Cardio-pulmonary nematodes of the red fox (Vulpes vulpes) of Sardinia, Italy.

Cardio-pulmonary parasites, such as Angiostrongylus vasorum, Crenosoma vulpis, and Eucoleus aerophilus, pose a significant concern on account of pulmonary and cardiac problems they induce in dogs. While the red fox is known to be a key reservoir host for A. vasorum and may also play a role in transmitting C. vulpis and E. aerophilus, there has been no recent research on these parasites in foxes from Sardinia, with the most current studies dating back to 1986. A survey was conducted on red foxes in Sardinia, where a total of 51 foxes were collected, necropsied, and examined for adult worms in their hearts and lungs. The worms were identified using morphometric analysis and molecular methods. The results showed a 54.9% overall prevalence at dissection: 45.1% of the foxes were positive for E. aerophilus, 17.6% for C. vulpis, and 13.7% for A. vasorum. The molecular analyses validated the morphological characterization. In comparison to previous research, which found 13 out of 85 foxes to be positive for A. vasorum with a prevalence rate of 15.3% and 1 for E. aerophilus with a prevalence of 1.2%, this study showed an increased prevalence of E. aerophilus and C. vulpis, and a decrease in the prevalence of A. vasorum. These results indicate that the red foxes in Sardinia represent a reservoir host for cardio-pulmonary nematodes and it should be considered in the differential diagnosis of respiratory distress syndrome in dogs.

Angiostrongylus cantonensis in North African hedgehogs as vertebrate hosts, Mallorca, Spain, October 2018.

In October 2018, two Atelerix algirus hedgehogs were admitted to the Wildlife Rehabilitation Hospital in Mallorca (Balearic Islands, Spain) with signs of acute neurological disease. Necropsy detected immature, fully developed nematodes in the subarachnoid space of both hedgehogs, including a gravid female worm. DNA-based molecular tools confirmed the nematode as Angiostrongylus cantonensis, an important aetiological agent of eosinophilic meningitis in humans. So far this zoonotic parasite in has not been reported in western European wildlife.

Nematode parasites in young cattle: what role for unexpected species?

AIMS To investigate the timing of infection of beef calves with sheep nematode species on three sheep and beef farms, and to determine the prevalence of cross-infection in calves before weaning across a larger number of farms. METHODS Farms in the Far North, Gisborne and Tararua districts, in the North Island of New Zealand, were enrolled in 2014. Fresh faecal samples were collected from approximately 10 calves on each farm between birth and up to 5 months after weaning. In 2016, faecal samples were collected from calves before weaning from 22 farms across the upper North Island. For both trials faecal samples were assessed for faecal nematode egg counts and cultured to determine parasite genus. For samples from the three farms, larvae were identified to species using a multiplex PCR assay. RESULTS On the three farms, the median percentage of sheep nematode species detected in faecal cultures was 25 (min 3, max 77)%. The main sheep species detected were Cooperia curticei and Haemonchus spp. (putatively contortus). In faecal samples collected before weaning from 22 farms, Haemonchus spp. were present in 19/22 samples, and the median prevalence was 15 (min 0, max 73)% of the total larvae cultured. CONCLUSIONS AND CLINICAL RELEVANCE The implications of sheep nematode species being present in calves should be considered by farmers and veterinarians when undertaking anthelmintic efficacy testing, as they may contribute to false conclusions regarding anthelmintic efficacy. Pre-weaning calves may also be a possible source of contamination and/or refugia for Haemonchus spp. on farms and should be considered when developing parasite control plans for sheep.

Bulimulus tenuissimus (mollusca) as a new potential host of Angiostrogylus cantonensis (nematoda), a histological and metabolic study.

