A renowned cancer specialist Prof Martin Gore of the UK died recently after a routine yellow fever vaccination.
This has reignited a controversy over vaccines around the world.
What is the yellow fever vaccine?
Yellow fever spreads through mosquitoes. It is often associated with jaundice, and hence the name yellow.
It leads to death in a significant proportion of patients.
So the vaccine is often compulsory before travelling to any of the yellow fever-endemic countries in parts of Africa, and Central and South America.
Known as 17D, the yellow fever vaccine is a live, weakened yellow fever virus.
As it is live, the body responds to it the same way as in a full-blown infection.
This ensures that the body knows the vulnerabilities of that virus for the rest of the person’s life.
Thus, when an invasion happens, blood cells that retain the memory of that virus, work towards defeating the nascent invasion and thus prevent a full-blown infection.
How safe is the vaccine?
The yellow fever vaccine is considered by the World Health Organization as extremely effective, safe and affordable.
A single dose is sufficient to confer sustained immunity and life-long protection against yellow fever disease.
There are, however, reports about multisystem organ failure following vaccination.
There are also reports of individual patient deaths with complications after yellow fever vaccination and of yellow fever after vaccination.
The risk of the vaccine causing serious harm or death is extremely low, but there are complications that may arise.
Among mild problems associated with the vaccine is fever with aches, soreness, redness or swelling where the shot was given.
These occur in up to 1 person out of 4, usually begin soon after the shot, and can last up to a week.
A severe allergic reaction can occur in 1 person in 55,000, and a severe nervous system reaction in 1 in 125,000.
A life-threatening illness with organ failure can happen in 1 person in 250,000, and more than half in the last group die.
What is the complication?
Given the above, vaccine hesitancy is a growing problem the world over.
Recently, the Delhi High Court underlined the importance of parental consent in vaccines given to children in school.
In the US too, states like Minnesota have seen rising vaccine hesitancy, especially among immigrant populations.
Nevertheless, there is evidence available in public health that vaccines provide return for investment.
The resources spent on vaccines are more than recovered in the resources saved by the mortality and morbidity that is prevented throughout the lifetime of an individual.
Is there resistance to vaccines in India?
Resistance to vaccines surfaces periodically.
The diphtheria vaccine is among the oldest in the Universal Immunisation Programme (UIP).
But it has caused the death of 24 children in Delhi in September 2018, and 27 in Nuh district (Haryana) in December.
The Health Ministry has thus commissioned a study on vaccine hesitancy, to be conducted by its Immunisation Technical Support Unit.
