Vol. 15%,Ne8 jevel was maintsined at 2; 15% ofthe con- Aer this, the platelet count fell, reaching a low of period of observation (10th week). The valves for the lower age group were below those of the older age group fourth week. (At this time counts in 20% of the Ronge- trol valuesfromthe 7th week: to theead oftheerica throughout most of the period of observation. The absolute lymphocyte count(fig. 1) of the older age group had fallen by the third day to a value of approximately 55% of the control value. This value was maintained through~ v ' v u v c ' + v ' ug Ss z v q v T a i: lap people were below 90,000 platelets per cubic millimeter.) The level rose during the fifth and sixth week and hal reached the value noted for the initial counts on the 10th day. A second decrease in platelets developed during the seventh and eighth week, and values remained at ly 70% of the control values during the remainder of the observation period. The pattern of the platelet counts in the male groups was 2 7 ‘similar to that noted for the females. Counts of the lower age group, males, were consistently higher than those of the adult group in absolute county but consistently lower as percentage of control. There was no evidence of hemorrhage into tissues, even though in 11 individuals platelet count levels reached between 35,000 and 65,000 per cubic milli- meter. Two women menstruated when their platelet counts were 150,000 and 130,000 per cubic millimeter ively. Both experienced excessive menstrual » bleeding, insufficient to cause them concern, which sub- ‘cm ACUNOCTTCS, NEUTAOOLES amp LrePnocrTes «0? 30% of the contro! value during the 1 sided without therapy. Six months after the accident, blood cell counts showed only slight increase over previous ones during the last week (10th) of the initial observation period and crik were still below control levels. Follow-up studies at one Oost Curenene oar Fig. t--Meaa leukocyte changes ie highest exposure group (64 people). out the study, with no definite evidence 6f an upward trend. The values for the younger age J T t v ¥ v A v MEAVAO CONTACLS, MALE «10 (8) *or 4 also fell before the third day to a value of approximately 25% MAZUR CONTARLS, FIeat, 1. 063 Be) upward trend, recovery being more rapid fa the younger age group. Sincethe mean lymphocyte counts remained essentially constant throughout thestudy, the fluctuation in total white blood cell count was a re in the neutrophil component (fig. 1). Tho soqutine of derrason of hessopottis are gener ally considered as the major source of morbidity and mortality from whole-body radiation injury. Therefore, in view of the low leukocyte counts that developed in the Rongelap people, the use of administration PLATELETS « 0? of the control value, after which there wasa significant a * ; \ ” ‘ were under continuous medical observation and it was 3} 3 of antibiotics was given careful consideration. Twenty- seven individuals had absolute neutrophil counts of 2,500 per cubic millimeter or less at some time during the period of observation. T depressions as low as 700-1,000 were observed. Prophylactic admininistration of antibiotics was not instituted because all individuals i 0 POST ExPCRURE Bar” Fig. 2.—Measn platelet changes in highest exposure group (64 people). year after the accident showed that the neutrophil counts of the exposed individuals were back to the control level; felt that such drugs might obscure indication of treatment and lead to the developmentof: drug-resistant organisms, An epidemic of upper respiratory infection developed between the 27th and 47th after exposure in all of the exposed groups. Fifty-cight per cent of the Rongelap people were involved. ‘The disease did platelets were still below control levels, though they were higher than after six months. Hematocrit determinations less exposed groups. There was 0 correlation between leukopenia and incidence of infection.: -. - Platelets were first counted -10 days:after exposure shoe epeecee Hept not appear to be more severe in this than in the other (fig. 2), at which time thelevel in the females were ap- proximately 60% of the appropriate control group. however, the lymphocytes, monocytes, eosinophils, and 2. Donkham, C. L.: Cronkite, E. P.; LeRoy, GO. V., and Warren, S.: Atomic Bomb lajary: Radiation, Council oo Natloesl Emergency Med. ical Service, J. A. M. A. 147150 (Sept. 1) 1951. Cronkke, EB. P., and Drociet, OsDetects ie Hemostasis Produced by Whole Body Radiation, ja Clotting and Allled Problema: Transactions of the Fifth Conference,