The terrestrial gastropod Bulimulus tenuissimus is widespread in South America. It is an intermediate host of many parasites, but there are no records of infection of this snail by Angiostrongylus cantonensis, despite the occurrence of this parasite and angiostrongyliasis cases in the same areas in which B. tenuissimus occurs. For this reason, it is important investigate the susceptibility of B. tenuissimus to A. cantonensis-infection, since it can be used as intermediate host of A. cantonensis, increasing the list of terrestrial gastropods that infect wild and domestic animals and humans with this parasite. The purpose of this study was to evaluate the susceptibility of B. tenuissimus to experimental infection with L1 larvae of A. cantonensis. The snails were exposed to 1200 L1 larvae and it was possible observe many developing larvae in the cephalopedal mass and mantle tissues, with intense hemocyte infiltration and collagen deposition, but no typical granuloma structures were formed. The glucose content and lactate dehydrogenase activity in the hemolymph varied, indicating an increase of anaerobic energy metabolism in the middle of infection, but with a tendency to return to normal values at the end of pre-patent period. This was corroborated by the marked reduction in the glycogen content in the cephalopedal mass and digestive gland in the first and second week after exposure, followed by a slight increase in the third week. The content of pyruvic acid in the hemolymph was 14.84% lower at the end of pre-patent period, and oxalic acid content was 41.14% higher. These results indicate an aerobic to anaerobic transition process. The PAS reaction showed a large amount of glycogen inside the developing larvae and muscular tissues of the cephalopedal mass, indicating that despite the high consumption of this polysaccharide by the parasite, the snail is able to maintain its energy metabolism based on carbohydrates. The results reveal that B. tenuissimus is a robust host, which can live with the developing larvae of A. cantonensis and overcome the metabolic damages resulting from parasitism.

Environmentally transmitted parasites: Host-jumping in a heterogeneous environment.

Groups of chronically infected reservoir-hosts contaminate resource patches by shedding a parasite׳s free-living stage. Novel-host groups visit the same patches, where they are exposed to infection. We treat arrival at patches, levels of parasite deposition, and infection of the novel host as stochastic processes, and derive the expected time elapsing until a host-jump (initial infection of a novel host) occurs. At stationarity, mean parasite densities are independent of reservoir-host group size. But within-patch parasite-density variances increase with reservoir group size. The probability of infecting a novel host declines with parasite-density variance; consequently larger reservoir groups extend the mean waiting time for host-jumping. Larger novel-host groups increase the probability of a host-jump during any single patch visit, but also reduce the total number of visits per unit time. Interaction of these effects implies that the waiting time for the first infection increases with the novel-host group size. If the reservoir-host uses resource patches in any non-uniform manner, reduced spatial overlap between host species increases the waiting time for host-jumping.

Scarabaeus cristatus (Coleoptera: Scarabaeidae) as intermediate host of Physocephalus dromedarii (Nematoda: Spirocercidae)--a contribution to the epidemiology of camel physocephalidosis.

In UAE, camel Physocephalus dromedarii was diagnosed for the first time in 2011 in dromedaries from a farm that previously had imported animals from foreign countries. The large scarab beetle, Scarabaeus cristatus, was found to be the major intermediate host for this parasite in Dubai. A total of 638 specimens of S. cristatus were collected and examined for the presence of third-stage larvae of nematode larvae at two sites in the Dubai Emirate (Emirates Industry for Camel Milk and Products and horse endurance training track) within a distance of 15 km. Third-stage larvae of P. dromedarii were detected in 94 and 97 % of beetles collected from the territory of the camel milk farm and the endurance training track, respectively. In addition to third-stage larvae, 264 beetles contained second-stage larvae. Only four beetles were infected with other than P. dromedarii larvae. The average larval burden in beetles from camel milk farm was significantly higher compared to those in beetles collected from the other site (1538 vs. 697). Comparison of larval burdens in juvenile and adult beetles collected at the camel milk farm showed a significantly higher intensity in adult specimens (501 vs. 1734) while in beetles found on the horse endurance track, larval burdens were comparable (548 vs. 858). The results suggest that S. cristatus become infected at the camel milk farm, and in search for other sources of food, they fly to places where they were found feeding on feces of other animals.

Number of Grooming Partners Is Associated with Hookworm Infection in Wild Vervet Monkeys (Chlorocebus aethiops).

