1
|
Ormsby MJ, Woodford L, Quilliam RS. Can plastic pollution drive the emergence and dissemination of novel zoonotic diseases? Environ Res 2024; 246:118172. [PMID: 38220083 DOI: 10.1016/j.envres.2024.118172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 01/16/2024]
Abstract
As the volume of plastic in the environment increases, so too does human interactions with plastic pollution. Similarly, domestic, feral, and wild animals are increasingly interacting with plastic pollution, highlighting the potential for contamination of plastic wastes with animal faeces, urine, saliva, and blood. Substantial evidence indicates that once in the environment, plastics rapidly become colonised by microbial biofilm (the so-called 'plastisphere), which often includes potentially harmful microbial pathogens (including pathogens that are zoonotic in nature). Climate change, increased urbanisation, and the intensification of agriculture, mean that the three-way interactions between humans, animals, and plastic pollution are becoming more frequent, which is significant as almost 60% of emerging human infectious diseases during the last century have been zoonotic. Here, we critically review the potential for contaminated environmental plastics to facilitate the evolution of novel pathogenic strains of microorganisms, and the subsequent role of plastic pollution in the cyclical dissemination of zoonotic pathogens. As the interactions between humans, animals, and plastic pollution continues to grow, and the volume of plastics entering the environment increases, there is clearly an urgent need to better understand the role of plastic waste in facilitating zoonotic pathogen evolution and dissemination, and the effect this can have on environmental and human health.
Collapse
Affiliation(s)
- Michael J Ormsby
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, UK.
| | - Luke Woodford
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, UK
| | - Richard S Quilliam
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, UK
| |
Collapse
|
2
|
Ormsby MJ, Woodford L, White HL, Fellows R, Oliver DM, Quilliam RS. Toxigenic Vibrio cholerae can cycle between environmental plastic waste and floodwater: Implications for environmental management of cholera. J Hazard Mater 2024; 461:132492. [PMID: 37717449 DOI: 10.1016/j.jhazmat.2023.132492] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/31/2023] [Accepted: 09/04/2023] [Indexed: 09/19/2023]
Abstract
Globally, there has been a significant rise in cholera cases and deaths, with an increase in the number of low- and middle-income countries (LMICs) reporting outbreaks. In parallel, plastic pollution in LMICs is increasing, and has become a major constituent of urban dump sites. The surfaces of environmental plastic pollution can provide a habitat for complex microbial biofilm communities; this so-called 'plastisphere' can also include human pathogens. Under conditions simulating a peri-urban environmental waste pile, we determine whether toxigenic Vibrio cholerae (O1 classical; O1 El Tor; O139) can colonise and persist on plastic following a simulated flooding event. Toxigenic V. cholerae colonized and persisted on plastic and organic waste for at least 14 days before subsequent transfer to either fresh or brackish floodwater, where they can further persist at concentrations sufficient to cause human infection. Taken together, this study suggests that plastics in the environment can act as significant reservoirs for V. cholerae, whilst subsequent transfer to floodwaters demonstrates the potential for the wider dissemination of cholera. Further understanding of how diseases interact with plastic waste will be central for combating infection, educating communities, and diminishing the public health risk of plastics in the environment.
Collapse
Affiliation(s)
- Michael J Ormsby
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA. UK.
| | - Luke Woodford
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA. UK
| | - Hannah L White
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA. UK
| | - Rosie Fellows
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA. UK
| | - David M Oliver
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA. UK
| | - Richard S Quilliam
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA. UK
| |
Collapse
|
3
|
Quilliam RS, Pow CJ, Shilla DJ, Mwesiga JJ, Shilla DA, Woodford L. Microplastics in agriculture - a potential novel mechanism for the delivery of human pathogens onto crops. Front Plant Sci 2023; 14:1152419. [PMID: 37636119 PMCID: PMC10448812 DOI: 10.3389/fpls.2023.1152419] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 07/20/2023] [Indexed: 08/29/2023]
Abstract
Mulching with plastic sheeting, the use of plastic carriers in seed coatings, and irrigation with wastewater or contaminated surface water have resulted in plastics, and microplastics, becoming ubiquitous in agricultural soils. Once in the environment, plastic surfaces quickly become colonised by microbial biofilm comprised of a diverse microbial community. This so-called 'plastisphere' community can also include human pathogens, particularly if the plastic has been exposed to faecal contamination (e.g., from wastewater or organic manures and livestock faeces). The plastisphere is hypothesised to facilitate the survival and dissemination of pathogens, and therefore plastics in agricultural systems could play a significant role in transferring human pathogens to crops, particularly as microplastics adhering to ready to eat crops are difficult to remove by washing. In this paper we critically discuss the pathways for human pathogens associated with microplastics to interact with crop leaves and roots, and the potential for the transfer, adherence, and uptake of human pathogens from the plastisphere to plants. Globally, the concentration of plastics in agricultural soils are increasing, therefore, quantifying the potential for the plastisphere to transfer human pathogens into the food chain needs to be treated as a priority.
