Seroepidemiology of Infections Due to Spotted Fever Group Rickettsiae and Ehrlichia Species in Military Personnel Exposed in Areas of the United States where Such Infections Are Endemic

• Published in: The Journal of infectious diseases 1995-05, Vol.171 (5), p.1266-1273
• Main Authors: Yevich, Steven J., Sánchez, José L., DeFraites, Robert F., Rives, Cornelia C., Dawson, Jackie E., Uhaa, Iyorlumun J., Johnson, Barbara J. B., Fishbein, Daniel B.
• Format: Article
• Language: English
• Subjects: Acari; Adolescent; Adult; Aged; Antibodies; Antibodies, Bacterial - blood; Bacterial diseases; Biological and medical sciences; Ehrlichia; Ehrlichiosis; Ehrlichiosis - epidemiology; Ehrlichiosis - immunology; Ehrlichiosis - prevention & control; Epidemiology; Female; Fever; Forts; Human bacterial diseases; Humans; Incidence; Infections; Infectious diseases; Insecticides; Ixodidae; Lyme disease; Major Articles; Male; Medical sciences; Middle Aged; Military Personnel; Military training; Permethrin; Prevalence; Prospective Studies; Pyrethrins; Rickettsia; Rickettsia Infections - epidemiology; Rickettsia Infections - immunology; Rickettsia Infections - prevention & control; Rickettsial diseases; Risk Factors; Seroepidemiologic Studies; Ticks; Tropical bacterial diseases; United States - epidemiology
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1093/infdis/171.5.1266

A prospective, seroepidemiologic study of spotted fever group rickettsiae (SFGR) and Ehrlichia infections was done among 1194 US military personnel exposed in a heavily tick-infested area of Arkansas in 1990. Seroconversion (4-fold) and seroprevalence rates were determined by indirect immunofluorescent antibody assays. Seroconversions to SFGR occurred in 30 persons (2.5%), whereas seroconversion to Ehrlichia species occurred in 15 (1.3%). The majority of seroconverters did not report symptoms (22/30 [73%] of SFGR seroconverters; 10/15 [67%] of Ehrlichia species seroconverters). History of tick attachment was associated with seroconversion to SFGR (relative risk [RR] = 4.3, P < .001) and Ehrlichia species (RR = 3.6, P < .05). Use of permethrin-impregnated uniforms significantly decreased risk of infection (P < .01); use of bed nets increased risk by 4-fold. Tickborne infections represent a significant threat to military personnel training in areas in which these infections are endemic.