Polio, once a worldwide scourge, is endemic in just three countries now - Afghanistan, Nigeria and Pakistan. Pictured here is Ameena, a Pakistani girl participating in an anti-polio campaign, showing her ink-marked finger after being vaccinated for polio in Rawalpindi, Pakistan, Monday, October 7, 2013. 
A Pakistani child receives an oral polio vaccine during an anti-polio campaign in Rawalpindi on October 1, 2013. The Polio virus saw a huge surge in year 2011, with as many as 198 cases reported from different parts of the country, forcing the government to enhance the immunization in affected regions. 
Efforts to stamp out the crippling disease have been hampered by resistance from the Taliban, who have banned vaccination teams from some areas. A Pakistani policeman stands guard as a polio vaccination worker marks a child after immunization with anti-polio drops an infant in Lahore on December 21, 2012. 
People attend funeral prayers for victims of an explosion in Peshawar, Pakistan, Monday, October 7, 2013. A bomb exploded next to a van carrying Pakistani security guards tasked with protecting workers involved in an anti-polio drive in the country's northwest on Monday. 
Pakistani polio vaccination workers carry placards during a protest against the killing of their colleagues in Lahore on December 21, 2012. 
Pakistani relatives mourn the killing of a female polio health worker at a hospital following an attack by gunmen in Peshawar on May 28, 2013. 
Pakistani polio vaccination workers shout slogans against the killing of their colleagues during a protest in Karachi on December 19, 2012. The violence prompted UNICEF and WHO to suspend work on a campaign opposed by the Taliban. 
A Pakistani health worker stands in front of a banner at a polio vaccination stall, set up at a bus station, in Rawalpindi on May 31, 2013. The Pakistani Taliban in 2012 banned polio vaccinations in the tribal region of Waziristan, alleging the campaign was a cover for espionage. 
Former Pakistani cricket captain Shahid Afridi chats with a polio-afflicted child during a 'Make A Wish' event in Karachi 18 June, 2011. - Polio has spread to three countries this year
- It's typically the low season for transmission of the virus
- Pakistan, Syria and Cameroon are urged to put measures into place
- 417 cases of polio were reported worldwide in 2013, WHO says
(CNN) -- The spread of polio constitutes an international public health emergency, the World Health Organization declared Monday.
"If unchecked, this situation could result in failure to eradicate globally one of the world's most serious vaccine preventable diseases," the WHO said in a statement.
At the end of 2013, 60% of polio cases resulted from the international spread of the virus, and "there was increasing evidence that adult travelers contributed to the spread," according to the statement.
Polio mainly affects children under the age of 5, according to the WHO. One in 200 infections leads to irreversible paralysis; 5 to 10% of patients die when their breathing muscles become immobilized. It can only be prevented by vaccination.
Of the 10 countries currently infected with polio, three -- Pakistan, Syria and Cameroon -- have allowed the virus to spread internationally, according to an emergency committee convened by the organization, which met late last month.
Polio has spread from Pakistan to Afghanistan, from Syria to Iraq and from Cameroon to Equatorial Guinea, according to the WHO.
The concern is that the spread comes during the low transmission season for polio, typically January through April, said WHO spokeswoman Christine Feig. This is a "red flag," she said, as "it has been years" since the virus was spread to three countries during low season.
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Video games help polio survivor copePolio re-emerged in Syria in October 2013 after a 15-year absence. The ongoing civil war in Syria has hampered immunization rates "due to the severe interruption of public health services and to the conditions in which the people are living," according to a WHO report.
There have been 74 cases of polio so far this year, Dr. Bruce Aylward, WHO assistant director-general for polio, emergencies and country collaboration, said Monday.
Of those, 59 were in Pakistan. No other country has reported more than four cases, and the only country with four was Afghanistan, he said.
The committee's decision to declare an international public health emergency means that Pakistan, Syria and Cameroon are urged to declare national public health emergencies regarding polio and ensure all residents and long-term visitors are vaccinated.
In addition, the WHO said, citizens of those countries traveling internationally should be vaccinated before their departure and carry proof in the form of an International Certificate of Vaccination or Prophylaxis.
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"A coordinated international response is deemed essential to stop this international spread of wild poliovirus and to prevent new spread with the onset of the high transmission season in May/June 2014," according to the organization.
Nations infected with polio, but not spreading the disease internationally now include Afghanistan, Equatorial Guinea, Ethiopia, Iraq, Israel, Somalia and Nigeria, the WHO said. Those nations were also encouraged to take similar measures to ensure high levels of vaccination in residents and travelers.
While the recommendations are not legally binding, they are in the context of the International Health Regulations, which are binding on member states, Aylward said.
"These recommendations are not legally binding in the strict sense ... but they do carry substantial weight because, of course, they are in the context of a legally binding international treaty," Aylward said Monday.
No cases of polio have been detected in Israel, but the WHO previously reported the virus was found in sewage samples, as well as in stool samples from children who had been immunized.
In all, 417 cases of polio were reported worldwide in 2013, said Aylward.
Further spread of the virus could put at risk countries that are currently polio-free but are "conflict-torn and fragile" with compromised routine immunization services, the WHO said.
The current situation is "in stark contrast" to the "near-cessation" of the spread of polio from January 2012 through April 2013, according to the statement.
In March, Southeast Asia, including India, was declared polio-free. India, the world's second most populous country, was able to achieve the goal by deploying immunization efforts to reach those most vulnerable, according to UNICEF.
Polio was eradicated in the United States in 1979, according to the U.S. Centers for Disease Control and Prevention.
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Source : http://www.cnn.com/2014/05/05/health/who-polio/