Collapse
Affiliation(s)
- Richard S. Quilliam
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Chloe J. Pow
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| | - Dativa J. Shilla
- Department of Chemistry, Dar es Salaam University College of Education (DUCE), Dar es Salaam, Tanzania
| | - James J. Mwesiga
- Department of Aquatic Sciences and Fisheries Technology, University of Dar es Salaam, Dar es Salaam, Tanzania
| | - Daniel A. Shilla
- Department of Aquatic Sciences and Fisheries Technology, University of Dar es Salaam, Dar es Salaam, Tanzania
| | - Luke Woodford
- Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling, United Kingdom
| |
Collapse
|
4
|
Woodford L, Steketee PC, Evans DJ. Doomed drones? Using passage experiments and mathematical modelling to determine Deformed wing virus population dynamics in male honeybees. Proc Biol Sci 2023; 290:20231010. [PMID: 37339741 PMCID: PMC10281807 DOI: 10.1098/rspb.2023.1010] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 05/25/2023] [Indexed: 06/22/2023] Open
Abstract
Varroa destructor is an ectoparasitic mite of honeybees which vectors a range of pathogenic viruses, the most notable being Deformed wing virus (DWV). Mites parasitise bees during pupal development and male honeybees, drones, have a longer development cycle than female workers (24 versus 21 days), allow for more progeny mites to develop per foundress (1.6-2.5 compared to 0.7-1.45). How this longer exposure time influences evolution of the transmitted virus population is unknown. Using uniquely tagged viruses recovered from cDNA we investigated the replication, competition and morbidity of DWV genotypes in drones. Assays examining virus replication and morbidity revealed drones are highly susceptible to both predominant genotypes of DWV. In virus passage studies using an equimolar inocula of major DNA genotypes and their recombinants, the recombinant form dominated but did not reach 100% of the virus population within 10 passages. Using an in-silico model of the virus-mite-bee system we examined bottlenecks during virus acquisition by the mite and subsequent injection of viruses into the host, which may play a significant role in shaping virus diversity. This study furthers our understanding of the variables influencing DWV diversity changes and provides insight into areas of future research in the mite-virus-bee system.
Collapse
Affiliation(s)
- Luke Woodford
- Department of Biology, University of St. Andrews, Biomedical Sciences Research Complex, St. Andrews, None KY16 9ST, UK
| | - Pieter C. Steketee
- The Roslin Institute, Easter Bush Campus, Midlothian, Edinburgh, EH25 9RG, UK
| | - David J. Evans
- Department of Biology, University of St. Andrews, Biomedical Sciences Research Complex, St. Andrews, None KY16 9ST, UK
| |
Collapse
|
5
|
Woodford L, Sharpe G, Highet F, Evans DJ. All together now: Geographically coordinated miticide treatment benefits honey bee health. J Appl Ecol 2023; 60:790-802. [PMID: 38505246 PMCID: PMC10947427 DOI: 10.1111/1365-2664.14367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 12/20/2022] [Indexed: 01/21/2023]
Abstract
Deformed wing virus (DWV) is a pathogenic virus of honey bees transmitted by the ectoparasitic mite Varroa destructor. Annual overwintering colony losses, accounting for ~25% of all colonies, are associated with high levels of Varroa-DWV infestation. Effective miticide treatments are available to control Varroa. However, the absence of coordinated treatment means environmental transmission of mites continues unchecked. We aimed to determine whether rational, coordinated treatment is beneficial, and characterized the DWV population as an indicator of colony health.This study uses coordinated treatment of Varroa in a geographically isolated environment (Isle of Arran, Scotland) over 3 years. The study area contained 50-84 colonies managed by ~20 amateur beekeepers. Sampling and virus analysis to assess strain diversity and viral loads were conducted before and after treatments, and changes in population diversity were quantified by sequence analysis.Over the 3 years analysis of the virus population revealed that the dominant DWV variant shifted from Type A to Type B in all apiaries, regardless of mite levels or proximity to other colonies. During this period the number of managed colonies increased by 47% (57-84 colonies), but despite this, we estimate total mite numbers decreased by 58%. Synthesis and applications. In this study, the beekeepers in Arran significantly improved the number of colonies they managed, without importing any bees onto the island, indicating that an improved focus on management techniques, through the combination of a coordinated miticide programme and an improved understanding of bee diseases, could yield positive results for bee health and sustainability.
