You’re never too old to get immunised!

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Are vaccines only for children? It’s a myth, says Dr. Vasant Nagvekar, who believes strongly that adults have an equal need and responsibility to vaccinate themselves against various diseases. Consult your healthcare provider to determine your level of risk for infection and your need for a vaccine, he urges.

The two most effective means of preventing disease, disability, and death from infectious diseases have been sanitation and immunisation. The practice of immunisation dates back hundreds of years. Edward Jenner is considered the founder of vaccinology in the West in 1796, after he inoculated a 13-year-oldboy with vaccinia virus (cowpox), and demonstrated immunity to smallpox. In 1798, the first smallpox vaccine was developed.

Over the 18th and 19th centuries, systematic implementation of mass smallpox immunisation culminated in its global eradication in 1979. Despite the evidence of health gains from immunisation programmes, there has always been resistance to vaccines in some groups. The late 1970s and 1980s marked a period of increasing litigation and decreased profitability for vaccine manufacture, which led to a decline in the number of companies producing vaccines.

The past two decades have seen the application of molecular genetics and its increased insights into immunology, microbiology and genomics applied to vaccinology. Vaccination started with adults and presently, at least in India, there is hardly any concept of adult vaccination. GIVS (Global Immunisation vision & strategy 2006 – 2015) WHO UNICEF vision says every child, adolescent and adult must have equal access to immunisation as provided for in their national schedule.

Why do adults require vaccines?
Vaccine preventable diseases specifically influenza and pneumococcal diseases kill hundreds of times more adults than children every year. Adult immunisation coverage levels are low. Following are some vaccine-preventable diseases and their mortality and morbidity rates:

  • Typhoid affects 1 per 100 and multidrug resistant typhoid is rising.
  • There are 350 million chronic hepatitis B carriers worldwide.
  • Meningococcal infection has a mortality of 10–15 %.
  • Chicken pox in adults has 15–25 times higher mortality than children.
  • Severity of Hepatitis A is age related and fulminant hepatic failure results in death.
  • All the above vaccines are preventable in adults. Senior citizens are more susceptible to serious infections caused by common pathogens. Some of the vaccines received in childhood, their immunity declines over a period of time especially Tetanus and Pertusis, and require a booster dose to protect in adulthood. Also getting vaccinated against pertussis is known to be protective for small babies at home.

    One of the most important reasons adults identify for not receiving a vaccine is the lack of provider recommendation for the vaccine. Apart from ignorance about adult vaccines, there is a general feeling that immunisation is only for kids. There is needle phobia, cost, vaccine myths, and limited access to vaccines, all of which contribute to lack of awareness for adult vaccination.

    The main adult vaccines available are:

  • Tetanus and diphtheria, which have a 10 year protection of >99%.
  • Flu (Influenza) taken yearly has a protective rate of 50-70% and varies with the strain. Last year’s flu vaccine possibly had a lesser coverage due to a mutant strain circulating in the community.
  • Invasive Pneumococcal disease 3-5 years protection is 60-70%.
  • Hepatitis B has a >15years protection of more than 90%.
  • In Hepatitis A, studies have shown a 20 year protection of 99%. Protective antibody levels develop in 95% of adults one month after the first dose is given in a two-dose series. Nearly 100% of all persons studied had protective levels of antibody after the second dose, given 6-12 months after the first.
  • Live Vaccines like MMR (Measles, Mumps, Rubella) and chickenpox have lifelong immunity of more than 99%. It’s disastrous to get exposed to or suffer from Rubella and chickenpox during pregnancy, if not having protective antibodies.
  • The Meningococcal vaccine which prevents against meningococcal meningitis has a protection rate of more than 85% and is recommended especially for travellers going on pilgrimage, and for students staying in dormitories.
  • HPV (Human Papilloma Virus) has almost 100% protection against the strains in the vaccine and recommended to females preferably before menarche and up to 26 years of age, to prevent carcinoma of cervix, and for homosexuals to prevent anal warts and rectal and anal malignancy.
  • The new vaccine against Herpes zoster gives around 50-60 % protection and is recommended for adults aged more than 65 years.
  • Recommended adult vaccines
    Routine Influenza vaccination is advisable for all elderly people above 50 years and health care providers. Certain populations have higher incidence of Invasive Pneumococcal Disease (IPD) and are vaccine preventable. For example, adults who have chronic heart disease are three times more at risk for IPD.

    Similarly, adults or children having structural heart disease or diabetes or adults having Chronic Obstructive Pulmonary Disease are six times more prone for IPD. Alcoholics are eleven times and immunocompromised patients are 25 to 50 times more prone to develop IPD. Not only underlying comorbid conditions are more prone but as age increases, with underlying comorbid conditions, the risk of developing IPD also proportionally increases.

    Diabetics are about three times more likely to die with flu and pneumonia. Diabetics have a normal humoral response to pneumococcal vaccination. Pneumoccocal immunisation in diabetic patients significantly reduces morbidity and mortality related to pneumoccocal disease.

    Yearly influenza vaccine taken especially among elderly and those having comorbid conditions, reduces hopitalisation risk by upto 40 % and reduces the morbidity and mortality. The new pneumococcal conjugate 13 valent vaccine not only has an impact on IPD but reduces the risk of developing pneumonia by 45%.

    Influenza vaccines are effective in the prevention of influenza illness, although improved vaccines are needed. Inactivated and live-attenuated vaccines are available in trivalent and quadrivalent formulations.

    The objectives of vaccination include protection of the individual, as well as protection of the population through herd immunity. Flu vaccination of adults is also associated with decreased absenteeism from work or school and is significantly cost effective, but these benefits may not be seen in years when there is not a good match between vaccine and circulating viruses

    Conclusion
    Vaccines aren’t just for kids. Getting vaccinated not only protects you from diseases, it can also help you protect the health of people around you, who may not be able to get vaccinated themselves, like infants and people going through cancer treatment. Vaccines are for everyone, not just children.

    In fact, there are some vaccines that are specifically recommended for adults. These ‘adult’ vaccines protect against diseases that are more common in adults than children. Some vaccines protect against diseases that can be more serious when contracted by adults. Other adult vaccines may actually be boosters of vaccines that you received as a child. Boosters “refresh” the immune system’s memory of how to make the tools to fight a pathogen, so that it can continue to provide protection against the disease. We can conclude that adult immunisation must become a fundamental part of routine patient care. Adult vaccination saves lives.


    Dr.-Vasant-Nagvekar

    Dr. Nagvekar

    Dr. Nagvekar is attached to Lilavati Hospital, Bandra, and Global Hospitals as Infectious Diseases Consultant.

    Dr. Nagvekar is attached to Lilavati Hospital, Bandra, and Global Hospitals as Infectious Diseases Consultant.

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