By Tom Watkins
(CNN) -- Health officials announced Friday a campaign to vaccinate more than 20 million children against polio and other diseases across seven Middle Eastern nations and territories.
The announcement, by the World Health Organization and UNICEF, comes a week after an outbreak of polio was confirmed in Syria for the first time since 1999. Ten children have been left paralyzed, and hundreds of thousands are at risk.
"We will expect to see more cases, certainly in Syria if not in surrounding countries," Sonia Bari, a spokeswoman for polio eradication for WHO, said in a telephone interview. She noted that 200 children are estimated to be infected for every case of polio-caused paralysis.
Syria's immunization rates have dropped from more than 90% before the country's civil war began in March 2011 to 68% now, the United Nations Office for the Coordination of Humanitarian Affairs, or OCHA, said Friday in a prepared statement.
Already, vaccinations have been given to more than 650,000 children in Syria, including 116,000 in the northeast province of Deir Ezzor, where the outbreak was confirmed, the OCHA statement said.
The campaign will target Egypt, Iraq, Jordan, Lebanon, Turkey, the West Bank and Gaza.
Over the past year, the poliovirus has been discovered in sewage samples from Egypt, Israel, the West Bank and Gaza, a region that has not seen polio cases for nearly a decade, it said. Transmission of the virus occurs through close person-to-person contact and consumption of food or drink contaminated with feces.
"Preliminary evidence indicates that the poliovirus is of Pakistani origin and is similar to the strain detected in Egypt, Israel, the West Bank and Gaza Strip," the OCHA statement said.
Pakistan is one of three countries -- the others are Nigeria and Afghanistan -- where polio remains endemic.
An emergency immunization campaign is targeting 1.6 million children inside Syria with vaccines against polio, measles, mumps and rubella.
And more than 18,000 children at Zaatari refugee camp in Jordan have been vaccinated over the past few days, with a national goal of reaching 3.5 million people.
In western Iraq, vaccinations have begun, with more planned for the Kurdistan Region in then north in coming days.
The campaign is slated to begin this week across Lebanon, and in Turkey and Egypt by the middle of this month.
Though there is no cure for polio, it can be prevented through vaccination, which is credited with slashing cases around the world by more than 99% since 1988.
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