Challenges of mass vaccination
One of the barriers to the successful implementation of the National Smallpox Eradication Program was the quality of the vaccine and the method of delivery. Because of the World Health Organization’s partnership, India was able to acquire higher quality freeze-dried vaccines. Concurrently, the quality of vaccine manufactured within India also improved.
More problematic was the method of vaccination. Prior to 1969, the standard method of smallpox vaccination was to place a drop of vaccine on the patient’s arm and press it into the skin with a single-point needle. This process was repeated five times for a primary vaccination and fifteen times for a revaccination. Much vaccine was wasted and it was difficult for workers to perform correctly. The jet injector was an improvement over the single-point needle and didn’t require electricity. However, the device required frequent maintenance and was prone to breakdown in the field. (Tucker 71)
The introduction of a multiple puncture technique, utilizing a bifurcated needle, had immediate positive consequences. The bifurcated needle was a cheaper and easier method of delivery. Healthcare workers needed minimal training. It was also less painful and less traumatic for the patients.
Aside from vaccine quality and the use of bifurcated needles, India had another barrier to successful mass vaccination. In most countries, vaccinating 80 percent of the population over a five-year period was considered sufficient to interrupt smallpox transmission. (Tucker 75) However, in densely populated countries such as India, the large number of births every year (25 million new Indian babies) made this target impractical. Mass vaccination could only reduce the incidence of smallpox; it couldn’t contain it. A new strategy was needed to augment the vaccination efforts: the “surveillance-containment” search.
Smallpox in India, pre-1972
Surveillance-containment searching