Blowfly strike in sheep: self-help surveillance for shepherds is unsustainable

Flystrike in sheep, mostly caused by Lucilia sericata (Diptera: Calliphoridae), has been consistently identified as one of the most important sheep diseases from both a financial and welfare perspective (Bennett and others 1999, Bennett 2003, Bennett and Ijpelaar 2005, Boyne and others 2006). Infestation levels vary greatly depending on a wide range of factors related to the composition of the parasite fauna, the host, animal husbandry and control practices, climate and geography. However, it has been predicted that the season for flystrike will change (Wall and others 2011), which, anecdotally, appears to be the case (Anon 2012). Variation in the occurrence of flystrike in sheep, from year to year and area to area (Bisdorff and others 2006), means that traditional preventative programmes are often not as effective as they used to be. A report in 2013, commissioned by the pharmaceutical industry (Wall and others 2013), identified three key issues experienced by farmers: unpredictable weather patterns that make the timing of blowfly treatment difficult, increased risk of treatment resistance and the problem of treating parasites too late in the season. Early use of appropriate compounds for the prevention of flystrike aids effective control (Walters and Wall 2012). With the aim to help farmers tailor their flystrike control programmes, a simple website was developed (http://www.flystrikealert.co.uk/). The objective was for British farmers to be able to anonymously report when they encountered cases of flystrike in their flock. The basic details to be submitted are date of detection; location to postcode district level (first four characters); age group (lamb, ie, <1 year lamb; mature sheep >1 year) and severity level (minor <25 per cent of flock; major >25 per cent flock). To avoid spurious usage, the CPH (County, Parish, Holding) number has to be entered for a record to be validated, although this …