Semiquantitative Risk Evaluation Reveals Drivers of African Swine Fever Virus Transmission in Smallholder Pig Farms and Gaps in Biosecurity, Tanzania

Figure 3

Risk classification for African swine fever virus (hazard) among Tanzania’s smallholder pig farms, 2021. Mean agreement score ±standard deviation = 9.6 ± 0.7; median = 10 (1 = strongly disagree to 10 = strongly agreed). Kappa ± SE = 0.90 ± 0.10 (95% confidence interval: 0.88–0.92); the interrater agreement between foreign and local experts’ scores were calculated using the method of Landis and Koch [9]. Adapted from European centre for disease prevention and control. Operational guidance on rapid risk assessment methodology [21]. This figure was drawn based on the RRA questions in annex 7. Based on the focus group discussions and key informant interviews, the risk was particularly high among pregnant sows, adult female, shared adult boars, nonshared boars, porkers, growers and less among weaners and piglets in that order. In most cases, survivors are the young animals (piglets and weaners), and piglets may die due to cessation of milk when the sow dies.