There are many known benefits of social grooming among primates, including maintenance of social relationships, removal of ectoparasites, and improved physiological condition. Recently, however, researchers have noted that social grooming and social contact may also present a significant cost by facilitating transmission of some parasites and pathogens. We investigated whether the number of social grooming partners varied based on infection status for gastrointestinal parasites. We used focal animal sampling and continuous recording to collect data on the number of grooming partners for known individual vervet monkeys (Chlorocebus aethiops). We collected non-invasive faecal samples and examined them using faecal flotation, faecal sedimentation, and immunofluorescence microscopy. We detected 6 parasites: Trichuris sp. (92%), hookworm (71%), spirurids (68%), Oesophagostomum sp. (84%), Strongyloides sp. (24%), and Entamoeba coli (92%). The number of grooming partners varied significantly based on infection with hookworm and sex. No significant relationships were detected for other parasites. Associations between host behavioural variation and some parasite taxa (specifically Trichuris, Oesophagostomum, and Entamoeba spp.) were impossible to explore due to an extremely high prevalence among hosts. This is the first report that we are aware of that has detected an association between social grooming behaviours and infection with hookworm.

Water, sanitation, hygiene, and soil-transmitted helminth infection: a systematic review and meta-analysis.

BACKGROUND: Preventive chemotherapy represents a powerful but short-term control strategy for soil-transmitted helminthiasis. Since humans are often re-infected rapidly, long-term solutions require improvements in water, sanitation, and hygiene (WASH). The purpose of this study was to quantitatively summarize the relationship between WASH access or practices and soil-transmitted helminth (STH) infection. METHODS AND FINDINGS: We conducted a systematic review and meta-analysis to examine the associations of improved WASH on infection with STH (Ascaris lumbricoides, Trichuris trichiura, hookworm [Ancylostoma duodenale and Necator americanus], and Strongyloides stercoralis). PubMed, Embase, Web of Science, and LILACS were searched from inception to October 28, 2013 with no language restrictions. Studies were eligible for inclusion if they provided an estimate for the effect of WASH access or practices on STH infection. We assessed the quality of published studies with the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. A total of 94 studies met our eligibility criteria; five were randomized controlled trials, whilst most others were cross-sectional studies. We used random-effects meta-analyses and analyzed only adjusted estimates to help account for heterogeneity and potential confounding respectively. Use of treated water was associated with lower odds of STH infection (odds ratio [OR] 0.46, 95% CI 0.36-0.60). Piped water access was associated with lower odds of A. lumbricoides (OR 0.40, 95% CI 0.39-0.41) and T. trichiura infection (OR 0.57, 95% CI 0.45-0.72), but not any STH infection (OR 0.93, 95% CI 0.28-3.11). Access to sanitation was associated with decreased likelihood of infection with any STH (OR 0.66, 95% CI 0.57-0.76), T. trichiura (OR 0.61, 95% CI 0.50-0.74), and A. lumbricoides (OR 0.62, 95% CI 0.44-0.88), but not with hookworm infection (OR 0.80, 95% CI 0.61-1.06). Wearing shoes was associated with reduced odds of hookworm infection (OR 0.29, 95% CI 0.18-0.47) and infection with any STH (OR 0.30, 95% CI 0.11-0.83). Handwashing, both before eating (OR 0.38, 95% CI 0.26-0.55) and after defecating (OR 0.45, 95% CI 0.35-0.58), was associated with lower odds of A. lumbricoides infection. Soap use or availability was significantly associated with lower infection with any STH (OR 0.53, 95% CI 0.29-0.98), as was handwashing after defecation (OR 0.47, 95% CI 0.24-0.90). Observational evidence constituted the majority of included literature, which limits any attempt to make causal inferences. Due to underlying heterogeneity across observational studies, the meta-analysis results reflect an average of many potentially distinct effects, not an average of one specific exposure-outcome relationship. CONCLUSIONS: WASH access and practices are generally associated with reduced odds of STH infection. Pooled estimates from all meta-analyses, except for two, indicated at least a 33% reduction in odds of infection associated with individual WASH practices or access. Although most WASH interventions for STH have focused on sanitation, access to water and hygiene also appear to significantly reduce odds of infection. Overall quality of evidence was low due to the preponderance of observational studies, though recent randomized controlled trials have further underscored the benefit of handwashing interventions. Limited use of the Joint Monitoring Program's standardized water and sanitation definitions in the literature restricted efforts to generalize across studies. While further research is warranted to determine the magnitude of benefit from WASH interventions for STH control, these results call for multi-sectoral, integrated intervention packages that are tailored to social-ecological contexts.

