Backyard productive systems (BPS) are recognized as the most common form of animal production in the world. However, BPS frequently exhibit inherent biosecurity deficiencies, and could play a major role in the epidemiology of animal diseases and zoonoses. The aim of this study was to determine if influenza A viruses (IAV) were prevalent in backyard poultry and swine BPS in central Chile. Through active surveillance in Valparaiso and Metropolitan regions from 2012 - 2014, we found that influenza virus positivity by real-time RT-PCR (qRT-PCR) ranged from 0% during winter 2012-45.8% during fall 2014 at the farm level. We also obtained an H12 hemagglutinin (HA) sequence of wild bird origin from a domestic Muscovy duck (Cairina moschata), indicating spillover from wild birds into backyard poultry populations. Furthermore, a one-year sampling effort in 113 BPS in the Libertador Bernardo O'Higgins (LGB ÓHiggins) region showed that 12.6% of poultry and 2.4% of swine were positive for IAV by enzyme-linked immunosorbent assay (ELISA), indicative of previous exposure of farm animals to IAV. This study highlights the need for improved IAV surveillance in backyard populations given the close interaction between domestic animals, wild birds and people in these farms, particularly in an understudied region, like South America.
Disease riskPhylogenetic analysisReal time RT-PCRSmall farmersZoonosisInfluenza A virusAnimalsAnimals, WildBirdsChileHumansInfluenza in BirdsInfluenza, HumanPoultry DiseasesZoonoses
Structured evidence records
Evidence records
6 total
Serological Evidence2 records
Serological EvidenceExtraction confidence 0.90
Key finding
Influenza A virus antibodies were detected by ELISA in poultry from backyard systems in central Chile, indicating prior exposure.
A one-year sampling effort in 113 BPS in the Libertador Bernardo O'Higgins region showed that 12.6% of poultry and 2.4% of swine were positive for IAV by enzyme-linked immunosorbent assay (ELISA), indicative of previous exposure of farm animals to IAV.
Method
ELISA
Sample type
serum
Serological EvidenceExtraction confidence 0.90
Key finding
Influenza A virus antibodies were detected by ELISA in swine from backyard systems in central Chile, indicating prior exposure.
A one-year sampling effort in 113 BPS in the Libertador Bernardo O'Higgins region showed that 12.6% of poultry and 2.4% of swine were positive for IAV by enzyme-linked immunosorbent assay (ELISA), indicative of previous exposure of farm animals to IAV.
Method
ELISA
Sample type
serum
Zoonotic Surveillance2 records
Zoonotic SurveillanceExtraction confidence 0.95
Key finding
Active and serological surveillance detected influenza A virus RNA and antibodies in backyard poultry and swine from central Chile.
Through active surveillance in Valparaiso and Metropolitan regions from 2012 - 2014, we found that influenza virus positivity by real-time RT-PCR (qRT-PCR) ranged from 0% during winter 2012-45.8% during fall 2014 at the farm level. Furthermore, a one-year sampling effort in 113 BPS in the Libertador Bernardo O'Higgins region showed that 12.6% of poultry and 2.4% of swine were positive for IAV by enzyme-linked immunosorbent assay (ELISA).
Detection of an H12 influenza A virus hemagglutinin sequence derived from wild birds in a domestic Muscovy duck indicates wildlife-to-domestic surveillance finding and spillover.
We also obtained an H12 hemagglutinin (HA) sequence of wild bird origin from a domestic Muscovy duck (Cairina moschata), indicating spillover from wild birds into backyard poultry populations.
Method
sequencing
Geographic raw
central Chile
Country inferred
Chile
Genomic Evolution1 records
Genomic EvolutionExtraction confidence 0.60
Key finding
An H12 hemagglutinin sequence analysis showed that the influenza A virus detected in a domestic Muscovy duck originated from wild birds, providing genomic evidence of avian-to-poultry spillover in Chile.
We also obtained an H12 hemagglutinin (HA) sequence of wild bird origin from a domestic Muscovy duck (Cairina moschata), indicating spillover from wild birds into backyard poultry populations.
Genes or proteins
H12 hemagglutinin (HA)
Analysis methods
sequence analysis; phylogenetic analysis
Spillover Event1 records
Spillover EventExtraction confidence 0.92
Key finding
Influenza A virus with an H12 HA sequence originating from wild birds was detected in a domestic Muscovy duck, confirming wild bird-to-poultry spillover in central Chile.
We obtained an H12 hemagglutinin (HA) sequence of wild bird origin from a domestic Muscovy duck (Cairina moschata), indicating spillover from wild birds into backyard poultry populations.
