Although a viral etiology has been suggested for recurrent aphthous stomatitis,1 most investigators have not been able to isolate a virus from recurrent aphthous lesions.2 Some investigators, however, have reported that patients with recurrent aphthous stomatitis were benefited by vaccination with smallpox vaccine3 and particularly by the use of intradermal injections of smallpox vaccine.4 This study was attempted in an effort to corroborate the latter positive findings.
Each patient presented had a history of recurrent aphthous stomatitis of at least one year's duration (many much longer) and had been observed by us for a prolonged period during the course of placebo and other unsuccessful therapy, some phases of which have already been reported.5 In no case was any evidence of accompanying skin lesions noted.
METHODS
Five intradermal injections of smallpox vaccine were administered to each of the 12 patients (four men and eight women,