Hassan Mohammad M, El Zowalaty Mohamed E, Islam Ariful, Khan Shahneaz A, Rahman Md K, Järhult Josef D, Hoque Md A
Faculty of Veterinary Medicine, Chattogram Veterinary and Animal Sciences University, Chattogram 4225, Bangladesh.
Department of Medical Biochemistry and Microbiology, Zoonosis Science Center, Uppsala University, SE-75 123 Uppsala, Sweden.
Vet Sci. 2020 Jun 1;7(2):73. doi: 10.3390/vetsci7020073.
Highly pathogenic avian influenza H5 viruses have pandemic potential, cause significant economic losses and are of veterinary and public health concerns. This study aimed to investigate the distribution and diversity of hemagglutinin (HA) subtypes of avian influenza virus (AIV) in poultry and wild birds in Bangladesh. We conducted an avian influenza sero-surveillance in wild and domestic birds in wetlands of Chattogram and Sylhet in the winter seasons 2012-2014. We tested serum samples using a competitive enzyme-linked immunosorbent assay (c-ELISA), and randomly selected positive serum samples (170 of 942) were tested using hemagglutination inhibition (HI) to detect antibodies against the 16 different HA sero-subtypes. All AIV sero-subtypes except H7, H11, H14 and H15 were identified in the present study, with H5 and H9 dominating over other subtypes, regardless of the bird species. The diversity of HA sero-subtypes within groups ranged from 3 (in household chickens) to 10 (in migratory birds). The prevalence of the H5 sero-subtype was 76.3% (29/38) in nomadic ducks, 71.4% (5/7) in household chicken, 66.7% (24/36) in resident wild birds, 65.9% (27/41) in migratory birds and 61.7% (29/47) in household ducks. Moreover, the H9 sero-subtype was common in migratory birds (56%; 23/41), followed by 38.3% (18/47) in household ducks, 36.8% (14/38) in nomadic ducks, 30.6% (11/66) in resident wild birds and 28.5% (2/7) in household chickens. H1, H4 and H6 sero-subtypes were the most common sero-subtypes (80%; 8/10, 70%; 7/10 and 70%; 7/10, respectively) in migratory birds in 2012, H9 in resident wild birds (83.3%; 5/6) and H2 in nomadic ducks (73.9%; 17/23) in 2013, and the H5 sero-subtype in all types of birds (50% to 100%) in 2014. The present study demonstrates that a high diversity of HA subtypes circulated in diverse bird species in Bangladesh, and this broad range of AIV hosts may increase the probability of AIVs' reassortment and may enhance the emergence of novel AIV strains. A continued surveillance for AIV at targeted domestic-wild bird interfaces is recommended to understand the ecology and evolution of AIVs.
高致病性禽流感H5病毒具有大流行潜力，会造成重大经济损失，且关乎兽医和公共卫生领域。本研究旨在调查孟加拉国家禽和野鸟中禽流感病毒（AIV）血凝素（HA）亚型的分布及多样性。我们在2012 - 2014年冬季对吉大港和锡尔赫特湿地的野生和家养鸟类进行了禽流感血清监测。我们使用竞争酶联免疫吸附测定（c - ELISA）检测血清样本，并对随机选取的阳性血清样本（942份中的170份）进行血凝抑制（HI）试验，以检测针对16种不同HA血清亚型的抗体。本研究鉴定出了除H7、H11、H14和H15之外的所有AIV血清亚型，无论鸟类种类如何，H5和H9在其他亚型中占主导地位。组内HA血清亚型的多样性范围从3种（家鸡中）到10种（候鸟中）。H5血清亚型在游牧鸭中的流行率为76.3%（29/38），在家鸡中为71.4%（5/7），在留鸟中为66.7%（24/36），在候鸟中为65.9%（27/41），在家养鸭中为61.7%（29/47）。此外，H9血清亚型在候鸟中很常见（56%；23/41），其次是家养鸭中的38.3%（18/47），游牧鸭中的36.8%（14/38），留鸟中的30.6%（11/66），家鸡中的28.5%（2/7）。H1、H4和H6血清亚型是2012年候鸟中最常见的血清亚型（分别为80%；8/10、70%；7/10和70%；7/10），2013年是留鸟中的H9（83.3%；5/6）和游牧鸭中的H2（73.9%；17/23），2014年是所有鸟类中的H5血清亚型（50%至100%）。本研究表明，孟加拉国不同鸟类中HA亚型具有高度多样性，这种广泛的AIV宿主范围可能会增加AIV重配的概率，并可能促进新型AIV毒株的出现。建议在目标家养 - 野生鸟类界面持续监测AIV，以了解AIV的生态学和进化情况。
