Survival of African Swine Fever Virus in Excretions from Pigs Experimentally Infected with the Georgia 2007/1 Isolate

African swine fever virus (ASFV) causes a lethal haemorrhagic disease of swine which can be transmitted through direct contact with infected animals and their excretions or indirect contact with contaminated fomites. The shedding of ASFV by infected pigs and the stability of ASFV in the environment will determine the extent of environmental contamination. The recent outbreaks of ASF in Europe make it essential to develop disease transmission models in order to design effective control strategies to prevent further spread of ASF. In this study, we assessed the shedding and stability of ASFV in faeces, urine and oral fluid from pigs infected with the Georgia 2007/1 ASFV isolate. The half‐life of infectious ASFV in faeces was found to range from 0.65 days when stored at 4°C to 0.29 days when stored at 37°C, while in urine it was found to range from 2.19 days (4°C) to 0.41 days (37°C). Based on these half‐lives and the estimated dose required for infection, faeces and urine would be estimated to remain infectious for 8.48 and 15.33 days at 4°C and 3.71 and 2.88 days at 37°C, respectively. The half‐life of ASFV DNA was 8 to 9 days in faeces and 2 to 3 days in oral fluid at all temperatures. In urine, the half‐life of ASFV DNA was found to be 32.54 days at 4°C decreasing to 19.48 days at 37°C. These results indicate that ASFV in excretions may be an important route of ASFV transmission.ISSN:1865-1674ISSN:1865-168

The growth and strategic functioning of One Health networks: a systematic analysis.

BACKGROUND: The recent increase in attention to linkages between human health, animal health, and the state of the environment has resulted in the rapid growth of networks that facilitate collaboration between these sectors. This study ascertained whether duplication of efforts is occurring across networks, which stakeholders are being engaged, and how frequently monitoring and evaluation of investments is being reported. METHODS: This study is a systematic analysis of One Health networks (OHNs) in Africa, Asia, and Europe. We defined an OHN as an engagement between two or more discrete organisations with at least two of the following sectors represented: animal health, human health, and the environment or ecosystem. Between June 5 and Sept 29, 2017, we systematically searched for OHNs in PubMed, Google, Google Scholar, and relevant conference websites. No language restrictions were applied, but we were only able to translate from English and French. Data about OHNs, including their year of initiation, sectors of engagement, regions of operation, activities conducted, and stakeholders involved, were extracted with a standardised template and analysed descriptively. FINDINGS: After screening 2430 search results, we identified and analysed 100 unique OHNs, of which 86 were formed after 2005. 32 OHNs covered only human and animal health, without engaging with the role of the environment on health. 78 OHNs involved academic bodies and 78 involved government bodies, with for-profit organisations involved in only 23 and community groups involved in only ten. There were few collaborations exclusively between networks in the developing world (four OHNs) and only 15 OHNs reported monitoring and evaluation information. The majority of OHNs worked on supporting communication, collaboration, information sharing, and capacity building. INTERPRETATION: Amid concerns about there being insufficient strategic direction and coordination in the growth of OHNs, our study provides empirical evidence about limitations in stakeholder representation, apparently absent or ambiguous monitoring and evaluation structures, and potential areas of duplication. The collective strategic functioning of OHNs might be improved by more transparent reporting of goals and outcomes of OHN activities, as well as more collaborations led by networks within the developing world and increased attention to environmental health. FUNDING: None

African horse sickness: The potential for an outbreak in disease-free regions and current disease control and elimination techniques

African horse sickness (AHS) is an arboviral disease of equids transmitted by Culicoides biting midges. The virus is endemic in parts of sub-Saharan Africa and official AHS disease-free status can be obtained from the World Organization for Animal Health on fulfilment of a number of criteria. AHS is associated with case fatality rates of up to 95%, making an outbreak among naïve horses both a welfare and economic disaster. The worldwide distributions of similar vector-borne diseases (particularly bluetongue disease of ruminants) are changing rapidly, probably due to a combination of globalisation and climate change. There is extensive evidence that the requisite conditions for an AHS epizootic currently exist in disease-free countries. In particular, although the stringent regulations enforced upon competition horses make them extremely unlikely to redistribute the virus, there are great concerns over the effects of illegal equid movement. An outbreak of AHS in a disease free region would have catastrophic effects on equine welfare and industry, particularly for international events such as the Olympic Games. While many regions have contingency plans in place to manage an outbreak of AHS, further research is urgently required if the equine industry is to avoid or effectively contain an AHS epizootic in disease-free regions. This review describes the key aspects of AHS as a global issue and discusses the evidence supporting concerns that an epizootic may occur in AHS free countries, the planned government responses, and the roles and responsibilities of equine veterinarians.Matthew Robin's clinical training scholarship was funded by the Horserace Betting Levy Board.http://onlinelibrary.wiley.com/journal/10.1001/(ISSN)2042-33062017-09-30hb2017Companion Animal Clinical Studie

