So CHOP and some other hospitals set up protocols to obtain and test nasal swabs as soon as possible in patients with sudden muscle weakness or paralysis — maximizing their chances of finding the virus if it was there. Sure enough, most patients at CHOP that year had D68 in their respiratory secretions, Hopkins said. And the virus popped up repeatedly elsewhere in the country, though in a handful of cases, patients were found to be infected with a different enterovirus, dubbed A71.