Table 4.7) ALLINGINAR GHOUP MEAN BLOOD COUNTS AT CTIME OF PEAK DE PIE SSION Case No. W.B.C. Platelets * 10 Neutrophiles Ly iiphooytes (Average from Diy 9 to 41) (Average trom Duy 26 to 40) (Average from Day a to Shi Average Grom Lhav ish tar ood) —_— ti 4 44 - ~ — r Age Less Than 5 9750 21s 4570 180 xnho all KI G20 6170 4700 i. 1 Dh 3470 4G00 2350 ag 4820 duoe Ane 6 lo LS Aw oS i ro ht i- re “10 970 240 240 3150 A700 waa noo 21d0 tao. r Eo f Age Greater Thin bo t 16 2H 29 31 4] 4570 2200 3720 4100 2950 3050 2370 2270 w270 2220 2450 2270 140 4170 1470 170 105 4620 4120 6150 215 5u 7050 95 51 99 r 178 195 115 115 145 110 43 45 70 4.5 6170 4GTO 6270 6750 565U SL2U 5650 7750 12400 5070 . 3700 2970 185s 4000 RONGELAP GROUP . iv [ 2000 f 2900 I 2950 3670 i 1750 _ The absolute neutrophile count of both the younger and older age groups fell during the second week fo u value, approximately 70 to 80 per cent of that of the controls (see Fig. 4.1). Following the depression of the total neutrophile count during the second week, the values were unstable until the fifth week. Alt this time the beginning of a second drop (P < 0.01) was noted for both age groups, and a low value of approximately 50 per cent of controls was reached, The count was maintained al approximately 75 per cent of control values from the seventh week to a i 7 ro the end of the study. Although both age groups followed the same general time pattern of response, the lower age group was below that of the older group throughout most of the observation period, The absolute lymphocyte count of the older age group (Fig. 4.2) had fallen by the third day to a value approximately 55 per cent of the control group. This value was maintained throughout the study, and there was no definite evidence of an upward trend during the study. The values for the younger age group likewise fell before the third day to a value approximately 25 lymphocyte count, there is a consistent difference between the two age groups. However, during the first four weeks the difference {s accentuated when expressed as per cent decrease because of the relatively high lymphocyte levels in the lower age control group. After this period the differences expressed as per cent are less marked since recovery was more rapid in the younger age group, The cellular elements chiefly responsible for the fluctuations in total white blood cell 4 4 ’ * 79 re eee - ee ee count can be determined by comparing the total white, neutrophile and lymphocyte counts (Fig. 4.3). It is seen that the lymphocyte count remained essentially constant throughout the period of study, while the total neutrophile count fluctuated with a pattern essentially identical to that aa per cent of the control, following which there was a significant upward trend. With the total