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The transfer of thoracic duct lymphocytes from sheep inoculated 14 days, but not 7 days previously with bluetongue virus into their monozygotic twin resulted in some protection from challenge with bluetongue virus. T cell enrichment of the 14 day thoracic duct lymphocyte population resulted in a similar effect, indicating the T cell basis of the observed protection. Animals recovered from infection with bluetongue virus type 3 and which received thoracic duct lymphocytes from an identical twin recently infected with the same bluetongue virus type were protected from challenge with bluetongue type 4. These observations suggest that T lymphocytes play an important rote in protection against bluetongue virus. [ABSTRACT FROM AUTHOR]

Mice immunized with a single bluetongue (BT) virus type were shown to produce cytotoxic I lymphocytes (CTL's) which cross-reacted with a number of BT virus types virus. These cross-reactive CTL's could be induced by both primary in vivo and secondary in vitro stimulation. A varying degree of cross- reactivity occurred with the six BT types examined. Aspects of the character of this cross-reactivity were examined and its role in protection from disease and vaccination strategy is discussed. [ABSTRACT FROM AUTHOR]

The article presents information on papers related to viral infections cited at the meeting of the British Society of Immunology held in November 1985. One report suggests that the role of virologists in immunology is to discover ways in which a virus becomes persistent while an immunologist investigates why the immune system failed. Rubella virus can be detected in animals through their organs and secretions. In feline leukaemia virus, the provirus is incorporated into the host's DNA and is retained in new cell progeny.

Smoking tobacco is a major public health issue and a significant cause of increased mortality. People with a first episode of psychosis are more likely to smoke and the subgroup that goes on to have schizophrenia will have a significantly reduced life expectancy to the general population. The City & Hackney Early and Quick Intervention in Psychosis Team is a community mental health team at East London NHS Foundation Trust, providing outpatient care for adults presenting with first episode psychosis. This project aimed to increase the number of smoking cessation referrals from EQUIP to national smoking cessation services to 15% of the total team caseload over 6 months initially. A secondary measure was to complete an assessment of the smoking status for 90% of the caseload at all times. Change ideas were tested using plan-do-study-act cycles. A smoking cessation referral pathway was created and disseminated to the outpatient and inpatient services. The project was discussed at least monthly at the clinical team meeting. An education and skills building session was organised and took place at the team away day and an education drop-in session for patients was organised. The project was slow to take-off and patient participation was essential in driving progress. The aim was achieved at 23 months. A collateral benefit indicated that 25.7% of the total number of smokers had been recorded as having stopped smoking during the course of this project. This project demonstrates the effectiveness of quality improvement methodology facilitated by efficient leadership, collaborative teamwork, patient participation and persistence to address a complex problem that has significant consequences to patient health., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Peste des petits ruminants (PPR) is a highly infectious disease of sheep and goats that is caused by PPR virus, a member of the genus Morbillivirus that includes the viruses that cause rinderpest (RP) in cattle. RP was the first animal disease to be globally eradicated in 2011 and is only the second disease, after smallpox, to have ever been eradicated. PPR is one of the principal constraints to small ruminant production in Africa, Asia, and the Middle East. The epidemiology of PPR and RP as well as the technologies available for their diagnosis and control are similar. The conditions that favored the eradication of RP are also largely present for PPR. In this work, we outline the evolving strategy for eradication in light of current opportunities and challenges, as well as the lessons from other eradication programs in animal and human health. The global PPR situation and technology for its control are summarized. A strategy based on the lessons from previous eradication efforts that integrate epidemiology, social science, and economics as tools to target and motivate vaccination is summarized. Major aspects of the cost and benefit-cost analysis of the indicated program are presented. The overall undiscounted cost of eradication was estimated as $3.1 billion, and the benefit-cost ratio for the most likely scenario was estimated at 33.8. We close with a discussion of the possible next steps., (Copyright © 2016 by The American Association of Immunologists, Inc.)

