Equine attachment site preferences and seasonality of common North American ticks: Amblyomma americanum, Dermacentor albipictus, and Ixodes scapularis.

BACKGROUND: Ticks are common on horses, but recent publications characterizing equine tick infestations in North America are lacking. METHODS: To further understand attachment site preferences of common ticks of horses, and to document the seasonality of equine tick infestation in northeastern Oklahoma, horses from eight farms were evaluated twice a month over a 1-year period. Each horse was systematically inspected beginning at the head and moving caudally to the tail. Attachment sites of ticks were recorded and all ticks collected were identified to species and stage. RESULTS: Horses (26 males and 62 females) enrolled in the study ranged in age from 1 to 23 years (mean = 12, 95% CI 11-13). A total of 2731 ticks were collected; 84.1% (74/88) of the horses were infested (median = 3 ticks) at one or more examinations. Five tick species were identified, including Amblyomma americanum (78.2%; 2136/2731), Ixodes scapularis (18.2%; 497/2731), Dermacentor albipictus brown variant (2.6%; 71/2731), Dermacentor variabilis (0.7%; 20/2731), and Amblyomma maculatum (0.3%; 7/231). Most ticks were adults (83.6%; 2282/2731), but immature A. americanum (436/2136; 20.4%), D. albipictus (12/71; 16.9%), and A. maculatum (n = 1) were occasionally recovered. Amblyomma americanum were most often attached to the inguinal area, and I. scapularis and D. albipictus were most commonly found on the chest and axillary region (P < 0.0001). Ticks were found on horses in every month of the year. The largest number of ticks (638/2731; 23.4%) were collected in May (P < 0.0001). Amblyomma americanum, primarily immature, was the only tick recovered in September, I. scapularis and D. albipictus predominated October through February, and both A. americanum and I. scapularis were common in March. In the warmer months, April through August, A. americanum was the most common tick, followed by D. variabilis and A. maculatum. CONCLUSIONS: This research confirms that ticks common on horses in North America have attachment site preferences and that ticks infest horses in Oklahoma throughout the year, including during the winter. Additional research is warranted to fully understand the risk these infestations pose to equine health.

Experimental study of micro-habitat selection by ixodid ticks feeding on avian hosts.

Mechanisms of on-host habitat selection of parasites are important to the understanding of host-parasite interactions and evolution. To this end, it is important to separate the factors driving parasite micro-habitat selection from those resulting from host anti-parasite behaviour. We experimentally investigated whether tick infestation patterns on songbirds are the result of an active choice by the ticks themselves, or the outcome of songbird grooming behaviour. Attachment patterns of three ixodid tick species with different ecologies and host specificities were studied on avian hosts. Ixodes arboricola, Ixodes ricinus and Ixodes frontalis were put on the head, belly and back of adult great tits (Parus major) and adult domestic canaries (Serinus canaria domestica) which were either restricted or not in their grooming capabilities. Without exception, ticks were eventually found on a bird's head. When we gave ticks full opportunities to attach on other body parts - in the absence of host grooming - they showed lower attachment success. Moreover, ticks moved from these other body parts to the host's head when given the opportunity. This study provides evidence that the commonly observed pattern of ticks feeding on songbirds' heads is the result of an adaptive behavioural strategy. Experimental data on a novel host species, the domestic canary, and a consistent number of published field observations, strongly support this hypothesis. We address some proximate and ultimate causes that may explain parasite preference for this body part in songbirds. The link found between parasite micro-habitat preference and host anti-parasite behaviour provides further insight into the mechanisms driving ectoparasite aggregation, which is important for the population dynamics of hosts, ectoparasites and the micro-pathogens for which they are vectors.

Distribution of Alaria spp. mesocercariae in waterfrogs.

