ROLE OF VACCINATIONS IN CHRONIC LUNG DISEASES.

VACCINES: SHIELDING DISEASED LUNGS FROM HIDDEN DANGERS !

Chronic respiratory diseases like Asthma, COPD, ILD and Bronchectasis are increasing in incidence world wide. WHO estimated that COPD is now third leading cause of death and Asthma affects over 350 million people. These diseases are characterised by recurrent infective exacerbations due to bacteria and viruses. Though treated,they may lead to progression of the disease, decline in lung functions like lung vital capacity and worsening prognosis.

Exacerbations are usually triggered by respiratory infections which can be bacterial or viral. Viruses like Influenza, RSV, SARS-COV-2 and Bacteria like Streptococcus Pneumonia, H.Influenza etc. are the causes. These infections not only precipitate exacerbations but also increase the risk of hospitalisations, mechanical ventilation and death. Because of the pivotal role of infections leading to exacerbations, preventive stategies are necessary to maintain stable lung function. 'VACCINATION' is a corner stone of such preventive measures. They protect patients against common respiratory pathogens and reduce frequency and severity of exacerbations. For example, Seasonal Influenza vaccination reduces exacerbations in COPD patients by up to 40%. Pneumococcal vaccination significantly decreases risk of Community Acquired Pneumonia and Invasive pneumococcal disease and life threatning complications.

Now there is increasing recognition of the importance of prevention of non respiratory infections such as Herpes Zoster ( HZ) in individuals with chronic lung diseases. These patients are at higher risk of HZ due to impaired immune responses associated with these diseases, the use of cortico steroids and the overall burden of clinical HZ reactivation. It can not only lead to severe complications like Post Herpetic Neuralgia (PHN) but also indirectly exacerbates underlying respiratory condition through systemic inflammation and prolonged recovery periods.

PNEUMOCOCCAL VACCINATIONS available in India:

Two vaccines are available and approved for use in India.

1.PCV 13 (13 valent Pneumococcal Conjugate Vaccine)

2.PPSV 23 (23 valent Pneumococcal PolySaccharide Vaccine).

These vaccines prevent pneumonia, acute otitis media, sinusitis and also invasive complications like sepsis, meningitis, empyema and bacteremia.

INFLUENZA. VACCINES :

Immuno activated influenza and live atenuated vaccines are available and safe to use in immunocompromised conditions. Precautions are required in patients with egg allergy. Both trivalent and quadrivalent vaccines are available. The Global Influenza Surveillence Programme by WHO advises the virus strains with epidemic potential for use in Influenza vaccine. India belongs Southern hemisphere and is advised Influenza vaccinations in the month of September - October every year by WHO.

The flu vaccine provides protection against Influenza B (54 %), Influenza A (H1N1- 61% and H3N2 33%.)

Table to explain vaccination schedule for patients in India:

Vaccination	Patient Type	Vaccine Type	Dose
Pneumococcal vaccine	19 to 64 years -with Immuno competent conditions like Chronic liver, heart, lung diseases and poorly controlled DM and Immuno compromised conditions like HIV, CRD, Malignancies	1 dose PCV 13 and 1 dose of PPSV23 after eight weeks: Again 1 dose of PPSV 23 after 5 years.	PCV 13: 0.5cc IM / PPSSV 23: 0.5cc IM/SC
	All persons>65 Vaccine naive: Vaccinated in past	PCV 13 followed by PPSV23 after one year. PCV 13 one year after PPSV 23
Influenza vaccine	Elderly more than 50 Years, patients with chronic illnesses and pregnant women	Inactivated inflenza vaccine (IAIV) every year in September to October.	0.5cc IM

CDC (Centers for Disease Control and Prevention), recommends:

1. RSV vaccine (Respiratiory Syncytial Virus) vaccination in people more than 60 years with chronic lung diseases.

2. Tdap vaccine :Tetanus, Diphtheria and Pertussis ( whooping cough) vaccine in COPD patients who were not vaccinated in adoloscence.

3. Zoster vaccine (Shingles): in adults with COPD aged more than 50 years.

IN THE END, VACCINES ARE NOT JUST FOR CHILDREN OR FOR TIMES OF OUTBREAKS -- THEY ARE LIFELONG PROTECTORS,ESPECIALLY FOR THOSE LIVING WITH CHRONIC LUNG DISEASES.