Many who have gone through the treatment are able to tolerate accidental exposure to an allergen without reacting.

While the volunteers fed healthy lice, there was still the danger of accidental exposure to some of the typhus-carrying lice in the institute.

The only reported injuries related to iridium concern accidental exposure to radiation from used in brachytherapy.

The seriousness, however, was not realized, with the consequence that the accidental exposure went unnoticed for a number of months.

Any accidental exposure to these viral infections by individuals uncertain of their immunity to chicken pox or measles should be reported immediately as prophylactic immunoglobulin therapy may be administered.