Surveillance strategies for Classical Swine Fever in wild boar – a comprehensive evaluation study to ensure powerful surveillance

Surveillance of Classical Swine Fever (CSF) should not only focus on livestock, but must also include wild boar. To prevent disease transmission into commercial pig herds, it is therefore vital to have knowledge about the disease status in wild boar. In the present study, we performed a comprehensive evaluation of alternative surveillance strategies for Classical Swine Fever (CSF) in wild boar and compared them with the currently implemented conventional approach. The evaluation protocol was designed using the EVA tool, a decision support tool to help in the development of an economic and epidemiological evaluation protocol for surveillance. To evaluate the effectiveness of the surveillance strategies, we investigated their sensitivity and timeliness. Acceptability was analysed and finally, the cost-effectiveness of the surveillance strategies was determined. We developed 69 surveillance strategies for comparative evaluation between the existing approach and the novel proposed strategies. Sampling only within sub-adults resulted in a better acceptability and timeliness than the currently implemented strategy. Strategies that were completely based on passive surveillance performance did not achieve the desired detection probability of 95%. In conclusion, the results of the study suggest that risk-based approaches can be an option to design more effective CSF surveillance strategies in wild boar

Biosecurity and Vector Behaviour: Evaluating the Potential Threat Posed by Anglers and Canoeists as Pathways for the Spread of Invasive Non-Native Species and Pathogens

Invasive non-native species (INNS) endanger native biodiversity and are a major economic problem. The management of pathways to prevent their introduction and establishment is a key target in the Convention on Biological Diversity's Aichi biodiversity targets for 2020. Freshwater environments are particularly susceptible to invasions as they are exposed to multiple introduction pathways, including non-native fish stocking and the release of boat ballast water. Since many freshwater INNS and aquatic pathogens can survive for several days in damp environments, there is potential for transport between water catchments on the equipment used by recreational anglers and canoeists. To quantify this biosecurity risk, we conducted an online questionnaire with 960 anglers and 599 canoeists to investigate their locations of activity, equipment used, and how frequently equipment was cleaned and/or dried after use. Anglers were also asked about their use and disposal of live bait. Our results indicate that 64% of anglers and 78.5% of canoeists use their equipment/boat in more than one catchment within a fortnight, the survival time of many of the INNS and pathogens considered in this study and that 12% of anglers and 50% of canoeists do so without either cleaning or drying their kit between uses. Furthermore, 8% of anglers and 28% of canoeists had used their equipment overseas without cleaning or drying it after each use which could facilitate both the introduction and secondary spread of INNS in the UK. Our results provide a baseline against which to evaluate the effectiveness of future biosecurity awareness campaigns, and identify groups to target with biosecurity awareness information. Our results also indicate that the biosecurity practices of these groups must improve to reduce the likelihood of inadvertently spreading INNS and pathogens through these activities

Differential characterization of emerging skin diseases of rainbow trout - a standardized approach to capturing disease characteristics and development of case definitions

Farmed and wild salmonids are affected by a variety of skin conditions, some of which have significant economic and welfare implications. In many cases, the causes are not well understood, and one example is cold water strawberry disease of rainbow trout, also called red mark syndrome, which has been recorded in the UK since 2003. To date, there are no internationally agreed methods for describing these conditions, which has caused confusion for farmers and health professionals, who are often unclear as to whether they are dealing with a new or a previously described condition. This has resulted, inevitably, in delays to both accurate diagnosis and effective treatment regimes. Here, we provide a standardized methodology for the description of skin conditions of rainbow trout of uncertain aetiology. We demonstrate how the approach can be used to develop case definitions, using coldwater strawberry disease as an example

Competition and parasitism in the native White Clawed Crayfish Austropotamobius pallipes and the invasive Signal Crayfish Pacifastacus leniusculus in the UK

