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Posner hypothesised that the legalisation of assisted suicide may substitute for unassisted (unregulated) suicide. We test predictions arising from this hypothesis using data from US states that have legalised assisted suicide. Event study regression estimates provide strong evidence that legalisation of assisted suicide is associated with an increase in total suicides, especially for females and older people. There is some evidence that assisted suicide laws are also associated with a smaller increase in unassisted suicide, though the statistical significance is weaker than for total suicides. Results using the synthetic control method (SCM) are generally consistent with the regression estimates. Overall the US experience to date provides little evidence in support of the Posner substitution hypothesis.

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Foot-and-mouth disease (FMD) is an extremely infectious viral infection of cloven-hoofed animals which is highly challenging to control and can give rise to national animal health crises, especially if there is a lack of pre-existing immunity due to the emergence of new strains or following incursions into disease-free regions. The 2001 FMD epidemic in the UK was on a scale that initially overwhelmed the national veterinary services and was eventually controlled by livestock lockdown and slaughter on an unprecedented scale. In 2020, the rapid emergence of COVID-19 has led to a human pandemic unparalleled in living memory. The enormous logistics of multi-agency control efforts for COVID-19 are reminiscent of the 2001 FMD epidemic in the UK, as are the use of movement restrictions, not normally a feature of human disease control. The UK experience is internationally relevant as few countries have experienced national epidemic crises for both diseases. In this review, we reflect on the experiences and lessons learnt from UK and international responses to FMD and COVID-19 with respect to their management, including the challenge of preclinical viral transmission, threat awareness, early detection, different interpretations of scientific information, lockdown, biosecurity behaviour change, shortage of testing capacity and the choices for eradication versus living with infection. A major lesson is that the similarity of issues and critical resources needed to manage large-scale outbreaks demonstrates that there is benefit to a ‘One Health’ approach to preparedness, with potential for greater cooperation in planning and the consideration of shared critical resources.

Significant model output estimates of behavioural parameters for base and experimental model, including results of the likelihood ratio comparison.

Further information on the calculation of the air gun received levels and measured behavioural variables

The sequence diversity of viral populations within individual hosts is the starting material for selection and subsequent evolution of RNA viruses such as foot-and-mouth disease virus (FMDV). Using next-generation sequencing (NGS) performed on a Genome Analyzer platform (Illumina), this study compared the viral populations within two bovine epithelial samples (foot lesions) from a single animal with the Inoculum used to initiate experimental infection. Genomic sequences were determined in duplicate sequencing runs, and the consensus sequence determined by NGS, for the Inoculum, was identical to that previously determined using the Sanger method. However, NGS reveals the fine polymorphic sub-structure of the viral population, from nucleotide variants present at just below 50% frequency to those present at fractions of 1%. Some of the higher frequency polymorphisms identified encoded changes within codons associated with heparan sulphate binding and were present in both feet lesions revealing intermediate stages in the evolution of a tissue-culture adapted virus replicating within a mammalian host. We identified 2,622, 1,434 and 1,703 polymorphisms in the Inoculum, and in the two foot lesions respectively: most of the substitutions occurred only in a small fraction of the population and represent the progeny from recent cellular replication prior to onset of any selective pressures. We estimated an upper limit for the genome-wide mutation rate of the virus within a cell to be 7.8 x 10-4 per nt. The greater depth of detection, achieved by NGS, demonstrates that this method is a powerful and valuable tool for the dissection of FMDV populations within-hosts.

Oat hulls were assessed in laboratory and pilot plant tests as a potential pressing aid for the fruit juice industry. Laboratory tests, using 0.5–3.0% w/w press aids showed average weight yields of apple juice of 78.0, 77.5, 76.6, and 74.5% for Silvacel 116, Silvacel 133, rice hulls and whole oat hulls, respectively. A control (no press aid) gave an average juice yield of 73.0%. When oat hulls were processed into a slivered form, the average juice yield increased from 74.5% to 76.5% and compared favora bly with the yield from rice hulls. Pilot plant tests, using slivered oat hulls at the 2.0% w/w level with late season Ida Red apples, gave 77.9% juice yield compared to 71.7% for the control where the apple pulps were treated with pectinase before pressing. No quality defects were detected in the finished juice product. These results suggest an opportunity for improved oat hull utilization and a value-added contribution by oat hulls, as a replacement for more expensive press aid imports in the Canadian fruit juice processing industry.

Endemic circulation of foot-and-mouth disease (FMD) in Africa and Asia poses a continuous risk to countries in Europe, North America, and Oceania which are free from the disease. Introductions of the disease into a free region have dramatic economic impacts, especially if they are not detected at an early stage and controlled rapidly. However, farmers and veterinarians have an obvious disincentive to report clinical signs that are consistent with FMD, due to the severe consequences of raising an official suspicion, such as farm-level quarantine. One way that the risk of late detection can be mitigated is offering non-discriminatory exclusion testing schemes for differential diagnostics, wherein veterinarians can submit samples without the involvement of the competent authority and without sanctions or costs for the farmer. This review considers the benefits and limitations of this approach to improve the early detection of FMD in free countries and gives an overview of the FMD testing schemes currently in use in selected countries in Europe and the Americas as well as in Australia.

Routine detection of equine arteritis virus (EAV) can be achieved by virus isolation (VI) in cell culture, or by the amplification of viral genome by molecular methods. To simplify molecular diagnosis, a number of different Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) and RT-nested PCR (RT-nPCR) assays were compared, and a one-tube method was developed and optimised utilizing a fluorogenic probe (TaqMan ® ). An artificial RNA template (Mimic) and associated probe were also constructed to provide in-tube validation of the RT-PCR system. To assess the utility of the RT-PCR TaqMan ® assay, 28 different isolates of EAV representing different genetic groups of American and European strains were tested. Furthermore, the ability of VI and RT-PCR TaqMan ® assay to detect EAV in different biological matrices such as semen, nasal and faecal swabs and blood was compared. All 28 EAV strains were detected by the RT-PCR TaqMan ® assay. The results of TaqMan ® and VI testing were in agreement for 30 of the 33 semen samples and all of the 50 other clinical specimens examined: the RT-PCR TaqMan ® assay detected 18 positive semen samples, three more than VI. In conclusion, the one-tube RT-PCR TaqMan ® assay is a rapid, reliable method for the detection of EAV. equine arteritis virus / RT-PCR / mimic / fluorescent probe / TaqMan ®