NEWS ANALYSIS. Of conspiracy, bio-terrorism and a ‘contaminated’ polio vaccine

From conspiracy theories to bio-terrorism concerns, mystery shrouds the recent emergence of the type 2 strain of polio virus in Uttar Pradesh, and its alleged link to “contaminated” vaccines.

The type 2 strain had shown up in sewage and stool samples taken during surveillance and had become a cause of concern for the Centre, especially since this type had long been eradicated globally.

Investigations directed by the Health Ministry put Ghaziabad-based Bio-Med Pvt Ltd in the dock, as it had supplied the polio vaccines and a few vials were found to have traces of the type 2 strain. Later this month, health experts are set to visit Indonesia’s Bio Farma that supplied the bulk vaccine to the Indian firm. This, even as the Bio-Med top brass in India reportedly refute the contamination allegation.

Keeping a close watch on the developing situation, doctors allay fears that the incident could cause an outbreak of sorts. The “contaminated” vaccine was an “attenuated” one containing the “weakened” virus, says one doctor. However, questions remain on the source of this polio Type 2 virus, say paediatricians.

And the reason for their concern is this. Since April 2016, all polio and routine immunisation programmes in India are using inactivated poliovirus vaccine (IPV) and bivalent oral polio vaccine (bOPV), against the earlier trivalent oral polio vaccine (tOPV). The switch was undertaken after certification of the global eradication of type 2 wild polio virus. In fact, the last type 2 wild polio virus case was detected here in 1999, says a Health Ministry note.

Call for transparency

Advising abundant caution, one paediatrician calls for greater transparency in communicating the developments around this incident.

Otherwise, it gives rise to unfounded fears that upset the use of established vaccines in immunisation, he says. Knowing the source of the type 2 polio virus is also critical, as countries such as Pakistan, Afghanistan and Nigeria are yet to become polio-free.

Besides, there are regions in the world dealing with a resurgence of polio or similar illnesses. An outbreak of vaccine-derived polio type 2 virus was reported in Congo earlier this year. And, more recently, the US is monitoring what reports call a “polio-like” illness.

Though India was certified polio-free in March 2014, vigilance continues on all three types of polio viruses. The last polio case due to wild polio virus (type 1) in the country was detected on January 13, 2011.

Dr Naveen Thacker, recently elected as the Executive Director of the International Paediatric Association, says it is unlikely that India’s polio-free status will be affected by the recent finding of type 2 polio virus.

There is technology available to understand how long the virus circulates and any new cases would have been detected by now, he told BusinessLine .

Misinformation worries

But Thacker is concerned over the misinformation on the incident and more generally, even on regular vaccines and immunisation. He cautions against “bio-terrorism” and efforts that could be under way to destabilise India’s health programmes. A case in point, he says, are social media messages that fan fears against basic vaccination.

Another medical expert wonders if there is more to it than meets the eye. Did the surveillance reports pick up wild polio Type 2 virus occurring naturally, which could be an “embarrassment” at a time the country prides itself on its “zero polio status”? And so, was the vaccine-derived polio version being explored as a “face saving measure” of sorts? Or, are there people trying to nudge the Government to go fully with injectable vaccines (as opposed to oral ones), that are more expensive, asks the expert.

As the Centre ups surveillance and the mop-up vaccination of children, the controversy over the Type 2 polio virus occurrence is one it will have to clear up quickly to keep the already fragile trust in vaccines.

COMMENT NOW