Many crayfish species have been introduced to novel habitats worldwide, often threatening extinction of native species. Here we investigate competitive interactions and parasite infections in the native Austropotamobius pallipes and the invasive Pacifastacus leniusculus from single and mixed species populations in theUK. We found A. pallipes individuals to be significantly smaller in mixed compared to single species populations; conversely P. leniusculus individuals were larger in mixed than in single species populations. Our data provide no support for reproductive interference as a mechanism of competitive displacement and instead suggest competitive exclusion of A. pallipes from refuges by P. leniusculus leading to differential predation. We screened 52 P. leniusculus and 12 A. pallipes for microsporidian infection using PCR. We present the first molecular confirmation of Thelohania contejeani in the native A. pallipes; in addition, we provide the first evidence for T. contejeani in the invasive P. leniusculus. Three novel parasite sequenceswere also isolated fromP. leniusculus with an overall prevalence of microsporidian infection of 38% within this species; we discuss the identity of and the similarity between these three novel sequences. We also screened a subset of fifteen P. leniusculus and three A. pallipes for Aphanomyces astaci, the causative agent of crayfish plague and for the protistan crayfish parasite Psorospermium haeckeli. We found no evidence for infection by either agent in any of the crayfish screened. The high prevalence of microsporidian parasites and occurrence of shared T. contejeani infection lead us to propose that future studies should consider the impact of these parasites on native and invasive host fitness and their potential effects upon the dynamics of native-invader systems

Invaders in hot water: a simple decontamination method to prevent the accidental spread of aquatic invasive non-native species.

Watersports equipment can act as a vector for the introduction and spread of invasive non native species (INNS) in freshwater environments. To support advice given to recreational water users under the UK Government’s Check Clean Dry biosecurity campaign and ensure its effectiveness at killing a range of aquatic INNS, we conducted a survival experiment on seven INNS which pose a high risk to UK freshwaters. The efficacy of exposure to hot water (45 °C, 15 min) was tested as a method by which waters users could ‘clean’ their equipment and was compared to drying and a control group (no treatment). Hot water had caused 99 % mortality across all species 1 h after treatment and was more effective than drying at all time points (1 h: χ2 = 117.24, p < 0.001; 1 day χ2 = 95.68, p < 0.001; 8 days χ2 = 12.16, p < 0.001 and 16 days χ2 = 7.58, p < 0.001). Drying caused significantly higher mortality than the control (no action) from day 4 (χ2 = 8.49, p < 0.01) onwards. In the absence of hot water or drying, 6/7 of these species survived for 16 days, highlighting the importance of good biosecurity practice to reduce the risk of accidental spread. In an additional experiment the minimum lethal temperature and exposure time in hot water to cause 100 % mortality in American signal crayfish (Pacifastacus leniusculus), was determined to be 5 min at 40 °C. Hot water provides a simple, rapid and effective method to clean equipment. We recommend that it is advocated in future biosecurity awareness campaigns

Opinion of the Scientific Panel on Biological Hazards on a request from the European Parliament on the assessment of the health risks of feeding of ruminants with fishmeal in relation to the risk of TSE