Peste des petits ruminants (PPR) is an important cause of mortality and production loss among sheep and goats in the developing world. Despite control efforts in a number of countries, it has continued to spread across Africa and Asia, placing an increasing burden on the livelihoods of livestock keepers and on veterinary resources in affected countries. Given the similarities between PPR and rinderpest, and the lessons learned from the successful global eradication of rinderpest, the eradication of PPR seems appealing, both eliminating an important disease and improving the livelihoods of the poor in developing countries. We conducted a benefit-cost analysis to examine the economic returns from a proposed programme for the global eradication of PPR. Based on our knowledge and experience, we developed the eradication strategy and estimated its costs. The benefits of the programme were determined from (i) the averted mortality costs, based on an analysis of the literature, (ii) the downstream impact of reduced mortality using a social accounting matrix, and (iii) the avoided control costs based on current levels of vaccination. The results of the benefit-cost analysis suggest strong economic returns from PPR eradication. Based on a 15-year programme with total discounted costs of US$2.26 billion, we estimate discounted benefits of US$76.5 billion, yielding a net benefit of US$74.2 billion. This suggests a benefit cost ratio of 33.8, and an internal rate of return (IRR) of 199%. As PPR mortality rates are highly variable in different populations, we conducted a sensitivity analysis based on lower and higher mortality scenarios. All the scenarios examined indicate that investment in PPR eradication would be highly beneficial economically. Furthermore, removing one of the major constraints to small ruminant production would be of considerable benefit to many of the most vulnerable communities in Africa and Asia.

A transdisciplinary, One Health approach is proposed for the coordination of wildlife health diagnostics, research, and policy development. In some countries, considerable effort has been made to establish specific activities including surveillance and integration of wildlife health within diagnostic and research laboratories. We suggest that some of these activities can be improved and many countries still require national structures to deal with wildlife disease investigation and management. We also suggest that scientists in this field should actively engage with national and international organizations and conferences to influence the development of policy, diagnostics, research, and management of emerging wildlife diseases.

This paper recounts the history of One Health; the philosophy behind the initiative; and the current situation at the international, national, and regional level. It cites examples of where a One Health approach has successfully delivered.

Regulations are a part of life but who writes them, what is the basis on which they are written and when the regulations get it wrong, whose fault is it? Is it those who wrote the regulations, those enforcing the regulations, those being regulated or the science underpinning the regulations? In seeking answers to these questions, this paper explores the regulatory process and the contribution of science. It takes as examples the role of the Australian Pesticides and Veterinary Medicines Authority (APVMA) in regulating veterinary products, of the Security Sensitive Biological Agents regulations in managing the risks from specific pathogens, the Quarantine Act regulations as applied to containment facilities and the development of welfare standards. By dealing with products, pathogens, places and "pets" it provides a broad oversight of how regulations have been developed and applied from different perspectives and highlights the differing roles that science and research play both in developing policy and regulations. What is clear is that in the presence of good science it is usually possible to develop sound and defensible regulations e.g. those managed by APVMA, but when there is a lack of science to underpin the regulations, problems can arise e.g. in the case of animal welfare., (© Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL) 2014.)

To understand and better control AI outbreaks, not only is it necessary to understand the biology of influenza viruses but also the natural history of the hosts in which these viruses multiply and the different environments in which the hosts and viruses interact. This includes the anthropogenic factors that have influenced where, whether and how avian influenza (AI) viruses can replicate and transmit between wild birds and poultry, and between poultry and mammals, including factors influencing uptake and application of appropriate control and preventive measures for AI. This disease represents one of the best examples of the need for a 'One Health' approach to understand and tackle disease with an increasing need to comprehend and unravel the environmental and ecology drivers that affect the virus host interactions. This forum piece seeks to bring together these aspects through a review of recent outbreaks and how a deeper understanding of all three aspects, the virus, the host and the environment, can help us better manage future outbreaks.

Wildlife, especially mammals and birds, are hosts to an enormous number of viruses, most of which we have absolutely no knowledge about even though we know these viruses circulate readily in their specific niches. More often than not, these viruses are silent or asymptomatic in their natural hosts. In some instances, they can infect other species, and in rare cases, this cross-species transmission might lead to human infection. There are also instances where we know the reservoir hosts of zoonotic viruses that can and do infect humans. Studies of these animal hosts, the reservoirs of the viruses, provide us with the knowledge of the types of virus circulating in wildlife species, their incidence, pathogenicity for their host, and in some instances, the potential for transmission to other hosts. This paper describes examples of some of the viruses that have been detected in wildlife, and the reservoir hosts from which they have been detected. It also briefly explores the spread of arthropod-borne viruses and their diseases through the movement and establishment of vectors in new habitats., (Copyright © 2013 Elsevier B.V. All rights reserved.)

