46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 134 
gens in or on their bodies. There is, however, some question about 
the epidemiological significance of this fact. Most of the evidence 
is circumstantial. The role of cockroaches as intermediate hosts of 
helminths has been established. Although cockroaches undoubtedly 
are vectors of the agents of viral and bacterial diseases, with very few 
exceptions their relations to specific outbreaks of disease have not 
been determined. This area of research has not received the attention 
it deserves. Demonstrating correlations between house flies and inci- 
dence of intestinal disease has been difficult (see Lindsay and Scudder, 
1956). Linking cockroaches with the actual transmission of similar 
disease agents will be no easier. 
Various workers have, as a result of their investigations, expressed 
their concern about cockroaches and disease. Morischita and Tsuchi- 
mochi (1926) stated, “. . . we are led to conclude that the cock- 
roaches commonly found in our island [Formosa] may play a fairly 
important role in the dissemination of infectious diseases and hel- 
minthiasis and must not be overlooked from the sanitary point of 
view.” Tejera (1926) concluded that cockroaches are insects which 
the hygienist must consider as possible disseminating agents of patho- 
genic germs, and, consequently, as transmitters of sickness to man. 
Antonelli (1930) stated that from his investigations he was certain 
that considerable epidemiological importance should be attributed to 
the cockroach which, as a permanent danger, should be fought without 
quarter. Arizumi (1934) stated, “In my opinion the cockroaches, at 
least the two Periplaneta species examined, are eminently apt to 
spread, besides other pathogenic bacilli, also the Leprosis bacillus 
wherever they visit and deposit their feces.” Mackerras and Pope 
(1948) concluded, “We have adduced sufficient evidence to justify 
intensive control measures in any area where both cockroaches and 
Salmonella infections are found.” 
Bitter and Williams (1949) concluded. “Because of the lack of 
conclusive evidence that roaches can transmit disease, these insects 
have been regarded with tolerance by a large portion of the popula- 
tion, especially in areas where roach control is difficult. The results 
cited above suggest that such tolerance is unwarranted and that every 
effort should be made to suppress the cockroach and to protect food 
and kitchen utensils from contact with its feces. Roach control is 
clearly of the highest importance in households that include infants.” 
Graffar and Mertens (1950) stated, ‘““Up to the present time, cock- 
roaches were generally considered repugnant but completely inoffen- 
sive insects. This opinion must be reformed, and it is expedient, in 
the hospitals at least, to waste no effort in destroying them.” Eads 
