Polio - should we give up dream of eradication or not ?

By MARIA CHENG Sunday, March 04, 2007

LONDON - Nearly 20 years ago, the World Health Organization and its partners launched an ambitious program to eradicate polio by the end of the millennium. That deadline passed and another was missed in 2005 _ and polio still strikes about 2,000 people a year, mostly children.At a WHO meeting this week, some leading experts asked a grim question: Is it time to abandon the goal of eradication and focus instead on containing the disease? The answer, for most, was no _ even though many had doubts."Many people wonder why we are spending all this time and effort on polio when there are much bigger problems," said Dr. Donald A. Henderson, who headed WHO's smallpox eradication program in the 1970s. Smallpox is the only disease ever to have been eradicated.There is no question the polio eradication program has reaped rewards: Since it began in 1988, the incidence of the disease has dropped by more than 99 percent. But with the number of polio cases at a virtual standstill for the last five years, some experts worry that the campaign by WHO and its partners _ the U.S. Centers for Disease Control and Prevention, Rotary International and UNICEF _ is running aground.

"Even if things quiet down in the countries where we have problems, there will be another area that bursts into flames," said Dr. Ellie Ehrenfeld, who sits on the WHO Advisory Committee for Polio Eradication."We are living in a different world where I'm not sure what eradication means anymore," said Ehrenfeld, who was not invited to Wednesday's meeting.Critics of the eradication program note smallpox was wiped out in a decade, while the polio campaign is entering its 19th year. WHO is seeking a $575 million budget for polio eradication for 2007-2008.

In a speech to participants, WHO Director-General Dr. Margaret Chan urged participants not to give up."We are facing our best and perhaps our last chance to eradicate polio," she said, adding that leaving the job unfinished would squander the more than $5 billion invested so far because it would open the way for a resurgence of the disease.The four polio-endemic countries _ Afghanistan, India, Nigeria and Pakistan _ are also intent on ridding the world of the virus."We will spare no effort in eradicating polio," said Naresh Dayal of India's Ministry of Health and Welfare. This year, India will spend $286 million to fight the polio virus."While eradication is possible, we shouldn't even consider moving to a control strategy," said Dayal.

Others are not convinced."We cannot continue forever," said Dr. Isao Arita, another WHO smallpox veteran. "Everyone wishes WHO to accomplish the task but there is a limit."For WHO, giving up on eradication would a crushing blow."There's an almost religious conviction that they must see this through," said Dr. Samuel Katz, an infectious diseases specialist at Duke University and co-inventor of the measles vaccine."But there are other things we could do that would be as beneficial to child health rather than spending another billion dollars in frustration," he said.In the countries where polio occurs, there are many competing health priorities, including respiratory and diarrheal diseases, malaria and AIDS.

Some experts say that a polio containment policy wouldn't necessarily be radically different from an eradication policy, except that it would free up money for other health problems.Tighter regulation in countries where polio occurs could help trap the virus, and international officials might adopt measures such as requiring proof of vaccination for travelers coming from polio-endemic countries.WHO and its partners insist it is possible to eradicate polio, and that the only challenges are logistical.Different problems plague the four endemic countries: In Nigeria, the weak health system coupled with a vaccine boycott in some areas gets the blame; in Afghanistan and Pakistan, the virus moves back and forth across the border where the official focus is on the war on terror; in India, children are often infected with other viruses, making the polio vaccine less effective.Some experts think a different vaccine could help. The eradication campaign uses the oral vaccine because it protects entire communities. But while the oral vaccine is cheap and easy to administer, there is a downside: For approximately every 2.5 million doses, it causes one case of polio.WHO is looking into the more expensive injectable polio vaccine, which uses an inactivated virus that cannot trigger polio. Results from the studies won't be available until next year.WHO insists it is considering all options _ except giving up on eradication."Any program would be negligent if it didn't check all the possibilities," said Dr. David Heymann, WHO's top polio official, "but our partners didn't want to hear about a control strategy."

A service of the Associated Press(AP)