Seroprevalence of tetanus antibodies among immigrants over age 50: A comparison to an aged matched US-born population

Abstract

Study objectives: A significant number of elderly patients and immigrants have been documented to have nonprotective titers to tetanus. In 1995, the Advisory Committee of Immunization Practices recommended that all patients aged 50 years and older be evaluated for tetanus immunization. This study is to define the extent of immunity against tetanus antibodies among patients older than 50 years by measuring antitetanus antibody (ATA) levels and whether the patients were born in the United States. Methods: A convenience sample of 103 ambulatory patients was studied. Serum was obtained, and enzyme-linked immunosorbent assay testing was performed using the Bindazyme (Binding Site Kit, San Diego, CA). Results: In 56 (54%) of 103 study patients, ATA levels did not reach protective levels. Forty-three (73%) of 50 women and 13 (30%) of 44 men did not have adequate titers. Fifty-five (53%) patients were immigrants, and 46 (84%) of 55 did not have protective titers. Ten (21%) of 48 of US-born individuals older than 50 years did not have protective ATA (<i>P</i><.001). Conclusion: Patients older than 50 years are substantially less likely to have adequate immunity to tetanus, especially if they are not born in the United States. Emergency physicians must take this into consideration when evaluating tetanus immunization status in injured patients older than 50 years.