LONDON - The World Health Organization claims polio transmission has been stopped in Somalia, leaving only a dozen other countries with the deadly disease.
But given the lack of detailed medical data from Somalia, the absence of a centralized government and continued violence across the country, officials admitted the virus could very easily pop up again.
"Polio could absolutely return to Somalia," said Dr. Bruce Aylward, director of WHO's polio department. "Based on our surveillance, we're pretty confident, but we could still be surprised."
Polio mostly strikes children under five, and is spread when unvaccinated people come into contact with the feces of those with the virus, often through water. It usually attacks the nervous system, causing paralysis, muscular atrophy, deformation and sometimes death.
WHO said Somalia has not reported a case in exactly a year. Last year, the country identified eight cases. Aylward said that WHO has a network of about 100 local Somalis across the country who regularly report any suspected polio cases.
About 10,000 Somali health workers and volunteers were involved in efforts during the past decade to vaccinate nearly every child under the age of five, Aylward said.
Somalia has been ravaged by violence and anarchy since warlords overthrew dictator Mohamed Siad Barre in 1991 and then turned on one another. The current government -- formed with U.N. help in 2004 -- has struggled to assert any real control.
At most, polio paralyzes one out of every 200 children it infects, leading other health officials to suspect that cases might be missed in Somalia.
"I would be very surprised if there were any reliable data at all," said Dr. Donald A. Henderson, who led WHO's smallpox eradication effort in the 1970s. "We can be optimistic, but I think we should also be very cautious."
Henderson also said that without a strong health system in Somalia, reporting polio cases would be extremely difficult.
"If you're the mother of a 10-month-old baby who's suddenly paralyzed, where do you go for this to be reported if there's no health facility?" he asked.
Somalia was declared polio-free in 2002 but the disease was detected again in 2005. Aylward said the country had succeeded this time because of strengthened vaccination campaign strategies, and that the polio strategy could be used to combat other health problems in war-torn areas.
So far in 2008 there have been 191 cases globally, compared with 61 at the same time last year. But only a fraction of the cases have been type 1 polio, which WHO says is the most dangerous and fastest spreading type.
When WHO and partners began their anti-polio campaign in 1988, the worldwide case count was more than 350,000 annually. The disease's incidence has since been slashed by more than 99 percent and remains endemic in four countries: Afghanistan, India, Nigeria and Pakistan.
Polio cases were also detected last year in Angola, Cameroon, Chad, Congo, Myanmar, Nepal, Niger and Sudan.
The health body has missed goals of eradicating the disease globally by 2000 and 2005, and critics have wondered whether the goal is logistically possible.
No new target date for eradication has been set, and the campaign has cost over $4 billion. To continue fighting polio until 2010, WHO estimates that another $525 million is needed.
