Cars dent, horse riders break: Analysis of police-recorded injury incidents involving ridden horses on public roads in Great Britain.

INTRODUCTION: Police-recorded road injury data are frequently used to approximate injury risk for different road user groups but a detailed analysis of incidents involving ridden horses has not previously been conducted. This study aims to describe human injuries resulting from interactions between ridden horses and other road users on public roads in Great Britain and identify factors associated with severe to fatal injuries. METHOD: Police-recorded road incident data involving ridden horses (2010-2019) were extracted from the Department for Transport (DfT) database and described. Multivariable mixed-effects logistic regression modeling was used to identify factors associated with severe/fatal injury outcomes. RESULTS: A total of 1,031 injury incidents involving ridden horses were reported by police forces, involving 2,243 road users. Out of 1,187 road users injured, 81.4% were female, 84.1% were horse riders, and 25.2% (n = 293/1,161) were in the 0-20 year age category. Horse riders represented 238/267 serious injuries and 17/18 fatalities. Vehicle types involved in incidents where horse riders were seriously/fatally injured were mostly cars (53.4%, n = 141/264) and vans/light goods vehicles (9.8%, n = 26). Horse riders, cyclists, and motorcyclists had higher odds of severe/fatal injury compared to car occupants (p < 0.001). Severe/fatal injuries were more likely on roads with 60-70 mph speed limits versus 20-30 mph roads, while odds of severe/fatal injury increased with increasing road user age (p < 0.001). CONCLUSIONS: Improved equestrian road safety will largely impact females and young people as well as reducing risk of severe/fatal injuries in older road users and those using modes of transport such as pedal-cycles and motorcycles. Our findings support existing evidence that reductions in speed limits on rural roads would help reduce the risk of serious/fatal injuries. PRACTICAL APPLICATIONS: More robust equestrian incident data would better inform evidence-based initiatives to improve road safety for all road users. We suggest how this can be done.

Equestrian Road Safety in the United Kingdom: Factors Associated with Collisions and Horse Fatalities.

Over 60% of UK horse riders report having experienced a road-related near-miss or accident. The aim of this study was to describe horse-related road incidents (n = 4107) reported to the British Horse Society (2010-2020) and to identify factors associated with higher odds of collisions with another vehicle and horse fatalities using multivariable logistic regression modelling. Drivers passed the horse too closely in 84.2% of incidents while road rage and speeding were reported in 40.3% and 40.1% of incidents, respectively. Close passing distance alone (odds ratio [OR] 18.3, 95% confidence interval [CI] 6.5, 51.6) or in combination with speeding (OR 4.4, CI 1.7, 11.7) was associated with higher collision odds compared to speeding alone. Speeding was, however, associated with higher horse fatality odds (OR 2.3, CI 1.2, 4.6). Wearing high visibility clothing reduced odds of collision (OR 0.2, CI 0.1, 0.4). A fatal injury to a horse was almost 12 times as likely to result in severe to fatal rider/handler injury. Loose horses contribute significantly to road-related horse fatalities. Driver behaviour of how to pass horses safely on UK roads needs further improvement and will help reduce the risk of collisions and horse and human fatalities.

Post-outbreak African horse sickness surveillance: A scenario tree evaluation in South Africa's controlled area.

An African horse sickness (AHS) outbreak occurred in March and April 2016 in the controlled area of South Africa. This extended an existing trade suspension of live equids from South Africa to the European Union. In the post-outbreak period ongoing passive and active surveillance, the latter in the form of monthly sentinel surveillance and a stand-alone freedom from disease survey in March 2017, took place. We describe a stochastic scenario tree analysis of these surveillance components for 24 months, starting July 2016, in three distinct geographic areas of the controlled area. Given that AHS was not detected, the probability of being free from AHS was between 98.3% and 99.8% assuming that, if it were present, it would have a prevalence of at least one infected animal in 1% of herds. This high level of freedom probability had been attained in all three areas within the first 9 months of the 2-year period. The primary driver of surveillance outcomes was the passive surveillance component. Active surveillance components contributed minimally (<0.2%) to the final probability of freedom. Sensitivity analysis showed that the probability of infected horses showing clinical signs was an important parameter influencing the system surveillance sensitivity. The monthly probability of disease introduction needed to be increased to 20% and greater to decrease the overall probability of freedom to below 90%. Current global standards require a 2-year post-incursion period of AHS freedom before re-evaluation of free zone status. Our findings show that the length of this period could be decreased if adequately sensitive surveillance is performed. In order to comply with international standards, active surveillance will remain a component of AHS surveillance in South Africa. Passive surveillance, however, can provide substantial evidence supporting AHS freedom status declarations, and further investment in this surveillance activity would be beneficial.

