Changes in the Seroprevalence of Tick-Borne Rickettsia and Ehrlichia Among Soldiers—Fort Liberty, North Carolina, 1991–2019.

This article focuses on temporal trends in seroprevalence of tick-borne pathogens Rickettsia and Ehrlichia among soldiers stationed at Fort Liberty, North Carolina, from 1991 to 2019. Analysis of serum samples from the Department of Defense Serum Repository revealed a significant decrease in antibodies to spotted fever group Rickettsia (SFGR) over time, while seroprevalence of Ehrlichia antibodies nearly doubled, likely reflecting increased exposure due to the expanding geographic range of the lone star tick (Amblyomma americanum). The study highlights that nearly 19% of soldiers showed evidence of prior exposure to these pathogens, with regional and demographic factors influencing seropositivity. Limitations include the predominantly young male military population and inability to determine exact timing or location of exposure. The findings suggest a need for targeted interventions to control lone star tick populations and improve awareness of ehrlichiosis risk.