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Wood, C. L.

Publications and source records attributed to Wood, C. L..

5 recordsLinked to original sources

A baseline for aquatic parasite diversity in West African mangroves: host-parasite records, DNA barcodes, and an experimental design for future use

Macroparasites represent a major fraction of biodiversity and biomass in marine ecosystems, yet remain substantially underrepresented in ecological surveys and food-web models, particularly in the Global South. This study addresses this geographic bias by providing the first comprehensive ecological survey of macroparasite communities of fishes in a West African Marine Protected Area (MPA) and adjacent Open-Access Area (OAA) characterised by mangrove forests. We collected 5,020 parasite specimens from 10 fish and one crab species in the Saloum Delta, Senegal, identifying 27 parasite species across all major taxa. Our findings include 15 new records for Senegal of which 11 are also new for West Africa. Additionally, 64% of host-parasite combinations constitute new host records. We provide 208 DNA barcodes, offering the first molecular data for 31% of these species globally and establishing a reference library for future DNA metabarcoding efforts in the region. Using sample size-corrected biodiversity indices and mixed-model analyses, we detected significant variations in parasite infracommunities and component communities between the MPA and OAA, demonstrating the feasibility of using comparative study designs to monitor fisheries impacts on parasite diversity in the Saloum Delta. Furthermore, the identification of trophically transmitted parasites provided evidence of unstudied food-web connections, e.g. predator-prey linkages between fishes and higher-trophic-level definitive hosts including birds and elasmobranchs. By integrating morphological identification, molecular data, and archiving of voucher specimens into publicly accessible, curated collections, this study establishes a new baseline for marine parasite biodiversity in West Africa and provides a methodological blueprint for surveying understudied regions.

zoology↗

Detection of Echinococcus multilocularis in coyotes in Washington State, USA highlights need for increased global wildlife surveillance

Echinococcus multilocularis is a zoonotic cestode that uses canids as definitive hosts and rodents as intermediate hosts. In humans, this parasite is the causative agent of alveolar echinococcosis. Recently, its range has been expanding across the Northern Hemisphere, and it is increasingly detected in wild canids, domestic dogs, and humans across Canada and the United States. While this expansion has been documented in isolated studies across the continent, a lack of routine sampling in wildlife hinders our ability to anticipate and mitigate further spread of E. multilocularis. We confirmed the presence of E. multilocularis in Washington State, USA, using a combination of morphological and molecular techniques across carcasses and field-collected scats of coyotes (Canis latrans), this regions most common wild canid. Morphological identification of adult worms was confirmed by next-generation sequencing. Over a third of all samples tested positive for E. multilocularis when all methodologies were combined. Sequencing revealed a haplotype of E. multilocularis matching a documented haplotype originally of European origin in British Columbia, Canada. Our study provides the first confirmation of E. multilocularis in a wild host on the west coast of the U.S and provides additional haplotype information crucial to tracking the geographical expansion of the parasite. We also provide a new next-generation sequencing primer targeting cestodes of canids. The difference in amplification between intestinal and fecal samples suggests that non-invasive fecal sampling using DNA metabarcoding--a popular method of helminth surveillance --may lead to underestimation of prevalence, hindering control measures. The global significance of these findings extends beyond North America; E. multilocularis is a major public health concern in Europe and Asia, where alveolar echinococcosis is increasingly diagnosed in humans. Our study highlights the urgent need for increased surveillance and improved diagnostic strategies worldwide, particularly in regions with significant human-wildlife contact. Author summaryParasites that are transmitted between wildlife, domestic animals, and people are an important part of global health. One such parasite is Echinococcus multilocularis, a small tapeworm of canids that can cause a severe, life-threatening disease in humans called alveolar echinococcosis. Many wild canid hosts of the parasite, such as coyotes, overlap significantly with domestic dogs, which facilitates transmission to humans. In Europe, Asia, and Arctic regions of North America, E. multilocularis has long been recognized as a major public health problem. In recent decades its range has expanded across the Northern Hemisphere, raising concern. In this study, we discovered E. multilocularis in coyotes in a densely populated area of Washington State, USA -- the first detection of E. multilocularis in a wild host in the region. More than one-third of our coyote samples contained E. multilocularis, confirming that it is widespread in the area. Genetic testing showed that the strain we detected matched one previously found in Canada, originally from Europe. Our findings underscore the importance of monitoring E. multilocularis and other parasites in wildlife so that emerging public health threats can be detected early, reducing risk to people and pets.

