Patient Education - AN OLD MAN IS LIKE A CHILD : WHY WE MUST VACCINATE THE ELDERLY.

AN OLD MAN IS LIKE A CHILD : WHY WE MUST VACCINATE THE ELDERLY.

The increase in elderly population is a worldwide phenomenon. It is due to increased life expectancy and decreased mortality resulting from improvement in healthcare: the advent of antibiotics, vaccines, newer treatments, diagnostics and improved standards of living. The increase in elderly population is more in developing countries than industrialized nations. 

Older adults need immunization for several reasons:

1. They may not have received the vaccines in their childhood 

2. New vaccines for adults have become available

3. Immunity acquired in childhood can fade with age

4. Older adults or those who are chronically ill are more susceptible to vaccine-preventable diseases and complications

5. With age, the immune system becomes weaker - a phenomenon called immuno-senescence 

6. Both herd immunity and cocoon immunity are enhanced by vaccinations leading to lessening or even eradication of infectious diseases

Multiple Vaccinations are available for The ageing population : 

1. Pneumococcal vaccine

Pneumococcal vaccine is available in two forms:

• Polysaccharide vaccine consisting of polysaccharides from 23 serotypes. This vaccine is less immunogenic, does not affect carrier rates, promote herd immunity, or protect from respiratory tract infections as there is no mucosal immunity. In immunocompetent adults, PPSV23 is indicated in those over the age of 65. The vaccine is also indicated for those with CKD, chronic obstructive pulmonary disease (COPD), cirrhosis, diabetes, HIV, lupus, cancer and those on chemotherapy or radiotherapy, long-term steroid, asplenia, or splenectomy. A single dose PPSV23 is recommended in immunocompetent adults. 
• Conjugated Vaccine with 13 serotypes consists of capsular polysaccharides covalently bound to diphtheria toxoid, which is highly immunogenic but nontoxic. This combination results in mucosal immunity and lifelong immunity. PCV13 is approved in several countries worldwide, for use in adults aged >50 years for the prevention of pneumonia and/or invasive disease caused by Streptococcus pneumoniaserotypes included in the vaccine. 

2. Influenza vaccine

• The available vaccine in India is a killed virus vaccine to be given intramuscularly. Other vaccines include nasal spray vaccines (containing live attenuated virus). As the influenza virus constantly mutates, a new batch is prepared every year. The vaccine becomes effective against influenza virus 2 weeks after administration. Since the peak influenza season begins in October and lasts till May, October-November are the best times to receive vaccination
• A trivalent inactivated vaccine  is used which contains two Influenza A and one  Influenza B virus.
• A single dose of inactivated flu vaccine in dose of 0.5 ml is given intramuscularly into the deltoid muscle.
• Vaccination is indicated in high-risk subjects, e.g., those with COPD, CKD, cardiac or lung diseases, hepatic, metabolic diseases (diabetes), hematological diseases, pregnancy, nursing homes, health care personnel, household contacts of children <5 years or adults >50 years, diseases which impair respiratory functions, and immunosuppressed individuals.
• Side effects include allergic reactions, Guillain Barre syndrome. High-risk individuals should not receive nasal spray live flu vaccine. The vaccine provides adequate protection against HINI infection.

3. Meningococcal vaccine

The quadrivalent vaccines contain 50 μg of each of the antigens A, C, Y, and W135 whereas the bivalent vaccine has only A and C antigens.

Two types of quadrivalent vaccines are available:

The meningococcal polysaccharide vaccine (MPSV4) does not induce herd immunity, has no effect on nasopharyngeal carriage, and can be used only in those >2 years age. MPSV4 is preferred for adults aged 56 years or older who have not received MCV4 previously and who require a single dose only eg. Travelers . 

The meningococcal conjugate vaccine (MCV4) provides herd immunity, reduces nasopharyngeal carriage, provides long-lasting immunity after 28 days of vaccination, but cannot be used for people >55 years. MCV4 (conjugated) is preferred for adults who are aged 55 years or younger as well as for adults aged 56 years or older who (a) are vaccinated previously with MCV4 and are recommended for revaccination, or (b) for whom multiple doses are anticipated.

4. Tetanus, diphtheria, and pertussis vaccine

All elderly adults (older than or equal to 65  years)  should  have  completed  a  primary series  of  diphtheria  and  tetanus  toxoids  and thereafter should receive a booster dose every 10  years.  dT  should  be  used  to  provide protection against both diseases. Persons with unknown  or  uncertain  histories  of  receiving diphtheria  or  tetanus  toxoids  should  be considered unvaccinated and should receive a full three-dose primary series of dT .

5. Varicella Zoster vaccine

Two vaccines, both containing an attenuated live VZV are currently available in India. All adults who have never had chickenpox should receive 2 doses 0.5 ml in deltoid area subcutaneously 6 months apart .

6. Hepatitis A Vaccine

Vaccines against hepatitis A virus (HAV) include inactivated vaccines as single antigen (HAV antigen) vaccines or combined with HBV antigens. Hepatitis A vaccine is indicated for all transplant candidates with CLD or those patients of end-stage renal disease (ESRD) who have chronic hepatitis B or C because of increased risk of fulminant hepatic failure.

7. Typhoid vaccine

The available vaccines for typhoid fever include inactivated whole cell vaccine, live oral Ty21a vaccine, injectable Vi polysaccharide vaccine, and Vi-rEPA vaccine.

 Three doses of Ty21a capsules/sachets are administered on alternate days. This series should be repeated once in every 3 years as a booster dose. The capsule formulation should be taken orally with safe water.

The Vi vaccine is given as a single subcutaneous or intramuscular dose of 0.5 ml, with revaccination every 3 years.

Conclusion 

The aged people not only suffer from frequent episodes of illness but the disease severity is also higher due to the age-related decline in immunity. The diseases result in a lot of expenditure and consequently decreased quality of life among elderly. It is estimated that vaccines can prevent more than half of deaths due to pneumonia and influenza. 

If the immunization for elderly is included in the National Immunization Program, it will benefit the elderly population and decrease complications, chronic long term care and its associated cost.