Wild deer as potential vectors of anthelmintic-resistant abomasal nematodes between cattle and sheep farms.

Gastrointestinal (GI) nematodes are among the most important causes of production loss in farmed ruminants, and anthelmintic resistance is emerging globally. We hypothesized that wild deer could potentially act as reservoirs of anthelmintic-resistant GI nematodes between livestock farms. Adult abomasal nematodes and faecal samples were collected from fallow (n = 24), red (n = 14) and roe deer (n = 10) from venison farms and areas of extensive or intensive livestock farming. Principal components analysis of abomasal nematode species composition revealed differences between wild roe deer grazing in the areas of intensive livestock farming, and fallow and red deer in all environments. Alleles for benzimidazole (BZ) resistance were identified in ß-tubulin of Haemonchus contortus of roe deer and phenotypic resistance confirmed in vitro by an egg hatch test (EC50 = 0.149 µg ml(-1) ± 0.13 µg ml(-1)) on H. contortus eggs from experimentally infected sheep. This BZ-resistant H. contortus isolate also infected a calf experimentally. We present the first account of in vitro BZ resistance in wild roe deer, but further experiments should firmly establish the presence of phenotypic BZ resistance in vivo. Comprehensive in-field studies should assess whether nematode cross-transmission between deer and livestock occurs and contributes, in any way, to the development of resistance on livestock farms.

Helminths and helminthoses in Central Europe: diseases caused by nematodes (roundworms).

The third part of the overview "Helminths and helminthoses in Central Europe" deals with the medically relevant nematodes (roundworms) and nematode-caused diseases occurring in Central Europe. The paper comprises data on the biology of the parasites and their ways of transmission, describes the symptomatology of the diseases, summarizes the possibilities of diagnosis and refers to the prophylactic means.

Predicting and reducing potential parasite infection between migratory livestock and resident Asiatic ibex of Pin valley, India.

Disease cross-transmission between wild and domestic ungulates can negatively impact livelihoods and wildlife conservation. In Pin valley, migratory sheep and goats share pastures seasonally with the resident Asiatic ibex (Capra sibirica), leading to potential disease cross-transmission. Focussing on gastro-intestinal nematodes (GINs) as determinants of health in ungulates, we hypothesized that infection on pastures would increase over summer from contamination by migrating livestock. Consequently, interventions in livestock that are well-timed should reduce infection pressure for ibex. Using a parasite life-cycle model, that predicts infective larval availability, we investigated GIN transmission dynamics and evaluated potential interventions. Migratory livestock were predicted to contribute most infective larvae onto shared pastures due to higher density and parasite levels, driving infections in both livestock and ibex. The model predicted a c.30-day antiparasitic intervention towards the end of the livestock's time in Pin would be most effective at reducing GINs in both hosts. Albeit with the caveats of not being able to provide evidence of interspecific parasite transmission due to the inability to identify parasite species, this case demonstrates the usefulness of our predictive model for investigating parasite transmission in landscapes where domestic and wild ungulates share pastures. Additionally, it suggests management options for further investigation.

Control of soil-transmitted helminthiasis in Myanmar: results of 7 years of deworming.

After a baseline survey in 2003 which showed an overall parasitological prevalence of soil-transmitted helminths of 69.7% in school children (prevalence of ascariasis 48.5%, prevalence of trichuriasis 57.5% and prevalence of hookworm infection 6.5), a national deworming programme was established. After 7 years of implementation, it had resulted in a significant reduction of STH prevalence (prevalence of any STH 21%, prevalence of ascariasis 5.8%, prevalence of trichuriasis 18.6% and prevalence of hookworm infection 0.3%) as well as a reduction of the infections of moderate-heavy intensity from 18.5% at baseline to less than 7%. The results are encouraging and a reduction of the frequency of deworming can be envisaged in two of four ecological areas of Myanmar.

Cross transmission of gastrointestinal nematodes between captive neotropical felids and feral cats.

