GENEVA - A new vaccine against polio, being used for the first time on children in Afghanistan this week, will be critical in the drive to eradicate the crippling virus, the World Health Organisation said on Tuesday.

The bivalent oral polio vaccine, known as bOPV, is made by Europe's biggest drugmaker GlaxoSmithKline, the first of five manufacturers to be licensed, it said.

Some 2.8 million children under the age of five are being inoculated in a three-day campaign which began on Tuesday in the southern and eastern regions of Afghanistan, according to the United Nations health agency.

Because the new vaccine is effective against both types of polio still in circulation, the WHO said: This will vastly simplify the logistics of vaccination in the conflict-affected parts of this country.

The WHO expects the oral vaccine to be a critical new tool in the global eradication initiative and intends to use it on tens of millions of children in India and Nigeria by late January, spokesman Rod Curtis said.

What we have developed with this new bivalent vaccine is the ability to go into a country and to tackle both types of circulating polio virus at once, he told a news briefing.

Panacea Biotec of India has also been licensed to make the new vaccine for future campaigns, with three other drugmakers to follow.

TARGET ELUSIVE
The WHO, UNICEF, Rotary International and the U.S. Centers for Disease Control and Prevention have been working since 1988 to eradicate polio, but their initial target of the year 2000 proved elusive.

Four countries -- Afghanistan, India, Nigeria and Pakistan -- have been unable to stop the spread of polio, which attacks the nervous system and can cause irreversible paralysis.

Access to children in Afghanistan has improved in the past year, but up to 60 percent remain out of reach in Kandahar and Helmand provinces in the south due to insecurity, Curtis said.

Some 31 people have been found to be paralysed by polio in the country this year.

Efforts to eradicate polio in Africa have faced setbacks from the virus spreading out of its northern Nigerian stronghold and causing outbreaks in neighbouring countries that had previously wiped it out.

Fifteen African countries were re-infected from Nigeria in 2008/2009 and polio is still present in four -- Angola, Chad, Democratic Republic of Congo and Sudan -- according to WHO.

But Curtis said the infection rate in Nigeria has fallen dramatically in the past six month, thanks in part to local leaders supporting immunisation campaigns.

Some 386 polio cases have been recorded in Nigeria so far this year, against a total of 798 for last year, he said.

We are very excited about the opportunity in Nigeria that the bivalent vaccine provides, because we have both types circulating, Curtis said.

Pakistan Afghanistan Nigeria India