This paper describes those components of governance and management of a public veterinary laboratory that are deemed essential for the effective delivery of a diagnostic service. Whilst broadly applicable to all veterinary diagnostic services, there is a focus on publicly supported veterinary diagnostic laboratories in developing countries, highlighting the critical components that should be established as a minimum. The need for establishing overarching ownership, governance and resourcing is emphasised but followed by a detailed account of the components of diagnostic service management and delivery, linked to a description of the key support services that are essential in assisting delivery. Elements of quality assurance and compliance are described, with an emphasis on the need to both understand and meet the regulatory environment in which a diagnostic laboratory now operates. The outputs from a veterinary laboratory must be rooted in sound science, and mechanisms must be in place to prevent corrupt practices and inappropriate political influences.

In August 2007 Australia experienced its first outbreak of equine influenza. The disease occurred first in a quarantine station for imported horses near Sydney and subsequently escaped into the general horse population. After an extensive campaign the disease was eradicated and Australia is again recognised as free of this disease. Equine influenza was then, and is now, recognised to be the major disease risk associated with live horse imports into Australia and measures designed to mitigate this risk formed the basis of the quarantine protocols then in place. Subsequent investigations into the cause of the outbreak identified failures in compliance with these quarantine requirements as a contributing factor. It is also likely that the immunity of horses vaccinated as part of the import protocol was less than optimal, and that this had a significant role to play in the escape of the disease from quarantine.

During 2007, large outbreaks of equine influenza (EI) caused by Florida sublineage Clade 1 viruses affected horse populations in Japan and Australia. The likely protection that would be provided by two modern vaccines commercially available in the European Union (an ISCOM-based and a canarypox-based vaccine) at the time of the outbreaks was determined. Vaccinated ponies were challenged with a representative outbreak isolate (A/eq/Sydney/2888-8/07) and levels of protection were compared.A group of ponies infected 18 months previously with a phylogenetically-related isolate from 2003 (A/eq/South Africa/4/03) was also challenged with the 2007 outbreak virus. After experimental infection with A/eq/Sydney/2888-8/07, unvaccinated control ponies all showed clinical signs of infection together with virus shedding. Protection achieved by both vaccination or long-term immunity induced by previous exposure to equine influenza virus (EIV) was characterised by minor signs of disease and reduced virus shedding when compared with unvaccinated control ponies. The three different methods of virus titration in embryonated hens' eggs, EIV NP-ELISA and quantitative RT-PCR were used to monitor EIV shedding and results were compared. Though the majority of previously infected ponies had low antibody levels at the time of challenge, they demonstrated good clinical protection and limited virus shedding. In summary, we demonstrate that vaccination with current EIV vaccines would partially protect against infection with A/eq/Sydney/2888-8/07-like strains and would help to limit the spread of disease in our vaccinated horse population., (INRA, EDP Sciences, 2009)

The outbreaks of foot-and-mouth disease (FMD) in Europe in 2001 identified the vulnerability of the intensive agricultural industries in Europe and North America to the economic consequences of the introduction of a highly infectious animal disease. The very large illegal international trade in animal products bypasses the safeguards recommended by World Animal Health Organization (OIE) and put in place by governments to prevent the importation of foreign pathogens. If it is not possible to stop the entry of FMD virus, what are the options to mitigate the risk by reducing the area of the globe in which FMD is endemic? There are a number of constraints that would prevent global control of FMD; current vaccines are expensive, have a narrow antigenic spectrum, provide only short term immunity and are very fragile; diagnostics are also expensive, require training to use and if not handled properly lose sensitivity and specificity; we still do not understand the significance of carrier animals in the epidemiology of FMD, and whether it is necessary or possible to prevent the carrier state; and many decision support tools, such as models are currently more dangerous than useful in that they fail to fully accommodate all the complexities of the disease. The four national foreign animal disease laboratories in USA, Canada, UK and Australia together with the International Livestock Research Institute have put forward a proposal to address some of these constraints (the Global FMD Research Alliance, GFRA), not only to protect their own national livestock industries, but also to support FMD control programs in countries in which the disease is present.

