The seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus was monitored with a collection trap method every April to November during 2015–2018 and with a flagging method every July and August during 2015–2018 in Ganghwa-do (island) of Incheon Metropolitan City, Republic of Korea. This monitoring was performed in a copse, a short grass field, coniferous forest and broad-leaved forest. A total of 17,457 ticks (8,277 larvae, 4,137 nymphs, 3,389 females, and 1,654 males) of the ixodid ticks comprising 3 species (Haemaphysalis longicornis, H. flava, and Ixodes nipponensis) were collected with collection traps. Of the identified ticks, H. longicornis was the most frequently collected ticks (except larval ticks) (94.26%, 8,653/9,180 ticks (nymphs and adults)), followed by H. flava (5.71%, 524/9,180) and Ix. nipponensis (less than 0.04%, 3/9,180). The ticks collected with collecting traps were pooled and assayed for the presence of SFTS virus with negative results. In addition, for monitoring the prevalence of hard ticks, a total of 7,461 ticks (5,529 larvae, 1,272 nymphs, 469 females, and 191 males) of the ixodid ticks comprising 3 species (H. longicornis, H. flava, and Ix. nipponensis) were collected with flagging method. H. longicornis was the highest collected ticks (except larval ticks) (99.53%, 1,908/1,917 ticks (nymphs and adults)), followed by H. flava (1.15%, 22/1,917).
Climate Change ; Coniferophyta ; Female ; Fever ; Forests ; Humans ; Incheon ; Ixodes ; Ixodidae ; Larva ; Methods ; Nymph ; Poaceae ; Prevalence ; Republic of Korea ; Seasons ; Thrombocytopenia ; Ticks

Tick saliva is critically important for continuous attachment to the host, blood feeding for days, and transmission of tick-borne pathogens. To characterize the patterns of inflammatory cytokine gene expression during its attachment and blood sucking time, peripheral blood samples of rabbits infested with Haemaphysalis longicornis ticks were collected at different intervals. Blood histamine concentration was evaluated as well as gene encoding IFN-γ, TNF-α, IL-2, IL-6, IL-4, and IL-10 were compared with non-infested rabbits. Blood histamine concentration of tick-infested rabbits during fast feeding time was significantly higher than that of non-infested rabbits. In both nymph and adult tick infested rabbits, expression of TNF-α and IFN-γ genes were decreased significantly (P < 0.05), while expression of IL-4, IL-6, and IL-10 were increased 1.3 to 7 folds in adult infested rabbits with the exception of IL-6 that was significantly (P < 0.05) decreased in nymph infested rabbits. IL-2 was not expressed in either nymph or adult infestation. H. longicornis saliva is capable of modulate host responses through a complex correlation with histamine and Th1, Th2 mediated cytokines that suppress the inflammatory responses directed toward inflammatory mediators introduced into the host during tick feeding.
Adult ; Cytokines ; Gene Expression ; Histamine ; Humans ; Interleukin-10 ; Interleukin-2 ; Interleukin-4 ; Interleukin-6 ; Nymph ; Rabbits ; Saliva ; Ticks

This article reviews Leptotrombidium deliense, including its discovery and nomenclature, morphological features and identification, life cycle, ecology, relationship with diseases, chromosomes and artificial cultivation. The first record of L. deliense was early in 1922 by Walch. Under the genus Leptotrombidium, there are many sibling species similar to L. deliense, which makes it difficult to differentiate L. deliense from another sibling chigger mites, for example, L. rubellum. The life cycle of the mite (L. deliense) includes 7 stages: egg, deutovum (or prelarva), larva, nymphochrysalis, nymph, imagochrysalis and adult. The mite has a wide geographical distribution with low host specificity, and it often appears in different regions and habitats and on many species of hosts. As a vector species of chigger mite, L. deliense is of great importance in transmitting scrub typhus (tsutsugamushi disease) in many parts of the world, especially in tropical regions of Southeast Asia. The seasonal fluctuation of the mite population varies in different geographical regions. The mite has been successfully cultured in the laboratory, facilitating research on its chromosomes, biochemistry and molecular biology.
Adult ; Asia, Southeastern ; Biochemistry ; Ecology ; Ecosystem ; Host Specificity ; Humans ; Larva ; Life Cycle Stages ; Mites ; Molecular Biology ; Nymph ; Ovum ; Scrub Typhus ; Seasons ; Siblings ; Trombiculidae

