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In South Vietnam, live bird markets (LBMs) are key in the value chain of poultry products and spread of avian influenza virus (AIV) although they may not be the sole determinant of AIV prevalence. For this reason, a risk analysis of AIV prevalence was conducted accounting for all value chain factors. A cross-sectional study of poultry flock managers and poultry on backyard farms, commercial (high biosecurity) farms, LBMs and poultry delivery stations (PDSs) in four districts of Vinh Long province was conducted between December 2016 and August 2017. A total of 3597 swab samples were collected from birds from 101 backyard farms, 50 commercial farms, 58 sellers in LBMs and 19 traders in PDSs. Swab samples were submitted for AIV isolation. At the same time a questionnaire was administered to flock managers asking them to provide details of their knowledge, attitude and practices related to avian influenza. Multiple correspondence analysis and a mixed-effects multivariable logistic regression model were developed to identify enterprise and flock manager characteristics that increased the risk of AIV positivity. A total of 274 birds were positive for AIV isolation, returning an estimated true prevalence of 7.6% [95% confidence interval (CI): 6.8%-8.5%]. The odds of a bird being AIV positive if it was from an LBM or PDS were 45 (95% CI: 3.4-590) and 25 (95% CI: 1.4-460), respectively, times higher to the odds of a bird from a commercial poultry farm being AIV positive. The odds of birds being AIV positive for respondents with a mixed (uncertain or inconsistent) level and a low level of knowledge about AI were 5.0 (95% CI: 0.20-130) and 3.5 (95% CI: 0.2-62), respectively, times higher to the odd of birds being positive for respondents with a good knowledge of AI. LBMs and PDSs should receive specific emphasis in AI control programs in Vietnam. Our findings provide evidence to support the hypothesis that incomplete respondent knowledge of AI and AIV spread mechanism were associated with an increased risk of AIV positivity. Delivery of education programs specifically designed for those in each enterprise will assist in this regard. The timing and frequency of delivery of education programs are likely to be important if the turnover of those working in LBMs and PDSs is high., (© 2021 Wiley-VCH GmbH.)

The spread of African swine fever (ASF) has reached pandemic levels over the last decade, and outbreaks of this disease in China, Mongolia, Vietnam and Cambodia in 2018 and 2019 could accelerate its transmission to neighbouring Asian territories. Thus, the risk that the ASF virus (ASFV) will be introduced to disease-free territories increases each year. Since Japan is an island nation, the most likely way in which ASFV would be introduced is via pork products brought in air passengers' luggage (PPAP). Therefore, in the present study, we assessed the risk of ASFV introduction to Japan via PPAP. For the purposes of this analysis, we considered 214 international commercial flights travelling from 47 origin territories to 31 destination airports as potential routes of ASFV introduction via PPAP. The risk was estimated quantitatively through a stochastic model that considered the volume of air passengers' luggage, the amount of confiscated pork products that were carried in air passengers' luggage and the disease status of the origin territory. The overall mean annual probability of ASFV introduction to Japan via PPAP was found to be 0.941 [95% confidence interval (CI), 0.661-1.000], which approximately corresponds to one introduction every 1.06 years. At the origin territory level, Mongolia was led as the highest risk territory, with a risk of 0.864 (95% CI, 0.434-1.000), followed by China (0.697; 0.223-0.999), Vietnam (0.662; 0.196-0.998) and the Russian Federation (0.136; 0.018-0.401). At the destination airport level, Narita International Airport had the highest risk (0.905; 0.537-1.000), followed by Kansai International Airport (0.496; 0.109-0.961), Tokyo International Airport (0.389; 0.072-0.879) and Chubu Centrair International Airport (0.338; 0.058-0.816). This information will help improve risk management activities and monitoring systems to prevent the introduction of ASFV to Japan., (© 2019 Blackwell Verlag GmbH.)