comin a little outa left field here, but a couple old olddd school vets I knew from the bars few years back when that ebola shit was poppin up swore up and down that whole dumping formaldehyde in wells in Africa would 100% mimic ebola symptoms, and leave no traces or at least not that they were gonna test for over there.
wouldn't say if they WERE doing it. but he was pretty certain it worked.