Untreated or incompletely-treated sufferers often have pain in their muscles and joints.

VOA: special.2011.07.26

So, some of these cases were probably due to polio that was transmitted by incompletely killed virus that was present in the vaccine.

因此,那些病例的发病的原因,是被那些疫苗中携带的,没有被完全杀死的病毒感染

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