‘Potent new’ polio vaccine found

Scientists say double-strain vaccine more effective in immunising children against crippling disease in high-risk areas.

india polio vaccination programmes


                           WHO’s Dr Hamid Jafari says the new vaccine has been used in India since the beginning of the year

Scientists in Europe have announced a new and more potent double-strain polio vaccine that is reportedly more effective than triple and single vaccines.

This means children in high-risk areas can be immunised against two important strains of the debilitating disease in a single dose, a study published in the British medical journal Lancet said on Tuesday.

The paper, quoting the World Health Organisation, said research on the bivalent oral polio vaccine found that it induced a “significantly higher immune response” than triple vaccines.

The new oral polio vaccine is effective against Type 1 and 3 poliovirus simultaneously.

Nigel Crawford and Jim Buttery, researchers at Australia’s Murdoch Children’s Research Institute in Melbourne, said the potential effectiveness of the new vaccine was already evident in India, with only 32 cases so far this year compared to 260 in 2009.

Potent weapon

Roland Sutter, a researcher, said the findings showed that the new oral vaccine will be a potent weapon in the battle to eradicate the virus.

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Polio is endemic in Central Asia and outbreaks have also been reported in several African nations [GALLO/GETTY]

“The main advantage of the bivalent is that it is so effective against type 1 and type 3 poliovirus at the same time,” Sutter told the Reuters news agency.

“The impact has been quite dramatic already in India and in Nigeria with cases coming down to very low levels this year.”

The vaccine is made for WHO’s vaccination programmes by various international drug companies including British and Indian firms.

The scientists, in their study between August and December 2008, analysed data from 830 newborn babies from three centres in India.

The infants received either the monovalent, bivalent or trivalent vaccines in two doses – once at birth, the other after 30 days.

Blood samples were then taken at different stages of the vaccination to measure rises in antibody levels. But there were concerns over funding in the wake of the global financial crisis.

Potential effectiveness

Crawford and Buttery, the Lancet study’s authors, said there was a big funding gap for immunisation programmes worldwide which needed to be closed if the aim of eradicating polio is to be met.

“The plan of action for eradication … is only 50 per cent funded for 2010-12,” they wrote in a commentary in the medical journal.

They described the potential of the new bivalent vaccine as “an important step forward” but said “a final concerted effort, both locally and worldwide, is required” to succeed in totally eradicating the virus.

Despite the use of single and triple vaccines, polio is endemic in Afghanistan, India, Nigeria and Pakistan, which countries have reported 153 cases of Types 1 and 3 this year.

There have also been outbreaks in Angola, Chad, the Democratic Republic of Congo, and a suspected outbreak in Sudan.

Many other countries have also had cases of polio so far this year, resulting in a total of 732 cases across the world.

Source: News Agencies