Baumberger Cecilia, Anríquez Gustavo, Galdames Pablo, Palma Tamara, Gonzalez María Antonieta, Orozco Katherinne, Oyarzun Cristobal, Rojas Camila, Marambio Victor, Ruiz Soledad, Di Pillo Francisca, Schultz-Cherry Stacey, Jimenez-Bluhm Pedro, Rushton Jonathan, Hamilton-West Christopher
Departamento de Medicina Preventiva, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago, Chile.
Programa de Doctorado en Ciencias Silvoagropecuarias y Veterinarias, Campus sur Universidad de Chile, Santiago, Chile.
Zoonoses Public Health. 2025 Feb;72(1):42-54. doi: 10.1111/zph.13182. Epub 2024 Sep 20.
Backyard production systems (BPS) represent an interface of contact between people, domestic and wild animals. Studies conducted in Chile during the last decade have provided extensive evidence of influenza A virus (IAV) circulation in backyard poultry and swine. The aim of this study was to investigate exposure practices of humans to animal-origin IAV within backyards.
Backyard farmers and household members of a total of 101 BPS in the proximity of wetlands located throughout Chile were interviewed between 2021 and 2022. Data were collected on the nature of human-animal contacts through participation in productive activities conducted within backyards, which was used to estimate participants' exposure risk to animal-origin IAV. Additionally, RT-qPCR and serologic IAV active surveillance was carried out in backyard animals. Multilinear regression was used to identify factors associated with exposure risk. Overall, IAV prevalence was 10.1% (95% CI: 4.7%-15.5%) and seroprevalence was 43.5% (95% CI: 29.7%-54.2%), both at the BPS level. Of 180 interviewees, 86% reported participating regularly in poultry or swine exposure activities within the backyard. A greater participation of male participants was observed when evaluating swine exposure activities, while female participation was greater for some activities related to poultry handling. Handwashing was a very extended hygiene practice; however, the use of personal protective equipment was uncommon. Different factors related to participants, households and backyards were associated with an increased exposure risk of participants to animal-origin IAV: (i) older age, (ii) less years of education, (iii) no off-farm work, (iv) greater backyard production value and (v) greater household consumption of backyard products.
These results indicate the circulation of IAV in BPS and the frequent human-animal contact at this interface, highlighting the need for awareness campaigns and educational programmes aimed at backyard farmers on prevention and biosecurity measures in the management of backyard animals.
后院生产系统（BPS）是人与家畜和野生动物接触的界面。过去十年在智利进行的研究提供了大量证据，证明甲型流感病毒（IAV）在后院家禽和猪中传播。本研究的目的是调查后院中人类接触动物源IAV的情况。
2021年至2022年期间，对智利各地湿地附近总共101个后院生产系统的后院养殖户和家庭成员进行了访谈。通过参与后院开展的生产活动收集了关于人畜接触性质的数据，用于估计参与者接触动物源IAV的风险。此外，还对后院动物进行了逆转录定量聚合酶链反应（RT-qPCR）和血清学IAV主动监测。采用多线性回归来确定与接触风险相关的因素。总体而言，在后院生产系统层面，IAV流行率为10.1%（95%置信区间：4.7%-15.5%），血清阳性率为43.5%（95%置信区间：29.7%-54.2%）。在180名受访者中，86%报告经常参与后院的家禽或猪接触活动。在评估猪接触活动时，男性参与者的参与度更高，而在一些与家禽处理相关的活动中，女性参与度更高。洗手是一种非常普遍的卫生习惯；然而，使用个人防护设备并不常见。与参与者、家庭和后院相关的不同因素与参与者接触动物源IAV的风险增加有关：（i）年龄较大，（ii）受教育年限较少，（iii）没有非农业工作，（iv）后院生产价值较高，（v）家庭对后院产品的消费量较大。
这些结果表明IAV在后院生产系统中传播，且在这个界面上存在频繁的人畜接触，突出了针对后院养殖户开展关于后院动物管理中的预防和生物安全措施的宣传活动和教育项目的必要性。
