The foot‐and‐mouth disease epidemic in Dumfries and Galloway, 2001. 2: Serosurveillance, and efficiency and effectiveness of control procedures after the national ban on animal movements

Abstract

After the foot-and-mouth disease (FMD) epidemic in Dumfries and Galloway in south-west Scotland in 2001, serosurveillance of sheep remaining in the 3 km radius Protection Zones around Infected Premises (IPS), and within a 10 km radius of IPS, revealed no evidence of infection. The epidemic was brought under control by a range of traditional techniques: slaughter of all animals on IPS and of veterinary-assessed Dangerous Contacts (DCS), movement restrictions, biosecurity, tracing of potential sources and spread of virus, and surveillance of At-Risk premises. Novel pre-emptive slaughter of FMD-susceptible animals on premises contiguous to IPS, and small ruminants and pigs on premises within 3 km of IPSs, commenced after the epidemic had peaked. Most of the traditional control procedures were undertaken quickly and with appropriate priority. Animals on IPS were usually slaughtered within one day of confirmation, and veterinary-assessed DCS within two days of confirmation of relevant IPS (a median of two days). The pre-emptive contiguous and 3 km culls took somewhat longer (medians of five and 17 days, respectively). IPS were most commonly identified as a result of reporting by farmers or their veterinarians (72 per cent of IPS); veterinary clinical patrols identified 16 per cent, while veterinary assessment of DCS and tracing each identified 5 per cent. No evidence of infection was found on any pre-emptively contiguously culled premises, and IPS were declared only on three 3 km cull premises. The time from estimated first lesion to end of slaughter on an IP was found, by regression analysis, to be a key component in effective control, manifested by a reduction in the estimated dissemination rate (EDR); there was little evidence that the intensity of contiguous culling affected the EDR. Patrols and serological surveillance of residual animals within 10 km of IPS, supported by more extensive evidence from elsewhere in the UK, suggested that cryptic infection in sheep was not widespread. Ultimately, there was insufficient evidence to support the effectiveness of 3 km pre-emptive culling as a control procedure.

Evaluation of Movement Restriction Zone Sizes in Controlling Classical Swine Fever Outbreaks

“…During the 1997–1998 CSF outbreaks in the Netherlands, seven million pigs were euthanized to alleviate adverse animal welfare outcomes, which competed for the limited resources going toward euthanizing infected pigs, carcass disposal, biosecurity, and disinfection. Consequently, the epidemic was prolonged, which might have caused additional animal welfare issues in pigs and economic losses (4, 34). A similar challenge of insufficient resources for euthanasia, carcass transport, and disposal was observed in the highly pathogenic avian influenza outbreaks in the United States in 2014, which also hindered the timely management of outbreaks (35).…”

Review: Evaluation of Foot-and-Mouth Disease Control Using Fault Tree Analysis

“…Incidents and accidents that affected the speed and degree of control during the 2001 outbreak of FMD in the UK were extracted from the six articles, and branches that were not relevant to the outbreak were pruned from the developed fault tree. Faults and failures stated in the peer‐reviewed papers (Ferguson et al., ; Davies, ; Thrusfield et al., ,b; McLaws et al., , ) were summarized into 12 basic events in the generic fault tree (Table ). Six of 12 events were related to administrative failures, indicating that there were substantial issues related to the analysis of the outbreak data, linking them to the appropriate control measures (Fig.…”

FMD and the contiguous cull

“…If only half the pre-emptive cull was superfluous, the direct cost would be £0·4 billion (culling, disposal and compensation at £250,000 per premises, for half the 3369 contiguous premises). Data in the paper by Thrusfield and others (2005b) suggest that fewer than 25 per cent of these premises were actually infected, in which case the cost would be higher. The recent NAO report ( NAO 2005) estimates that the epidemic cost DEFRA £3 billion, but the EFRAC om’s report acknowledges that the Government bore less than half the total cost and quotes the Institute of Directors estimate of around £10 billion, about 1 per cent of Gross Domestic Product.…”