Open Access
Research (Published online: 11-08-2023)
4. Seroprevalence of Orientia tsutsugamushi and Rickettsia typhi in water buffaloes (Bubalus bubalis) from Southern Thailand
Decha Pangjai, Phirabhat Saengsawang, Kamchai Kidsin, Ngamchit Choongkittaworn, Yukio Morita, and Sumalee Boonmar
Veterinary World, 16(8): 1600-1604

Decha Pangjai: Department of Medical Sciences, National Institute of Health, Ministry of Public Health, Nonthaburi 11000, Thailand.
Phirabhat Saengsawang: Akkhraratchakumari Veterinary College, Walailak University, Nakhon Si Thammarat, 80160, Thailand; One Health Research Center, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
Kamchai Kidsin: Animal Health Section, The Eight Regional Livestock Development, Surat Thani 84000, Thailand.
Ngamchit Choongkittaworn: Akkhraratchakumari Veterinary College, Walailak University, Nakhon Si Thammarat, 80160, Thailand; One Health Research Center, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
Yukio Morita: Department of Veterinary Medicine, School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5201, Japan.
Sumalee Boonmar: Akkhraratchakumari Veterinary College, Walailak University, Nakhon Si Thammarat, 80160, Thailand; One Health Research Center, Walailak University, Nakhon Si Thammarat, 80160, Thailand.

doi: 10.14202/vetworld.2023.1600-1604

Article history: Received: 05-04-2023, Accepted: 06-07-2023, Published online: 11-08-2023

Corresponding author: Sumalee Boonmar

E-mail: sumalee.bo@wu.ac.th

Citation: Pangjai D, Saengsawang P, Kidsin K, Choongkittaworn N, Morita Y, and Boonmar S (2023) Seroprevalence of Orientia tsutsugamushi and Rickettsia typhi in water buffaloes (Bubalus bubalis) from Southern Thailand, Veterinary World, 16(8): 1600-1604.
Abstract

Background and Aim: Scrub typhus and murine typhus are globally distributed zoonoses caused by the intracellular Gram-negative bacteria Orientia tsutsugamushi and Rickettsia typhi, respectively. Numerous studies have been undertaken on rickettsial illnesses in humans and animals, including arthropod vectors, in Thailand. However, the reports on the seroprevalence of antibodies to O. tsutsugamushi and R. typhi in buffaloes is extremely rare. Thus, this study aimed to estimate the seroprevalence of both rickettsial infections in water buffaloes (Bubalus bubalis) in Phatthalung Province, southern Thailand.

Materials and Methods: From February to March 2023, a total of 156 serum samples were collected from 156 water buffaloes on 29 farms in Phatthalung province. The sera were screened for antibodies against O. tsutsugamushi and R. typhi using an indirect immunofluorescence assay.

Results: The seroprevalence of antibodies against O. tsutsugamushi and R. typhi in individual water buffaloes was 4.49% (95% confidence interval [CI]: 2.19%-8.97%) and 3.85% (95% CI: 1.77%-8.14%), respectively, whereas 31% (9/29) of the herds had buffaloes with antibodies. The number of buffaloes with scrub typhus infection and ectoparasite infestation was statistically significant (p < 0.05; odds ratio = 6.25 [95% CI: 1.19-33.33]). Intriguingly, the prevalence of scrub typhus antibodies in buffaloes that were not infested with ectoparasites was much higher than those that were.

Conclusion: This is the first report of O. tsutsugamushi and R. typhi antibodies in water buffalo sera in Southern Thailand. Two serum samples showed a high antibody titer against O. tsutsugamushi. Seroprevalence mainly occurred in non-ectoparasite-infested buffaloes, especially for O. tsutsugamushi antibodies. At the herd level, one-third of the studied farms showed seroprevalence. Additional research on the occurrence of these pathogens in vectors and in other animal reservoirs is necessary.

Keywords: indirect immunofluorescence assay, Orientia tsutsugamushi, Rickettsia typhi, seroprevalence, Thailand, water buffaloes.