Collapse
Affiliation(s)
- Luke Woodford
- Biomedical Sciences Research ComplexUniversity of St. AndrewsSt. AndrewsUK
| | | | - Fiona Highet
- Science and Advice for Scottish AgricultureEdinburghUK
| | - David J. Evans
- Biomedical Sciences Research ComplexUniversity of St. AndrewsSt. AndrewsUK
| |
Collapse
|
6
|
Chandak P, Phillips BL, Bennett D, Uwechue R, Kessaris N, Shaw O, Maggs T, Woodford L, Veniard D, Perera R, Parmar K, Hunt BJ, Callaghan C, Dorling A, Mamode N. Modelling acute antibody-mediated rejection of human kidney transplants using ex-vivo warm machine perfusion. EBioMedicine 2022; 86:104365. [PMID: 36427468 PMCID: PMC9699940 DOI: 10.1016/j.ebiom.2022.104365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/27/2022] [Accepted: 10/27/2022] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Transplant rejection is a major cause of graft loss and morbidity. Currently, no human models of antibody-mediated rejection (AMR) exist, limiting mechanistic investigation and organ-specific targeted therapy. Here, using 12 human kidneys and ex-vivo normothermic machine perfusion, we demonstrate phenotypes of AMR after addition of antibodies against either human HLA class I or blood group antigens (A, B), thus modelling clinical AMR that can follow HLA incompatible (HLAi) or blood group incompatible (ABOi) transplantation. METHODS Discarded human kidneys with wide ranging demographics and cold ischaemia times (11-54 h) were perfused with red blood cells and fresh frozen plasma (FFP) as a source of complement/coagulation factors. For the HLAi model, 600 μg of W6/32 anti-class 1 HLA antibody was added to the circuit (time '0'). For the ABOi model, high titre FFP of the relevant blood group antibody was added. Renal blood flow index (RBFi, mL/min/100 g), C3 desArg, prothrombin fragments 1 + 2 and histology were determined. Our endpoints included haemodynamic changes, thrombosis, and biopsy proven complement deposition. FINDINGS Compared to control kidneys perfused without anti-donor antibodies, both models demonstrated haemodynamic collapse after antibody perfusion with only the HLAi model showing glomerular C4d deposition. INTERPRETATION We show that a clinically relevant human kidney model of AMR is feasible, and anticipate that these models, with refinements, could provide a basis to test different strategies to prevent AMR. FUNDING The Rosetrees and Stonygate Trust, The Royal College of Surgeons of England Fellowship Grant, NIHR Biomedical Research Centre/KCL Early Career Grant, Kidney Research U.K.
Collapse
Affiliation(s)
- Pankaj Chandak
- Transplant, Renal and Urology Directorate, Guy's and St Thomas' NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, United Kingdom; Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom.
| | - Benedict L Phillips
- Transplant, Renal and Urology Directorate, Guy's and St Thomas' NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, United Kingdom; Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Danothy Bennett
- Interface Analysis Centre, HH Wills Physics Laboratory, School of Physics, University of Bristol, Bristol, United Kingdom
| | - Raphael Uwechue
- Transplant, Renal and Urology Directorate, Guy's and St Thomas' NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, United Kingdom; Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Nicos Kessaris
- Transplant, Renal and Urology Directorate, Guy's and St Thomas' NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, United Kingdom; Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Olivia Shaw
- Synnovis, Clinical Transplantation Laboratory, Guy's and St Thomas' Hospitals, London, United Kingdom
| | - Tim Maggs
- Synnovis, Blood Transfusion Laboratory, Guy's and St Thomas' Hospitals, London, United Kingdom
| | - Luke Woodford
- Synnovis, Blood Transfusion Laboratory, Guy's and St Thomas' Hospitals, London, United Kingdom
| | - David Veniard
- Synnovis, Blood Transfusion Laboratory, Guy's and St Thomas' Hospitals, London, United Kingdom
| | - Ranmith Perera
- Department of Cellular Pathology, Guy's and St Thomas' NHS Foundation Trust, St Thomas' Hospital, London, United Kingdom
| | - Kiran Parmar
- Thrombosis and Vascular Biology Group, Rayne Institute, Guys and St Thomas' NHS Foundation Trust and King's Health Partners, St Thomas' Hospital, London, United Kingdom
| | - Beverley J Hunt
- Thrombosis and Vascular Biology Group, Rayne Institute, Guys and St Thomas' NHS Foundation Trust and King's Health Partners, St Thomas' Hospital, London, United Kingdom
| | - Chris Callaghan
- Transplant, Renal and Urology Directorate, Guy's and St Thomas' NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, United Kingdom; Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Anthony Dorling
- Transplant, Renal and Urology Directorate, Guy's and St Thomas' NHS Foundation Trust, Guy's Hospital, Great Maze Pond, London, United Kingdom; Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Nizam Mamode
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| |
Collapse
|
7
|
Woodford L, Christie CR, Campbell EM, Budge GE, Bowman AS, Evans DJ. Quantitative and Qualitative Changes in the Deformed Wing Virus Population in Honey Bees Associated with the Introduction or Removal of Varroa destructor. Viruses 2022; 14:v14081597. [PMID: 35893663 PMCID: PMC9332399 DOI: 10.3390/v14081597] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 07/08/2022] [Accepted: 07/19/2022] [Indexed: 02/06/2023] Open
Abstract
Varroa destructor is an ectoparasitic mite associated with significant losses of honeybee colonies globally. The mite vectors a range of pathogenic viruses, the most important of which is the Deformed wing virus (DWV). In the absence of Varroa, DWV exists as a low-level, highly diverse virus population. However, when transmitted by Varroa, certain variants become highly elevated, and may become near-clonal and cause symptomatic infections. Mite transmission between colonies can occur when parasitised workers drift from or rob adjacent hives. These activities can result in elevated mite levels, but the resulting change in the DWV population, the primary determinant of winter colony losses, has not been determined. In reciprocal studies, we investigated the influence of the removal of mites, or their acquisition, on the DWV population. When mites were removed from heavily infested colonies, there was a striking and rapid reduction in virus load. Conversely, siting Varroa-naïve colonies in a mite-infested apiary resulted in the acquisition of mites and concomitant changes in the virus population. We observed both near-clonal and highly divergent virus populations regardless of titre, suggesting changes were stochastic and colony-specific. Our findings have implications for the outcome of strategies in areas with total or patchy implementation of Varroa control plans.
