Polio cases in Bihar declined by 94 percent

Polio health workers went on their usual trot last year, moving door to door in affected areas, administering drops and marking their visits in chalk.

Without any seeming difference in their ritual, they brought down the count of new cases of polio in the country to its lowest ever.

India reported 41 new cases of the crippling disease in 2010, a 94% drop over the previous year.

That’s nearly a repeat of 2005, when only 66 new cases of polio were reported. But the two-digit count could not be sustained and it shot up to 676 the following year.

This time, though, health experts say the country may have found a way to keep the number low. The difference in 2010 lay in the drops.

Polio virus type 2 (PV2) was eradicated years ago, but two other strains—PV1 and PV3— have proved stubborn. PV1 is a more severe strain of the virus, while PV3 is more common and spreads rapidly.

In January 2010, the Union government launched a bi-valent oral polio vaccine (bOPV; it attacks PV1 and PV3 strains) in the hope that it would work better than the tri-valent (attacks all three strains) and mono-valent vaccines (attacks single strain).

“The bivalent oral polio vaccine (bOPV), which was first developed and tested in India, has proved to be very effective. The impact of this new tool has been impressive against both remaining polio virus types 1 and 3,” said Hamid Jafari, project manager, World Health Organisation (WHO)-National Polio Surveillance Project (NPSP).

Even Uttar Pradesh (UP) and Bihar, which have struggled to contain the virus, have reported a significant decline in new polio cases, with UP not reporting a single new case of the deadly PV1.

“Recent immunity studies among infants in high-risk areas of UP and Bihar have demonstrated that the bOPV is providing protection levels against both virus types that are similar to those achieved by each of the respective monovalent oral polio vaccines. The programme has evolved…,” said Jafari.

Advocacy for and the final launch of bOPV in India was facilitated by the Bill and Melinda Gates Foundation following the success of the vaccine in Europe. It was already being recommended by WHO as well.

In 2007, the foundation, along with the government, WHO and Rotary International, conducted a study in India comparing bOPV with the earlier vaccines. The results were encouraging.

Soon after, the Gates Foundation began discussions with Indian vaccine makers to help produce bOPVs at lower costs. “India saved nearly $600 million (Rs.2,688 crore) in vaccine purchase because the Gates Foundation helped in bringing down the cost of the vaccine by talking to manufacturers,” said a person who works closely with the polio eradication programme. He didn’t want to be named.

Delhi-based Panacea Biotec alone supplied around 700 million doses of oral polio vaccines in 2010 to the government and the United Nations Children’s Fund (Unicef) of which at least 40% were bOPVs. “Development of any new vaccine is a costly affair. However, pricing of bOPV was kept (with) affordability in mind,” said Rajesh Jain, joint managing director, Panacea.

The Gates Foundation also helped in assuring manufacturers of an uptake for the new vaccine. “There were several recommendations made suggesting that the vaccine of choice was bOPV and not mOPV. India should be very optimistic now, with 2010 showing such commendable results,” said Linda Venczel, in-charge, Polio Programme, Gates Foundation.

The 2010 results have raised expectations for manufacturers as well. Demand for bOPV “would be substantial as its large-scale use in supplementary immunization activities would complement the continued use of tOPV and mOPVs”, said Jain.

Despite the optimism, polio eradication in India still faces enormous challenges. The success of bOPVs was largely aided by improved immunisation campaigns in Bihar and UP, cooperation from various religious communities and greater awareness of the disease. But other states are emerging as new centres for polio—West Bengal, Punjab, Delhi and to some extent Maharashtra.

“Mass-scale migrant and mobile population in these states is leading to the spread of polio. A lot of these families aren’t administered the polio drops in their villages because they have either migrated or aren’t in their homes when the health workers visit,” said Manjit Sawhney of Rotary International and a member of the NPSP team.

“The biggest risk would be complacency at this juncture, which could reverse the progress achieved. It is essential to keep Uttar Pradesh and Bihar polio free, maintain the intensity of the programme and reach all children of migrants and be prepared to rapidly and effectively respond to detection of any wild polio virus anywhere in the country,” said Jafari.