Table 2 Summaryof Positive Serologic Tests for Hepatitis B Surface Antigen (HBsAg), Antibody to Surface Antigen, and Antibody to Core AntigenAmong 314 Marshallese Number Tested By sex Male Female Combined By age (yr) < 29 ‘29-49 > 49 HBsAg Positive 134 180 314 123 (91.8)* 165 (91.7) 288 (91.7) 20 (14.9) 16 ¢ 8.9) 36 (11.5) 46 175 93 43 (93.5) 158 (90.3) 87 (93.3) 3 ( 6.5) 20 (11.4) 13 (14.0) Byatoll of residence ** Kwajalein Majuro Rongelap Utirik 100 74 61 76 By radiation exposure group Rongelap exposed Utink exposed Rongelap comparison 61 112 95 By atoll of residence, excluding Rongelap exposed Ebeye Majuro Rongelap Utink One or More Positive Tests 89 68 58 70 . 69 61 44 76 (89.0) (91.9) (95.1) (92.1) 50 (82.0) 103 (92.0) 86 (90.5) 63 58 42 70 (91.3) (95.1) (95.5) (92.1) 10 4 3 19 (10.0) ( 6.4) ( 8.5) (25.0) 2 ( 3.3) 21 (18.8) 10 (10.5) 6 4 3 19 ( 8.7) ( 6.6) ( 6.8) (25.0) * Percent of the total population tested is shown in parentheses. ** Three persons resided outside the atolls listed. Table 3 Skin Test Responsiveness by Radiation Exposure Group* Radiation Category Rongelap Utirik Comparison ‘No. in Each Category 62 137 135 No. Tested 38 72 68 Tuberculin Negative Candida Negative 16 (42.1%) 39 (54.2%) 35 (51.5%) 2 (5.3%)** 0 (0.0%) 2 (2.9%) * See text for definition of positive and negative tests. ** Two persons, an 83-year-old Rongelap exposed man and a 43-year-old unexposed woman, had positive tuberculin tests despite negative reactions to Candida antigen.