INFLUENCE OF PHILIPPINE CLIMATE ON WHITE MEN. 



441 



Leucocyte estimationSj differential counts, and Arneth counts. — The 

 white cell estimations were made with the Thoma-Zeiss blood eotmting 

 instrument, and the differential and Arneth counts after staining films 

 with Wright's stain. The examinations were made only at the end of 

 the observation period of one year, a time when the men had served on 

 the average for about twenty months continuously in the Tropics and 

 in no individual case for less than fourteen months. 



Table XVII.- — Comparative average leucocyte estimations and differential and 

 Arneth counts for blonds and brunettes.'^ 



T.vpe. 



Differential leucocvte count. Arneth count. 

 White ^ 



■ 



Arneth 

 Index. 



""■• ' nnc. ilymph 



l^?n1?.^o^^^- 



Perct. Perct. 

 6.2 3.9 

 6.0 ! 3.8 



Baso- , Class Cla.s.'i Class 

 phile.' t. II. III. 



Perct. 

 0.9 , 11.5 31.6 : 38.2 

 0.8 ■ 14.5 34.5 ; 35.7 



Class 

 IV. 



16.2 

 13.6 



Class 

 V. 



Blond 



Brunette _ 



L_ ... 



1 Perct. ' Perct. 

 6,980 i 54.8 ' 34.3 



7, 155 1 59. 6 i 29. 9 



1 



2.1 



1.8 



43.1 

 49.0 



" These observations were made mostly on the 1910— Group, but some were on the 

 members of the 1909— Group. The leucocyte counts are the average for 89 blonds and 86 

 brunettes ; the differential counts are the average for 45 blonds and 45 brunettes ; the 

 Arneth counts are the average for 28 blonds and 28 brunettes, these being a part of the 

 45 men on whom the differential counts were made. 



That the polymorphonuclear neutrophile count is very low (ranging 

 from 50 to 60 per cent) for Filipinos and for white men with a. year 

 or more of Philippine service has been shown hj Wickline, ( 9 ) Guerrero 

 and Sevilla, ( H ) and by several members of this Board. ( 10) ( 12) Eecently 

 Chamberlain and Vedder(i3) have confirmed the earlier observations and 

 have shown that there is a marked shift to the left in the Arneth count 

 for healthy Filipino laborers and a slight tendency in the same direction 

 for white men residing in the Archipelago. It appears possible that the 

 low count for the polymorphonuclear cells (phagocytes), together with 

 the shift to the left in the Arneth picture (in other words a higher 

 Arneth index), may indicate diminished phagocytic power for the blood 

 in question and a lowered resistance to such infections as are combated 

 in whole or in part by phagocytosis. Applying this theory to the blonds 

 and brunettes it will seem that the evidence from the two methods of 

 counting is conflicting. The percentage of polymorphonuclear neutro- 

 philes is lower for the blonds than for the brunettes,^^ but on the other 

 hand the shift to the left in the Arneth picture is more marked for the 

 brunettes than for the blonds. The difference between the average white 

 cell counts per cubic millimeter for the two types is so slight as. to be 

 unimportant. 



"Wickline, examining soldiers with eighteen months of Philippine service, 

 found the polymorphonuclear cells to constitute 54.3 per cent of the total leucocytes 

 for blonds and 53.1 per cent for brunettes. (9) 



