• Korean Journal of Clinical Laboratory Science
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• v.47 no.3
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• pp.147-152
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• 2015

The seasonal pattern of larvae, nymph and adult life stages for three tick species were studied for April-October, 2014. Haemaphysalis longicornis (610), Haemaphysalis flava (296) and Ixodes nipponensis (15) were collected from Pocheon by the dragging and flagging method. H.longicornis (254), H.flava (345) and I.nipponensis (15) were collected from Cheolwon in the same way. H.longicornis adults peaked in June while nymphs were more frequently collected from April through June. In contrast, H.longicornis larvae were collected only in September and October. H.flava adults were collected in April, September, and October while nymphs were collected from April through October. The nymphs peaked in April in Pocheon while May was the peak in Cheolwon. Larvae of H.longicornis and H.flava were collected only in September and October. I.nipponensis adults and nymphs were more frequently collected in April, while the larvae were not collected during that period. Collecting ticks by the dragging and flagging method provides estimates of population densities for life stages of the selected species and the associated disease risk. These results can be used to predict seasonal population densities of ticks and the prevalence of tick-borne pathogens.

• Korean journal of applied entomology
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• v.60 no.3
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• pp.323-329
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• 2021

This study investigated the seasonal distribution of ticks in Boeun, Chungbuk, South Korea, from 2016 to 2020. Over the five-year period, ticks were collected annually from four different sites. A total of 17,704 ticks belonging to three tick species (Haemaphysalis longicornis, Haemaphysalis flava, and Ixodes nipponensis) were collected. H. longicornis was the dominant species across all four sites with the highest density of 68.40% of the total collected specimens, followed by H. flava (3.53%) and I. nipponensis (0.06%). The larvae of unidentified species were also collected: 11.81 T.I. (28.01%). The H. longicornis population peaked during the spring season (May-June), whereas the larval population peaked during August and September. H. longicornis was collected the most from four sites (coniferous forest, broad-leaf forest, mountain path, and copse), with the exception of the larvae, which was collected the most in grassland and grave. H. flava was collected from all sites, but in a small proportion. The SFTS virus was not found in any of the 828 pools of ticks during 2016-2020. Based on the results of this study, the continuous surveillance of the tick population is recommended to mitigate the spread of diseases by these vectors.

• Korean journal of applied entomology
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• v.60 no.3
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• pp.315-322
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• 2021

This study investigated the acaricidal and repellent activities of various plant extracts and Cnidium officinale-derived materials against Haemaphysalis longicornis. Among the 24 methanolic plant extracts, C. officinale showed the highest acaricidal activity (93.3%) against H. longicornis. Platycodon grandiflorus, Phytolacca americana, Magnolia denudata, Houttuynia cordata, C. officinale, and Pueraria montana showed significant differences in their repellent activity. Consequently, the activity of solvent-fractionated materials and the derived material of the C. officinale, was investigated and a 90% acaricidal effect was observed three days after hexane fraction treatment, indicating that the repellent response was statistically significant. Butylidenephthalide, which is a C. officinale-derived compound, showed 90% acaricidal activity seven days after treatment. Additionally, all H. longicornis moved to the untreated area in the t-tube olfactometer experiment, confirming the repellent activity of butylidenephthalide. Therefore, the results of this study suggest the use of C. officinale crude extract and butylidenephthalide as potent acaricidals and repellents against H. longicornis, respectively.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.2
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• pp.143-149
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• 2020

The study examined the seasonal pattern of larvae, nymph, and adult life stages for Haemaphysalis longicornis and the rate of infection with severe fever from the thrombocytopenia syndrome virus in ticks collected from 12 sections (Jichukdong), 14 sections (Uldaeri), and 18 sections (Howondong) in Bukhansan dullegil for April-October 2019. Haemaphysalis longicornis ticks have been considered the main vector for severe fever with thrombocytopenia syndrome (SFTS). Haemaphysalis flava and Ixodes nipponensis were collected using the dragging and flagging method. The ratios of Haemaphysalis longicornis of the collected ticks were 91% (Jichukdong), 94% (Uldaeri), and 98% (Howondong). Monthly distributional studies of Haemaphysalis longicornis based on the developmental stage showed that the adults peaked in September while nymphs were collected more frequently from April through June. The larvae peaked in September and October. SFTS virus detection was performed using 2 × OneStep RT-PCR and nested PCR. On the other hand, no SFTS virus-specific gene was detected in 1,158 ticks of Haemaphysalis longicornis. This result provides estimates of the population densities for the life stages of Haemaphysalis longicornis and the associated disease risk in Bukhansan dullegil, where many people have visited since opening in 2010.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.423-428
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• 2018

