Varicella-Zoster Virus Reactivation During the Incubation Period for Scrub Typhus: A Case Report

BACKGROUND Herpes zoster caused by the reactivation of latent varicella-zoster virus is thought to result from the waning of specific cell-mediated immunity. Scrub typhus, an acute infectious disease caused by Orientia tsutsugamushi, affects multiple organs and is characterized by microangiopathies that result in significant vascular leakage and subsequent end-organ injury. Very few cases of reactivation of the varicella-zoster virus following scrub typhus occurrence have been reported. Furthermore, no previous studies have directly investigated whether Orientia tsutsugamushi infection is a potential risk factor for herpes zoster. CASE REPORT We present the case of a 64-year-old woman without a previous illness who simultaneously developed herpes zoster of the thoracic dermatome and scrub typhus. Clinical symptoms of scrub typhus appeared during the treatment course for herpes zoster symptoms. Based on positive virus antibody test results, the patient was diagnosed with scrub typhus. This is a unique case of reactivation of the varicella-zoster virus that occurred during a silent incubation period for scrub typhus. CONCLUSIONS This report indicates the possibility of reactivation of latent varicella-zoster virus following Orientia tsutsugamushi infection, although the relationship between the 2 remains undetermined. Physicians should be aware that scrub typhus might be a potential determinant of varicella-zoster virus reactivation.