Risk of foot and mouth disease associated with proximity in space and time to infected premises and the implications for control policy during the 2001 epidemic in Cumbria

An analysis was made that calculated the risk of disease for premises in the most heavily affected parts of the county of Cumbria during the foot-and-mouth disease epidemic in the UK in 2001. In over half the cases the occurrence of the disease was not directly attributable to a recently infected premises being located within 1.5 km. Premises more than 1.5 km from recently infected premises faced sufficiently high infection risks that culling within a 1.5 km radius of the infected premises alone could not have prevented the progress of the epidemic. A comparison of the final outcome in two areas of the county, south Penrith and north Cumbria, indicated that focusing on controlling the potential spread of the disease over short distances by culling premises contiguous to infected premises, while the disease continued to spread over longer distances, may have resulted in excessive numbers of premises being culled. Even though the contiguous cull in south Penrith appeared to have resulted in a smaller proportion of premises becoming infected, the overall proportion of premises culled was considerably greater than in north Cumbria, where, because of staff and resource limitations, a smaller proportion of premises contiguous to infected premises was culled

Farmers’ attitudes to disease risk management in England: a comparative analysis of sheep and pig farmers

The UK Department for Environment, Food and Rural Affairs (Defra) identified practices to reduce the risk of animal disease outbreaks. We report on the response of sheep and pig farmers in England to promotion of these practices. A conceptual framework was established from research on factors influencing adoption of animal health practices, linking knowledge, attitudes, social influences and perceived constraints to the implementation of specific practices. Qualitative data were collected from nine sheep and six pig enterprises in 2011. Thematic analysis explored attitudes and responses to the proposed practices, and factors influencing the likelihood of implementation. Most feel they are doing all they can reasonably do to minimise disease risk and that practices not being implemented are either not relevant or ineffective. There is little awareness and concern about risk from unseen threats. Pig farmers place more emphasis than sheep farmers on controlling wildlife, staff and visitor management and staff training. The main factors that influence livestock farmers’ decision on whether or not to implement a specific disease risk measure are: attitudes to, and perceptions of, disease risk; attitudes towards the specific measure and its efficacy; characteristics of the enterprise which they perceive as making a measure impractical; previous experience of a disease or of the measure; and the credibility of information and advice. Great importance is placed on access to authoritative information with most seeing vets as the prime source to interpret generic advice from national bodies in the local context. Uptake of disease risk measures could be increased by: improved risk communication through the farming press and vets to encourage farmers to recognise hidden threats; dissemination of credible early warning information to sharpen farmers’ assessment of risk; and targeted information through training events, farming press, vets and other advisers, and farmer groups, tailored to the different categories of livestock farmer.

The role of REST in transcriptional and epigenetic dysregulation in Huntington's disease

Huntington's disease (HD) is a devastating disorder that affects approximately 1 in 10,000 people and is accompanied by neuronal dysfunction and neurodegeneration. HD manifests as a progressive chorea, a decline in mental abilities accompanied by behavioural, emotional and psychiatric problems followed by, dementia, and ultimately, death. The molecular pathology of HD is complex but includes widespread transcriptional dysregulation. Although many transcriptional regulatory molecules have been implicated in the pathogenesis of HD, a growing body of evidence points to the pivotal role of RE1 Silencing Transcription Factor (REST). In HD, REST, translocates from the cytoplasm to the nucleus in neurons resulting in repression of key target genes such as BDNF. Since these original observations, several thousand direct target genes of REST have been identified, including numerous non-coding RNAs including both microRNAs and long non-coding RNAs, several of which are dysregulated in HD. More recently, evidence is emerging that hints at epigenetic abnormalities in HD brain. This in turn, promotes the notion that targeting the epigenetic machinery may be a useful strategy for treatment of some aspects of HD. REST also recruits a host of histone and chromatin modifying activities that can regulate the local epigenetic signature at REST target genes. Collectively, these observations present REST as a hub that coordinates transcriptional, posttranscriptional and epigenetic programmes, many of which are disrupted in HD. We identify several spokes emanating from this REST hub that may represent useful sites to redress REST dysfunction in HD.

'Nature concocts & expels': the agents and processes of recovery from disease in Early Modern England

The ‘golden saying’ in early modern medicine was ‘Nature is the healer of disease’. This article uncovers the meaning and significance of this forgotten axiom by investigating perceptions of the agents and physiological processes of recovery from illness in England, c.1580-1720. Drawing on sources such as medical texts and diaries, it shows that doctors and laypeople attributed recovery to three agents – God, Nature, and the practitioner. While scholars are familiar with the roles of providence and medicine, the vital agency of Nature has been overlooked. In theory, the agents operated in a hierarchy: Nature was ‘God’s instrument’, and the physician, ‘Nature’s servant’; but in practice the power balance was more ambivalent. Nature was depicted both as a housewife who cooked and cleaned the humours, and as a warrior, who defeated the disease. Through exploring these complex dynamics, the article sheds fresh light on concepts of gender, disease, and bodies.

