Vulnerable: overexposure to the poliovirus is a key concern with the vaccine

When the vaccine was launched in mid-2005, there was no mention that it was a new vaccine, and therefore no need was felt to examine whether it had been tested

Puliyel had another serious objection. He said administering MOPVI without examining its potential harmful effects amounts to experimentation on human subjects. The question that npsd and who have to answer is why polio drops that are five times more potent, which means they carry five times more of the live poliovirus, was indiscriminately administered. Would this not result in overexposure to the live poliovirus and possibly result in vaccine-induced polio? “The oversight body that introduced this experimental vaccine should also have monitored adverse effects,” wrote Puliyel to Lancet. Further, he mentioned: “In the absence of proper post-vaccination surveillance of adverse effects, we have to rely on indirect evidence of possible adverse effects available from the NPSP. Data from Uttar Pradesh (where Grassly and colleagues show improved vaccine efficacy) show an increase in the incidence of non-polio Acute Flaccid Paralysis (AFP, or the weakness of limbs) since the introduction of the monovalent vaccine.” Doctors in UP are worried about this development. “We want the nature of AFP in these cases to be investigated. It could be due to over exposure to the polio vaccine,” said a senior doctor in Lucknow who has overseen the polio immunisation programme in UP for years.  

These apprehensions are not without reason. Of the 10,264 reported cases of AFP, 209 were cases of polio. Of the remaining 10,055 only 2,553 were followed up. NPSP data reveal that approximately 4,800 cases had residual paralysis or died after acquiring in 2005 non-polio AFP. “The situation was even worse in 2006 after just six doses of MOPVI. It is not surprising that NPSP is not keen on the follow up of these cases,” says Puliyel.

In their reply to Lancet, the study’s authors have ruled out this possibility completely. Interestingly, they cite no study to support their assertion. The increase in AFP cases is attributed to better surveillance and reporting. “The increase in AFP cases began before MOPVI was introduced, and occurred across India, including states where MOPVI has not been used. The introduction of MOPVI is not, therefore, the cause of the increase in cases of AFP,” the authors wrote.

Disagrees Puliyel: “This cannot be ruled out unless tested.” In their reply to Lancet, the authors have written: “Poliomyelitis cases are confirmed only when the poliovirus is identified in the stools of a patient with Acute Flaccid Paralysis (AFP). However, it is impossible to collect stool samples from all such patients.” They have also said: “When we are into the business of polio eradication we are interested in polio and nothing else.”

Jafari said the question of overexposure does not exist. “Each time a vaccine is given, it strengthens the child’s immunity against subsequent doses,” Jafari said. But he failed to explain why infants like Saniya, who have had multiple vaccination, have contracted polio. On the question of whether the rising cases of AFP are a possible fallout of overexposure to polio vaccines, Jafari said, “We know by our 50 years of experience in polio vaccination that the vaccines are safe. There are many studies in place, even in India.” None of these “studies” was quoted in the detailed reply to Lancet.

Then why does polio survive in the Hindi heartland? As usual, the who blames the state government and its poor health infrastructure. Dr LB Prasad, director general of UP’s Directorate of Family Welfare, counters: “Our job is to give vaccines to every child in Uttar Pradesh. We have approximately a 90-percent coverage against the required 80 percent. Each child has received multiple doses.”

Another question is why are local authorities always held responsible for any failure? Did the who care to check the efficacy of its own vaccine? “We are constantly looking at the efficacy aspect of the vaccines,” said Jafari. “That is what led to the introduction of MOPVI.” But if that is the case, why are children, who have been vaccinated more then 20 times, still carrying polio? “The efficacy of the vaccine depends on climate conditions, hygiene, population density, etc. They may not be 100 percent effective,” concedes Jafari. While Jafari does not consider efficacy the real issue, Principal Secretary of the UP’s Health department, Arun Mishra, informed Tehelka: “The efficacy of the MOPVI is being tested by the Indian Council of Medical Research. The results are awaited.”