Since Bovine Spongiform Encephalopathy (BSE) was reported for the first time in 1986 in the UK, the European Commission (EC) has developed a comprehensive set of risk reducing measures on transmissible spongiform encephalopathies (TSEs) in order to protect human health from BSE and to control and eventually eradicate TSEs in animals. This Regulation (EC No 999/2001) of the European Parliament and of the Council lays down rules for the prevention, control and eradication of certain TSEs. One of the most effective risk reducing measures consisted of a total EU wide ban on the use of processed animal protein in feeds for any animal farmed for the production of food, with some exceptions (e.g. use of fishmeal in non-ruminants). A temporary EU-wide ban on the use of fishmeal in ruminant feed has been in place since 2001 (EC 2000/766 and 2001/9). In 2003, the temporary ban was transferred into permanent measures within the TSE regulations (EC 999/2001). Fishmeal was banned because of the difficulties of detecting small amounts of ruminant proteins in feed containing fishmeal. Feed microscopy is currently the only method officially endorsed by the European Commission to test for the presence of animal protein in feeds. A revision of Regulation (EC) No 999/2001 is foreseen and the current draft revision allows feeding young ruminants with fishmeal and introduces a tolerance level for fishmeal in feed for adult cattle under strict conditions. Consideration to any lifting of this temporary ban on fishmeal use in ruminant diets should be supported by (1) a scientific risk assessment indicating if a risk of spreading BSE to ruminants through fishmeal is existing or not and (2) the development of a validated method allowing detection, identification and discrimination up to the mammalian species level of the presence of mammalian Meat and Bone Meal (mMBM) in ruminant feeds even in the presence of fish meal in the same feed. In October 2004 the European Parliament adopted a resolution where it calls on the Commission to withdraw its Draft Regulation amending Annex IV to Regulation (EC) No 999/2001 of the European Parliament and of the Council as regards animal nutrition (SANCO/3027/2004) on the consideration that the feeding of fishmeal to ruminants is not consistent with the duty imposed on the Community by Article 152(1) of the EC Treaty and that the level of public health protection can not be lowered. The European Food Safety Authority (EFSA) and its Scientific Panel on Biological Hazards was invited by the European Parliament to provide an opinion on the state of play as regards the health risks of the feeding of ruminants with fishmeal in relation to the risk of TSE and if this could it have negative consequences in terms of public health. 1 For citation purposes: Opinion of the Scientific Panel on Biological Hazards on a request from the European Parliament on the assessment of the health risks of feeding of ruminants with fishmeal in relation to the risk of TSE., The experts of the Scientific Panel on Biological Hazards concluded that if there is any risk of TSE in fishmeal, this could arise from the mammalian feed being fed to this fish or through fishmeal contaminated by Meat and Bone Meal (MBM). If and when fish meal would be allowed back into the feed chain, in terms of Public Health, the concerns remain at the level of the prevention of cross contamination with MBM. The risk of TSE in fish, either being fed directly or by amplification of infectivity is remote. Much progress is made in tests used for the detection of MBM in feed using PCR for the detection of species specific DNA in heat treated animal proteins. This progress in tests developed and the combination of different tests now allow better detection and differentiation of MBM up to the species level, however, there is still no 100% guaranteed method available. Following these conclusions, also a number of recommendations were made for further research

Correction to: Main parasitic infections in gilthead seabream and European seabass aquaculture: risk factors from stakeholders’ perspective (Aquaculture International, (2024), 10.1007/s10499-023-01374-3)

Springer No Unnumbered 2024 1 26 0 NonStandardArchiveJournal Unnumbered Regular OpenAccess OpenAccess OpenAccess OpenAccess OpenAccess OpenAccess true BodyRef/PDF/10499_2024_Article_1419.pdf Typeset OnlinePDF Erratum Life Sciences Freshwater & Marine Ecology Zoology Biomedical and Life Sciences false The corresponding author requested to update the 1st author’s affiliation (from Dorchester to London). The updated affiliation 1 is shown below: Department for Environment, Food and Rural Affairs, Aquatic Animal Health Policy, London, UK The original article has been corrected

Model for ranking freshwater fish farms according to their risk of infection and illustration for viral haemorrhagic septicaemia

We developed a model to calculate a quantitative risk score for individual aquaculture sites. The score indicates the risk of the site being infected with a specific fish pathogen (viral haemorrhagic septicaemia virus (VHSV); infectious haematopoietic necrosis virus, Koi herpes virus), and is intended to be used for risk ranking sites to support surveillance for demonstration of zone or member state freedom from these pathogens. The inputs to the model include a range of quantitative and qualitative estimates of risk factors organised into five risk themes (1) Live fish and egg movements; (2) Exposure via water; (3) On-site processing; (4) Short-distance mechanical transmission; (5) Distance-independent mechanical transmission. The calculated risk score for an individual aquaculture site is a value between zero and one and is intended to indicate the risk of a site relative to the risk of other sites (thereby allowing ranking). The model was applied to evaluate 76 rainbow trout farms in 3 countries (42 from England, 32 from Italy and 2 from Switzerland) with the aim to establish their risk of being infected with VHSV. Risk scores for farms in England and Italy showed great variation, clearly enabling ranking. Scores ranged from 0.002 to 0.254 (mean score 0.080) in England and 0.011 to 0.778 (mean of 0.130) for Italy, reflecting the diversity of infection status of farms in these countries. Requirements for broader application of the model are discussed. Cost efficient farm data collection is important to realise the benefits from a risk-based approach