Benefit of stopping vaccination with OPV

5 May 2008

Here is a question from one of the students in my recent vaccine lecture at Columbia University:

“Isn’t OPV one of the cheapest and easiest to administer? What exactly are the benefits of stopping? Avoiding an isolated case of the disease caused by the administration of the vaccine? It seems like a statistical price that has to be paid for the safety of an entire population, especially since there are still countries with large populations who generally do not have the vaccine available to them. And with worldwide travel…This seems like a disastrous idea. Indeed, the “statistical price” would mean that someone may get the disease but I still think that it is entirely too soon to even consider stopping.”

My response:

OPV is very cheap, cheaper than IPV, to produce. It is also cheaper to administer, but not without cost. The vaccine must be shipped to the intended areas, and kept frozen until use. The latter has been a challenge, as you might imagine, in certain tropical areas. In fact, the WHO developed a portable, kerosene-fired freezer for use in remote tropical areas.

According to WHO, the main benefit of stopping is to allow resources to be spent on other important infectious diseases, such as measles and malaria. To quote them directly: “Once polio has been eradicated, the world will reap substantial financial, as well as humanitarian, dividends due to foregone polio treatment and rehabilitation costs. Depending on national decisions on the future use of polio vaccines, these savings could exceed US$ 1 billion per year.”

There is an excellent recent article in Nature Reviews Microbiology (link) that summarizes very well the argument against stopping vaccination.