Rickettsial Illnesses as Important Causes of Febrile Illness in Chittagong, Bangladesh

• Main Authors: Hugh W. Kingston, Mosharraf Hossain, Stije Leopold, Tippawan Anantatat, Ampai Tanganuchitcharnchai, Ipsita Sinha, Katherine Plewes, Richard J. Maude, M.A. Hassan Chowdhury, Sujat Paul, Rabiul Alam Mohammed Erfan Uddin, Mohammed Abu Naser Siddiqui, Abu Shahed Zahed, Abdullah Abu Sayeed, Mohammed Habibur Rahman, Anupam Barua, Mohammed Jasim Uddin, Mohammed Abdus Sattar, Arjen M. Dondorp, Stuart D. Blacksell, Nicholas P.J. Day, Aniruddha Ghose, Amir Hossain, Daniel H. Paris
• Format: Article
• Language: English
• Published: Centers for Disease Control and Prevention 2018-04-01
• Series: Emerging Infectious Diseases
• Subjects: Bangladesh; scrub typhus; murine typhus; rickettsia; Orientia tsutsugamushi; Rickettsia typhi
• Online Access: https://wwwnc.cdc.gov/eid/article/24/4/17-0190_article

We conducted a yearlong prospective study of febrile patients admitted to a tertiary referral hospital in Chittagong, Bangladesh, to assess the proportion of patients with rickettsial illnesses and identify the causative pathogens, strain genotypes, and associated seasonality patterns. We diagnosed scrub typhus in 16.8% (70/416) and murine typhus in 5.8% (24/416) of patients; 2 patients had infections attributable to undifferentiated Rickettsia spp. and 2 had DNA sequence–confirmed R. felis infection. Orientia tsutsugamushi genotypes included Karp, Gilliam, Kato, and TA763-like strains, with a prominence of Karp-like strains. Scrub typhus admissions peaked in a biphasic pattern before and after the rainy season, whereas murine typhus more frequently occurred before the rainy season. Death occurred in 4% (18/416) of cases; case-fatality rates were 4% each for scrub typhus (3/70) and murine typhus (1/28). Overall, 23.1% (96/416) of patients had evidence of treatable rickettsial illnesses, providing important evidence toward optimizing empirical treatment strategies.