Pathogen cross transmission between wildlife and domestic animals represents an extinction risk for wildlife; however, reliable verification is difficult to perform, and in some cases, it is even considered unlikely to be conducted. The aim of this work was to identify cross transmission of helminths between feral cats and captive wild felids at a zoological park in southeastern Mexico. Feces were collected from jaguars (Panthera onca), cougars (Puma concolor), ocelots (Leopardus pardalis), margays (Leopardus wiedii), and jaguarundis (Puma yagouaroundi). A flotation technique and macroscopic sieving were performed on the feces. Additionally, as part of the noxious fauna control program of the park, feral cats were captured and euthanized. To perform parasitologic studies, helminths from these animals were recovered. Toxocara cati and Trichuris campanula were shared by jaguarundis and feral cats. Ancylostoma sp. was found in jaguar and ocelot and Ancylostoma tubaeforme in feral cats. Additionally, during this study, a couple of jaguarundis died with clinical signs of trichuriasis. This is the first report of T. campanula in jaguarundi. Because feral cats roam freely in the park, transmission could occur from these vertebrates to wild felids. This study shows the risk that parasites represent to wild felids; a similar situation could be found in free-living species, especially in fragmented habitats that favor contact with domestic animals.

Effect of sanitation on soil-transmitted helminth infection: systematic review and meta-analysis.

BACKGROUND: In countries of high endemicity of the soil-transmitted helminth parasites Ascaris lumbricoides, Trichuris trichiura, and hookworm, preventive chemotherapy (i.e., repeated administration of anthelmintic drugs to at-risk populations) is the main strategy to control morbidity. However, rapid reinfection of humans occurs after successful deworming, and therefore effective preventive measures are required to achieve public health goals with optimal efficiency and sustainability. METHODS AND FINDINGS: We conducted a systematic review and meta-analysis to assess the effect of sanitation (i.e., access and use of facilities for the safe disposal of human urine and feces) on infection with soil-transmitted helminths. PubMed, Embase, ISI Web of Science, and the World Health Organization Library Database were searched without language restrictions and year of publication (search performed until December 31, 2010). Bibliographies of identified articles were hand-searched. All types of studies reporting data on sanitation availability (i.e., having access at own household or living in close proximity to sanitation facility), or usage, and soil-transmitted helminth infections at the individual level were considered. Reported odds ratios (ORs) of the protective effect of sanitation on soil-transmitted helminth infections were extracted from the papers or calculated from reported numbers. The quality of published studies was assessed with a panel of criteria developed by the authors. Random effects meta-analyses were used to account for observed heterogeneity. Thirty-six publications, consisting of 39 datasets, met our inclusion criteria. Availability of sanitation facilities was associated with significant protection against infection with soil-transmitted helminths (OR  =  0.46 to 0.58). Regarding the use of sanitation, ORs of 0.54 (95% confidence interval [CI] 0.28-1.02), 0.63 (95% CI 0.37-1.05), and 0.78 (95% CI 0.60-1.00) were determined for T. trichiura, hookworm, and A. lumbricoides, respectively. The overall ORs, combining sanitation availability and use, were 0.51 (95% CI 0.44-0.61) for the three soil-transmitted helminths combined, 0.54 (95% CI 0.43-0.69) for A. lumbricoides, 0.58 (95% CI 0.45-0.75) for T. trichiura, and 0.60 (95% CI 0.48-0.75) for hookworm. CONCLUSIONS: Despite a number of limitations (e.g., most studies used a cross-sectional design and were of low quality, with potential biases and considerable heterogeneity), our results reveal that sanitation is associated with a reduced risk of transmission of helminthiases to humans. Access to improved sanitation should be prioritized alongside preventive chemotherapy and health education to achieve a durable reduction of the burden of helminthiases.

[Surveillance on the prevalence of soil-transmitted nematode infection in Fujian in 2006-2010].

