6 NEW YORK STATE MUSEUM 



been suspected for many years. An active impetus was given to 

 this suspicion through the discovery by Ross that certain Indian 

 mosquitos harbored a malarial parasite affecting birds. It was 

 only a step from this to human malaria. The mosquito-malarial 

 theory took such firm hold that in 1900 Drs Low and Sambon 

 spent the summer on the fever-ridden Roman campagna, relying 

 entirely for protection from malaria upon flimsy mosquito net- 

 ting. Their field test was further confirmed by the shipment of 

 malarial-infected mosquitos to London, where they were allowed 

 to bite Dr Patrick Hanson's son, who in due time came down 

 with the disease though residing in a nonmalarious section. 



The deadly, justly dreaded " yellow jack" has likewise been 

 traced, to its lair through the heroism of a few devoted scientists. 

 Volunteers lived in a fever-stricken locality with no protection 

 from infection other than the frail mosquito bar. They even 

 slept in beds soiled by fever patients for the sake of demonstrat- 

 ing beyond question that the disease was not infectious. Drs 

 Carroll and Lazear went further and allowed themselves to be 

 bitten by infected mosquitos. Both contracted the disease, the 

 latter losing his life on the altar of scientific investigation. This 

 was true heroism. All honor to these martyrs. Theirs was not 

 a useless sacrifice. Before their time, a yellow fever outbreak 

 meant the loss of hundreds or thousands of lives, simply because 

 there was no known adequate method of preventing the disease. 

 Prolonged, arbitrary and wasteful quarantines were maintained. 

 Thousands fled from infected districts. The horrors of the shot- 

 gun quarantine prevailed. The control of the yellow fever epi- 

 demic of 1905 in New Orleans is a most striking testimony to 

 the value of the recent discoveries regarding this disease. This 

 outbreak was handled as a mosquito-borne infection and for the 

 first time the disease was stamped out before cold weather and 

 with comparatively little- loss in either life or property, 



DISEASE CARRIERS 



Typhoid or house fly^ 



The typhoid or house fly is such an extremely common species 

 that a detailed description is almost unnecessary. Dr Howard's 

 investigations show that fully 98;^' of the flies in houses are or- 

 dinary house flies. A few others are associated with this very 



^M 11 sea domestica Linn. 



I 



