Results of inoculation of white rats with human leprosy bacilli by the intraneural route preliminary report

ABSTRACT

1 An attempt has been made to transmit the human leprosy bacillus to white rats by injecting the exposed sciatic nerve with a suspension of bacillus-rich leprous tissue mixed with an equal amount of sterile egg albumen. 2- One of the five rats so inoculated showed evidence of massive infection with an acid-fast organism whem sacrified three and one-half months after inoculation. In an attempt to ascertain the actual nature of this acid-fast organism, material from this rat was passed by intraperitoneal inoculation to other rats and to guinea-pigs; and a second similar passage has been made, too recently for the results to be known, to rats and mice from lesions which developed in one of the first-passage rats. 3- Negative results of cultures and of the guinea-pig inoculations indicate that the acid-fast bacillus encountered is not the tubercle bacillus or any other readily-cultivated mycobacterium. The occurrence of an infection by acid-fast bacilli in the rat of the first passage group which survived sufficiently long suggest that the bacillus may be the Stefansky bacillus and not the human leprosy bacillus. 4- This observation brings out the great importance of excluding chance infection with Stefansky bacillus of rodents inoculated experimentally with human leprosy material, especially in laboratories where work with both human and rat leprosy is being carried out.