OBJECTIVE: To analyze the prevalent trend of soil-transmitted nematode infection in Fujian Province during the past 5 year surveillance and evaluate the control effect. METHODS: From 2006 to 2010, fecal samples of the inhabitants of 3 years old and above were collected every November and examined for intestinal helminth eggs by the modified Kato s thick smear technique at the 2 surveillance sites: Punan village of Zhangzhou and Gushan village of Shaowu. Cellophane tapes were used to detect pinworm eggs for children aged 3-12. Soil samples were also collected from vegetable field, lavatory, courtyard and kitchen of 20 randomly selected families (in 2 villages) each with stool egg-positive findings and examined for ascaris eggs by a modified saturated sodium nitrate floatation method. RESULTS: The prevalence of soil-transmitted nematode infection at the surveillance sites decreased from 45.3% (946/2087) in 2006 to 15.1% (226/1494) in 2010, with a reduction of 66.6%. Among the infected subjects, hookworm infection occupied 75%-85%, while ascaris or trichuris infections each accounted for less than 10%. In terms of infection intensity, 65.2%-85.5% of the hookworm infection was light, and majority of the infected subjects were farmers. The pinworm prevalence in children were still high although it had dropped down from 46.1% (140/304) in 2006 to 29.8% (36/121) in 2010, declined by 35.4%. In the 5 years, totally 400 soil samples from 100 families were examined and 21 samples were found ascaris egg positive with viable eggs in only one sample. CONCLUSION: The 5 year surveillance reveals a decreasing trend of the soil-transmitted nematode prevalence but shows a relatively high hookworm infection rate in the population and pinworm infection in children.

Soil transmitted helminths and schistosoma mansoni infections among school children in Zarima town, northwest Ethiopia.

BACKGROUND: In Ethiopia, because of low quality drinking water supply and latrine coverage, helminths infections are the second most predominant causes of outpatient morbidity. Indeed, there is a scarcity of information on the prevalence of soil transmitted helminths and Schistosomiasis in Ethiopia, special in study area. Therefore, the aim of this study was to determine the prevalence and associated risk factors of soil transmitted helminths and intestinal Schistosomiasis. METHODS: Cross-sectional study was conducted among 319 school children of Zarima town from April 1 to May 25, 2009. A pre-tested structured questionnaire was used to collect socio-demographic data and possible risk factors exposure. Early morning stool samples were collected and a Kato Katz semi concentration technique was used to examine and count parasitic load by compound light microscope. Data entry and analysis was done using SPSS-15 version and p-value < 0.05 considered statistically significant. RESULTS: Out of 319 study subjects, 263 (82.4%) of the study participants infected with one or more parasites. From soil transmitted helminths, Ascaris lumbricoides was the predominant isolate (22%) followed by Hookworms (19%) and Trichuris trichiura (2.5%). Schistosoma mansoni was also isolated in 37.9% of the study participants. Hookworm and S. mansoni infections showed statistically significant associations with shoe wearing and swimming habit of school children, respectively. CONCLUSION: Prevalence of soil transmitted helminths (STH) and S.mansoni was high and the diseases were still major health problem in the study area which alerts public health intervention as soon as possible.

Soil-transmitted helminthiasis in rural south-west China: prevalence, intensity and risk factor analysis.

Only few studies in rural China have explored the epidemiology of intestinal helminth infections and identified risk factors for transmission. The study was carried out in Simao and Mengla counties, where single fecal samples were collected from 317 school-aged children and from 94 inhabitants of a single village. Fecal specimens were examined with the Kato-Katz thick smear method and examined for helminth eggs. Data regarding socio-demographic and behavioral risk factors were collected using questionnaires. In Simao County the overall soil-transmitted helminthes (STH) prevalence was 40.2% (2.7, 5.4 and 35.7% for ascariasis, trichuriasis and hookworm infection, respectively). The STH infection rates were significantly higher in Mengla County, with an overall prevalence of 68.3% (19.0, 34.6 and 47.3% for ascariasis, trichuriasis and hookworm infection, respectively). Females were less likely to be infected with Trichuris trichiura (OR 0.29; 95% CI 0.15-0.56) and with hookworms (OR 0.55; 95% CI 0.33-0.93) than males. Hookworm infections were more prevalent among those 12 years of age or older (OR 2.9; 95% CI 1.2-7.1). Children of mothers with educational attainment of secondary school or higher had a protective effect against T. trichiura (OR 0.18; 95% CI 0.06-0.54) and hookworm (OR 0.21; 95% CI 0.09-0.51) infections. In the village survey, hookworm was the most prevalent species (62.8%) with infection seen in those 50 years of age and older. Based on recommended intervention strategies by the World Health Organization, Simao County should opt for school-based deworming once each year, while Mengla County should implement a similar strategy biannually, but should include the elderly population.