Dual biocontrol of both insects and plant pathogens has been reported for certain fungal entomopathogens, including Beauveria bassiana and Lecanicillum spp. In this study, we demonstrate, for the first time, the dual biocontrol potential of two fungal isolates identified by morphological and phylogenetic analyses as Isaria javanica. Both these isolates caused mortality in the greater wax moth, and hence can be considered entomopathogens. Spores of the isolates were also pathogenic to nymphs of the green peach aphid (Myzus persicae), with an LC₅₀ value of 10⁷ spores/mL 4 days after inoculation and an LT₅₀ of 4.2 days with a dose of 10⁸ spores/mL. In vitro antifungal assays also demonstrated a strong inhibitory effect on the growth of two fungi that are pathogenic to peppers, Colletotrichum gloeosporioides and Phytophthora capsici. These results indicate that I. javanica isolates could be used as novel biocontrol agents for the simultaneous control of aphids and fungal diseases, such as anthracnose and Phytophthora blight, in an integrated pest management framework for red pepper.
Aphids* ; Beauveria ; Capsicum ; Colletotrichum ; Fungi* ; Hemiptera ; In Vitro Techniques ; Insects ; Mortality ; Moths ; Nymph ; Pest Control ; Phytophthora ; Plants* ; Prunus persica ; Spores

This study was performed to investigate the distribution of ticks and the rate of infection with severe fever with thrombocytopenia syndrome (SFTS) virus in ticks collected at Mt. Gwanak and the Seoul National University campus, Korea. Ticks (n = 273) were collected from May to October and included 76 Haemaphysalis longicornis (4 adult females, 72 nymphs), 49 Haemaphysalis flava (9 adult females, 3 adult males, 37 nymphs), and 148 Haemaphysalis spp. larvae. SFTS virus detection was performed by using one-step RT PCR and nested PCR. The SFTS virus was detected in 7 samples (1 Haemaphysalis longicornis nymph, 3 Haemaphysalis flava nymphs, and 3 Haemaphysalis spp. larva). The overall minimum field infection rate was 2.6%, whereas the minimum field infection rates of adult, nymphal, and larval ticks were 0%, 3.2%, and 2.0%, respectively. For a more accurate indication of the prevalence of SFTS virus in Korea, further in-depth investigations of tick species and SFTS virus occurrence over a larger area and longer period are needed.
Adult ; Female ; Fever* ; Humans ; Korea* ; Larva ; Male ; Nymph ; Polymerase Chain Reaction ; Prevalence* ; Seoul ; Thrombocytopenia* ; Ticks*

This study investigated the development characteristics of Dermacentor everestianus under laboratory conditions. The time taken for D. everestianus to complete the whole life cycle was 110.2 days on average, and the average developmental durations of larvae and nymphs were 17.1 days and 29.5 days, respectively. The summation of the prefeeding, feeding, and preoviposition periods of females was 17.8 days, and the oviposition and egg incubation lasted for 18.1 days and 27.7 days, respectively. A highly positive correlation was observed between the weight of engorged female and the number of egg mass laid (r=0.947). The reproductive efficiency index and the reproductive fitness index were 7.1 and 6.1, respectively.
Dermacentor* ; Female ; Genetic Fitness ; Humans ; Larva ; Life Cycle Stages* ; Nymph ; Oviposition ; Ovum

Ticks are parasites that usually suck the blood of wild or domestic animals; rarely, they ingest human blood and spread various febrile infectious diseases along with skin problems. Out of 40 cases of tick bite reported in Korea, only 3 were caused by nymphal ticks, and tick bites by nymphal Amblyomma testudinarium have not been reported previously. Herein, we report a rare case of tick bite by nymphal A. testudinarium. A 57-year-old woman presented with an asymptomatic solitary erythematous nodule on the left thigh that had been present for 6 days. The tick, which the patient removed from the lesion and brought to the hospital, was identified as a nymphal A. testudinarium. Doxycycline (200 mg) was used as treatment, and after seven days of use, the patient improved and no other lesions were detected.
Animals, Domestic ; Communicable Diseases ; Doxycycline ; Female ; Humans ; Korea ; Middle Aged ; Nymph ; Parasites ; Skin ; Thigh ; Tick Bites* ; Ticks*

