SPECIFIC SERUM ANTIBODIES TO INFECTIOUS DISEASE AGENTS IN TARAHUMARA INDIAN ADOLESCENTS OF NORTHWESTERN MEXICO

Abstract

A serologic-epidemiologic survey has been made on serum specimens collected at Sisoguichi in the Sierra Madre Occidentalis of Northwestern Mexico of 50 adolescent Tarahumara Indian boys and 6 adult Tarahumara. Search for evidence of previous contact with, and presumably, present immunity to 17 viruses, 5 rickettsiae, toxoplasma, 17 leptospiral serotypes, the treponeme of syphilis, and 5 bacteria has been conducted by use of tests for 53 specific antibodies, using mouse and tissue culture neutralization, complement-fixation, hemagglutination-inhibition, flocculation, treponemal immobilization, agglutination-lysis, and agglutination procedures. Poliomyelitis antibodies to all 3 types were found in 51 per cent of the adolescents, while 78 per cent had antibodies to type 1, 90 per cent to type 2 and 63 per cent to type 3. Mumps complement-fixing antibody was present in significant titer in 74 per cent of the adolescents, that for herpes simplex in 72 per cent and that for the psittacosislymphogranuloma venereum group in 18 per cent. These results are compared to data in the literature for other population groups. Three of fifty boys had specific complement-fixing antibody to epidemic typhus. Three of the fifty-six subjects studied had specific neutralizing antibody to encephalomyocarditis virus. The significance of this virus as a cause of aseptic meningitis and of other central nervous system disease in childhood is discussed elsewhere in this journal. There the suggestion is made, on the basis of the data summarized, that cases of encephalomyocarditis virus infection may be found in children in the United States once clinicians search for it as the cause of obscure central nervous system infections in young patients. Significant negative results include the absence of evidence for previous contact among these Tarahumara with any of 7 arthropod-borne viruses occurring in North America (EEE, WEE, SLE, VEE, CE, CT, YF), dengue types 1 and 2, lymphocytic choriomeningitis, murine typhus, Rocky Mountain spotted fever, rickettsialpox and Q fever. Only 1 boy had positive leutic serology. Serologic surveys of this type offer the possibility of evaluating the infectious disease problem in a community in which little medical observation has been made and of adding significant new epidemiologic information to data obtained from records of reportable diseases in communities where accurate reporting of infectious diseases has long been the practice.