Collapse
Affiliation(s)
- Luke Woodford
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews KY16 9ST, UK;
- Correspondence:
| | - Craig R. Christie
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK; (C.R.C.); (E.M.C.); (A.S.B.)
| | - Ewan M. Campbell
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK; (C.R.C.); (E.M.C.); (A.S.B.)
| | - Giles E. Budge
- School of Natural and Environmental Sciences, Newcastle University, Newcastle NE1 7RU, UK;
| | - Alan S. Bowman
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK; (C.R.C.); (E.M.C.); (A.S.B.)
| | - David J. Evans
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews KY16 9ST, UK;
| |
Collapse
|
8
|
Gusachenko ON, Woodford L, Balbirnie-Cumming K, Evans DJ. First come, first served: superinfection exclusion in Deformed wing virus is dependent upon sequence identity and not the order of virus acquisition. ISME J 2021; 15:3704-3713. [PMID: 34193965 PMCID: PMC8630095 DOI: 10.1038/s41396-021-01043-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 02/06/2023]
Abstract
Deformed wing virus (DWV) is the most important globally distributed pathogen of honey bees and, when vectored by the ectoparasite Varroa destructor, is associated with high levels of colony losses. Divergent DWV types may differ in their pathogenicity and are reported to exhibit superinfection exclusion upon sequential infections, an inevitability in a Varroa-infested colony. We used a reverse genetic approach to investigate competition and interactions between genetically distinct or related virus strains, analysing viral load over time, tissue distribution with reporter gene-expressing viruses and recombination between virus variants. Transient competition occurred irrespective of the order of virus acquisition, indicating no directionality or dominance. Over longer periods, the ability to compete with a pre-existing infection correlated with the genetic divergence of the inoculae. Genetic recombination was observed throughout the DWV genome with recombinants accounting for ~2% of the population as determined by deep sequencing. We propose that superinfection exclusion, if it occurs at all, is a consequence of a cross-reactive RNAi response to the viruses involved, explaining the lack of dominance of one virus type over another. A better understanding of the consequences of dual- and superinfection will inform development of cross-protective honey bee vaccines and landscape-scale DWV transmission and evolution.
Collapse
Affiliation(s)
- Olesya N. Gusachenko
- grid.11914.3c0000 0001 0721 1626Biomedical Sciences Research Complex, University of St. Andrews, North Haugh, St. Andrews, UK
| | - Luke Woodford
- grid.11914.3c0000 0001 0721 1626Biomedical Sciences Research Complex, University of St. Andrews, North Haugh, St. Andrews, UK
| | - Katharin Balbirnie-Cumming
- grid.11914.3c0000 0001 0721 1626Biomedical Sciences Research Complex, University of St. Andrews, North Haugh, St. Andrews, UK
| | - David J. Evans
- grid.11914.3c0000 0001 0721 1626Biomedical Sciences Research Complex, University of St. Andrews, North Haugh, St. Andrews, UK
| |
Collapse
|
9
|
Woodford L, Evans DJ. Deformed wing virus: using reverse genetics to tackle unanswered questions about the most important viral pathogen of honey bees. FEMS Microbiol Rev 2020; 45:6035241. [PMID: 33320949 DOI: 10.1093/femsre/fuaa070] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 12/11/2020] [Indexed: 12/31/2022] Open
Abstract
Deformed wing virus (DWV) is the most important viral pathogen of honey bees. It usually causes asymptomatic infections but, when vectored by the ectoparasitic mite Varroa destructor, it is responsible for the majority of overwintering colony losses globally. Although DWV was discovered four decades ago, research has been hampered by the absence of an in vitro cell culture system or the ability to culture pure stocks of the virus. The recent developments of reverse genetic systems for DWV go some way to addressing these limitations. They will allow the investigation of specific questions about strain variation, host tropism and pathogenesis to be answered, and are already being exploited to study tissue tropism and replication in Varroa and non-Apis pollinators. Three areas neatly illustrate the advances possible with reverse genetic approaches: (i) strain variation and recombination, in which reverse genetics has highlighted similarities rather than differences between virus strains; (ii) analysis of replication kinetics in both honey bees and Varroa, in studies that likely explain the near clonality of virus populations often reported; and (iii) pathogen spillover to non-Apis pollinators, using genetically tagged viruses to accurately monitor replication and infection.
