Risk factors and spatial relative risk assessment for influenza A virus in poultry and swine in backyard production systems of central Chile

Abstract

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.

Antimicrobial Usage Factors and Resistance Profiles of Shiga Toxin-Producing Escherichia coli in Backyard Production Systems From Central Chile

“…A lack of understanding of the public health outcomes related to BPS antimicrobial usage in this neglected population, including both animal and humans ( 89 , 90 ), creates a perfect scenario for antibiotic misuse resulting in AMR generation on high impact pathogens ( 91 ). Recent reports highlights the use of AM in animal production under low and middle-income countries, a proxy to the BPS conditions, reporting that AM use was greatest in chickens, followed by swine, and dairy cattle, however, per kg of meat produced, AMU was highest in swine, followed by chickens and cattle ( 92 ), situation that could be similar under Chilean BPS conditions, if this neglected animal population was involved actively in surveillance programs of AMR or animal health ( 93 , 94 ).…”

A Systematic Review Analyzing the Prevalence and Circulation of Influenza Viruses in Swine Population Worldwide

“…The molecular detection approaches followed by sequencing are largely used for the research focusing on the influenza virus epidemiology [73,78,82,87,94,128,146,150]. [5,37,43,45,46,61,74,88,137,157,171,176,188,191,199,207,215,[219][220][221]241,243,248,250,263,289,290,301,306,307,326,334] IAV, IDV, H1N1, H1N2, H3N2, A(H1N1)pdm09 [45,192,227,282,285,287,302,322] 8. Blood/ serum IDEXX Ab test, ELISA, HI assay, NI assay, VN assay, MN assay, western blot, virus isolation (MDCK cells) H1N1, H1N2, H3N2, A(H1...…”

“…Interestingly, 7.9% chicken, 4.3% ducks and 11.1% geese samples collected from 329 BPS in Central Chile also had active IAV infections. The breeding practice of poultry and swine in the BPS was determined to be a major risk factor for IAV transmission [334].…”

Screening the Presence of Non-Typhoidal Salmonella in Different Animal Systems and the Assessment of Antimicrobial Resistance

“…The closed system category is composed of food production animals from eight industrial dairy farms (160 samples) [ 20 ] and 10 swine farms (182 samples), domestic animals from an equine veterinary hospital (545 samples) [ 21 ] and wild animals from three wildlife rehabilitation centers (405 samples) [ 19 ]. Samples were also obtained from animals living free-range outdoors, which were potentially being fed with unsafe remains of food, such as human waste [ 22 ]. The open-system category comprised samples obtained from 13 free-range dairy farms (260 samples), 329 backyard chicken farms (2188 samples), four sites of wetland birds (271 samples) and five other backyard animal sites (36 samples) ( Table 1 ).…”