Seroepidemiological Study of Spotted Fever Group Rickettsiae and Identification of a Putative New Species, Rickesttsia sp. Da-1, in Gongliao, Northeast Taiwan

• Published in: Pathogens (Basel) Vol. 10; no. 11; p. 1434
• Main Authors: Yen, Tsai-Ying, Wang, Hsi-Chieh, Chang, Yin-Chao, Su, Chien-Ling, Chang, Shu-Fen, Shu, Pei-Yun, Tsai, Kun-Hsien
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 04.11.2021; MDPI
• Subjects: Age; Antibodies; Arachnids; Dengue fever; Dermacentor auratus; Enzyme-linked immunosorbent assay; Fever; Haemaphysalis; Immunofluorescence; Infections; New species; Parasitic diseases; Pathogens; Residential areas; Rickettsia; Rickettsia sp. Da-1; Risk analysis; Risk factors; Seroepidemiology; Serology; seroprevalence; spotted fever group rickettsiae; Ticks; Tropical diseases; Typhus; Taiwan
• ISSN: 2076-0817; 2076-0817
• DOI: 10.3390/pathogens10111434

Tick-borne spotted fever group (SFG) rickettsioses were neglected in Taiwan. The study reported a seroepidemiological survey of SFG rickettsiae in residents in Gongliao District, Northeast Taiwan. Blood samples were examined for antibodies against SFG rickettsiae by enzyme-linked immunosorbent assay and immunofluorescence assay. Risk factors were assessed using logistic regression. Ticks parasitizing dogs were collected within a 2 km radius from the houses of seropositive participants, and PCR was performed to detect possible tick-borne pathogens. Of 1108 participants, 75 (6.8%) had antibodies against SFG rickettsiae. Residents were more likely to be seropositive if they were older than 65 years, recruited by Dr. Enjoy’s Clinic, or resided in Jilin village. A total of 184 ticks including 5 species (Rhipicephalus sanguineus, Rhipicephalus haemaphysaloides, Dermacentor auratus, Haemaphysalis hystricis, Haemaphysalis ornithophila) were collected. Rickettsia spp. were detected in 6.5% (12/184) of ticks. Rickettsia sp. TwKM01 was found in 6 R. sanguineus and 4 R. haemaphysaloides; while Rickettsia sp. TwKM03 was identified in 1 R. sanguineus. Moreover, gene-based pairwise analysis indicated identification of a putative new species, Rickettsia sp. Da-1, in D. auratus. These findings provided evidence of SFG rickettsiae infection in ticks and suggested SFG rickettsiae exposure in the residents.