Collapse
Affiliation(s)
- Luke Woodford
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews, KY16 9ST, UK
| | - David J Evans
- Biomedical Sciences Research Complex, University of St Andrews, St Andrews, KY16 9ST, UK
| |
Collapse
|
10
|
Woodford L, Evans D, Highet F, Bowman A. Healthy Honey Bees – analysis of the Deformed Wing Virus population to assess rational Varroa control on a Scottish island. Access Microbiol 2020. [DOI: 10.1099/acmi.ac2020.po0329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Varroa destructor is an ectoparasitic mite associated with significant losses of honey bee colonies globally. The mite vectors a range of pathogenic viruses, most important of which is Deformed Wing Virus (DWV, (+)ssRNA). Overwintering colony losses, accounting for the death of ∼25% of all colonies each year, are associated with high levels of Varroa-DWV infestation. Effective miticide treatments are available to control Varroa. However, the absence of coordinated treatment means environmental transmission of mites continued unchecked. We aim to determine whether rational, coordinated treatment is beneficial, using features of the DWV population as an indicator of colony health. This study uses coordinated treatment of Varroa in a geographically isolated environment (Isle of Arran, Scotland). It is reported that a high level of a near-clonal virus population is associated with Varroa infestation and colony losses, whereas Varroa-free healthy colonies carry only low levels of a diverse population of DWV. The study area contains 50-85 colonies and 25 beekeepers. Sampling and virus analysis – strain diversity and viral loads – have been conducted before and after treatment. Changes in virus diversity are quantified by next generation sequencing analysis to determine population diversity. In the first two years we have observed a geographic decrease in Varroa and changes in the composition of the virus population. This study will inform our development of rational Varroa control strategies for beekeepers in temperate regions and could be used to inform policy changes regarding treatment regimes in Scotland and elsewhere for this global pathogen.
Collapse
Affiliation(s)
| | - David Evans
- University of St Andrews,St Andrews,United Kingdom
| | | | - Alan Bowman
- University of Aberdeen,Aberdeen,United Kingdom
| |
Collapse
|
11
|
Gusachenko ON, Woodford L, Balbirnie-Cumming K, Campbell EM, Christie CR, Bowman AS, Evans DJ. Green Bees: Reverse Genetic Analysis of Deformed Wing Virus Transmission, Replication, and Tropism. Viruses 2020; 12:E532. [PMID: 32408550 PMCID: PMC7291132 DOI: 10.3390/v12050532] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/06/2020] [Accepted: 05/08/2020] [Indexed: 01/04/2023] Open
Abstract
Environmental and agricultural pollination services by honey bees, Apis mellifera, and honey production are compromised by high levels of annual colony losses globally. The majority are associated with disease caused by deformed wing virus (DWV), a positive-strand RNA virus, exacerbated by the ectoparasitic mite Varroa destructor. To improve honey bee health, a better understanding of virus transmission and pathogenesis is needed which requires the development of tools to study virus replication, transmission, and localisation. We report the use of reverse genetic (RG) systems for the predominant genetically distinct variants of DWV to address these questions. All RG-recovered viruses replicate within 24 h post-inoculation of pupae and could recapitulate the characteristic symptoms of DWV disease upon eclosion. Larvae were significantly less susceptible but could be infected orally and subsequently developed disease. Using genetically tagged RG DWV and an in vitro Varroa feeding system, we demonstrate virus replication in the mite by accumulation of tagged negative-strand viral replication intermediates. We additionally apply a modified DWV genome expressing a fluorescent reporter protein for direct in vivo observation of virus distribution in injected pupae or fed larvae. Using this, we demonstrate extensive sites of virus replication in a range of pupal tissues and organs and in the nascent wing buds in larvae fed high levels of virus, indicative of a direct association between virus replication and pathogenesis. These studies provide insights into virus replication kinetics, tropism, transmission, and pathogenesis, and produce new tools to help develop the understanding needed to control DWV-mediated colony losses.
Collapse
Affiliation(s)
- Olesya N. Gusachenko
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews KY16 9ST, UK; (L.W.); (D.J.E.)
| | - Luke Woodford
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews KY16 9ST, UK; (L.W.); (D.J.E.)
| | - Katharin Balbirnie-Cumming
- Centre for Inflammation Research, Queen‘s Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK;
| | - Ewan M. Campbell
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK; (E.M.C.); (C.R.C.); (A.S.B.)
| | - Craig R. Christie
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK; (E.M.C.); (C.R.C.); (A.S.B.)
| | - Alan S. Bowman
- Institute of Biological and Environmental Sciences, School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK; (E.M.C.); (C.R.C.); (A.S.B.)
| | - David J. Evans
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews KY16 9ST, UK; (L.W.); (D.J.E.)
