Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala, Guatemala.
Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Zoonoses Public Health. 2022 Nov;69(7):826-834. doi: 10.1111/zph.12972. Epub 2022 May 25.
Due to their documented epidemiological relevance as hosts for influenza A viruses (IAV), humans, poultry and pigs in backyard production systems (BPS) within wetlands could be key to the emergence of novel IAV variants able to transmit between humans or animals. To better understand the circulation of IAV at the human-animal interface of BPS within wetlands, we studied IAV in backyard duck flocks and pig herds in the Pacific Coast of Guatemala. From April 2013 to October 2014, we estimated the monthly IAV per cent seropositive and viral positive flocks and herds in two resource-limited communities. We detected antibodies in sera against the IAV nucleoprotein through ELISA. We also detected IAV viral RNA in respiratory (ducks and pigs) and cloacal (ducks) swabs through rRT-PCR directed at the matrix gene. We attempted viral isolation in eggs or MDCK cells followed by sequencing from swabs positive for IAV. During our study period, IAV seropositivity in duck flocks was 38%, and viral positivity was 23% (n = 86 BPS sampled). IAV seropositivity in pig herds was 42%, and viral positivity was 20% (n = 90 BPS sampled). Both flocks and herds had detectable antibodies against IAV mostly year-round, and IAV was detected in several months. We isolated an H3N2 virus from one pig sampled at the end of 2013. Standard nucleotide BLAST searches indicate that the isolated virus was similar to seasonal viruses circulating in humans, suggesting human-to-pig transmission. Our data show concurrent circulation of IAV in multiple species of poultry and pigs that were commingled in rudimentary conditions in proximity to humans, but no significant risk factors could be identified.
由于湿地后院生产系统（BPS）中的人类、家禽和猪被记录为流感病毒（IAV）的宿主，它们可能是新型 IAV 变种在人类或动物之间传播的关键。为了更好地了解 IAV 在湿地后院生产系统中人类-动物界面的循环情况，我们研究了危地马拉太平洋沿岸后院鸭群和猪群中的 IAV。从 2013 年 4 月到 2014 年 10 月，我们在两个资源有限的社区中估计了每月 IAV 血清阳性和病毒阳性的鸭群和猪群的比例。我们通过 ELISA 检测血清中针对 IAV 核蛋白的抗体。我们还通过针对基质基因的 rRT-PCR 检测呼吸道（鸭和猪）和泄殖腔（鸭）拭子中的 IAV 病毒 RNA。我们尝试从 IAV 阳性拭子中在鸡蛋或 MDCK 细胞中进行病毒分离，然后进行测序。在我们的研究期间，鸭群的 IAV 血清阳性率为 38%，病毒阳性率为 23%（n=86 个后院 BPS 采样）。猪群的 IAV 血清阳性率为 42%，病毒阳性率为 20%（n=90 个后院 BPS 采样）。鸭群和猪群全年都有针对 IAV 的可检测抗体，并且在几个月内都检测到了 IAV。我们从 2013 年底采集的一头猪中分离出一株 H3N2 病毒。标准核苷酸 BLAST 搜索表明，分离出的病毒与在人类中流行的季节性病毒相似，提示存在人传猪的情况。我们的数据显示，多种家禽和猪在简陋的条件下混养，同时在这些动物中循环 IAV，但没有发现明显的风险因素。
