STATISTICAL STUDY OP UNCINARIASIS. 251 



great majority of the white men whom I have been able to study in the 

 Philippines either are or have been in the military service. 



The first work on the occurrence of uncinariasis among American 

 soldiers who had never been outside of the United States, was done by 

 Siler (6) in 1909, when he found that out of 108 southern recruits 93, 

 or 85 per cent, were infected. Following this investigation, I studied 

 the subject among recruits received at Jackson Barracks, near New 

 Orleans, with the result that of the southern-bred recruits- arriving' at 

 that station, 67 per cent were shown to harbor Uncinaria americana 

 (7). Further work proved that among 100 southern-bred 3 soldiers in 

 their first enlistment period (three years) 60 per cent were infected, 

 while among 33 men who had served more than one enlistment, only 11 

 per cent harbored the parasite. All of my cases were very mild infections 

 and did not come from one section, every State in the South being 

 represented. The details are shown in Table IV. 



As this condition had hitherto been overlooked entirely, and con- 

 sequently untreated, it follows that for ten years the Army had been 

 bringing into the Philippines a continuous supply of men infected with 

 the American hookworm. Perhaps we may facetiously call this one of 

 our many ways of "Americanizing" the Islands. Just how many such 

 men have come it is impossible to say, but there must have been several 

 hundred annually. Southern-bred civilian employees of the Army and 

 of the Insular Government have undoubtedly swelled these numbers. 



This importation of uncinaria suggests the interesting question as to 

 whether the United States was the origin of the American hookworm in 

 the Philippines. All the early cases -reported from here were diagnosed 

 as the Old World species (notably Craig's 18 cases (8) referred to later). 

 Eecent reports as to both natives and whites, when they specify species at 

 all, mention only the New "World worm. However, it seems more reason- 

 able to assume that the discrepancy is due to the limited knowledge of 

 uncinaria which was possessed by most physicians ten or twelve years 

 ago. Probably both species existed in the Islands, side by side, from 

 the start, as is found to be the case in Panama (9). 



The majority of the affected American soldiers return to the United 

 States with their regiments in about two years. A few remain behind 

 to fill civil positions and a few are transferred into other regiments just 

 arriving in the Islands. It follows, therefore, that only a small minority 

 of the Americans in the Philippines at any one time are likely to have 



3 The term "southern-bred" in this article refers to those men who were born 

 or had lived for a considerable time in some one or more of the following States : 

 Maryland, Virginia, West Virginia, North Carolina, South Carolina, Georgia, 

 Florida, Alabama, Mississippi, Louisiana, Texas, Kentucky, Tennessee, Arkan- 

 sas, and Missouri. 