ecology↗

Widespread parasite infections in living resident killer whales in the Northeast Pacific Ocean

Multiple populations of resident ecotype killer whales (Orcinus orca ater) inhabit the Northeast Pacific, but the southern resident killer whale (SRKW) population is the most at-risk. SRKWs were listed as endangered in the United States in 2005 and have since shown little sign of recovery. Several factors have been identified as key threats to this population, and previously published studies suggest the population may be energetically stressed. Underlying health risks, such as parasitism, may be contributing to this populations failure to recover, but little is known about parasite infections in living individuals from natural killer whale populations. To assess the prevalence of internal parasite infections in Northeastern Pacific killer whales, we examined scat from endangered SRKW (n = 25) compared to two conspecific populations of resident killer whales that are not in decline: northern resident (NRKW, n = 2) and southern Alaska resident killer whales (SARKW, n = 7), and one offshore killer whale (OKW, n = 1). We analyzed 35 fecal samples collected from 27 wild killer whales using both microscopic identification of parasite eggs and genetic detection of parasites through DNA metabarcoding. We used body condition indices derived from concurrent aerial photogrammetry to evaluate whether parasite infection status was associated with individual body condition. We found that most individuals sampled (94%) were positive for Anisakis spp. - a parasitic nematode known to inhabit the intestines of cetaceans. These infections were detected across populations, and were not correlated with body condition, based on limited paired data. These results suggest that Anisakis infection is widespread among resident killer whales of the Northeast Pacific. The widespread detections of Anisakis among the samples examined here emphasizes the need for further work to understand the potential health impacts of parasitic infections on individual killer whales, and potential synergistic effects with other environmental stressors.

ecology↗

Cell extrusion - a novel mechanism driving neural crest cell delamination

Neural crest cells (NCC) comprise a heterogeneous population of cells with variable potency, that contribute to nearly every tissue and organ system throughout the body. Considered unique to vertebrates, NCC are transiently generated within the dorsolateral region of the neural plate or neural tube, during neurulation. Their delamination and migration are crucial events in embryo development as the differentiation of NCC is heavily influenced by their final resting locations. Previous work in avian and aquatic species has shown that NCC delaminate via an epithelial-mesenchymal transition (EMT), which transforms these stem and progenitor cells from static polarized epithelial cells into migratory mesenchymal cells with fluid front and back polarity. However, the cellular and molecular drivers facilitating NCC delamination in mammals are poorly understood. We performed live timelapse imaging of NCC delamination in mouse embryos and discovered a group of cells that exit the neuroepithelium as isolated round cells, which then halt for a short period prior to acquiring the mesenchymal migratory morphology classically associated with most delaminating NCC. High magnification imaging and protein localization analyses of the cytoskeleton, together with measurements of pressure and tension of delaminating NCC and neighboring neuroepithelial cells, revealed these round NCC are extruded from the neuroepithelium prior to completion of EMT. Furthermore, we demonstrate that cranial NCC are extruded through activation of the mechanosensitive ion channel, PIEZO1, a key regulator of the live cell extrusion pathway, revealing a new role for PIEZO1 in neural crest cell development. Our results elucidating the cellular and molecular dynamics orchestrating NCC delamination support a model in which high pressure and tension in the neuroepithelium results in activation of the live cell extrusion pathway and delamination of a subpopulation of NCC in parallel with EMT. This model has broad implications for our understanding of cell delamination in development and disease.

developmental biology↗

Prawn aquaculture as a method for schistosomiasis control and poverty alleviation: a win-win approach to address a critical infectious disease of poverty

Recent evidence suggests crustacean snail predators may aid schistosomiasis control programs by targeting the environmental component of the parasites life cycle through predation of the snail species that serve as intermediate hosts of the parasite. We evaluate costs, benefits, and potential synergies between schistosomiasis control and aquaculture of giant prawns using an integrated bio-economic-epidemiologic model. We identified combinations of stocking density and aquaculture cycle length that maximize profit and offer disease control benefits for sustainable schistosomiasis control. We consider two prawn species in sub-Saharan Africa: the endemic, non-domesticated Macrobrachium vollenhovenii, and the non-native, domesticated Macrobrachium rosenbergii. We find that, at profit-optimal densities, both M. rosenbergii and M. vollenhovenii can complement conventional control approaches (mass drug treatment of people) and lead to sustainable schistosomiasis control. We conclude that integrated aquaculture strategies can be a win-win strategy in terms of health and sustainable development in schistosomiasis endemic regions of the world.

epidemiology↗