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Backyard production systems (BPS) are a common form of poultry and swine production worldwide. The limited implementation of biosecurity standards in these operations makes BPS a potential source for the emergence of pathogens that have an impact on both animal and public health. Information regarding circulation of influenza A virus (IAV) in poultry and swine raised in BPS is scarce; particularly in South American countries. The objective of this study was to estimate prevalence and seroprevalence of IAV in BPS in central Chile, identify subtype diversity, evaluate risk factors and spatial relative risk for IAV. Samples were collected from 329 BPS from central Chile. Seroprevalence at BPS level was 34.7% (95% CI: 23.1%–46.2%), 19.7% (95% CI: 9.9%–30.6%) and 11.7% (95% CI: 7.2%–16.4%), whereas prevalence at BPS level was 4.2% (95% CI: 0.0%–8.8%), 8.2% (95% CI: 0.8%–14.0%) and 9.2% (95% CI: 4.8%–13.1%), for the Metropolitan, Valparaiso and LGB O’Higgins regions, respectively. Spatial analysis revealed that central‐western area of Metropolitan region and the southern province of Valparaiso region could be considered as high‐risk areas for IAV (spatial relative risk = 2.2, p < .05). Logistic regression models identified the practice of breeding both poultry and pigs at the BPS as a risk factor (95% CI 1.06–3.75). From 75 IAV ELISA‐positive sera, 20 chicken sera had haemagglutination inhibition titres ranging from 20 to 160, and of these, 11 had microneutralization titres ranging from 40 to 960 for one or more IAV subtypes. Identified subtypes were H1, H3, H4, H9, H10 and H12. Results from this study highlight the need for further IAV surveillance programmes in BPS in Chile. Early detection of IAV strains circulating in backyard animals, especially in regions with large human populations, could have an enormous impact on animal and public health.

Specific locations of backyard production systems (BPSs) in Chile remain unclear, creating dificulties for designing surveillance activities for promptly detecting zoonotic agents with high impacts on health, such as avian influenza and Salmonella spp. This study aims to prove the use of spatial tools for improving the surveillance of BPSs in central Chile. A stratified and proportional random sampling was performed in 15 provinces of the Valparaiso, Libertador General Bernardo O'Higgins and Metropolitana regions. In this sampling, 329 BPSs were detected. In the first stage, 329 random sample points were allocated within the study area that searched for BPSs with poultry or swine breeding. Then, these random points were validated with remote sensing and in the field by searching for the presence of rural or semi-rural areas, nearby crops and houses or small towns within a 5 km radius around each point, while points allocated over hills or water sources (lakes or rivers) were discarded. Over 70 % of the sampling points were correctly allocated. In Los Andes, Cordillera and Chacabuco, less than 50 % of the points were allocated within feasible sampling areas. From the total BPSs sampled, 89 % met the 5 km radius criteria, and in the provinces of Valparaiso, Cordillera and Cachapoal, over 20 % of the sampling points were outside the radius criteria. This study is the first in Chile to explore the locations and sanitary statuses of BPSs. Given the lack of knowledge about the specific locations of BPSs, their identification during field activities represents a high cost for the surveillance of pathogens. We argue that using spatial tools in BPS surveillance design is an important support for healthcare management.

Objetivo. Verificar la presencia del virus de la enfermedad de Newcastle (ENC) en aves de sistemas productivos de traspatio (SPT) de parte de la zona central de Chile. Materiales y métodos. Entre 2013 y 2015, un total de 1,579 hisopados orotraqueales fueron colectados de gallinas, pavos, patos y gansos pertenecientes a 328 SPT de la zona central de Chile. En cada SPT, los hisopos colectados de aves de la misma especie fueron agrupados en el mismo tubo con medio de transporte formando un pool compuesto por no más de 5 muestras. Los pooles fueron analizados por RT-PCR a tiempo real. Resultados. De un total de 364 pooles, 6 resultaron positivos al virus de la ENC. Los pooles positivos correspondieron a gallinas de las regiones de Valparaíso (n = 1) y Libertador General Bernardo O’Higgins (n=5). Ningún pool correspondiente a pavos, patos o gansos fue diagnosticado positivo. Conclusiones. Los resultados positivos demuestran la presencia del virus de la ENC en SPT en Chile. Esto podría deberse a la circulación de cepas lentogénicas del virus transmitidas por aves silvestres o bien al contacto con cepas vacunales administradas en los planteles industriales cuyas aves vacunadas pueden finalizar como SPT.

ObjectiveThe purpose of this study was to detect the presence of circulatingSalmonellaspp. on backyard production systems (BPS) with poultryor swine breeding in central ChileIntroductionCharacteristics and conditions of backyard production systems(BPS) transform them into potential maintainers of priority zoonoticagents, likeSalmonellaspp., highly important agent because of itsimpact in animal and public health (1).MethodsA stratified and proportional random sampling approach wasperformed (2), based on 15 provinces from the study area (regions ofValparaiso, Metropolitana and LGB O’Higgins). 329 BPS sampled(equivalent to 1,744 samples). Stool content inoculated in test tubeswith peptone water (APT, Difco®) supplemented with Novobiocin(Sigma®), incubated for 18 to 24 hours at 37° C. Subcultured onmodify semisolid Rappaport Vassiliadis (MSRV, Oxoid®) agarsupplemented with Novobiocin, incubated for 24 to 48 hours at 41.5° C.Samples compatible with growth and/or diffusion were sub-culturedby exhaustion on Xylose Lysine Deoxychocolate (XLD, Difco®) agarand then incubated for 24 hours at 37° C (3). Confirmation made byconventional PCR forinvAgenes (4). Serotypes were predicted usinga combination of PCR and sequencing, aimed directly at genes codingfor O, H1 and H2 antigens (5).Results1,744 samples were collected belonging to the 329 BPS. 15 positiveBPS (4.6%) detected. Serotypes detected correspond toSalmonellaTyphimurium (21.7%), followed bySalmonellaEnteritidis (13.0%)andSalmonellaInfantis (13.0%),SalmonellaHadar or Istanbul(8.7%),Salmonella[z42] or Tenessee (4.4%),SalmonellaKentucky(4.4) and unknown (34.8%) (Table 1).ConclusionsThis is the first evidence of serotypes ofSalmonellaspp. circulatingat a regional level in BPS from central Chile. A relevant pathogen forpublic health.