underwent clinical and laboratory examinations in 1956, 1962, and 1971 (Peeler et al., 1958, 1965; White et al., 1974). No members of the study group suffered unexplained clinical symptoms attributable to the vaccination program that required them to take sick leave.
1956 examination (Peeler et al., 1958). At the first examination in 1956, the ages of the 99 Caucasian male subjects ranged from 28 to 65 (with a mean of 40.1 years). All had been vaccinated against botulism, tularemia, Rocky Mountain spotted fever, Q fever, plague, typhus, psittacosis, and eastern, western, and Venezuelan equine encephalitis (referred to as the basic occupational vaccinations); 95 were also vaccinated against smallpox, 37 against brucellosis, 28 against anthrax, and 25 against diphtheria. The initial series of injections was followed by boosters every 6 to 12 months. The duration of the vaccination schedule varied between 8 and 13 years (with a mean of 10.4 years). In addition, these subjects underwent frequent skin tests with a number of antigens (average of 20 skin tests). On average, 2.8 reactions to the vaccinations were recorded per subject (with a range of 0 to 16).
These individuals were evaluated by a review of outpatient and hospital records, complete medical history (n = 93), physical examination at the time of the study (n = 93), and serum electrophoresis and an extensive array of laboratory tests (n = 89). The sera of 44 individuals (18–50 years) who had not undergone multiple vaccinations served as the control group for the electrophoretic studies (controls were not done for the other tests). The controls were not matched on age, gender, or occupational exposure.
The incidence of past illness in the study group was comparable to that of the general population for this age group. Unexplained clinical and laboratory findings at this exam included leukocytosis (n = 20), lymphocytosis (n = 40), and abnormalities in liver function tests (n = 53).
In the serum electrophoretic studies, the mean total serum nitrogen and albumin were significantly higher in the intensively vaccinated group. Also, there was poor separation of α2- and β-globulin fractions in 23 of the subjects but normal separation in the control group. There appeared to be no relationship between the occurrence of this abnormal pattern and the subject’s age, duration of immunization, number of skin tests, or administered antigen amount.
1962 examination (Peeler et al., 1965). In 1962, 76 members of the original study group were available for follow-up. The duration of immunization ranged from 12 to 18 years (with a mean of 15.3 years). In addition to the basic occupational vaccinations, all had been immunized against smallpox, 72 against anthrax, 70 against yellow fever, 66 against Rift Valley fever, 63 against tetanus, 54 against influenza, 37 against poliomyelitis, 34 against brucellosis, 20 against diphtheria, 1 against cholera, and 1 against typhoid–paratyphoid. The number of skin tests varied from 9 to 44 per subject (with an average of 30).
All study subjects were evaluated by a complete medical history, outpatient records, physical examination, serum electrophoresis (also performed in 1958),