Table 2.

Weekly direct and indirect contact rates among pig farms of four production types in Lira district, Uganda used for the simulation of PRRS virus spread.

Farm combination	Weekly direct contact by pig purchase	Weekly direct contact by boar sharing	Weekly direct contact (pig purchase and boar sharing)	Weekly indirect contact rates by equipment sharing only	Weekly indirect contact by scavenging alone	Weekly indirect contact rates (scavenging and equipment sharing)
Small to small	0.0192	0.0308	0.0501	0.6833	–	–
Small to scavenging	0.0192	0.0308	0.0501	0.6833	–	–
Small to medium	0.0192	0.022	0.0412	0.5	–	–
Small to large	0	0.024	0.024	0.3	–	–
Scavenging to small	0.0192	0.0308	0.0501	0.6833	–	–
Scavenging to scavenging	0.0192	0.0308	0.0501	0.6833	7	7.6833
Scavenging to medium	0.0192	0.022	0.0412	0.5	–	–
Scavenging to large	0	0.024	0.0240	0.3	–	–
Medium to small	0.0192	0.0247	0.0440	0.25	–	–
Medium to scavenging	0.0192	0.0247	0.0440	0.25	–	–
Medium to medium	0.0192	0.022	0.0412	0.5	–	–
Medium to large	0	0.0192	0.0192	0.25	–	–
Large to small	0.0192	0.0538	0.0731	3.75	–	–
Large to scavenging	0.0192	0.0538	0.0731	3.75	–	–
Large to medium	0.0192	0.0481	0.0673	0.25	–	–
Large to large	0.0192	0.0192	0.0385	0	–	–