The Genus Haemaphysalis (Acari: Ixodidae) in Laos: An Update of Species Records and a Review of Taxonomic Challenges

Challenges for ticks and tick-borne diseases research in Southeast Asia: Insight from the first international symposium in Cambodia

BACKGROUND

Ticks, as critical vectors of a variety of pathogens, pose a significant public health challenge globally. In Southeast Asia (SEA), ticks are responsible for transmitting a diverse array of pathogens affecting humans and animals. The geographical and ecological diversity of SEA provides a unique environment that supports a wide range of tick species, which complicates the management and study of tick-borne diseases (TBDs).

METHODOLOGY/PRINCIPAL FINDINGS

This article synthesizes findings from the first international symposium on ticks and TBDs in Southeast Asia, held in Phnom Penh on June 22 and 23, 2023. It highlights regional efforts to understand tick ecology and pathogen transmission. This paper proposes to present a summary of the various presentations given during the symposium following 3 main parts. The first one is devoted to the state of knowledge regarding ticks and TBDs in SEA countries, with presentations from 6 different countries, namely Cambodia, Indonesia, Laos, Malaysia, Thailand, and Vietnam. The second part focuses on the development of new research approaches on tick-borne pathogens (TBPs) and TBDs. The last part is a summary of the round table discussion held on the final day, with the aim of defining the most important challenges and recommendations for researches on TBP and TBD in the SEA region.

CONCLUSIONS/SIGNIFICANCE

Key topics discussed include advancements in diagnostic tools, such as MALDI-TOF MS and proteomics, and the development of sustainable strategies for tick management and disease prevention. The symposium facilitated the exchange of knowledge and collaborative networks among experts from various disciplines, promoting a unified approach to tackling TBDs in the region. The symposium underscored the need for enhanced surveillance, diagnostics, and inter-regional cooperation to manage the threat of TBDs effectively. Recommendations include the establishment of a regional database for tick identification and the expansion of vector competence studies. These initiatives are crucial for developing targeted interventions and understanding the broader implications of climate change and urbanization on the prevalence of TBDs.

Ectoparasites Infestation to Small Ruminants and Practical Attitudes among Farmers toward Acaricides Treatment in Central Region of Java, Indonesia

Ectoparasite infestations are one of the major problems affecting goat and sheep farming. Disease resulting from these infestations can cause changes in physical appearance, such as severe lesions on the skin, and economic consequences in the form of significantly reduced selling prices. This study aimed to determine the prevalence of ectoparasites in the Boyolali district, Central Java, Indonesia. A total of 651 sheep and goats were surveyed in this study. The parasites were collected via skin scraping, twister, or manually from clinically infected goats and sheep in traditional farms. All of the ectoparasites collected were successfully identified. The prevalence of ectoparasites in ruminants in Boyolali was 97.8% (637/651). The species make-up was as follows: Bovicola caprae 97.8% (637/651), Linognathus africanus 39% (254/651), Haemaphysalis bispinosa 3.5% (23/651), Ctenocephalides spp. 0.2% (1/651), and Sarcoptes scabiei 5.2% (34/651). The predilection sites were in the face, ear, and leg areas, and in the axillary, dorsal, abdomen, and scrotum regions of the surveyed animals. An evaluation of farmers' attitudes to ectoparasites was performed using a questionnaire. The findings of this study imply that animals in the investigated area are highly exposed to ectoparasite infestations. Given the importance of ectoparasites in both livestock and human communities, specifically in the health domain, more research into appropriate control strategies is necessary.

First Autochthonous Report on Cattle Babesia naoakii in Central Java, Indonesia, and Identification of Haemaphysalis bispinosa Ticks in the Investigated Area

In tropical countries, clinical bovine babesiosis is a tick-borne disease primarily caused by Babesia bovis and Babesia bigemina. Here, we investigated 11 cattle with presumptive diagnosis of clinical babesiosis in Boyolali district, Central Java, Indonesia. The majority of the animals were anemic, as evidenced by lower hematocrit, hemoglobin concentration, and red blood cell counts than the normal ranges. Blood DNA was analyzed by a PCR assay targeting the 18S rRNA-ITS region of babesial origin, and the results confirmed that the cattle were infected with Babesia species. The sequencing and phylogenetic analyses demonstrated that the animals were infected with Babesia naoakii. This is the first report of B. naoakii in Indonesia and of B. naoakii-induced clinical bovine babesiosis outside of Sri Lanka. B. naoakii causes a persistent infection, as indicated by positive PCR results for serial blood samples of the circulatory system taken two weeks after treatment. Consequently, subclinical or newly recovered cattle may serve as potential intermediate hosts and infect ticks as definitive hosts to complete the life cycle. To identify potential tick vectors, we collected ticks from cattle, including 11 animals with clinical babesiosis. Based on the morphology and the mitochondrial cytochrome c oxidase subunit 1 (COX1) of collected ticks, we found that all of the collected ticks were Haemaphysalis bispinosa, identifying this tick species as a potential vector of B. naoakii in Indonesia. In this study, the evaluation of local farmers' awareness and practices regarding tick-borne diseases is presented, as disease prevention is also reliant on the implementation of strategies for vector control. Since livestock activities in Java represent the country's busiest animal trade, thereby the spread of disease to other regions is possible through anthropogenic factors. In conclusion, B. naoakii is a causative pathogen of clinical bovine babesiosis autochthonously occurred in this report and further research on B. naoakii-infection is required in other regions of the country. The prompt treatment of the disease seemed crucial for animal survival, which implies the necessity of early diagnosis and a sensitive detection method.