Anaerobic growth-inhibiting and acaricidal activities of 2'-hydroxy-5'-methoxyacetophenone derived from Cyanachum paniculatum oil and its derivatives against five intestinal bacteria (Bifidobacterium bifidum, B. longum, Clostridium pefringens, Escherichia coli and Lactobacillus casei) and Haemaphysalis longicornis were examined. In the packet test against the larvae of H. longicornis, none of the C. paniculatum oil exhibited acaricidal activity, while the C. paniculatum oil showed only antimicrobial activity against five intestinal bacteria in the disc diffusion method. Based on the inhibition zones and MIC values, 2',4'-dimethoxyacetophenone, 2',5'-dimethoxyacetophenone, 2'-hydroxy-4'-methoxyacetophenone, 2'-hydroxy-5'-methoxyacetophenone, 2'-methoxyacetophenone, and 4'-methoxyacetophenone, containing a methyl group on the acetophenone skeleton, possessed growthinhibiting activities against C. perfringens and E. coli. However, acetophenone, 2'-hydroxyacetophenone, 4'-hydroxyacetophenone, 2',4'-hydroxyacetophenone and 2',5'-hydroxyacetophenone, which contained a hydroxyl group on the acetophenone skeleton, had no growth-inhibiting activity against intestinal bacteria. These results indicated that 2'-hydroxy-5'-methoxyacetophenone and its derivatives could potentially be developed as natural antimicrobial agents to specific control of C. perfringens and E. coli.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.233-241
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• 2020

Several hard tick species in Ixodidae are medically important pests that transmit infectious disease including severe fever with thrombocytopenia syndrome (SFTS). In Korea, the number of SFTS patients continues to steadily increase since its first report in 2013, and Gyeongsangbuk-do (province) is the second most frequent area of SFTS patient occurrence. In order to investigate the distribution of ticks in Sangju city, we collected ticks using the flagging method from 26 sites comprising urban green area, vulnerable area of management, and rural area, and examined SFTS virus from the collected ticks in 2019. Based on Collection Index (CI = tick number / 1 h / 2 people), CI 143 ticks, including Haemaphysalis longicornis, Haemaphysalis flava, and Ixodes nipponensis, were collected; the most abundant species among the three tick species was H. longicornis (CI 138, 96.5%). Ninety two percent (CI 131) of ticks were collected in vulnerable area of management, where people cannot easily enter and are not managed by city hall, whereas only 8.4% (CI 12) were collected in the urban green area and rural area. Regarding SFTS virus detection, virus was not investigated from 26 pools containing CI 143 ticks. The results of this study are expected to be used as a recommendation for ensuring the safety of local residents from tick-borne diseases.

• Journal of Applied Biological Chemistry
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• v.62 no.1
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• pp.19-23
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• 2019

The chemical compositions of the essential oil of Valeriana officinalis roots obtained by steam distillation method were analyzed by GC-MS. The 16 constituents were identified in the V. officinalis oil, and the most abundant compounds were patchouli alcohol (18.69%) and ${\beta}$-gurjunene (15.26%). Acaricidal effects of the V. officinalis oil were evaluated against Tyrophagus putrescentiae, Haemaphysalis longicornis larva and H. longicornis nymph by contact bioassay. The $LD_{50}$ values against T. putrescentiae, H. longicornis larva and H. longicornis nymph were 28.01, 178.26 and $207.98{\mu}g/cm^2$, respectively. Agar disc diffusion bioassay showed the antibacterial activity of the V. officinalis oil against foodborne pathogens, especially L. monocytogenes. These results showed that the essential oil of V. officinalis roots derived from USA has a potential for development as acaricide and antimicrobial.

• Korean journal of applied entomology
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• v.62 no.2
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• pp.95-102
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• 2023

The number of households with pets has increased in recent years. Consequently, interest in mites and their odors has increased. In this study, we investigated whether pyrethrum extract and water-soluble phytoncides are effective tick repellents, deodorizing agents, and antibacterial agents. In the tick-climbing test, the pyrethrum extract (23.33 points) and water-soluble phytoncide (22.00 points) showed a high repelling effect. To confirm the tick avoidance effect of the composite extract, a tick climbing test was conducted with a pest control extract, a composite extract (referred to as a sample) containing a water-soluble phytoncide, and a third-party product (control). The sample showed a high avoidance effect (13.00 points and Control 26.67 points. An indoor repellent efficacy test for ticks confirmed that the sample showed an excellent tick-repellent effect (88%) compared to the control (12%). As a result of a deodorization test, ammonia was shown to have a deodorizing effect of 98.3% and trimethylamine of 99.5%, whereas, in the antibacterial test, the E. coli, Staphylococcus aureus, and pneumonia groups showed an antibacterial effect of 99.9%. Combining the results of this study, it is judged that the complex extract including the above material has high utility value as a material that is effective in mite repellents, deodorization, and antibacterial activity.