Vaccination refers to the process of acquiring immunity against a specific disease, with the aim of avoiding and reducing infections. Everyone is aware of the vaccinations that are given to one in childhood, so much so that we’ve generally come to associate the word vaccination with children alone. But there are many diseases in adults which too could be prevented through vaccines, something that has become more or less routine in Western countries. The good news is that even in third world countries like Nepal, adult vaccination is slowly gaining more momentum as doctors and patients become more aware of its advantages. 

Vaccination has an important role in preventing both communicable (CD) and non-communicable (NCD) diseases in adults. Vaccine-preventable CDs include influenza, pneumococcal infections, meningitis in endemic areas, herpes zoster, human papillomavirus infection which leads to cervical cancer, and hepatitis B which can lead to cirrhosis and liver cancer. As for NCDs, many of these conditions have increased morbidity and mortality due to the patients suffering compromised immune systems. Diseases like diabetes, heart failure, kidney failure, chronic obstructive pulmonary disease, asthma, and cancer tend to weaken our immunity, making us prone to infections. Similarly, patients with HIV or those who have had their spleen removed are also more susceptible to severe, but still vaccine-preventable, diseases. 

As far as bacterial diseases are concerned, adults are recommended to take the tetanus toxoid vaccine once every 10 years—starting from childhood—to prevent tetanus. The meningitis vaccine is advisable for those in areas where the incidence of the disease is particularly high; it will not simply protect them, but also their children and the rest of the community. The meningococcal vaccine, meanwhile, protects against four types of meningococcal bacteria—germs that cause meningococcal disease. Similarly, pneumococcus bacteria, which causes pneumonia, can be fought against to a great extent by vaccination. Patients above 65 years of age, those with their spleen removed, or suffering chronic lung or heart disease are all recommended to take this vaccine, given that they are all at risk of catching pneumonia.  

Viral diseases too can be prevented through vaccination. For instance, the influenza virus tends to cause health havoc every winter, and can take severe form, resulting in respiratory distress with increased morbidity and mortality. Taking an influenza vaccine could therefore save us a lot of trouble, as well as benefitting the people around us. We’ve also been hearing time and again about diseases like bird flu and swine flu, and the seasonal vaccine also protects us against these. It can be taken by everyone, and is especially recommended to those who are more prone to recurrent viral respiratory diseases.

 Another viral disease that one can get vaccinated against is Japanese Encephalitis. This is a disease endemic in many parts of our country, where it has caused great morbidity and mortality. Similarly, viral hepatitis resulting in jaundice and liver damage can also be prevented by vaccination. Hepatitis B is generally part of the universal immunisation programme children are subjected to. As adults, however, people should check their protective antibody levels and get a booster if not adequately protected. Hepatitis B is spread by the sharing of intravenous needles and through needle prick injuries from infected individuals, blood transfusion and very close contact with affected individual.  It causes severe liver damage and liver cancer. Another viral disease which needs mention is rubella, a condition all females should be immunised against. Rubella infection during pregnancy produces congenital deformities in the fetus. The childhood immunisation programme does include vaccines for rubella, measles and mumps (MMR), but it can always be taken as an adult if one hasn’t had it before. Yet another viral infection with particular consequences for females is the human papillomavirus, which causes cervical cancer later in life, but thankfully a vaccine is now available to counter it. The elderly population, meanwhile, could suffer herpes zoster virus reactivation, which leads to neurological infections and very painful rashes. Persons above 65 can therefore be given varicella zoster vaccine to prevent this.

Adult vaccination is hence a very useful preventive intervention. Although we cannot advocate it to the extent that we do for children, judicious recommendation in adults with special conditions can be very useful.

Dr Neopane is the Professor of Medicine at the Kathmandu Medical College and a Senior Consultant Physician at the Norvic International Hospital