Salmonella Brandenburg in sheep meat in New Zealand : preliminary studies to support a risk assessment approach : a thesis presented in partial fulfillment of the requirements for the degree of Masters of Veterinary Sciences in Veterinary Public Health at Massey University, Palmerston North, New Zealand

Abortion and death of ewes caused by a particular strain of Salmonella Brandenburg is an animal disease problem that is unique to the South Island of New Zealand. Like most Salmonella serovars, this organism is zoonotic and has caused cases in occupationally exposed people. As Salmonella are primarily recognised as agents of foodborne disease, the potential for foodborne transmission must be acknowledged, although human cases attributed to consumption of sheep meat have not yet been reported. Salmonella Brandenburg has an additional concern for New Zealand’s sheep meat industry owing to the possibility that contamination of sheep meat products could compromise market access. In 1995, the Sanitary Phytosanitary Agreement of the World Trade Organisation specified that scientific risk analysis was required before countries could refuse to import animal or plant materials on the basis of risks to animal, plant, or human health. This thesis presents initial microbiological studies of the prevalence and concentration of Salmonella Brandenburg on sheep meat carcasses that were conducted in conjunction with other projects designed to address the Salmonella Brandenburg issue using a modern risk assessment approach. The microbiological studies (Chapters 3 and 4) are preceded by two introductory discussions that provide the context for the project. Chapter 1 presents an overview of national and international regulatory approaches to food safety, foodborne diseases and protection of consumer health relevant to meat and meat products. A selective review of literature on Salmonella focuses on Salmonella in sheep and on aspects most relevant to food safety. Chapter 2 summarises information on published quantitative microbiological risk assessments (QRA) conducted using the guidelines developed by the Codex Alimentarius Commission to apply QRA to microbiological foodborne hazards. A conceptual framework is presented for developing a QRA for Salmonella Brandenburg in sheep meat that covers all sectors of the food supply chain from animal production to the point of consumption. Following the precedent of previous QRA efforts, the food supply chain is divided into a series of five modules: animal production; transport and lairage; slaughter and processing; retail and distribution; and consumer. For each module, key outputs (prevalence and concentration of Salmonella in animals or product at various points in the supply chain), and their likely determinants, are identified. The specific objective of the microbiological studies conducted was to estimate the prevalence and i concentration of Salmonella on sheep carcasses from animals originating from farms that had experienced Salmonella Brandenburg disease and other farms from the same region that had no history of this disease. Prior to undertaking the field studies, it was necessary to conduct some methodological studies to evaluate the effect of sample handling procedures on the results obtained with quantitative bacteriology. Chapter 3 presents three controlled laboratory experiments with swab samples taken from meat contaminated experimentally with the epidemic strain of Salmonella Brandenburg. The Most Probably Number (MPN) method was used to quantify counts of Salmonella Brandenburg per 100cm2 area of meat swabbed. In each experiment, control samples were processed immediately, and treatment samples were subjected to different periods and conditions of storage. Treatments were chosen to emulate anticipated conditions that would be required for the field studies due to logistic constraints. The three storage protocols evaluated were: Experiment 1: Storage of swabs diluted in buffered peptone water (BPW) for 48h at 40C Experiment 2: Storage of swabs diluted in BPW for 5 days at 40C Experiment 3: Storage of swabs for 24h at 40C before dilution in BPW, followed by storage for a further 48h at 40C. Differences in counts between control and treatment samples were not tested statistically, owing to the small samples sizes, but were numerically less than one log difference in all experiments. In 2 of the 3 experiments, counts for stored samples were in fact numerically greater than for samples processed immediately. These results suggested that carcass swabs contaminated with Salmonella could be stored under the specified conditions without affecting the results of quantitative bacteriology using the MPN method. Chapter 4 presents a study undertaken to obtain initial qualitative and quantitative estimates of the presence of Salmonella organisms on sheep carcasses sampled at 3 points in the processing chain (i.e. slaughter floor, cooler, and boning room). Slaughtered sheep (ewes and lambs) were sourced from six farms in the Central Otago/Southland region of the South Island where Salmonella Brandenburg disease is endemic. Three farms (case farms) were selected based on the occurrence of an outbreak of Salmonella Brandenburg ii disease during the spring of 2000. Three non-case farms from the same region were also sampled. As the disease epidemics are temporally clustered in July and August, well before lambs are sent for slaughter, sampling was replicated after an interval of approximately 2 months to assess likely temporal variation in risk of carcass contamination. For comparative purposes, samples from sheep carcasses were also collected from 6 groups of sheep slaughtered at 2 plants in the North Island where salmonellosis due to Salmonella Brandenburg infection in sheep has not been reported. A total of 1417 carcasses were sampled in the study and initially tested by BAX® test. Of these, 1214 samples were sourced from the 3 case and 3 non-case farms supplying the South Island plant. The remaining 203 carcasses were sampled at the 2 North Island plants. A total of 138 (11.3%) of the 1214 samples collected in the South Island plant tested positive for the presence of Salmonella Brandenburg. No positive findings were obtained from the samples collected in the North Island plants. The vast majority (130 or 94%) of the 138 positive samples was obtained in the first period of sampling, indicating a substantial decline in risk of carcass contamination in the period between the first and second sampling. These findings indicated that the prevalence of carcass contamination with Salmonella Brandenburg was markedly elevated in the region where sheep flocks experienced abortion outbreaks caused by the organism. Although clinical Salmonella Brandenburg enteric disease has not been reported in lambs, the first sampling revealed that overall prevalence of contamination was higher (33%) for lamb carcasses than ewe carcasses (10%) from the same farms. While the prevalence of lamb carcass contamination was comparable for both case and non-case farms, the prevalence of ewe carcass contamination was strongly clustered and only 2 samples were positive from non-case farms. Estimates of the prevalence of contamination were influenced by the location of sampling carcasses (e.g. slaughter floor, cooler), but estimates of bacterial numbers on positive carcasses were generally similar regardless of class of stock, time of sampling, or sampling location in the plant. No positive samples were obtained from swabs of primary cuts in the boning room. Collectively these findings suggest that the emergence of Salmonella Brandenburg infection of sheep in the South Island may have considerable implications for product safety and public health. A strong case can be made for more research to better characterise the potential risks and to explore potential risk mitigation strategies. While the data obtained in this study have provided valuable insights into several important aspects of the issue, due to logistic and other constraints they have considerable shortcomings with respect to the requirements of the formal QRA. These shortcomings were discussed and evaluated in terms of representativeness and suitability for quantitative risk assessment. Chapter 5 presents an extension of the conceptual framework for a QRA outlined in Chapter 2, by integrating the data obtained from the bacteriological study, as well as data from other sources. Major data gaps are identified and suggestions are presented with respect to options for ongoing research to advance understanding and management of Salmonella Brandenburg in New Zealand sheep meat. More extensive and representative surveys are required to obtain more reliable data on farm, and within-farm, prevalence of infection as well as more extensive and representative longitudinal studies of the prevalence and concentration of the organism during slaughter and processing. It is considered that more systematic surveys at the time of apparent highest risk would be a more reliable means of assessing potential exposure of consumers than predictive microbiology

