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We developed a new concentration kit, called the ParaEgg (PE), for easy detection trematode eggs from fecal samples in endemic areas of clonorchiasis and metagonimiasis in Korea. To create a standard of detection efficiency, 120 fecal samples were examined using the water–ether concentration method (WECM). The PE kit and Mini ParaSep (PS) kit were used to compare the detection sensitivity of 100 egg-positive and 20 egg-negative samples in WECM. Additionally, stool samples, which were intentionally spiked with 10, 20, and 30 Clonorchis sinensis eggs, were evaluated to assess the sensitivity in low-infection cases. The PE and PS kits showed detection rates of 100% and 92%, respectively, from 100 egg-positive samples in WECM. Meanwhile, eggs were detected in 3 (PE) and 2 (PS) out of 20 egg-negative samples in WECM. The PE kit detected the highest number of eggs per gram of feces (727 on average), followed by the WECM (524) and PS kit (432). In fecal samples that were intentionally spiked with 10, 20, and 30 C. sinensis eggs, PE only detected eggs 2 out of 5 samples in 10 eggs spiked (40%), and the detection rates were 80% and 100%, respectively. The PE kit enabled a more accurate identification of trematode eggs because of the clearance of small fecal debris in the microscopic field. In conclusion, the PE kit is obviously helpful to detect and identify trematode eggs in stool examinations especially in endemic areas of clonorchiasis and metagonimiasis. [ABSTRACT FROM AUTHOR]

Simple Summary: Many tick species pose a threat to public health by transmitting diseases to humans and animals. Haemaphysalis longicornis (The Asian longhorned tick) is known to be the main vector that transmits severe fever with thrombocytopenia syndrome virus. In the United States, it was first identified in New Jersey during 2017 on domestic sheep. Even though H. longicornis is an important vector, research on its major activity period is lacking. Tick activity patterns may vary depending on climate factors, the host, and region. This study aimed to survey the patterns of diel activity in H. longicornis and the potential effects of climatic factors on tick activity. The highest activity occurred at 10:00 to 14:00. Avoiding the times of highest activity is considered the best way to reduce contact with ticks. Haemaphysalis longicornis is one of the most medically important carriers of various pathogens. Although H. longicornis is an important vector, only basic ecological and biological information has been obtained, primarily focusing on its abundance and distribution. This study determined the most active time and meteorological conditions for the diel activity of H. longicornis. The diel activity pattern of H. longicornis was the highest between 10:00 and 14:00, and the lowest between 22:00 and 02:00. The major activity temperature of H. longicornis was between 25 °C and 40 °C, with the highest activity at 35 °C. The relative humidity was between 30% and 70% during the active period. Temperature had the highest correlation with diel activity (R = 0.679), followed by humidity (R = −0.649) and light intensity (R = 0.572). Our results provide basic information for the development of tick-borne disease vector control programs and tick surveillance. [ABSTRACT FROM AUTHOR]

The Rickettsia species transmitted by ticks are mostly classified within the spotted fever group rickettsiae (SFGR), which causes tick-borne rickettsiosis. Although efforts have been made to investigate their prevalence in the Republic of Korea (ROK), research has been limited to certain areas. Furthermore, the pooling method for ticks does not fully reflect the exact infection rate. Therefore, we aimed to perform molecular identification of SFGR in ticks to elucidate the current prevalence of tick-borne rickettsiosis in the ROK. The SFGR of ticks was identified using polymerase chain reaction targeting the 17 kDa antigen, ompA, and gltA, followed by sequencing for species identification and phylogenetic analysis. In total, 302 ticks belonging to four species (Haemaphysalis flava, H. longicornis, Ixodes nipponensis, and Amblyomma testudinarium) were collected between April and November 2022. The overall SFGR infection rate was 26.8% (81/302 patients). Both adult and nymphal ticks and the SFGR infection rate increased during April–May, reaching their peaks in June, followed by a marked decline in August and July, respectively. Phylogenetic analysis revealed three species (R. monacensis, R. heilongjiangensis, and Candidatus R. jingxinensis) of SFGR. Thus, our results emphasize the importance of tick surveys for the prevention and management of tick-borne rickettsiosis. [ABSTRACT FROM AUTHOR]

Simple Summary: Mosquito collection traps are an essential tool for monitoring mosquito density and species distribution. Various traps are used in mosquito surveillance projects in the Republic of Korea. However, there is a lack of comparative analysis of these traps. Therefore, we evaluated four traps that are widely used for mosquito surveillance. BLT showed superior collection efficiency in terms of the number of collected individuals and species evenness, whereas BGT showed the highest species diversity among all the traps. DMS is well adapted to urban areas and has an advanced function that can automatically count the number of mosquitoes. In our summary, we provide information about the traps and guidance for planning new mosquito surveillance projects. Monitoring mosquito populations is essential for controlling mosquito-borne diseases, and the selection of mosquito traps should be tailored to specific surveillance objectives. Here, we tested four mosquito traps for their efficiency and applicability: the Nozawa-style black light trap (BLT), BG-sentinel trap II (BGT), UV-LED Blackhole Plus Mosquito Buster trap (LED), and digital mosquito monitoring system (DMS). The traps were rotated weekly for a 24 h cycle at the same location for 13 weeks. Overall, 1649 female mosquitoes belonging to seven genera and sixteen species were collected by the traps. The traps exhibited differences in both the number of collected individuals and species composition. The BLT showed superior collection efficiency in terms of the number of collected individuals and species evenness, whereas the BGT showed the highest species diversity among all the traps. Thus, the BLT and BGT are the best choices for effective mosquito surveillance based on trap performance. Additionally, despite the relatively low efficiency of the LED and DMS observed in this study, the LED is known to be efficient when used for indoor conditions such as cowsheds, while the DMS has an advanced function that can automatically count the number of mosquitoes. Thus, our findings provide significant guidelines for planning new mosquito surveillance projects in the ROK. [ABSTRACT FROM AUTHOR]

