Clinicoepidemiologic characteristics of scrub typhus and murine typhus: A multi-center study in southern Taiwan

Abstract

Background: This study aimed to offer key features to differentiate scrub typhus (ST) and murine typhus (MT) at the early stage of the diseases and provide clinicoepidemiologic characteristics of ST and MT in southern Taiwan, a region where both diseases are endemic. Comparison of doxycycline treatment efficacy between the two diseases by matching disease severity and delayed treatment had never been investigated. Methods: We reviewed the medical records of cases of ST and MT in four hospitals in southern Taiwan. Propensity-score matching was used to analyze the defervescence curves between patients with doxycycline-treated ST and MT by log-rank test. Results: Between 2004 and 2016, 265 ST and 63 MT cases were diagnosed. The number of cases of ST was significantly related to temperature (Rs = 0.77) and rainfall (Rs = 0.63). Island area exposure, arthropod bite, eschar, and lymphadenopathy were only recorded in ST patients. Multivariate analysis revealed that mountainous area exposure (odds ratio [OR], 11.0; 95% confidence interval [CI], 4.4–27.2) was an independent predictor for ST, while contact with rats (OR, 8.4; 95% CI, 3.3–21.3) was that for MT. After propensity-score matching, there was no difference in defervescence curves between these two rickettsioses treated with doxycycline (p = 0.24). Conclusion: In the present study, island area exposure, arthropod bite, eschar, and lymphadenopathy were unique manifestations of ST. Mountainous area exposure is a predictive factor for ST, while contact with rats predicted MT. There was no difference in defervescence time between these two rickettsioses after doxycycline treatment. Keywords: Rickettsioses, Defervescence, Doxycycline, Propensity score matching