemic. Consequently, addressing these issues through targeted vaccination strategies in adults is imperative to prevent VPDs and mitigate age-related health risks.

Is the incidence of Vaccine-Preventable Diseases (VPDs) shifting to younger age groups in India?

Vaccinations were initially recommended for patients aged 65 years and above, which left patients above 50 years of age vulnerable to the sequels of complications associated with infections. However, we are now observing that respiratory diseases like influenza and pneumococcal pneumonia, are not only affecting the elderly; they are also seen in individuals in their 40s and 50s. As per the Longitudinal Ageing Study in India (LASI) study, non-communicable diseases (NCDs) often start a decade earlier, particularly between ages 45-55 than the developed countries. In fact, 26% of older adults aged 45 years and above have a single morbidity condition, while 18% have multimorbidity. This growing evidence in India suggests vaccinating the vulnerable younger age group as well.2

Why is it important to vaccinate at the age of 50 years for pneumococcal disease?

In developed nations like United States, under their national immunization program PCV13 is being administered to all children since 2010. This robust program has thus led to the development of herd immunity in adults for the 13 serotypes that are covered in PCV13. In India, PCV has been very recently added in the national immunization program, leading to incomplete population coverage and insufficient herd immunity for adults. With the pneumococcal incidence rate of 22.7% in adults between 44-60 years, it is crucial to enhance awareness and adherence to vaccination guidelines, which recommend pneumococcal vaccination, PCV13 followed by PPSV23 (1 year later) in individuals aged 50 years and above.3

Are the younger adults too at risk for pneumococcal disease?

Yes, pneumococcal vaccination is essential in India due to contemporary gaps in pediatric vaccination coverage and lack of herd immunity. Lifestyle habits such as Smoking, alcohol consumption, obesity have led to an increase in underlying medical conditions resulting in compromised immunity in younger adults. This shortfall contributes to the persistence of infections such as Chronic Obstructive Pulmonary Disease (COPD), tuberculosis, viral infections, and severe COVID-19 infections. This makes it clinically and medically justified to extend the benefit of pneumococcal vaccination to adults aged 18-50 years to prevent both non-invasive and invasive pneumococcal diseases.

What are the recommendations for pneumococcal vaccination in adults above 18 years?

Indian Consensus Guidelines on Adult Immunization is a collective initiative of Association of Physicians of India (API) along with 13 diverse medical societies including ICS (Indian Chest Society), to address a crucial aspect of Adult Immunization by bridging the existing gaps in adult vaccine understanding and implementation. The guidelines support the use of pneumococcal vaccines in adults aged 18-49 with underlying medical conditions (such as diabetes, Chronic lung, liver, kidney disease) and all adults aged 50 years and above. Pneumococcal conjugate vaccine, PCV 13 should be administered first followed by PPSV23, 1 year later (at risk conditions) or 8 weeks later (high risk conditions). (4)

Any final remarks for all healthcare stakeholders you may like to put forward?

Better awareness of the effectiveness and benefits of vaccination emphasized by clinicians to their patients is very critical. All patients having chronic diseases including respiratory, cardiac, diabetic, or malignancy should be advised for vaccination. Government and private agencies such as insurance companies need to collaborate to educate and implement action plans to mitigate the vaccine inertia among eligible adults for VPDs. Vaccination is safe and usually well-tolerated when appropriately used as per clinical guideline recommendations.

References:

1. Rizvi, Ali Abbas, and Abhishek Singh. “Vaccination coverage among older adults: a population-based study in India.” Bulletin of the World Health Organization vol. 100,6 (2022): 375-384. doi:10.2471/BLT.21.287390

2. The Longitudinal Ageing Study in India (LASI) 2020. Retrieved on 16th August 2024 from https://www.iipsindia.ac.in/sites/default/files/LASI_India_Report_2020_compressed.pdf

3. Dhar, Raja et al. “Clinical practice guidelines 2019: Indian consensus-based recommendations on pneumococcal vaccination for adults.” Lung India : official organ of Indian Chest Society vol. 37,Supplement (2020): S19-S29. doi:10.4103/lungindia.lungindia_272_20

4. Association of Physicians of India. The New Indian Consensus Guideline on Adult Immunization. 2024 Retrieved on 16 August 2024 from https://apiindia.org/reader/immunization