Individual and Herd-Level Seroprevalence in Association with Potential Risk Factors of Japanese Encephalitis in Pigs Collected from Urban, Periurban, and Rural Areas of Bali, Indonesia

I Made Kardena; Anak Agung Ayu Mirah Adi; I Nyoman Mantik Astawa; Mark O'Dea; Ian Robertson; Shafi Sahibzada; Mieghan Bruce

doi:10.1155/2023/9682657

Individual and Herd-Level Seroprevalence in Association with Potential Risk Factors of Japanese Encephalitis in Pigs Collected from Urban, Periurban, and Rural Areas of Bali, Indonesia

Vet Med Int. 2023 Feb 15:2023:9682657. doi: 10.1155/2023/9682657. eCollection 2023.

Authors

I Made Kardena^{1

2}, Anak Agung Ayu Mirah Adi¹, I Nyoman Mantik Astawa¹, Mark O'Dea³, Ian Robertson², Shafi Sahibzada², Mieghan Bruce²

Affiliations

¹ Department of Pathobiology, Faculty of Veterinary Medicine, Udayana University, Jalan PB Sudirman, Denpasar 80234, Bali, Indonesia.
² School of Veterinary Medicine and Centre for Biosecurity and One Health, Harry Butler Institute, Murdoch University, Perth, 6150, Western Australia, Australia.
³ Department of Primary Industries and Regional Development (DPIRD), Diagnostics and Laboratory Services, Sustainability and Biosecurity, South Perth 6150, Western Australia, Australia.

Abstract

A study to assess the seroprevalence antibodies against JEV in pigs in Denpasar, Badung, and Karangasem as the representatives of urban, periurban, and rural areas in the province of Bali was conducted. Sampled pigs' blood was collected and their sera were tested for antibody detection using commercial IgG ELISA. A standard questionnaire was used to interview the pig owners or farmers to identify the determinants associated with the seropositivity of the antibodies. Overall, 96.6% (95% CI: 94.5-98.1) of 443 pig sera in individual animal-level seroprevalence were seropositive to the ELISA. Karangasem had the highest test prevalence at 97.3% (95% CI: 93.1-99.2) while Badung had a slightly lower prevalence at 96.6% (95% CI: 92.2-98.9), and Denpasar had the lowest prevalence at 96% (95% CI: 91.5-98.5) (p=0.84). In herd-level seroprevalence, all sampled herds contained one or more seropositive pigs (overall herd-level seroprevalence 100% [95% CI: 97.7-100]). No animal-level factors were significantly associated with seropositivity (all p values >0.05). For the herd-level risk factors relating to pig management and husbandry practices adopted, no analysis model could be generated, as all the sampled herds were seropositive. More than 90% seroprevalence detected in this study indicates high natural JEV infection occurred in pigs, which highlights the high public health risk of the infection in the areas.