A quiet, leafy bungalow on the outskirts of the town of Vellore in the southern Indian state of Tamil Nadu has an unusual detail. Near the front door is a hexagonal porthole shaped window with a pattern of thin, white-painted metal bars behind the glass. I paid little attention to the window when I entered the house. It was only as I left that the owner asked me to look closely at it. The metal bars are arranged in the shape of ten interlocking equilateral triangles. “That is the shape of a poliovirus, and if you stand back a bit, you can see it stand out in three dimensions,” Jacob John tells me.
The poliovirus-shaped window bars reflect a life that has been spent trying to exterminate the poliovirus. John, a slim, active man in his eighties, can well claim to be India’s foremost expert on both the disease and the virus. In the late 1960s he ran one of the first studies to understand how many cases of polio there might be in India.
Those early studies were the beginning of a professional career devoted to understanding and studying polio.This career would lead him to sit on World Health Organisation committees, rub shoulders with Albert Sabin and Jonas Salk, conduct vaccine trials in India, and also chair the main expert group advising the polio group in India. But despite this, Jacob John has always been a maverick in the world of polio, and has consistently questioned one of the fundamental articles of faith of the polio campaign. Was OPV, the best tool for polio eradication?
John had used OPV in small trials in Vellore in the late 1960s, but found a significant number of children falling ill with polio despite receiving the three doses of vaccine recommended at the time. Clearly it was not as effective in tropical conditions as Sabin and the WHO thought it would be. John’s confidence in the vaccine was further diminished in 1982 by a WHO study that showed that the oral polio vaccine was paralysing children at the rate of roughly one child (or a close contact of a child who had been vaccinated) for every two million doses of vaccine that was administered. Despite this, the authors of the study concluded that the oral polio vaccine was “one of the safest vaccines in use”.
This description of the oral vaccine as being safe troubled John. “This vaccine can cause paralysis, it can cause hospitalisation. There are only two vaccines that I consider to be unsafe: one is the old rabies vaccine (based on infected neural tissue) and the other is the oral polio vaccine.”
John felt the only reason the WHO study had described OPV as safe was because of Sabin’s influence. “Albert Sabin was a member of the committee that did the study. The wording about it being one of the safest vaccines was his wording. If they had really wanted to look at the vaccine independently, they should not have included him in the committee.” John began a long campaign against the use of OPV, and in favour of the Salk IPV as a better tool to wipe out polio. John was chair of the India Expert Advisory Group on polio eradication (IEAG)—the body that advised the polio campaign and the Indian government on the strategies to be followed to achieve eradication. It is perhaps one of the ironies of polio eradication in India that, in that role, he presided over one of the most intensive uses of OPV in Bihar and Uttar Pradesh the world had seen to date. He took decisions that were successful in the end, but also raised their own ethical concerns.
Crucial decisions were taken between 2004 and 2009 to introduce new monovalent forms of OPV that were more effective than the traditional trivalent vaccine. The aim was also to concentrate on first eliminating the Type 1 poliovirus, which had caused all the big explosions in India to date and spread more aggressively than Type 3.
The new monovalent OPV at first had an almost magical effect in reducing the amount of Type 1 poliovirus transmitting in northern India.The number of cases fell sharply, and the WHO’s polio epidemiologists were cheered by the fact that all these cases seemed to be coming from just two genetic clusters of virus.The greater the genetic diversity of a virus (or any living organism), the harder it is to stamp out. The less the genetic diversity, the more vulnerable it is to extinction. It also looked as though the Type 3 virus, which spreads less easily than Type 1 was about to disappear: only three cases were recorded in 2005, all from Bihar. There was optimism that, within a year, polio could be stamped out from India.
But polioviruses are living organisms that have survived over hundreds of thousands of years by exploiting any opportunity to find new hosts and multiply.
And in 2006, the Type 1 virus found an escape route in the town of Moradabad in western Uttar Pradesh.
The pockets of the town and district where poorer Muslim families lived had been untouched by the bi-monthly vaccination campaigns. They were suspicious of the vaccines and as a result over the years a large number of children had been left either unimmunised or under-immunised. Only about 10 per cent of households had skipped or missed out on polio vaccines. But given the density of population, this still meant tens of thousands of children living in conditions that favoured polio transmission: crowded living conditions and poor sanitation. This was enough for the virus to explode and spread not merely within Uttar Pradesh and Bihar, but to twelve other states.
This explosion of cases, a year after the polio eradication campaign had confidently predicted that the Type 1 virus was on the verge of disappearing, predictably raised questions about the WHO’s strategies and overall competence. It also increased pressure on the Indian government to answer for the rise in cases. Parliamentarians began to raise questions about the effectiveness of the vaccine and the government’s strategy.
“Will the Minister for Health and Family Welfare be pleased to state whether, despite the efforts made by the Government of India under the polio eradication programme, there has been an increase in the number of polio cases during the current year?” This was one typical question asked in May 2006 as polio cases began to rise.The ministerial response typically pushed responsibility to the WHO and stated that the government was only following strategies that the IEAG had suggested.
The only solution, as John, the chair of the IEAG, and the WHO saw it, was to keep hammering away at the Type 1 virus with the monovalent OPV. An essential element of this was trying to reach children in communities that were being missed by polio vaccinators. The epidemiology of polio in India had shown a pattern of explosive outbreaks of Type 1 polio every four years or so.There had been a big explosion in 1998, another one in 2002 and now the same thing had happened in 2006. “I knew that Type 1 came with a predictable regularity, and I predicted the next outbreak would be in 2010, and it was important to prevent that,” John recalled.
Excerpted with permission from Polio: The Odyssey of Eradication, Thomas Abraham, Westland Publications.
