NO. I0 COCKROACHES—ROTH AND WILLIS 75 
Natural vectors—Periplaneta americana, England (Shrewsbury 
and Barson, 1948): Seven strains of Clostridium spp. were isolated 
from the alimentary tract. 
Order ACTINOMYCETALES 
Family MYCOBACTERIACEAE 
Mycobacterium avium Chester 
Common name.—Avian tubercle bacillus. 
Synonymy.—“Tuberkuleznykh kultur (ptichii)” of Pavlovskii. 
Disease —Tuberculosis in chickens, other birds, and less frequently 
in pigs. 
Experimental vectors——Blatta orientalis, U.S.S.R. (Ekzempliar- 
skaia in Pavlovskii, 1948): When fed a culture of M. avium, the 
cockroaches voided the organism in their feces for up to 2 months. 
The organism aparently increased in virulence to guinea pigs by 
passage through the cockroach. 
Mycobacterium lacticola Lehmann and Neumann (?) 
Disease.—The organism gave a slight reaction when inoculated into 
the skin of a guinea pig (Leibovitz, 1951). 
Natural vectors —Periplaneta americana, U.S.A., Texas (Leibovitz, 
1951): Organism, tentatively identified as M. lacticola, was isolated 
from macerated intestines of cockroaches that had been captured in 
sewers. 
Mycobacterium leprae (Armauer-Hansen) Lehmann and Neumann 
Disease.—Hansen’s disease, leprosy. Habitat: Skin of man, leprous 
nodules, nasal mucosa. 
Natural vectors—Blattella germanica, Southern Rhodesia and 
Kenya (Moiser, 1945, 1946, 1946a; Anonymous, 1946): Of 230 
cockroaches, mostly B. germanica, caught in native huts in Rhodesia, 
55 were positive for Hansen’s bacilli. Hansen’s bacilli lasted an aver- 
age of 143 days in the cockroach, though they remained unchanged in 
the feces for much longer, up to 16 months. Moiser observed small, 
acid-fast, oval bodies in about 70 percent of the cockroaches examined. 
Similar bodies have been observed in man, and Moiser thinks that 
they may be a stage in the development of M. leprae in the cockroach. 
Periplaneta americana and Periplaneta australasiae, Formosa (Ari- 
zumi, 1934, 1934a) : Of 67 cockroaches caught in serious-case wards 
in the leprosy sanatorium near Taihoku, 26.8 percent carried M. 