The distribution of Alaria-spp.-mesocercariae within the host is relevant for the examination via Alaria spp. mesocercariae migration technique (AMT) regarding predilection sites and may indicate an interaction between parasite and host. Naturally Alaria-exposed frogs of Pelophylax species (n = 13) were examined for systemic distribution and localization-specific parasite density of Alaria spp. mesocercariae. The frogs were necropsied and their body was divided into the following localizations: inner organs, head, torso, forelimbs, and hind limbs. The localizations were analyzed individually and in toto using Alaria spp. mesocercariae migration technique. Our results showed neither statistical differences concerning the number of mesocercariae in the different localizations nor in respect of the rate of positive localizations. Therefore, an accumulation in a particular predilection site seems unlikely. Further research on a representative sample is necessary before final conclusions can be drawn.

Efficacy of a dinotefuran, pyriproxyfen and permethrin combination product against Ctenocephalides felis felis (Bouché, 1835) (Siphonaptera: Pulicidae) on artificially infested rabbits.

The aim of this study was to evaluate the efficacy of an insecticidal product in rabbits that combines the neonicotinoid dinotefuran with the pyrethroid permethrin plus the insect growth regulator pyriproxyfen. Adult New Zealand rabbits (n = 12) were infested with Ctenocephalides felis felis (50 males and 50 females per rabbit) at days -7, -2, +5, +12 and +19. The control group (n = 6) received no treatment and the treated group (n = 6) received the commercial formulation, indicated for use in dogs, which was applied topically on day 0. The animals were mechanically evaluated with combs (comb test), to assess pulicidal efficacy, on days -5, +2, +7, +14 and +21. All flea removals and counts were performed by region, following the order: head, ears, neck, forelegs, dorsum, abdomen, hind limbs and tail, in order to determine the preferred sites of parasitism by the C. felis felis flea in rabbits. The distribution of fleas prevailed in the head region (about 62%), followed by the neck and back (14 and 11%, respectively). The insecticidal efficacy was calculated using arithmetic means, showing effectiveness of 100% on days +2 and +7 and 82.2% and 81.6%, on days +14 and +21, respectively. Thus the present study has shown the combination to be a viable option in the treatment and control of rabbits infested by C. felis felis.

Head and neck myiasis: a case series and review of the literature.

OBJECTIVE: This study describes 9 cases of myiasis affecting the head and neck region and discusses the demographic distribution, treatment, clinical characteristics, and sequelae of the disease in light of the literature. STUDY DESIGN: The study was performed in 2 steps. In the first part, 9 cases seen over a period of 10 years at the Emergency Department of Hospital da Restauração in Brazil were studied. In the second part, a literature search was performed in PubMed for articles on head and neck myiasis published from 1975 to March 2017. RESULTS: The case series mainly consisted of male patients in their 30s. The palate was the most commonly affected site. Myiasis was caused by Cochliomyia hominivorax in all patients, who were treated by mechanical removal of the larvae and debridement of necrotic tissue, followed by oral ivermectin. All patients had sequelae resulting from bone destruction. CONCLUSIONS: Head and neck myiasis generally affects individuals with poor hygiene habits, drug users, and individuals with neurologic and psychosocial disorders. The treatment of choice is mechanical removal of larvae and surgical debridement combined with oral ivermectin. This study provides information that could help clinicians in the diagnosis and management of this condition.

A Case of Lagochilascariasis in Suriname with the Involvement of the ENT System and the Skull Base.

We describe a case of human lagochilascariasis, with skull-base involvement and a chronic and relapsing course after treatment. This rare parasitic infection is usually manifested in the head and neck area, characterized by progressive granulomatous inflammation and the formation of abscesses. Transmission to humans most likely occurs by the consumption of undercooked meat of wild rodents. On the basis of literature studies, we propose the most likely life cycle of the parasite that involves wild feline and rodent species, with humans as accidental hosts. Even in endemic areas, it is very difficult to recognize the disease at an early stage. Progression will eventually lead to involvement of the (central) nervous system, as described in our case. Treatment is often difficult and involves resection and prolonged treatment with anthelmintic drugs. Recurrences are not uncommon and at present, long-term oral administration of ivermectin seems to be the most effective treatment.