Establishing post-outbreak freedom from African horse sickness virus in South Africa's surveillance zone.

An African horse sickness (AHS) outbreak occurred in South Africa's AHS controlled area in autumn 2016. A freedom from disease survey was performed to establish the likelihood of ongoing circulation of the associated virus during the same period the following year. A single-stage surveillance strategy was employed with a population-level design prevalence of 1% to establish a survey population sensitivity of 95% (probability that one or more positive horses would be detected if AHS was present at a prevalence greater than or equal to the design prevalence). In March 2017, a total of 262 randomly selected horses from 51 herds were sampled from the 2016 outbreak containment zone. Three within-herd and herd-level design prevalence scenarios were used in evaluating the post-survey probability of freedom. Depending on the underlying design prevalence scenarios, effectively ranging between 0.8% and 6.4%, and the use of informed or uninformed priors, the probability of freedom derived from this surveillance ranged between 73.1% and 99.9% (uninformed prior) and between 96.6% and 100% (informed prior). Based on the results, the authors conclude that it is unlikely that the 2016 AHS virus was still circulating in the autumn of 2017 in the 2016 outbreak containment zone. The ability to perform freedom from disease surveys, and also to include risk-based methods, in the AHS controlled area of South Africa is influenced by the changing underlying population at risk and the high level of vaccination coverage in the horse population. Ongoing census post-outbreak must be undertaken to maintain a valid sampling frame for future surveillance activity. The seasonality of AHS, the restricted AHS vaccination period and the inability to easily differentiate infected from vaccinated animals by laboratory testing impact the ability to perform a freedom from disease survey for AHS in the 12 months following an outbreak in the controlled area.

A field investigation of an African horse sickness outbreak in the controlled area of South Africa in 2016.

An outbreak of African horse sickness (AHS) caused by AHS virus type 1 occurred within the South African AHS surveillance zone during April and May 2016. The index case was detected by a private veterinarian through passive surveillance. There were 21 cases in total, which is relatively low compared to case totals during prior AHS outbreaks in the same region (and of the same AHS virus type) in 2004, 2011 and 2014. The affected proportion of horses on affected properties was 0.07 (95% CI 0.04, 0.11). Weather conditions were conducive to high midge activity immediately prior to the outbreak but midge numbers decreased rapidly with the advent of winter. The outbreak was localized, with 18 of the 21 cases occurring within 8 km of the index property and the three remaining cases on two properties within 21 km of the index property, with direction of spread consistent with wind-borne dispersion of infected midges. Control measures included implementation of a containment zone with movement restrictions on equids. The outbreak was attributed to a reversion to virulence of a live attenuated vaccine used extensively in South Africa. Outbreaks in the AHS control zones have a major detrimental impact on the direct export of horses from South Africa, notably to the European Union.

The economic impact of Bluetongue and other orbiviruses in sub-Saharan Africa, with special reference to Southern Africa.

Bluetongue (BT) and African horse sickness (AHS) are considered the most important orbiviral diseases in Southern Africans countries. The general endemic status makes these diseases challenging to be quanti ed in terms of their economic impact. Using country reported data from BT and AHS outbreaks and cases, as well as international trade data, the economic impact of BT and AHS is evaluated on local, regional, and global scales. Local scale impact in the Southern African region is underestimated as shown by the underreporting of BT and AHS. Exceptions occur during epidemic cycles of the diseases and when the diseases impact regional animal movement and global trade, as in the case of AHS in South Africa. While BT is not directly implicated as a signi cant non-tari barrier for regional movement, there are unspeci ed clauses in import permits which refer to the 'OIE listed diseases' and the freedom thereof includes endemic diseases like BT. African horse sickness has a much more tangible regional and global economic impact because of movement restrictions within AHS control zones in South Africa and through international movement of horses from this country.