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Wild rodents and their ectoparasites are known reservoirs for various zoonotic pathogens, highlighting the need for detailed studies into their roles in disease transmission. Our research investigated the spatial distribution of rodents and their ectoparasites to better understand the epidemiology of vector‐borne zoonotic diseases (VBZDs), including severe fever with thrombocytopenia syndrome (SFTS), Lyme disease, Q fever, and scrub typhus. We analyzed samples from 540 rodents and 6785 mites, detecting the presence of Borrelia spp., the causative agent of Lyme disease, in 0.9% of rodents and SFTS virus (SFTSV) in 1.0%. In mites, Borrelia spp. and Orientia tsutsugamushi, the bacteria causing scrub typhus, were detected in 0.3% of samples each. Phylogenetic analysis identified the SFTSV sequence as type B3, the Borrelia spp. sequence as B. afzelii, and the O. tsutsugamushi sequence as Karp‐related. Notably, SFTSV was detected for the first time in mites in South Korea, and B. afzelii was found in mites for the first time globally. These findings emphasize the critical need for continuous analysis of VBZDs to anticipate future trends and develop a comprehensive monitoring system. Further research into the rodent and mite populations in South Korea is essential to fully assess the potential risks of VBZDs. [ABSTRACT FROM AUTHOR]

Enterocytozoon bieneusi is an important microsporidian protozoa that causes intestinal disorders in humans. We collected 191 fecal samples from roadkill deer carcasses, among which 13 (6.8%) showed positive reaction for E. bieneusi by polymerase chain reaction assay. Phylogenetic analysis revealed 6 distinct genotypes, 1 of which was novel. All genotypes belonged to Group 1, which has low host specificity, indicating possible transmission through sylvatic cycle. E. bieneusi infection was predominant in female deer (P<0.05). [ABSTRACT FROM AUTHOR]

This study surveyed the current status of intestinal parasite infections in Korean dog fecal samples. A total of 367 fecal samples were collected from the northern (Seoul and Gyeonggi-do), central (Chungcheong-do), and southern (Gyeongsang-do) regions and analyzed using the saturated sodium nitrate flotation technique and the nucleotide sequences of 18S rRNA. Six species of intestinal parasites were detected using the flotation technique. Among them, helminth eggs detected included Toxocara canis (6.0%), Toxascaris leonina (1.1%), Trichuris vulpis (6.8%), Ancylostoma caninum (2.7%), and Spirometra sp. (1.1%). Additionally, Cystoisospora sp. (7.6%) oocysts were also detected. The prevalence of intestinal parasite infections was higher in shelter dogs than in pet dogs. Molecular genetic assays revealed the gdh and 18S rRNA genes of Giardia duodenalis (type D) in 4.9% of fecal samples. To the best of our knowledge, 18S rRNA genes of Cryptosporidium canis were identified in 1.9% of fecal samples for the first time in Korea. These findings provide an overview of the current status of intestinal parasite infections in fecal samples of dogs from Korea and can be helpful in the surveillance of zoonotic parasite infections related to dogs. [ABSTRACT FROM AUTHOR]

The gut microbiome is essential for the health of carnivorous mammals, including the endangered Siberian tiger (Panthera tigris altaica). However, limited research exists on the gut microbiome of captive Siberian tigers, especially regarding how diet and health status influence microbial diversity. This study addresses this gap by investigating the gut microbiome diversity and composition of six captive-born Siberian tigers housed at the Baekdudaegan National Arboretum in South Korea, using 16S rRNA gene sequencing. The study aimed to examine how diet and health status influence microbial communities, providing baseline data for managing captive tigers. Alpha diversity analysis revealed significant variation in microbial richness and evenness, with Tigers 2 and 6 exhibiting the highest microbial diversity and Tiger 3 the lowest, likely due to its surgical history and limited diet. Beta diversity analysis showed distinct microbial community structures influenced by diet and health. Taxonomic profiling identified Firmicutes and Bacteroidota as the dominant phyla, with Clostridium sensu stricto more prevalent in healthier tigers, while Escherichia-Shigella and Proteobacteria were abundant in tigers with lower diversity, suggesting dysbiosis. Comparisons with other tiger species confirm that diet, health, and captivity significantly shape the gut microbiome. These findings highlight the need for personalized health management in captive environments. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the diversity and prevalence of tick-borne protists in the Republic of Korea via DNA barcoding using 18S rRNA gene fragments and PCR. Between 2021 and 2022, questing ticks were collected using the flagging method, with a total of 13,375 ticks collected and pooled into 1003 samples. Of these, 50 tick pools were selected for DNA barcoding targeting the V4 and V9 regions of 18S rRNA using the MiSeq platform. A taxonomic analysis of the amplicon sequence variants identified three genera of protozoa, namely Hepatozoon canis, Theileria luwenshuni, and Gregarine sp. However, the number and abundance of protists detected were different depending on the primer sets, and T. gondii was not identified in DNA barcoding. Furthermore, conventional PCR confirmed the presence of H. canis, Toxoplasma gondii, T. luwenshuni, and Theileria sp. in the collected ticks. This study identified H. canis and T. gondii in Ixodes nipponensis for the first time. It demonstrated that the results of DNA barcoding using 18S rRNA gene fragments can vary depending on the primer sets and further optimization is required for library construction to identify tick-borne protists in ticks. Despite these limitations, the findings highlight the potential of DNA barcoding using 18S rRNA gene fragments for screening the diversity of tick-borne protists in ticks. [ABSTRACT FROM AUTHOR]