A first report of Thelazia callipaeda infection in Phortica okadai and wildlife in national nature reserves in China.

BACKGROUND: Thelazia callipaeda is a zoonotic parasitic nematode of the family Thelaziidae, with Phortica okadai as its intermediate host and only confirmed vector in China. China has the largest number of human cases of thelaziosis in the world. It is generally believed that infected domestic animals (dogs and cats) are the most important reservoir hosts of T. callipaeda, and thus pose a direct threat to humans. At present, there is little research or attention focused on the role of wildlife in the transmission cycle of thelaziosis in nature reserves. METHODS: We selected locations in four national nature reserves across China to monitor P. okadai and wildlife. We used a fly-trap method to monitor P. okadai density. Morphological analysis of the parasites collected from the conjunctival sac of the infected wildlife was undertaken as the first step in species identification, and polymerase chain reaction (PCR) was used for species confirmation. RESULTS: In 2019, the density of P. okadai in Foping National Nature Reserve in China increased sharply, and infected P. okadai were newly found in the reserve. Giant panda, wild boar, leopard cat, and black bear were found to be newly infected with T. callipaeda (one individual of each species). A total of four worms were collected, one from each species of wildlife. The four worms were identified as T. callipaeda by their morphological characteristics; species identification was confirmed by PCR amplification. CONCLUSIONS: To the best of our knowledge, this is the first report of T. callipaeda infection in P. okadai as well as in a variety of wildlife, including giant panda, in nature reserves in China. These results indicate that there is a transmission cycle of T. callipaeda among wildlife in these nature reserves. The increasing number of case reports of thelaziosis in wildlife suggest a likely risk of T. callipaeda infection for the inhabitants of villages situated around nature reserves.

Aquatic molluscs as auxiliary hosts for terrestrial nematode parasites: implications for pathogen transmission in a changing climate.

Nematodes are common parasites of molluscs but are often overlooked. Both metastrongyloid and rhabditoid species dominate the fauna within land snail and slug populations. Nevertheless, a key characteristic of many laboratory studies is the ability of these terrestrial nematodes to utilize aquatic molluscs as auxiliary hosts. The significance of this to the ecology of the parasite has never been evaluated. There is increasing concern as to the impact of climate change on the epidemiology of many parasitic diseases. In particular, it has been suggested that host switching may increase under the pressure of extreme climatic conditions. It is therefore timely to assess the role that aquatic molluscs may play in transmitting terrestrial nematodes, which include species of medical and veterinary importance such as Angiostrongylus cantonensis, A. vasorum, and Muellerius capillaris. The present review assesses the mechanisms of terrestrial nematode transmission through aquatic molluscs focusing on metastrongyloid and rhabditoid species, the importance of variable susceptibility of molluscan hosts, field studies on natural occurrence within aquatic habitats, and the impact of extreme climatic events (floods and droughts) that may increase in frequency under climate change.

[Epidemiology of soil-transmitted nematode infections in central mountain area of Hainan province].

The epidemiology of soil-transmitted intestinal nematodes were observed in the central mountain area without anti-helminthic therapy from 1986 to 2008. The results showed that the overall prevalence decreased from 96.4% in 1986 to 35.7% in 2008. The prevalence of Ancylostoma duodenale, Ascaris lumbricoides and Trichuris trichiura decreased from 84.7%. 80.9%, 31.8% in 1986 to 32.5%, 0.3%, 4.2% in 2008, respectively. The proportion of light infection with Ancylostoma duodenale, Ascaris lumbricoides and Trichuris trichiura increased from 56.6%, 41.2%, and 66.9% in 1986 to 97.9%, 100%, and 83.7% in 2008, respectively. While that of heavy infection decreased from 6.8%, 11.9%, and 3.8% in 1986 all to zero in 2008. Water and toilet renovation, rural income increase and the improvement of sanitation and living conditions made the prevalence of soil-transmitted intestinal nematode decreased.