Lack of disease surveillance in small companion animals worldwide has contributed to a deficit in our ability to detect and respond to outbreaks. In this paper we describe the first real-time syndromic surveillance system that conducts integrated spatio-temporal analysis of data from a national network of veterinary premises for the early detection of disease outbreaks in small animals. We illustrate the system's performance using data relating to gastrointestinal disease in dogs and cats. the data consist of approximately one million electronic health records for dogs and cats, collected from 458 UK veterinary premises between March 2014 and 2016. For this illustration, the system predicts the relative reporting rate of gastrointestinal disease amongst all presentations, and updates its predictions as new data accrue. The system was able to detect simulated outbreaks of varying spatial geometry, extent and severity. The system is flexible: it generates outcomes that are easily interpretable; the user can set their own outbreak detection thresholds. the system provides the foundation for prompt detection and control of health threats in companion animals. Surveillance systems have been developed globally for animal and/or public health purposes, facilitating the prevention and control of disease or infection nationally and regionally. During the past decade, the emergence of new diseases 1 and the increasing threat of bio-terrorism have motivated the development of syndromic surveillance systems in public health focused on the early detection of health threats that require effective public health action 2,3 . Syndromic surveillance uses health-related data that precedes diagnosis. Although data of this kind are less specific than data from confirmed diagnoses they are typically more timely, which is an important consideration for real-time or near-real-time analysis and interpretation 4 . In veterinary medicine the development of systems for early health-event detection has followed a similar path to that previously taken in public health 5 . A recent inventory of current and planned European veterinary syndromic surveillance systems showed wide interest in European countries for syndromic surveillance, but also highlighted the novelty of this field 6 . Small companion animal populations largely lack co-ordinated national and international disease surveillance. This has produced a deficit in our understanding of the dynamics and burden of the full range of endemic/ emerging diseases in companion animals and leaves these populations susceptible to the emergence of health threats. Lack of disease surveillance also has implications for human health, as approximately 75 percent of new and emerging diseases are zoonotic 7 . However, as health records become digitised in veterinary practices they become more available for research 8 , providing an opportunity to improve companion animal syndromic surveillance in clinical settings and the possibility of linking this with human syndromic surveillance. Recently, electronic syndromic surveillance data on companion animals has become available in real-time on a national scale www.nature.com/scientificreports www.nature.com/scientificreports/ without adjustment, on the grounds that multiple visits occurring within a short time period (e.g. within a few days) would likely indicate a more serious illness episode. Data summary. Of the 1,211,326 consultations collected between 1 st March 2014 and 29 th February 2016, 72.3% were for dogs and 27.7% for cats. In 80.7% of all consultations a valid age, breed-status (purebred or crossbred) and owner's full postcode were recorded; this subset of data is used for model selection and the basis for simulations. Gastrointestinal disease accounted for 4.0% of all presentations, amongst which 91.5% were recorded between Monday and Friday. Amongst animals presenting for GI disease, there was not a notable gender bias; 48.5% of dog consultations and 50.6% of cat consultations with a recorded sex were female. Where the breed-status was identified, 84.9% of dog GI disease consultations and 17.2% of cat GI disease consultations were purebreds. In animals with a date of birth recorded within the range 0 to 25 years, 65.4% of dog GI disease consultations and 47.4% of cat GI disease consultations were under eight years. The age profile of dogs and cats presenting for GI disease at SAVSNET veterinary premises stratified by sex and breed-status is shown in Table 1 . Data for the two species were analysed separately. We used the pet owner's home postcode to assign a measure of deprivation to each owner using the most recent English 17 , Scottish 18 and Welsh 19 Indices of Multiple Deprivation (IMD) produced by their respective governments. A detailed description of how each government has developed their own measure of deprivation can be found elsewhere [20] [21] [22] . The three country-specific IMD measures are not directly comparable. We therefore included country as a three-level factor and rescaled the ranks of each country's set of IMD scores to the range 0 to 1. For example, if for England the maximum rank was 32,000 and a location had rank 100 then the owner IMD explanatory variable would be assigned a value of 100/32,000. • Scheme 1: The outbreak only affects the central premise of each set. For each, we simulate outbreaks of different severities, in which the probability of a case is 0.1, 0.15 or 0.2. This gives a total of 9 scenarios. • Scheme 2: The outbreak affects the central premise and all of its neighbouring premises. This leads to another 6 separate scenarios, as Schemes 1 and 2 are identical for the sparse set. Scientific RepoRtS | (2019) 9:17738 | https://doi.
Output: 6 NIHR Health Protection Research Unit in Gastrointestinal Infections