| |
Collapse
|
12
|
Forsyth DM, Pople A, Woodford L, Brennan M, Amos M, Moloney PD, Fanson B, Story G. Landscape-scale effects of homesteads, water, and dingoes on invading chital deer in Australia’s dry tropics. J Mammal 2019. [DOI: 10.1093/jmammal/gyz139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Identifying landscape features and processes that facilitate the persistence of populations is particularly important for invasive mammal species, because it can focus management interventions on relatively small areas. We used camera traps to test predictions concerning the relative abundance of invading chital deer (Axis axis) on seven cattle ranches in northern Australia: that abundance of chital deer would be highest near permanent water and near homesteads, and that dingoes (Canis dingo) reduce abundance of chital deer. Distance from the nearest homestead determined deer abundance (as indexed by images per camera-day), with negligible abundance > 4 km from homesteads. In contrast, distance from homestead did not predict abundance of feral pigs (Sus scrofa), macropods, or dingoes. Abundance of chital deer also declined with increasing distance from water, as did feral pig abundance. There was no relationship between either macropod or dingo abundance and distance to water. The abundance of chital deer was unaffected by dingo abundance, but 75–100% of dingo scats collected within 1 km of homesteads contained chital deer. The high abundances of chital deer near homesteads are likely due to increased food quality or quantity, or protection from dingoes, but these hypotheses require further testing. We conclude that homesteads and permanent water are important determinants of the distribution and abundance of invasive chital deer in northern Australia (i.e., they are “invasion hubs” for this species). Our results suggest that, during the dry season, managers should survey for and attempt to control chital deer within 4 km of homesteads and within 3 km of water.
Collapse
Affiliation(s)
- David M Forsyth
- Vertebrate Pest Research Unit, NSW Department of Primary Industries, Orange, New South Wales, Australia
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Anthony Pople
- Biosecurity Queensland, Department of Agriculture and Fisheries, Brisbane, Queensland, Australia
| | - Luke Woodford
- Biosecurity Queensland, Department of Agriculture and Fisheries, Brisbane, Queensland, Australia
- Arthur Rylah Institute for Environmental Research, Department of Environment, Land, Water and Planning, Heidelberg, Victoria, Australia
| | - Michael Brennan
- Biosecurity Queensland, Department of Agriculture and Fisheries, Brisbane, Queensland, Australia
| | - Matt Amos
- Biosecurity Queensland, Department of Agriculture and Fisheries, Brisbane, Queensland, Australia
| | - Paul D Moloney
- Arthur Rylah Institute for Environmental Research, Department of Environment, Land, Water and Planning, Heidelberg, Victoria, Australia
| | - Ben Fanson
- Arthur Rylah Institute for Environmental Research, Department of Environment, Land, Water and Planning, Heidelberg, Victoria, Australia
| | - Georgeanna Story
- Scats About Ecological, Majors Creek, New South Wales, Australia
| |
Collapse
|
13
|
Woodford L, Bianco G, Ivanova Y, Dale M, Elmer K, Rae F, Larcombe SD, Helm B, Ferguson HM, Baldini F. Vector species-specific association between natural Wolbachia infections and avian malaria in black fly populations. Sci Rep 2018; 8:4188. [PMID: 29520067 PMCID: PMC5843599 DOI: 10.1038/s41598-018-22550-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 02/21/2018] [Indexed: 11/08/2022] Open
Abstract
Artificial infection of mosquitoes with the endosymbiont bacteria Wolbachia can interfere with malaria parasite development. Therefore, the release of Wolbachia-infected mosquitoes has been proposed as a malaria control strategy. However, Wolbachia effects on vector competence are only partly understood, as indicated by inconsistent effects on malaria infection reported under laboratory conditions. Studies of naturally-occurring Wolbachia infections in wild vector populations could be useful to identify the ecological and evolutionary conditions under which these endosymbionts can block malaria transmission. Here we demonstrate the occurrence of natural Wolbachia infections in three species of black fly (genus Simulium), which is a main vector of the avian malaria parasite Leucocytozoon. Prevalence of Leucocytozoon was high (25%), but the nature and magnitude of its association with Wolbachia differed between black fly species. Wolbachia infection was positively associated with avian malaria infection in S. cryophilum, negatively associated in S. aureum, and unrelated in S. vernum. These differences suggest that Wolbachia interacts with the parasite in a vector host species-specific manner. This provides a useful model system for further study of how Wolbachia influences vector competence. Such knowledge, including the possibility of undesirable positive association, is required to guide endosymbiont based control methods.
