Estimating Resource Requirements to Staff a Response to a Medium to Large Outbreak of Foot and Mouth Disease in Australia

Abstract

A recent report to the Australian Government identified concerns relating to Australia's capacity to respond to a medium to large outbreak of FMD. To assess the resources required, the AusSpread disease simulation model was used to develop a plausible outbreak scenario that included 62 infected premises in five different states at the time of detection, 28 days after the disease entered the first property in Victoria. Movements of infected animals and/or contaminated product/equipment led to smaller outbreaks in NSW, Queensland, South Australia and Tasmania. With unlimited staff resources, the outbreak was eradicated in 63 days with 54 infected premises and a 98% chance of eradication within 3 months. This unconstrained response was estimated to involve 2724 personnel. Unlimited personnel was considered unrealistic, and therefore, the course of the outbreak was modelled using three levels of staffing and the probability of achieving eradication within 3 or 6 months of introduction determined. Under the baseline staffing level, there was only a 16% probability that the outbreak would be eradicated within 3 months, and a 60% probability of eradication in 6 months. Deployment of an additional 60 personnel in the first 3 weeks of the response increased the likelihood of eradication in 3 months to 68%, and 100% in 6 months. Deployment of further personnel incrementally increased the likelihood of timely eradication and decreased the duration and size of the outbreak. Targeted use of vaccination in high-risk areas coupled with the baseline personnel resources increased the probability of eradication in 3 months to 74% and to 100% in 6 months. This required 25 vaccination teams commencing 12 days into the control program increasing to 50 vaccination teams 3 weeks later. Deploying an equal number of additional personnel to surveillance and infected premises operations was equally effective in reducing the outbreak size and duration.

Resource Estimations in Contingency Planning for Foot-and-Mouth Disease

“…The results of our estimations seem somewhat lower than what was estimated in Australia (17). Direct comparisons are difficult, due to geographical differences, resulting in several state disease control centers and local disease control centers in Australia, differences in estimated size of the epidemic, i.e., Garner et al chose a 90th percentile epidemic and differences in how results are presented.…”

“…This was also in line with what was found by Garner et al (17). This means that if veterinarians doing surveillance visits can be more efficient, the number of needed veterinarians will decrease substantially.…”

“…The plan includes personnel, equipment, and other physical resources.” Garner et al (17) estimated the needed resources during a hypothetical FMD-epidemic in Australia, focusing on the 90th percentile out of 100 iterations simulated to set-off from the area previously predicted to give the worst epidemics in terms of size and duration (18). For the Danish Veterinary and Food Administration, it is important to know how many persons must be available within hours and days in order to efficiently handle and eradicate the disease.…”

Early Decision Indicators for Foot-and-Mouth Disease Outbreaks in Non-Endemic Countries

“…These were applied according to each country’s FMD response plan (19, 26). Resources for disease control were based on each country’s estimates of expected resources (5). Each model run ended when disease was eradicated or after 1 year, whichever occurred first.…”

“…Modeling studies carried out in Australia (3–5) and overseas (6–8) have shown that vaccination is effective in reducing the duration and/or size of FMD outbreaks in situations where disease is widespread, where there is a high rate of spread or the resources for stamping out are limited. Reports suggest that early vaccination may have been beneficial in eradicating the disease earlier than was the case with recent FMD outbreaks in Korea (9) and Japan (10).…”