Table 4. Summary results for scenarios 1, 2, and 3 including sample numbers and costs.
Summary results for scenario 4 include the prevalence that can be detected using common industry practices.
| Scenario | 1 | 2 | 3 | 4 |
|---|---|---|---|---|
| Short description of scenarios and objectives | Outbreak response, assess control area disease status every 5 days for up to a 97-day outbreak | Outbreak response, assess surveillance zone disease status every 21 days for up to a 97-day outbreak | Active national surveillance for early detection, sampling every 3 days for one year | Active national surveillance, sampling weekly for one year |
| Total sample size per premises | 720 up to 1,2601 | 72 up to 3151 | 4,392 to 7,6861 | 520 to 8322 |
| Pen-level prevalence that can be detected with 0.95 probability | 20% (by design) | 20% (by design) | 20% (by design) | 46 to 100%3 |
| Cost of total sample size per premises | $36,000 to $63,000 | $3,600 to $15,750 | $219,600 to $384,300 | $26,000 to $41,600 |
| Number of premises | 25 to 504 | 61 to 815 | 156 to 2405 | 2682 |
| Premises-level prevalence that can be detected with 0.95 probability | 1 in N (premises in control area) | 2% (by design) | 2% (by design) | 4.1% to 8.4%6 |
| Total sample size per scenario | Up to 18,000 to 63,000 | 4,392 up to 25,515 | 685,152 to 1,884,640 | 181,0002 |
| Cost of total sample size per scenario | $900,000 to $3,150,000 | $219,600 to $1,275,750 | $34,257,600 to $92,232,000 | $9,050,000 |
| Total cost including follow up costs for non-negative samples7 | $900,000 to $3,150,000 | $219,650 to $1,290,170 | $34,261,050 to $93,254,250 | $9,050,950 to $9,150,760 |
1 Range of samples represents the full range from previously outlined low and high sensitivity values and the sampling required over time to meet the scenario objectives.
2 Based on average number of rope samples submitted per premises (10 to 16) and average number of premises submitting to large swine veterinary diagnostic laboratories in the U.S.
3Assumes equal distribution of rope samples among 3 barns per premises and the full range of sensitivity values.
4 Sampling all premises in the control area.
5Alternatively, a lower level of sampling per farm and sampling more farms could give the same prevalence detection threshold at the premises level, but reduce prevalence detection threshold at the pen-level.
6Calculated assuming the among pen prevalence threshold that needs to be detected on each premises is 20% within a three day period to compare results to scenario 3.
7Sum of cost of total sample size per scenario for initial testing and range of total costs for follow up and confirmatory testing for initial samples with non-negative results