Severe fever with thrombocytopenia syndrome (SFTS) is firstly reported in China in 2011. Thereafter it is reported an infectious disease in Japan and Korea. It is caused by bunyavirus, called SFTS virus (SFTSV). The main vector of SFTS is Haemaphysalis longicornis tick. We investigated the distribution and detection of SFTSV in ticks collected from the environment using the dragging method and dry ice fogging method from May to November 2014 in Jeollanam-do, Korea. Sampling was taken from the province Suncheon, Gokseong, Boseong, Goheung where patients have occurred in 2013 and Gurye as control. Among the total 3,048 ticks collected, 3,030 ticks were H. longicornis (99.4%) and 18 were Amblyomma testudinarium. H. longicornis was collected 1,330 ticks in Gokseong, 1,188 ticks in Boseong, 240 ticks in Suncheon, 150 ticks in Goheung and 140 ticks in Gurye. Developmental stages by month of H. longicornis were revealed that nymph (92%) was collected from May to June, adult (30%) and nymph (70%) in July, and 93% of larvae from September to October. These results showed the different dominant stage of ticks according to seasons. However, no SFTSV-specific gene was detected in 3,030 ticks of H. longicornis.
Adult ; China ; Communicable Diseases ; Dry Ice ; Fever* ; Humans ; Japan ; Jeollanam-do* ; Korea* ; Larva ; Methods ; Nymph ; Orthobunyavirus ; Seasons ; Thrombocytopenia* ; Ticks* ; Weather

North Korea is located on the northern part of the Korean Peninsula in East Asia. While tick-borne pathogens of medical and veterinary importance have been reported from China and South Korea, they have not been reported from North Korea. To screen for zoonotic tick-borne pathogens in North Korea, ticks were collected from domestic goats. A total of 292 (27 nymph, 26 male, 239 female) Haemaphysalis (H.) longicornis were collected and assayed individually for selected tick-borne pathogens. A total of 77 (26.4%) were positive for Anaplasma bovis, followed by Bartonella (B.) grahamii (15, 5.1%), Anaplasma phagocytophilum (12, 4.1%), Bartonella henselae (10, 3.4%), and Borrelia spp. (3, 1.0%) based on 16S ribosomal RNA and ITS species-specific nested polymerase chain reaction. Using the groEL-based nested PCR, a total of 6 and 1 H. longicornis were positive for B. grahamii and B. henselae, respectively. All products were sequenced and demonstrated 100% identity and homology with previously reported sequences from other countries in GenBank. This is the first report of the detection of tick-borne pathogens in the North Korea and suggests that farm animals may act as reservoirs for zoonotic tick-borne pathogens.
Anaplasma phagocytophilum ; Anaplasma* ; Animals, Domestic ; Bartonella henselae ; Bartonella* ; Borrelia* ; China ; Databases, Nucleic Acid ; Democratic People's Republic of Korea* ; Far East ; Goats* ; Humans ; Korea ; Male ; Nymph ; Polymerase Chain Reaction ; Prevalence* ; RNA, Ribosomal, 16S ; Ticks

An adult male rufous turtle dove, Streptopelia (S.) orientalis (Aves: Columbiformes), was found dead in Yorii-machi Town, Osato District 369-1217, Saitama Prefecture, Japan, and subjected to necropsy. A large number of immobile hypopi (deutonymphs) of the hypoderatid mite, Hypodectes (H.) propus (Acarina: Hypoderatidae), were found individually encapsulated subcutaneously primarily in the adipose tissue. The mites were 1.43 mm in length and 0.44 mm in width on average, and had provoked mild inflammatory reactions that predominantly manifested as foamy macrophages and lymphoplasmocytes. PCR analysis using ribosomal DNA extracted from paraffin-blocked tissues produced a 240 bp band specific for hypoderatids. Based on the morphological features (distinct coxal apodemes, especially in the anterior portion) and PCR-based findings, the hypopi were identified as H. propus. To the best of our knowledge, this is the first case describing the subcutaneous mite H. propus in a rufous turtle dove, S. orientalis, in Japan. This study also highlights the use of paraffin blocks as a source of tissue DNA for molecular evaluation.
Animals ; Bird Diseases/diagnosis/*parasitology/pathology ; Columbidae/*parasitology ; DNA, Ribosomal/genetics ; Formaldehyde/metabolism ; Japan ; Male ; Mite Infestations/diagnosis/parasitology/pathology/*veterinary ; Mites/growth & development/*physiology ; Nymph/growth & development/physiology ; Paraffin Embedding/veterinary ; Polymerase Chain Reaction/veterinary