Collapse
Affiliation(s)
- Luke Woodford
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
- Department of Biomolecular Sciences, School of Biology, University of St Andrews, St Andrews, United Kingdom
| | - Giovanni Bianco
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Yoana Ivanova
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Maeve Dale
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Kathryn Elmer
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Fiona Rae
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Stephen D Larcombe
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Barbara Helm
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Heather M Ferguson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Francesco Baldini
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom.
| |
Collapse
|
14
|
Capilla-Lasheras P, Dominoni DM, Babayan SA, O'Shaughnessy PJ, Mladenova M, Woodford L, Pollock CJ, Barr T, Baldini F, Helm B. Elevated Immune Gene Expression Is Associated with Poor Reproductive Success of Urban Blue Tits. Front Ecol Evol 2017. [DOI: 10.3389/fevo.2017.00064] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
|
15
|
Forsyth DM, Woodford L, Moloney PD, Hampton JO, Woolnough AP, Tucker M. How does a carnivore guild utilise a substantial but unpredictable anthropogenic food source? Scavenging on hunter-shot ungulate carcasses by wild dogs/dingoes, red foxes and feral cats in south-eastern Australia revealed by camera traps. PLoS One 2014; 9:e97937. [PMID: 24918425 PMCID: PMC4053338 DOI: 10.1371/journal.pone.0097937] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 04/27/2014] [Indexed: 11/19/2022] Open
Abstract
There is much interest in understanding how anthropogenic food resources subsidise carnivore populations. Carcasses of hunter-shot ungulates are a potentially substantial food source for mammalian carnivores. The sambar deer (Rusa unicolor) is a large (≥150 kg) exotic ungulate that can be hunted throughout the year in south-eastern Australia, and hunters are not required to remove or bury carcasses. We investigated how wild dogs/dingoes and their hybrids (Canis lupus familiaris/dingo), red foxes (Vulpes vulpes) and feral cats (Felis catus) utilised sambar deer carcasses during the peak hunting seasons (i.e. winter and spring). We placed carcasses at 1-km intervals along each of six transects that extended 4-km into forest from farm boundaries. Visits to carcasses were monitored using camera traps, and the rate of change in edible biomass estimated at ∼14-day intervals. Wild dogs and foxes fed on 70% and 60% of 30 carcasses, respectively, but feral cats seldom (10%) fed on carcasses. Spatial and temporal patterns of visits to carcasses were consistent with the hypothesis that foxes avoid wild dogs. Wild dog activity peaked at carcasses 2 and 3 km from farms, a likely legacy of wild dog control, whereas fox activity peaked at carcasses 0 and 4 km from farms. Wild dog activity peaked at dawn and dusk, whereas nearly all fox activity occurred after dusk and before dawn. Neither wild dogs nor foxes remained at carcasses for long periods and the amount of feeding activity by either species was a less important predictor of the loss of edible biomass than season. Reasons for the low impacts of wild dogs and foxes on sambar deer carcass biomass include the spatially and temporally unpredictable distribution of carcasses in the landscape, the rapid rate of edible biomass decomposition in warm periods, low wild dog densities and the availability of alternative food resources.
Collapse
Affiliation(s)
- David M. Forsyth
- Arthur Rylah Institute for Environmental Research, Department of Environment and Primary Industries, Heidelberg, Victoria, Australia
- * E-mail:
| | - Luke Woodford
- Arthur Rylah Institute for Environmental Research, Department of Environment and Primary Industries, Heidelberg, Victoria, Australia
| | - Paul D. Moloney
- Arthur Rylah Institute for Environmental Research, Department of Environment and Primary Industries, Heidelberg, Victoria, Australia
| | - Jordan O. Hampton
- Ecotone Wildlife Veterinary Services, Canberra, Australian Capital Territory, Australia
| | - Andrew P. Woolnough
- Invasive Plants and Animals Branch, Biosecurity Division, Department of Environment and Primary Industries, Melbourne, Victoria, Australia
| | - Mark Tucker
- Melbourne Water, Reefton, Victoria, Australia
| |
Collapse
|
16
|
Forsyth DM, Gormley AM, Woodford L, Fitzgerald T. Effects of large-scale high-severity fire on occupancy and abundances of an invasive large mammal in south-eastern Australia. Wildl Res 2012. [DOI: 10.1071/wr12033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context
Despite large mammals being an important component of many ecosystems, there is little information on the impacts of fire on large mammal populations.
Aims
We evaluated the effects of the large-scale high-severity ‘Black Saturday’ fires of 7 February 2009 on occupancy and abundances of an invasive large mammal, the sambar deer (Cervus unicolor), in south-eastern Australia.
Methods
The effects of the Black Saturday fires on the abundance of sambar deer were assessed using repeated annual counts of faecal pellets during 2007–11 in Kinglake National Park, which was burnt, and in Mount Buffalo National Park, which was not burnt. Pre-fire occupancy was modelled from data collected at 80 4-km2 cells using three survey methods. The same survey methods were used at 15 burnt (n = 9 sampled pre-fire) and 15 unburnt (n = 5 sampled pre-fire) cells 16–24 months after Black Saturday. Because multiple surveys were performed in each cell, we used a Bayesian state–space site-occupancy model to partition changes in the probability of occupancy from changes in the probability of detection.
Key results
Counts of sambar deer pellets increased linearly during 2007–11 in the unburnt Mount Buffalo National Park. Pellet counts also increased linearly in Kinglake National Park from 2007 to 2008, and then decreased (to zero) following Black Saturday; pellet counts increased again in 2010 and 2011. Sambar deer occupancy was weakly reduced (from 0.99 to 0.88) in burnt cells 16–24 months after Black Saturday, but was little changed in unburnt cells (from 0.99 to 0.98).