Molecular analysis of Dirofilaria repens removed from a subcutaneous nodule in a Japanese woman after a tour to Europe.

A premature female Dirofilaria species, subsequently identified as Dirofilaria repens by its morphological features and mitochondrial 12S ribosomal RNA (12S rRNA) gene sequence, was removed from a subcutaneous nodule of the right temporal region of the head in a Japanese woman 2 years after she noticed swelling of her left calf following an insect sting during a tour to Europe; headache symptoms were noticed a few months later. The sequences of the mitochondrial 12S rRNA and cytochrome c oxidase subunit I genes from the organism were almost identical to those of sequences AM779772 (100% homology, 337/337) and AM749233 (99.8% homology, 536/537) of D. repens isolated from humans in Italy. However, the phylogenetic position of the 18S rRNA-internal transcribed spacer 1-5.8S rRNA region was in the same cluster as that of sequence JX290195 of Dirofilaria sp. "hongkongensis" (96.7% homology, 348/360), which was recently reported from Hong Kong as a novel Dirofilaria species. Information on regional genetic variation in D. repens isolated from animals and humans remains scarce. We report the detailed genetic features of this filaria as a reference isolate from a specific endemic area, to enrich the genetic database of D. repens.

Metazoan parasites in the head region of the bullet tuna Auxis rochei (Osteichthyes: Scombridae) from the western Mediterranean Sea.

The head region of 72 bullet tuna Auxis rochei from the western Mediterranean Sea (south-east Spain and the Strait of Gibraltar) was examined for parasites. Seven metazoan species were found in the fish from south-east Spain: three monogeneans, two trematodes and two copepods, whereas only three species were isolated in the fish from the Strait of Gibraltar. A comparison of the levels of infection of the parasites according to fish size in south-east Spain showed that the prevalence of Didymozoon auxis and the mean abundance of Allopseudaxine macrova were higher in the larger hosts (range of fork length = 38-44 cm) than in the smaller ones (33-37 cm). A comparison of the parasite infections according to geographical region showed that the mean abundances of Nematobothriinae gen. sp. and Caligus bonito were higher in fish from south-east Spain than in those from the Strait of Gibraltar. A comparison of the parasite fauna of A. rochei from the Mediterranean Sea with the published data on Auxis spp. from the Atlantic, Indian and Pacific Oceans revealed the closest similarity between the Mediterranean A. rochei and the Atlantic A. thazard.

Parasites of the head of Scomber colias (Osteichthyes: Scombridae) from the western Mediterranean Sea.

The metazoan parasite assemblage of the head of 30 specimens of the Atlantic chub mackerel (Scomber colias) from the western Mediterranean Sea was analysed. Eight species of parasites were found, four mazocraeid monogeneans: Grubea cochlear (prevalence = 10%), Kuhnia scombercolias (59%), K. scombri (52%), Pseudokuhnia minor (86%); three didymozoid trematodes: Nematobothrium cf. faciale (21%), N. filiforme (41%), N. scombri (7%); and one laerneopodid copepod: Clavelissa scombri (7%). Results were compared with previously published data from 14 localities of the eastern Mediterranean Sea and the Atlantic Ocean, using non-parametric univariate and multivariate analyses, and the whole parasite fauna of S. colias was compared with that of the congeners (S. australasicus, S. japonicus and S. scombrus). Parasites showed to reflect the biogeographical and phylogenetic history of host. From a methodological point of view, the use of both non-parametric univariate and multivariate techniques proved to be effective tools to detect dissimilarities between parasite assemblages.

Interruption of Onchocerca volvulus transmission in Northern Venezuela.