Since the 1980s, a number of key events have significantly altered our ideas on biosecurity and the role of biocontainment laboratories, such as the bovine spongiform encephalopathy (BSE) and severe acute respiratory syndrome (SARS) outbreaks and the anthrax episode of 2001 in the USA. This has resulted in the development of plans to build "high containment" facilities around the world and an array of new regulations at both national and international levels regarding the management of pathogens, the operation of high containment facilities, the use of genetically modified material, and the transportation of such agents and personnel security issues. Considering the cost, however, it is debatable whether every country needs to build its own high containment facility. The Australian Animal Health Laboratory (AAHL) provides an example of what might be considered best practice in biocontainment while considering regulations, cost and need.

This paper describes an objective system of monitoring the performance of disease surveillance. The system was developed through dialogue with a number of countries in Africa and adopted as part of the Global Rinderpest Eradication Programme of the Food and Agriculture Organization of the United Nations. The performance monitoring system uses a clinical stomatitis-enteritis case definition, an outbreak investigation classification scheme, and a series of eight performance indicators to measure the sensitivity, specificity and timeliness of the surveillance system. Field-testing indicates that the approach is successful when good record-keeping is practiced and highlights the importance of dialogue in helping to ensure that the system is simple and acceptable. The system provides a quantitative measure of the efficacy of national disease surveillance programmes and of the quality of data derived from such programmes for use in international disease control, animal health information exchange and trade risk analysis.

The problems facing veterinary diagnostic laboratories in developing countries range from simple problems, such as limited funds to keep good personnel or obtain equipment, supplies, reagents or training, to the more complex problems of designing and executing appropriate sample collection schemes for disease surveillance of evaluating the performance characteristics of a new diagnostic assay. While many developing countries are addressing these problems independently and a number of international and national organisations provide various forms of external support, the Office International des Epizooties (OIE) must continue in its critical role to provide guidelines for the most appropriate diagnostic assays for trade purposes and the development of the primary reference reagents for these assays. In addition, the OIE should take the lead in development of quality management guidelines for veterinary diagnostic testing laboratories. Without these guidelines and standards, diagnostic laboratories in developing countries will have difficulty in gaining the credibility necessary to help improve the positions of their countries in the international trade of livestock and livestock commodities.

Reference standards are used to calibrate similar assay systems against an international reference protocol and to provide a template for the preparation of secondary and/or working standards. Three reference standards are recommended for the indirect enzyme-linked immunosorbent assay: a strong positive standard, a weak positive standard and a negative serum standard. The negative standard should be derived from a single serum or from a serum pool which exhibits typical background activity in the reference protocol. The strong and weak positive standards should be derived from a single serum or from a serum pool which typifies the humoral response (antibody) to natural infection. Suitable candidates for the positive reference standards should exhibit dose/response curves in the mid-range of antibody activity. The strong and weak positive standards should each be prepared from a one-time dilution in the negative standard, to yield antibody activities which are defined by specific points on the linear portion of the dose/response curve. The strong positive standard should represent an antibody activity (absorbance value) midway between the upper and central points and the weak positive standard should represent an antibody activity midway between the central and lower points of the linear portion of the curve. Owing to inherent differences among assay systems, antibody activities should be expressed in relative rather than in absolute terms. It is recommended that the antibody activity of the strong positive standard should denote 100% positivity. The activities of the weak positive and negative standards should then be expressed as relative percentages. Every set of international reference standards should be accompanied by an information sheet which includes, among other things, a plot of the dose/response curve and an indication of the dilutions used to prepare the standards.

Enzyme-linked immunosorbent assay (ELISA) techniques for the detection of antibodies are now widely used throughout the world for the diagnosis of infectious diseases in veterinary medicine. Although many laboratories have independently developed ELISA techniques for their own purposes, little progress has been made with respect to the international standardisation and validation of these techniques. This lack of international conformity is of major concern to organisations such as the Office International des Epizooties (OIE), the United Nations Food and Agriculture Organisation (FAO), the World Health Organisation (WHO) and the International Atomic Energy Agency (IAEA) which are involved in the establishment of international guidelines and programmes for the control, surveillance and/or eradication of infectious diseases. In this regard, a Joint FAO/IAEA Meeting of Consultants was convened in Vienna in January 1992 to review aspects of ELISA data expression, primary reference standards, quality assurance and diagnostic validation. Based on the consensus derived from this meeting, the authors describe procedures which are recommended as a platform on which to build definitive guidelines for international standardisation of ELISA protocols and reagents, in cooperation with the OIE and the OIE Reference Laboratories.