352 Microbes and You 



rapidly than might normally be expected had the eggs been absent. 

 Surgeons in the army of Napoleon confirmed this early report. 

 Further support was given this finding during World War I when 

 men who had been left on the battlefield for several days without 

 medical attention were found to harbor maggots in their wounds. 

 Oddly enough, however, many of these individuals had no fever 

 and their dressed wounds healed very quickly. Pus and debris 

 were absent in the wounds, and the underlying tissues were pink 

 and healthy in appearance. Subsequent investigations conducted 

 on maggots have revealed the presence of a thermostable bacteri- 

 cidal substance in their excretions. This substance is particularly 

 active against staphylococci, streptococci, and the organisms ( Clos- 

 tridium perfringens) responsible for gas gangrene. After the first 

 World War cases of osteomyelitis (a bone disease) were com- 

 monly treated with maggots which devoured the dead tissue, de- 

 stroyed the bacteria, and kept the wounds clean. With the advent 

 of the sulfa drugs and later the antibiotics, the use of maggots has 

 been discontinued. 



COCKROACHES 



The cockroach has long been suspected of harboring and dis- 

 seminating disease organisms. Relatively little work, however, 

 has been done to implicate these insects as definite vectors of dis- 

 ease. The filthy habits and cursorial nature of roaches makes them 

 ideally suited for the mechanical spread of certain pathogenic 

 organisms by contamination of foodstuffs and fomites through con- 

 tact with the infected appendages of the roach. 



A number of reports have been published, including those of 

 Mackerras and Mackerras (1948) and Bitter and Williams (1949), 

 indicating that enteric pathogens belonging to the genus Salmonella 

 may be excreted by roaches under certain circumstances. Should 

 these roaches gain access to food to be consumed by humans, 

 infections with these enteric pathogens might well take place. 

 Janssen et al. in 1952 reported that feeding massive doses of Sal- 

 monella typhosa to the roach Blattella germanica resulted in no 

 excretion of these organisms after a twenty-four-hour period. In 

 fact, it was impossible to isolate the typhoid organism from the 