BACKGROUND: Onchocerciasis is caused by Onchocerca volvulus and transmitted by Simulium species (black flies). In the Americas, the infection has been previously described in 13 discrete regional foci distributed among six countries (Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela) where more than 370,000 people are currently considered at risk. Since 2001, disease control in Venezuela has relied on the mass drug administration to the at-risk communities. This report provides empirical evidence of interruption of Onchocerca volvulus transmission by Simulium metallicum in 510 endemic communities from two Northern foci of Venezuela, after 10-12 years of 6-monthly Mectizan (ivermectin) treatment to all the eligible residents. METHODS: In-depth entomologic and epidemiologic surveys were serially conducted from 2001-2012 in selected (sentinel and extra-sentinel) communities from the North-central (NC) and North-east (NE) onchocerciasis foci of Venezuela in order to monitor the impact of ivermectin treatment. RESULTS: From 2007-2009, entomological indicators in both foci confirmed that 0 out of 112,637 S. metallicum females examined by PCR contained L3 infection in insect heads. The upper bound of the 95% confidence intervals of the infective rate of the vector reached values below 1% by 2009 (NC) and 2012 (NE). Additionally, after 14 (NC) and 22 (NE) rounds of treatment, the seasonal transmission potential (±UL CIs) of S. metallicum was under the critical threshold of 20 L3 per person per season. Serological analysis in school children < 15 years-old demonstrated that 0 out of 6,590 individuals were harboring antibodies to Ov-16. Finally, epidemiological surveys made during 2010 (NC) and 2012 (NE) showed no evidence of microfilariae in the skin and eyes of the population. CONCLUSIONS: These results meet the WHO criteria for absence of parasite transmission and disease morbidity in these endemic areas which represent 91% of the population previously at-risk in the country. Consequently, the two Northern foci are currently under post-treatment onchocerciasis surveillance status in Venezuela.

Host selection and parasite infection in Aedes taeniorhynchus, endemic disease vector in the Galápagos Islands.

Host selection in blood-sucking arthropods has important evolutionary and ecological implications for the transmission dynamics, distribution and host-specificity of the parasites they transmit. The black salt-marsh mosquito (Aedes taeniorhynchus Wiedemann) is distributed throughout tropical to temperate coastal zones in the Americas, and continental populations are primarily mammalphilic. It is the only indigenous mosquito in the Galápagos Islands, having colonised the archipelago around 200,000 years ago, potentially adapting its host selection, and in the process, altering the dynamics of vector mediated pathogen interactions in the archipelago. Here, we use blood-meal analysis and PCR-based parasite screening approach to determine the blood-feeding patterns of A. taeniorhynchus in the Galápagos Islands and identify potential parasite transmission with which this mosquito could be involved. Our results show that A. taeniorhynchus feeds equally on mammals and reptiles, and only one avian sample was observed in 190 successful PCR amplifications from blood meals. However, we detected endemic filarial worms and Haemoproteus parasites known to infect various Galápagos bird species in mosquito thoraces, suggesting that feeding on birds must occur at low frequency, and that A. taeniorhynchus may play a role in maintaining some avian vector-borne pathogens, although more work is needed to explore this possibility. We also isolated three different DNA sequences corresponding to hemogregarine parasites of the genus Hepatozoon from mosquito and iguana blood samples, suggesting that more than one species of Hepatozoon parasites are present in Galápagos. Phylogenetic analysis of Hepatozoon 18sRNA sequences indicates that A. taeniorhynchus may have facilitated a recent breakdown in host-species association of formerly isolated Hepatozoon spp. infecting the reptile populations in the Galápagos Islands.

Henneguya cartilaginis n. sp. (Myxozoa: Myxosporea) in the head cartilage of masu salmon Oncorhynchus masou masou.