Simple Summary: Rodents are known to carry a variety of pathogens that can cause diseases in humans, especially those transmitted through small parasites like mites. This study investigated the presence of three specific bacteria, Anaplasma, Ehrlichia, and Rickettsia, in rodents and their mites across Korea in 2022 and 2023. We found that 10.3% of the 835 rodents were infected with Anaplasma phagocytophilum, 0.5% with Ehrlichia muris, 0.2% with Ehrlichia ruminantium, and 2.9% with Rickettsia raoultii. In addition, 8.8% of 7971 mites tested positive for Anaplasma, and lower percentages of the mites tested positive for the other bacteria. Importantly, this is the first time these bacteria have been detected in rodents and mites in Korea, and in some cases, globally. Our findings highlight the need for ongoing monitoring and better systems to track these diseases to prevent future outbreaks, especially as climate and environmental changes may increase their spread. This information is vital for public health awareness and protection from vector-borne diseases. Rodents are reservoirs for zoonotic pathogens, making it essential to study both rodents and their ectoparasites. In 2022 and 2023, we investigated the spatial distribution of rodents and their mites across Korea, focusing on three vector-borne diseases (VBDs): Anaplasma, Ehrlichia, and Rickettsia. A total of 835 wild rodents were collected from 16 locations, each consisting of five distinct environmental settings (mountains, waterways, reservoirs, fields, and paddy fields), with 20 traps per setting, totaling 100 Sherman live folding traps per site. Each rodent was identified using a taxonomic key, and post-mortem examinations led to the collection of 7971 mites (498 pools), followed by PCR analysis. Among the rodents, Anaplasma phagocytophilum was detected in 10.3%, Ehrlichia muris in 0.5%, Ehrlichia ruminantium in 0.2%, and Rickettsia raoultii in 2.9%. In mites, A. phagocytophilum was found in 8.8%, E. muris in 0.2%, R. raoultii in 0.2%, R. endosymbiont in 1.6%, and R. australis in 1.2%. This study marks the first detection of E. muris and R. raoultii in Korean rodents and the first global discovery of E. ruminantium in rodents. The detection of multiple pathogens in mites worldwide highlights the importance of continuous VBD monitoring to mitigate public health risks. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii, a common protozoan parasite, poses significant public health risks due to its potential to cause toxoplasmosis in humans and can be contracted from pigs, which are considered its critical intermediate host. The aim of this study is to evaluate the prevalence of T. gondii in slaughtered pigs for human consumption, emphasizing the zoonotic implications and the need for improved biosecurity and monitoring practices in pig farming. A total of 1,526 pig samples (1,051 whole blood samples and 384 lung tissue samples from the local slaughterhouse and 91 aborted fetus samples from local farms) were collected throughout the whole country of Korea in 2020. Among them, 6 (0.4%) were found to be infected with T. gondii by nested PCR. When compared by sample type, the prevalence of T. gondii was significantly higher in the aborted fetus samples (2.2%, 2/91) than in the blood (0.3%, 3/1,051) and lung tissue samples (0.3%, 1/384). The B1 gene sequence of T. gondii was similar (97.9–99.8%) to that of the other T. gondii isolates. This study represents the first molecular genotyping survey of T. gondii in the lung tissue of fattening pigs and aborted fetuses in Korea. Our findings indicated the importance of adopting preventive measures including the implementation of rigorous farm hygiene protocols and the promotion of public awareness about the risks of consuming undercooked pork. By addressing the gaps in current control strategies and encouraging the One Health approach, this study contributes to the development of more effective strategies to mitigate the transmission of T. gondii from pigs to humans, ultimately safeguarding public health. [ABSTRACT FROM AUTHOR]

Middle East respiratory syndrome coronavirus (MERS-CoV) causes fatal infections, with about 36% mortality in humans, and is endemic to the Middle East. MERS-CoV uses human dipeptidyl peptidase 4 (hDPP4) as a receptor for infection. Despite continued research efforts, no licensed vaccine is available for protection against this disease in humans. Therefore, this study sought to develop an inactivated fragmented MERS-CoV vaccine grown in Vero cells in an hDPP4-transgenic mouse model. Two-dose immunisation in mice with 15, 20, or 25 μg of spike proteins of inactivated split MERS-CoV antigens induced neutralising antibodies, with titres ranging from NT 80 to 1280. In addition, all immunised mice were completely protected, with no virus detection in tissues, weight loss, or mortality. The immunised splenocytes produced more cytokines that stimulate immune response (IFN-γ and TNF-α) than those that regulate it (IL-4 and IL-10). Taken together, the inactivated fragmented MERS-CoV vaccine is effective for the protection of mice against lethal MERS-CoV. Thus, the inactivated fragmented MERS-CoV vaccine warrants further testing in other hosts. [ABSTRACT FROM AUTHOR]

Ticks are responsible for mechanical damage to animal blood vessels and skin and are known to transmit a wide range of bacteria, viruses, and protozoa, causing severe infections in animals [...]

Q fever is a zoonotic disease caused by the extremely infectious bacterium Coxiella burnetii. Humans can be infected by inhalation of infectious aerosols or contaminated dust from infected ruminants or [...]