Human babesiosis is an emerging tick‐borne zoonotic disease prevalent in large parts of the world. This study aimed to examine the status of Babesia microti infection in ticks collected from small mammals captured during the nationwide survey of the Republic of Korea (ROK), 2017. Ixodid ticks from small mammals of three species, Apodemus agrarius, Crocidura lasiura, and Tscherskia triton, were used for the molecular detection of B. microti. PCR analyses amplifying 18S ribosomal RNA (rRNA) of the genus Babesia showed 8.4% of the ticks to be positive. Nucleotide sequencing of the PCR products revealed two different genotypes of B. microti, the US and Kobe‐type. The US‐types of B. microti were detected in ticks from small mammals of almost all study sites, whereas detections of Kobe‐types were restricted to ticks from southern part of ROK. Phylogenetic analysis also indicated that each of the two types of B. microti clustered into two distinct clades. This is the first report on the presence of the US and Kobe‐type B. microti in ticks collected from small mammals trapped on a national scale in ROK. [ABSTRACT FROM AUTHOR]

Ticks are important vectors of the tick-borne encephalitis virus (TBEV). In Kyrgyzstan, the livestock farming trade and nomadic lifestyle enable tick-borne diseases to be imported from neighboring countries, but there are few relevant studies. In this study, we collected 40 ticks from cattle in Kyrgyzstan. Molecular marker analysis identified the ticks as Ixodes persulcatus (97.5%; n = 39) and Haemaphysalis punctata (2.5%; n = 1). Real-time PCR screening revealed two ticks to be positive for TBEV, but only one tick was amplified using nested PCR targeting the TBEV envelope (E) and non-structure 5 (NS5) gene. The obtained sequences belonged to the TBEV Siberian subtype and phylogenetic tree analysis results confirmed that the virus was related to the Bosnia strain. We also performed next-generation sequencing, which confirmed the TBEV Siberian subtype. Continuous research and surveillance of TBEV in Kyrgyzstan are required to provide further information on tick-borne diseases. [ABSTRACT FROM AUTHOR]

Ticks are vectors that cause disease by transmitting bacteria, viruses, and protozoa to humans or animals. The Asian longhorned tick Haemaphysalis longicornis, a vector of medical and veterinary importance, is widely distributed in the Korean peninsula and can transmit various pathogens including Rickettsia spp., Borrelia spp., Francisella spp., Coxiella spp., and severe fever with thrombocytopenia syndrome virus (SFTS virus). Despite the abundance and importance, studies on the microbiome of H. longicornis in Korea are limiting. Here we first report the microbiome diversity of H. longicornis in terms of region, stage, and sex. H. longicornis used in this study were collected from 16 different regions. The V3‐V4 region was amplified and sequenced by MiSeq platform. The microbial diversity analysis was performed using Qiime2. A total of 1,754,418 non‐chimeric reads were obtained from a total of 46 samples, and an average of 126 operational taxonomic units (OTUs) and a total of 1,398 OTUs were identified. Our results were used for H. longicornis microbial community database construction for each region that enables to identify singularities in each region. [ABSTRACT FROM AUTHOR]

Mosquitoes have adapted to various environmental conditions. Symbionts with mosquitoes impact this adaptation in different environments. In the field, mosquitoes could get exposed to antibiotics during their developmental period, which could reduce or eliminate their symbiotic microbes. However, the side effects of the antibiotics on the ovary and reproductive physiology of the Asian tiger mosquito, Aedes albopictus remains unknown. In this study, we investigated the effects of tetracycline and combinations of rifampicin and tetracycline at environmentally acceptable levels on the reproductive physiology of ovaries in Ae. albopictus. Rifampicin and tetracycline in combination reduced the hatching rate and fertility of Ae. albopictus compared to the untreated control group. These antibiotics induced histopathological damage and reactive oxygen species production in the ovaries. The combination of antibiotics decreased the expression of surface protein of Wolbachia (WSP) in Ae. albopictus. Additionally, the expression of Toll like receptor 2 (TLR2) and Myd88 were triggered by the combinations. The findings demonstrate the detrimental effects of antibiotics, particularly combinations of rifampicin and tetracycline, on the reproductive capacity of Ae. albopictus females. [ABSTRACT FROM AUTHOR]

The Asian longhorned tick, Haemaphysalis longicornis, is widely distributed in China, Japan, and Korea and may transmit infectious diseases. Severe fever with thrombocytopenia syndrome (SFTS) is an important tick‐borne disease caused by the SFTS virus (SFTSV). Deep sequencing to confirm the presence of SFTSV in ticks has not been reported in Korea. To detect SFTSV, RNA was extracted from tick samples and analyzed using high‐throughput deep sequencing. Based on BLASTN results, numerous SFTSV reads were identified. Moreover, a nearly complete genome of SFTSV (JNU‐1 isolate) was obtained using Sanger sequencing. The genome of the JNU‐1 isolate includes three segments of 6,286, 3,299 and 1,642 nucleotides (nt) termed large (L), medium (M), and small (S), respectively. Also, phylogenetic and recombination analyses for each segment of SFTSV were performed using the JNU‐1 isolate. The three segments of JNU‐1 isolate were closely related to the genotype B known human‐derived Korean SFTSV isolate; the JNU‐1 isolate showed no recombination sites with other isolates. This study is the first report of detection of SFTSV from ticks using deep sequencing in Korea and provides information on the genetic diversity of SFTSV in East Asia. [ABSTRACT FROM AUTHOR]