Henneguya cartilaginis n. sp. (Myxozoa: Myxosporea) is described from wild masu salmon Oncorhynchus masou masou in Hokkaido, Japan. H. cartilaginis n. sp. produced white cysts, up to 3mm in size, in the head of masu salmon. Infected fish exhibited cranial protrusion due to the cysts. Spores (11.4 × 8.6 µm) of H. cartilaginis n. sp. were egg-shaped with the posterior end more pointed and possessed two caudal appendages (34.2 µm average length). Histological observations revealed that large plasmodia possessing fine fibrous pseudopodia on the surface developed in the head cartilage. H. cartilaginis n. sp. resembles H. cerebralis, which was described from the cranial cartilage of Kosogol grayling Thymallus nigrescens in Mongolia. However, they were distinguishable by spore morphology. Molecular analysis of the 18S rDNA sequences indicated that H. cartilaginis n. sp. was most closely related to Henneguya zschokkei, H. nuesslini and H. salminicola of salmonid fish, with genetic similarities of 95.3%, 95.1% and 93.9%, respectively. Based on these differences in spore morphology, molecular data, the site of infection and geographical distribution, the present species is considered to be a new species.

Knowledge, attitudes and practices regarding head lice infestations in rural Nigeria.

INTRODUCTION: Head lice infestations are common in sub-Saharan Africa, but knowledge, attitudes and practices have never been studied in this region. METHODOLOGY: This population-based study was conducted in a small rural community (population = 590) in Kwara State, Central Nigeria. Inhabitants of the community were interviewed regarding head lice infestations, using a pre-tested structured questionnaire, and examined regarding the presence of active pediculosis. RESULTS: Of the 496 participants included, 367 (74.0%) had experienced head lice infestations, but only 26 (11.1%) of the individuals older than 15 years knew the correct mode of transmission. Of 142 individuals with active pediculosis, only 1 (0.7%) felt ashamed. Treatment was most commonly done by grooming (46.3%), followed by combing (27.2%). Only 4.6% used pediculicides, and 21.8% did not apply any treatment. Opinions about difficulties in controlling head lice were asked in three groups: biological, technical and social. In the first group, the most common difficulty noted was detecting head lice (52.1%), followed by possible resistance that would lengthen the time of infestation (38.9%). Technical constraints included concerns on the safety and effectiveness of products (48.7%) and difficulties in obtaining treatment (46.2%). Social contraints included difficulty in treating children (24.4%), lack of knowledge (23.5%), and the social behavior of children (22.2%). CONCLUSIONS: Head lice were not perceived as an important disease in a rural Nigerian community, and feelings about the infestation were mostly indifferent. Despite its common occurrence, knowledge on head lice was limited.  

False positive circumsporozoite protein ELISA: a challenge for the estimation of the entomological inoculation rate of malaria and for vector incrimination.

BACKGROUND: The entomological inoculation rate (EIR) is an important indicator in estimating malaria transmission and the impact of vector control. To assess the EIR, the enzyme-linked immunosorbent assay (ELISA) to detect the circumsporozoite protein (CSP) is increasingly used. However, several studies have reported false positive results in this ELISA. The false positive results could lead to an overestimation of the EIR. The aim of present study was to estimate the level of false positivity among different anopheline species in Cambodia and Vietnam and to check for the presence of other parasites that might interact with the anti-CSP monoclonal antibodies. METHODS: Mosquitoes collected in Cambodia and Vietnam were identified and tested for the presence of sporozoites in head and thorax by using CSP-ELISA. ELISA positive samples were confirmed by a Plasmodium specific PCR. False positive mosquitoes were checked by PCR for the presence of parasites belonging to the Haemosporidia, Trypanosomatidae, Piroplasmida, and Haemogregarines. The heat-stability and the presence of the cross-reacting antigen in the abdomen of the mosquitoes were also checked. RESULTS: Specimens (N=16,160) of seven anopheline species were tested by CSP-ELISA for Plasmodium falciparum and Plasmodium vivax (Pv210 and Pv247). Two new vector species were identified for the region: Anopheles pampanai (P. vivax) and Anopheles barbirostris (Plasmodium malariae). In 88% (155/176) of the mosquitoes found positive with the P. falciparum CSP-ELISA, the presence of Plasmodium sporozoites could not be confirmed by PCR. This percentage was much lower (28% or 5/18) for P. vivax CSP-ELISAs. False positive CSP-ELISA results were associated with zoophilic mosquito species. None of the targeted parasites could be detected in these CSP-ELISA false positive mosquitoes. The ELISA reacting antigen of P. falciparum was heat-stable in CSP-ELISA true positive specimens, but not in the false positives. The heat-unstable cross-reacting antigen is mainly present in head and thorax and almost absent in the abdomens (4 out of 147) of the false positive specimens. CONCLUSION: The CSP-ELISA can considerably overestimate the EIR, particularly for P. falciparum and for zoophilic species. The heat-unstable cross-reacting antigen in false positives remains unknown. Therefore it is highly recommended to confirm all positive CSP-ELISA results, either by re-analysing the heated ELISA lysate (100 °C, 10 min), or by performing Plasmodium specific PCR followed if possible by sequencing of the amplicons for Plasmodium species determination.

