Vaccine-related polio a ticking time bomb in S India

While lauding South India for its better polio control and routine immunisation records, officials have cautioned that the four southern states also stand a higher chance of contracting vaccine-related paralytic polio (VAPP) which, if not checked in time, may trigger into a major public health crisis.

“Southern states have achieved better polio control and have better track record on immunisation. That’s why they are at a higher risk of VAPP. If VAPP cases become more than the wild, it is unacceptable. That’s why it is the right time to introduce inactivated (and injectable) polio vaccine (IPV) in South,” Panna Chaudhry, former president of the Indian Academy of Paediatrics, told Deccan Herald.

VAPP is an accepted risk in the polio campaign. As long as the virus is alive and kicking in the wild, it is not a worry. But when the wild strain is under control, it’s vital to check VAPP so that it does not snowball into a crisis.

Though this year, the government has been able to keep the wild polio cases under check with reasonable success using OPV, doctors say it’s time to think about VAPP and vaccine-derived polio cases and how  IPV could make a difference.

OPV is a live but weakened virus given as drops to children. IPV contains killed or inactivated virus which is injected into the infant and is expensive.

“A strategy shift from OPV to IPV will avoid inevitable problems associated with OPV such as vaccine-associated polio, risk of polio in immunocompromised children and risk of vaccine derived polio outbreaks that have occurred in some countries even after successful eradication of wild polio,” said T Jacob John, member of the Global Advisory Polio Eradication Committee, WHO, and former head of Clinical Virology at the Christian Medical College in Vellore.

However, IPV should be given only after feasibility studies have been conducted in a few districts because a single failure in injection can turn into a bottleneck for the entire campaign, said A K Dutta, veteran paediatrician at Kalawati Saran Hospital, here. “The road ahead is challenging as we have to sustain the success,” said Union Health Secretary K Sujatha Rao.

According to the WHO, a nation cannot be declared polio-free unless there are no fresh cases reported for three consecutive years. India has already extended the deadline three times. For instance, in 2005, India reported success, but things went horribly wrong in the very next session. The polio situation in the country has also become complicated with the return of P2 starin via the vaccine route.

In the last two years, as many as 21 vaccine-derived P2 polio cases were reported even though the virus was supposed to have been eliminated from the country more than 10 years ago. “This P2 is only vaccine-derived. Its not a matter of great concern. More worrisome is our failure to control P3,” said Dutta.