The growth and strategic functioning of One Health networks: a systematic analysis

Background: The recent increase in attention to linkages between human health, animal health, and the state of the environment has resulted in the rapid growth of networks that facilitate collaboration between these sectors. This study ascertained whether duplication of efforts is occurring across networks, which stakeholders are being engaged, and how frequently monitoring and evaluation of investments is being reported. Methods: This study is a systematic analysis of One Health networks (OHNs) in Africa, Asia, and Europe. We defined an OHN as an engagement between two or more discrete organisations with at least two of the following sectors represented: animal health, human health, and the environment or ecosystem. Between June 5 and Sept 29, 2017, we systematically searched for OHNs in PubMed, Google, Google Scholar, and relevant conference websites. No language restrictions were applied, but we were only able to translate from English and French. Data about OHNs, including their year of initiation, sectors of engagement, regions of operation, activities conducted, and stakeholders involved, were extracted with a standardised template and analysed descriptively. Findings: After screening 2430 search results, we identified and analysed 100 unique OHNs, of which 86 were formed after 2005. 32 OHNs covered only human and animal health, without engaging with the role of the environment on health. 78 OHNs involved academic bodies and 78 involved government bodies, with for-profit organisations involved in only 23 and community groups involved in only ten. There were few collaborations exclusively between networks in the developing world (four OHNs) and only 15 OHNs reported monitoring and evaluation information. The majority of OHNs worked on supporting communication, collaboration, information sharing, and capacity building. Interpretation: Amid concerns about there being insufficient strategic direction and coordination in the growth of OHNs, our study provides empirical evidence about limitations in stakeholder representation, apparently absent or ambiguous monitoring and evaluation structures, and potential areas of duplication. The collective strategic functioning of OHNs might be improved by more transparent reporting of goals and outcomes of OHN activities, as well as more collaborations led by networks within the developing world and increased attention to environmental health. Funding: None