Primary subcutaneous hydatid cysts: a review of 22 cases.

AIM: We aimed to review cases of primary subcutaneous hydatid cysts whether this is a fearsome disease or a benign progressed pathology. These cysts are rare, have difficulty in diagnosis and management, particularly for inexperienced clinicians. METHODS: We searched key words of "echinococcosis, hydatid, soft tissue, subcutaneous, cutaneous" at MEDLINE/PUBMED. We eliminated unrelated articles, cases with primary visceral hydatid focus or muscular cysts. Twenty publications including 22 patients were suitable for analysis. We contacted with authors of the articles for missing data. Follow-up periods and recurrences were updated. RESULTS: All patients were from endemic areas and most from rural regions (90%). Most frequent locations were thigh (27%) and gluteal region (9%). Mean size was 5.7 + 3.1 cm (2-15 cm). Main symptom (70%) was painless, slow growing mass with normal overlying skin. Serologic tests were usually negative (79%). Only 45% of the patients were diagnosed as hydatid cyst before treatment. Most cases (91%) were treated by surgical excision and spillage occurred at 25% of them. Cyst pouchs were irrigated with protoscolocidal solutions after cyst removal. There was no anaphylaxis during procedures. There was no recurrence with a mean follow-up of 26 + 18 months (6-60 months). CONCLUSION: Primary subcutaneous hydatid cyst should be in mind for differential diagnosis of soft tissue masses particularly for patients who lived in regions where hydatid cyst is endemic. There is no reported anaphylaxis or recurrence during diagnostic or therapeutic interventions. Complete excision is the best treatment option. Primary subcutaneous hydatid cysts generally look like a benign progressed disease.

[Description of Trochilopsylla torresmurai n. gen., n. sp. (Siphonaptera: Ceratophyllidae) from Chile, the first flea known to parasitize a humming bird (Aves: Trochilidae)]. / Description de Trochilopsylia torresmurai n. gen., n. sp. (Siphonaptera : Ceratophyllidae) du Chiu, première mention d'une puce parasite d'oiseau-mouche (Aves : Trochiudae).

A new genus and a new species are described from fleas of occupied nest from humming bird, Oreotrichulus estella (d'Orbigny & Lafresnaye, 1838). This taxa shows, in particular, some affinities with Dasypsyllus Baker, 1908, parasite on birds, cosmopolitan except in afrotropical and austral regions, and Smitipsylla Lewis, 1971, parasite on flying squirrels (Anomaluridae) in oriental region.

Malaria vector surveillance in Ganghwa-do, a malaria-endemic area in the Republic of Korea.

