US: Parkinson's disease has become the latest battleground in the American midterm elections, with right-wing talk radio host Rush Limbaugh locked in an unseemly wrangle with actor and Parkinson's sufferer Michael J Fox.
Limbaugh was forced to apologise to the actor after he accused Fox of exaggerating the symptoms of his illness in an election TV advert. "He's either off his medication or acting. He is an actor after all," Limbaugh said in his broadcast on Monday. Hours later the talkshow host was forced to retract. "I will bigly, hugely admit that I was wrong," he said.
The spat has propelled Fox's 30-second advertisement to the top of the ratings on video-sharing website YouTube, with more than one million viewings in three days. It shows Fox urging voters in Missouri to vote in favour of the Democrat candidate, Claire McCaskill, because of her support for stem cell research, which the actor says is a hope for a cure to his condition.
As he speaks, Fox's body lurches from side to side and his head moves convulsively. "What you do in Missouri matters to millions of Americans. Americans like me," he says.
Despite his apology, Limbaugh returned to the attack on Tuesday. He told his listeners he had uncovered a passage in Fox's book Lucky Man in which he describes forgoing his medication before appearing in front of a Senate subcommittee to highlight the effects of the disease.
Neurologists have said that Fox's chaotic movements were probably a side-effect of the medicines he takes for the disease.