Interventions in live poultry markets for the control of avian influenza: A systematic review

Offeddu, Vittoria; Cowling, Benjamin J.; Peiris, J.S. Malik

In the same time frame, Yu and colleagues quantified the impact of closure and depopulation of 780 LPMs in four cities in Eastern China [29] . Their model was based on the assumption of constant but different pre-and post-intervention infection forces, which were estimated according to the illness onset time series of hospitalized H7N9-cases in each city. The model matched the observed incidence patterns with a posterior predictive value of 0.9 [29] . This analysis revealed a dramatic decline in H7N9-incidence in humans within 2-3 days from LPM closure, with very few case-onsets after the intervention (Table 3 ) [29] . This finding was consistent with a 97%-99% risk reduction of human infection following LPM-closure. A similar analysis using several different sources of epidemiologic data confirmed a N 90% reduction in H7N9-incidence following LPM closure in three of the four cities (p-values b 0.05) ( Table 3 ) [30] . According to a follow-up study, the effectiveness of LPM closure in the subsequent winter was 97% (95% CI = 89%-100%) [31] .