We investigated the seasonality of Anopheles mosquitoes, including its species composition, density, parity, and population densities of mosquitoes infected with the parasite in Ganghwa-do (Island), a vivax malaria endemic area in the Republic of Korea. Mosquitoes were collected periodically with a dry-ice-tent trap and a blacklight trap during the mosquito season (April-October) in 2008. Anopheles sinensis (94.9%) was the most abundant species collected, followed by Anopheles belenrae (3.8%), Anopheles pullus (1.2%), and Anopheles lesteri (0.1%). Hibernating Anopheles mosquitoes were also collected from December 2007 to March 2008. An. pullus (72.1%) was the most frequently collected, followed by An. sinensis (18.4%) and An. belenrae (9.5%). The composition of Anopheles species differed between the mosquito season and hibernation seasons. The parous rate fluctuated from 0% to 92.9%, and the highest rate was recorded on 10 September 2008. Sporozoite infections were detected by PCR in the head and thorax of female Anopheles mosquitoes. The annual sporozoite rate of mosquitoes was 0.11% (2 of 1,845 mosquitoes). The 2 mosquitoes that tested positive for sporozoites were An. sinensis. Malarial infections in anopheline mosquitoes from a population pool were also tried irrespective of the mosquito species. Nine of 2,331 pools of Anopheles mosquitoes were positive. From our study, it can be concluded that An. sinensis, which was the predominant vector species and confirmed as sporozoite-infected, plays an important role in malaria transmission in Ganghwa-do.

Malaria Vector Surveillance in Ganghwa-do, a Malaria-Endemic Area in the Republic of Korea

We investigated the seasonality of Anopheles mosquitoes, including its species composition, density, parity, and population densities of mosquitoes infected with the parasite in Ganghwa-do (Island), a vivax malaria endemic area in the Republic of Korea. Mosquitoes were collected periodically with a dry-ice-tent trap and a blacklight trap during the mosquito season (April-October) in 2008. Anopheles sinensis (94.9%) was the most abundant species collected, followed by Anopheles belenrae (3.8%), Anopheles pullus (1.2%), and Anopheles lesteri (0.1%). Hibernating Anopheles mosquitoes were also collected from December 2007 to March 2008. An. pullus (72.1%) was the most frequently collected, followed by An. sinensis (18.4%) and An. belenrae (9.5%). The composition of Anopheles species differed between the mosquito season and hibernation seasons. The parous rate fluctuated from 0% to 92.9%, and the highest rate was recorded on 10 September 2008. Sporozoite infections were detected by PCR in the head and thorax of female Anopheles mosquitoes. The annual sporozoite rate of mosquitoes was 0.11% (2 of 1,845 mosquitoes). The 2 mosquitoes that tested positive for sporozoites were An. sinensis. Malarial infections in anopheline mosquitoes from a population pool were also tried irrespective of the mosquito species. Nine of 2,331 pools of Anopheles mosquitoes were positive. From our study, it can be concluded that An. sinensis, which was the predominant vector species and confirmed as sporozoite-infected, plays an important role in malaria transmission in Ganghwa-do.

Epidemiology of Oestrus ovis infestations in sheep in Kars province of north-eastern Turkey.

This study was carried out to determine the prevalence of cavical myiasis caused by Oestrus ovis larvae in sheep of Kars province of north-eastern part of Turkey. From 30 to 35 sheep heads (total of 387) were examined every month regularly for O. ovis larvae during 12 months. Of 387 heads, 156 (%40.3) were infested with O. ovis larvae.. The prevalence of nasal myiasis was 54.3% in spring, 41% in summer, 28% in fall, and 38.9% in winter. The differences among seasons were significant statistically (P<0.05). Infestation rate up to 1-years-old was 30.0%, 1 to 3 years-old 40.0% and older than 3 years old was 52.4%. The number of larvae made peak in spring months and went down in the months of fall. The mean number of larvae regarding examined animals was 1.8, and the mean according to infested animals was 4.5. Density of O.ovis larvae in infested sheep were changed from 1 to 31. Infestation rate in the morkaraman breed was higher (43.4%) comparing to the rate in the akkaraman breed (31.3%). The differences between sheep breed were also significant (p<0.05). Sheep with dark colored head had higher infestation rate than that of sheep with light colored head (p<0.05).