17< ANNUM. ItEPOIt'f ( >l r TIIK "IT Dor 



A NEW DEPARTMENT. 



By an act of the Legislature of 1905, the new Department of Health 

 of the State of Pennsylvania was created. This Department is under 

 the direction of Dr. Samuel C. Dixon. Dr. Dixon has a local repre 

 sentative in every county, town and city in the State, whose duties 

 are to prevent the spread of contagious and infectious diseases. 

 We think this Board should lend its influence to this new Depart- 

 ment, and to Dr. Dixon, in its effort to frustrate and stamp out these 

 diseases in this State, especially because the spread of these dis- 

 eases is often directly or indirectly traceable to the farm, and if not 

 so traceable, the farm is usually blamed for the infection and con- 

 tagion. 



Insects play no small part in this infection because they can 

 either act as mechanical carriers of these germs, or as an inter- 

 mediate host, or a necessary element in the life cycle of the dis- 

 ease germ. 



One of the commonest and most frequent is the carrying of typhoid 

 fever germs by flies. The bacilli, which are found in the excreta 

 about the premises where typhoid fever has prevailed, adhere to the 

 feet of the flies and are carried in the next flight to a dish of food al- 

 lowed to remain exposed in the culinary department of the house, 

 or a milk pail, or even to the dinner table. By means of the food, 

 the germ will gain entrance with the elementary canal often with 

 disastrous results. This has been fully demonstrated in the army 

 camps of the Spanish American war. But typhoid bacilli are not 

 the only ones transported in this way, but well nigh conclusive evi- 

 dence is on hand that the germs of Cholera, Erysipelas, Tuberculosis 

 and Bubonic Plague have been carried in this way. Neither are 

 flies the only carriers, but other blood sucking insects, such as mo* 

 quitos, bed-bugs, flees, etc. 



Not only do these insects carry disease germs by adherence to 

 the external parts of their bodies, but experiments have shown that 

 various bacilli may pass unharmed through the intestine of the fly 

 and be recovered in the ejections of these insects. This is not only 

 true of bacilli but eggs of such parasites as the tape and round 

 worms, have been found unaltered in the droppings of flies. I have 

 already intimated that insects are frequently an intermediate host 

 or a necessary element in the life cycle of disease germs. Thus the 

 embryonic round worm in the human blood must be drawn into the 

 stomach of the mosquito, wander out into the thoracic muscles and 

 grow to a definite stage of development before they can again enter 

 the human host and become sexually mature adults which pro- 

 duce the blood inhabiting embryos. 



In case of Malaria, the germ must be drawn up into the stomach 

 of the anapheles mosquito and within its body undergo a complicated 

 series of changes before the new generation is ready to be injected 

 into the human blood, where they produce a new case of Malaria. 

 The biting insect is not only an essential, but it is equally necessary 

 that the organism pass through the changes in the mosquito before 

 it can infect. This has possibly been more clearly shown last sum- 

 mer in the Yellow Fever Epidemic at New Orleans. It was shown 

 that a specific type of mosquito (Stegomyia fasciata) designated often 

 as the Yellow Fever Mosquito, transmits this disease. This mos 

 qnito aoqiiirfs this power by feeding on tho blood of a Yellow Fovor 