Effects of carbon dioxide on the searching behaviour of the root-feeding clover weevil Sitona lepidus (Coleoptera : Curculionidae)

The respiratory emission of CO2 from roots is frequently proposed as an attractant that allows soil-dwelling insects to locate host plant roots, but this role has recently become less certain. CO2 is emitted from many sources other than roots, so does not necessarily indicate the presence of host plants, and because of the high density of roots in the upper soil layers, spatial gradients may not always be perceptible by soil-dwelling insects. The role of CO2 in host location was investigated using the clover root weevil Sitona lepidus Gyllenhall and its host plant white clover (Trifolium repens L.) as a model system. Rhizochamber experiments showed that CO2 concentrations were approximately 1000 ppm around the roots of white clover, but significantly decreased with increasing distance from roots. In behavioural experiments, no evidence was found for any attraction by S. lepidus larvae to point emissions of CO2, regardless of emission rates. Fewer than 15% of larvae were attracted to point emissions of CO2, compared with a control response of 17%. However, fractal analysis of movement paths in constant CO2 concentrations demonstrated that searching by S. lepidus larvae significantly intensified when they experienced CO2 concentrations similar to those found around the roots of white clover (i.e. 1000 ppm). It is suggested that respiratory emissions of CO2 may act as a 'search trigger' for S. lepidus, whereby it induces larvae to search a smaller area more intensively, in order to detect location cues that are more specific to their host plant.

The costs and benefits of digital dermatitis control on UK dairy farms

Digital dermatitis is a significant problem in UK dairy herds and the cost to farmers has not yet been fully quantified. Under the current farm health planning initiative there is a need to demonstrate to farmers the costs and benefits of disease control. This paper presents the first attempt to quantify the costs and benefits of digital dermatitis control on UK dairy farms through the use of an interactive model.

Comparative effect of root-knot nematode on severity of Verticillium and Fusarium wilt in cotton

The effect of root-knot nematode (RKN) (Meloidogyne incognita) on Verticillium dahliae and Fusarium oxysporum f.sp. vasinfectum in cotton (Gossypium hirsutum) was investigated. Two different inoculation methods were used, one in which inoculum was added to the soil, so that nematode and fungal inoculum were in close proximity; the other, inoculation into the stem, whereby the two inocula were spatially separated. Invasion of the roots by RKN enhanced disease severity, as measured by the height of vascular browning in the stem, following inoculation with either wilt pathogen. The effect of RKN on Fusarium wilt was more pronounced than that on Verticillium wilt. Nematode-enhanced infection by F. oxysporum is a well known effect but there are few reports of enhanced infection by Verticillium due to RKN. Relative resistance of a number of cotton cultivars to both wilt diseases, as measured by height of vascular browning, was similar to the known field performance of the cultivars. The use of vascular browning as an estimate of disease severity was therefore validated.

Design and formative evaluation of an information kiosk on cattle health for landless cattle owners

This paper describes and analyses the experience of designing, installing and evaluating a farmer-usable touch screen information kiosk on cattle health in a veterinary institution in Pondicherry. The contents of the kiosk were prepared based on identified demands for information on cattle health, arrived at through various stakeholders meetings. Information on these cattle diseases and conditions affecting the livelihoods of the poor was provided through graphics, text and audio back-up, keeping in mind the needs of landless and illiterate poor cattle owners. A methodology for kiosk evaluation based on the feedback obtained from kiosk facilitator, critical group reflection and individual users was formulated. The formative evaluation reveals the potential strength this ICT has in transferring information to the cattle owners in a service delivery centre. Such information is vital in preventing diseases and helps cattle owners to present and treat their animals at an early stage of disease condition. This in turn helps prevent direct and indirect losses to the cattle owners. The study reveals how an information kiosk installed at a government institution as a freely accessible source of information to all farmers irrespective of their class and caste can help in transfer of information among poor cattle owners, provided periodic updating, interactivity and communication variability are taken care of. Being in the veterinary centre, the kiosk helps stimulate dialogue, and facilitates demand of services based on the information provided by the kiosk screens.

Steinernema feltiae: ammonia triggers the emergence of their infective juveniles

Entomopathogenic nematodes complete their life cycles inside dead insects. The emergence of new infective juveniles from the cadaver has been attributed (but never demonstrated) to food depletion or to the accumulation of metabolites from the breakdown of the host's tissues. Here we give evidence that emergence is triggered by ammonia, a product of nematode defecation. We found that the emergence of Steinernema feltiae infective juveniles from Galleria mellonella cadavers was stimulated by a particular level of ammonia. Emergence was delayed when ammonia in the cadaver was decreased and was prompted when increased. These findings will further improve the understanding of the nematode life cycle. Here we speculate that production of infective juveniles can be mediated by ammonia and work in a manner analogous to that of the clatter recovery inhibiting factor (DRIF) in Caenorhabditis elegans. (C) 2008 Elsevier Inc. All rights reserved.

Economic impact of Turnip mosaic virus, Cauliflower mosaic virus and Beet mosaic virus in three Kenyan vegetables

Screenhouse experiments conducted in Kenya showed that inoculation of cabbage seedlings with Turnip mosaic virus (TuMV), either alone, or in combination with Cauliflower mosaic virus (CaMV), reduced the number and weight of marketable harvested heads. When viruses were inoculated simultaneously, 25% of cabbage heads were non-marketable, representing 20-fold loss compared with control. By contrast, inoculation with CaMV alone had insignificant effects on cabbage yield. This suggests that TuMV is the more detrimental of these pathogens, and its management should be a priority. Early exposure to TuMV produced cabbages that were 50% lighter than non-infected plants, but later infection was less damaging suggesting that controlling virus infection at the seedling stage is more important. TuMV was far less damaging to kale than it was to cabbage; although high proportions of TuMV-inoculated kale plants showed symptoms (> 90%), the marketability and quality of leaves were not significantly reduced, and no clear relationship existed between timing of infection and subsequent crop losses. Early inoculation of Swiss chard with Beet mosaic virus (BtMV) significantly impaired leaf quality (similar to 50% reduction in marketable leaf production), but the impact of disease was greatest in plants that had been inoculated at maturity, where average leaf losses were two and a half times those recorded in virus-free plants. Disease-management of BtMV in Swiss chard is important, therefore, not only at the seedling stage, but particularly when plants are transplanted from nursery to field.