and among the exposure groups, the groups were subdivided as to age and sex as was done in
the initial report.! Control data for both the Rita group and for the Majuro control group ob-
tained during the initial period of observation are shown in Table 4.1. The Rita control values
did not differ appreciably from the Majuro levels and were used for some comparisons with
the exposed population. However, because of the possible effect of the measles epidemic, the
values for the two control groups were not combined. Instead, the Majuro control values alone
were taken as the “normal” for the population in most considerations throughout the report.
From the control data given in Table 4.1, it is seen that the total white and neutrophile
counts were independent of age and sex, that the lymphocyte count was dependent on age but not
on sex, and that the platelet count and hematocrit were dependent on both age and sex. The
values given in Tables 4.2 and 4.3 are presented in accordance with this dependency to allow
valid comparisons. In addition, the total white, neutrophile, monocyte, and eosinophile counts
are presented for ages less than, and greater than, five to allow a comparison of response in
children and adults.
TABLE 4.4~—-Mean Blood Counts for the Exposed and Control Populations, with and without Measles
Rongelap
Determination
With
measles
WEC(in thousands)
Neutrophiles (in thousands)
6.7
4.1
Monocytes (in thousands)
Eosinophiles (in thousands)
Platelets (in thousands)
0.2
0.2
246
Lymphocytes (in thousands)
Hematocrit, %
Control
Without
measles
2.2
-
38.3
With
measles
Without
measles
7.3
4.5
10.7
5.6
9.1
5.0
0.1
0.2
206
0.2
0.6
332.
0.2
0.4
274
38.9
39.2
41.5
2.5
4.3
3.5
, it is apparent from the tables and figures that, while all peripheral blood elements had
shown definite recovery from the peak depression observed earlier, none of the values had returned to control levels at 6 months.
In order to investigate the possible effects of the measles epidemic on the peripheral blood
count, values for those individuals with and without measles were averaged separately (Table
4.4). No significant effect of measles on any of the determinations could be demonstratedin
this manner. Since these averages were taken without regard to the time relation between onset
of symptomsandthe date of the determination, counts were tabulated with relation to onset of
symptoms and averaged. It was not possible, however, to demonstrate changes in any of the
peripheral elements at the time of onset of the disease by this approach.
The results of bone marrow differential counts on exposed and control individuals are
given in Table 4.5. No consistent significant abnormalities were found in the control and exposed groups in the character of the differential count nor in the degree of cellularity or histological structure. In a few instances in both groups of patients, variations in cellular distri-
bution were found which were consistent with systemic infections, such as rubella. These marrows are indicated in the table. Considerable variability in the degree of cellularity was observed, attributable in a large measure to inherent variability in the amountof peripheral blood
in the aspirated marrow specimen.
REFERENCE
1, E, P. Cronkite et al., Study of Response of Human Beings Accidentally Exposed to Significant
Fallout Radiation, Operation Castle final report of Project 4.1.
32