This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.
This week, we studied a subset of MSHMP participants located in the Midwest to test if some location/time combinations are more prominent during certain seasons across the years. Data from 358 farms in 10 management systems from 2011 to 2015 was compiled to look for clusters.
The clusters found by the SaTScanTM software are represented below. The red circles represent clusters identified in the time period from January to June, whereas blue ones are July to December. We can note that clusters were identified every year but that they varied with time.

Key points
- PRRS cases are recognized to be seasonal and aggregated by geographical space.
- However, spatiotemporal patterns of PRRS clustering were not consistent across years.
- Drivers of infection spread may vary over the years.
Future uses for this model can be found in the entire report