题目内容：
their strong desire to solve compler pohleneundamental human urge to diplay their Iramed kelh
Passage Flve polio in 2005. iohe W.H.O. says more than one thouend children hove leen infeted in 205s That e moer hom Inalio began to spread in 2003 when immuniation(免疫接种）campore e trped ir eroa AISa E SV RLBN LOLN poln.There are several hundred new cases in Yenen.children under age three suffer more than half of all cases of polio,The virnw is preard throgh eaer human waste.The vinus enters the mouth and inveades the nevous syuerm The W.H O.ay mo rouple who are infected never show signs of polio.But they can spred the vins for wveral wrerke The W.H.O.says one out of two hundred infections leads to paralysis that never goes awae.Leually the victims lose the ability to move their legs.Some lose control of their breathing muscles and die.
People who recover from polio can suffer additional muscle weakness and other disorders
years er.Doctors call it post-polio syndrome(综合征）。There are no cures for polio,but it can be prevented.Indonesia has plans for national immunization campaigns on August thirtieth and September twenty-seventh.The goal is to vaccinate more than twenty- four million children under age five.
51.Why did the polio virus spread to a number of African countries again?
A.Because immunization campaigns were stopped for a year in northern Nigeria.
B.Because the W.H.O.di
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