Conclusions
We conclude that the abundance of sambar deer was substantially reduced by the large-scale high-severity Black Saturday fires, but that most burnt habitat was reoccupied 16–24 months later.
Implications
There is concern about the negative impacts of invasive sambar deer on native biodiversity, particularly immediately post-fire. Our study suggests that it takes at least 8 months before sambar deer recolonise areas burnt by a large-scale high-severity fire; however, a risk-averse approach would be to act (e.g. by erecting fences or culling) sooner than that.
Collapse
|
17
|
Gormley AM, Forsyth DM, Griffioen P, Lindeman M, Ramsey DSL, Scroggie MP, Woodford L. Using presence-only and presence-absence data to estimate the current and potential distributions of established invasive species. J Appl Ecol 2010; 48:25-34. [PMID: 21339812 PMCID: PMC3038347 DOI: 10.1111/j.1365-2664.2010.01911.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 11/02/2010] [Indexed: 12/03/2022]
Abstract
1.Predicting the current and potential distributions of established invasive species is critical for evaluating management options, but methods for differentiating these distributions have received little attention. In particular, there is uncertainty among invasive species managers about the value of information from incidental sightings compared to data from designed field surveys. This study compares the two approaches, and develops a unifying framework, using the case of invasive sambar deer Cervus unicolor in Victoria, Australia. 2.We first used 391 incidental sightings of sambar deer and 12 biophysical variables to construct a presence-only habitat suitability model using Maxent. We then used that model to stratify field sampling, with proportionately greater sampling of cells with high predicted habitat suitability. Field sampling, consisting of faecal pellet surveys, sign surveys and camera trapping, was conducted in 80 4-km2 grid cells. A Bayesian state-space occupancy model was used to predict probability of suitable habitat from the field data. 3.The Maxent and occupancy models predicted similar spatial distributions of habitat suitability for sambar deer in Victoria and there was a strong positive correlation between the rankings of cells by the two approaches. The congruence of the two models suggests that any spatial and detection biases in the presence-only data were relatively unimportant in our study. 4.We predicted the extent of suitable habitat from the occupancy model using a threshold that gave a false negative error rate of 0·05. The current distribution was the suitable habitat within a kernel that had a 99·5% chance of including the presence locations pooled from incidental sightings and field surveys: the potential distribution was suitable habitat outside that kernel. Several discrete areas of potential distribution were identified as priorities for surveillance monitoring with the aim of detecting and managing incursions of sambar deer. 5.Synthesis and applications.Our framework enables managers to robustly estimate the current and potential distributions of established invasive species using either presence-only and/or presence–absence data. Managers can then focus control and/or containment actions within the current distribution and establish surveillance monitoring to detect incursions within the potential distribution.
Collapse
Affiliation(s)
- Andrew M Gormley
- Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment123 Brown Street, Heidelberg 3084, Australia
| | - David M Forsyth
- Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment123 Brown Street, Heidelberg 3084, Australia
- *Correspondence author. E-mail:
| | - Peter Griffioen
- Peter Griffioen Consulting3/391 Upper Heidelberg Road, Ivanhoe 3079, Australia
| | - Michael Lindeman
- Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment123 Brown Street, Heidelberg 3084, Australia
| | - David SL Ramsey
- Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment123 Brown Street, Heidelberg 3084, Australia
| | - Michael P Scroggie
- Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment123 Brown Street, Heidelberg 3084, Australia
| | - Luke Woodford
- Arthur Rylah Institute for Environmental Research, Department of Sustainability and Environment123 Brown Street, Heidelberg 3084, Australia
| |
Collapse
|
18
|
Nachshen JS, Woodford L, Minnes P. The Family Stress and Coping Interview for families of individuals with developmental disabilities: a lifespan perspective on family adjustment. J Intellect Disabil Res 2003; 47:285-290. [PMID: 12787160 DOI: 10.1046/j.1365-2788.2003.00490.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
BACKGROUND The present study investigated the psychometric properties of the Family Stress and Coping Interview (FSCI), a questionnaire designed to quantitatively and qualitatively examine the experiences of parents of children with developmental disabilities (DDs). METHODS The participants consisted of 106 primary caregivers of 106 individuals with DDs from centres in Eastern, Central and North-western Ontario, Canada. The participants completed a demographic questionnaire, the FSCI, and the Vineland Adaptive Behaviour Scales. RESULTS The results of this study indicate that the FSCI has adequate reliability (i.e. internal consistency and long-term stability) and validity (i.e. independent item ratings and discriminant validity). CONCLUSIONS The results of this study support the use of the FSCI as a measure of family stress in research and practice.
Collapse
Affiliation(s)
- J S Nachshen
- Department of Psychology, Queen's University, Kingston, Ontario, Canada
| | | | | |
Collapse
|