Tweet
Transbound Emerg Dis
. 2022 Jun 23.
doi: 10.1111/tbed.14639. Online ahead of print.
Improved method for avian influenza virus isolation from environmental water samples
Ahmed Magdy Khalil 1 2 3 , Isshu Kojima 1 4 , Wataru Fukunaga 1 , Misuzu Okajima 1 5 , Sumire Mitarai 1 , Yoshikazu Fujimoto 1 4 6 , Tsutomu Matsui 7 , Masakazu Kuwahara 8 , Tatsunori Masatani 1 2 4 6 5 , Kosuke Okuya 1 4 6 , Makoto Ozawa 1 2 4 6 7
Affiliations
- PMID: 35737749
- DOI: 10.1111/tbed.14639
Abstract
Environmental water-targeted surveillance of migratory aquatic birds at overwintering sites is potentially one of the most effective approaches for understanding the ecology of avian influenza viruses (AIVs). In this study, we improved the method for AIV isolation from environmental water samples by making a minor modification to our previously reported process. We experimentally demonstrated that the AIV recovery efficiency of the modified method was 10-100-fold higher than that of the original method. This improved isolation method allowed us to isolate a considerably larger number of AIV isolates from environmental water samples collected at an overwintering site for tens of thousands of migratory aquatic birds in Japan during the 2018/19 winter season compared with those during previous winter seasons. Genetic and phylogenetic analyses revealed that AIVs of the same subtypes with multiple genetic constellations were circulating in a single overwintering site during a single winter season. These findings indicate that our improved isolation method contributes to enhance environmental water-targeted surveillance and to a better understanding of AIV ecology in migratory aquatic bird populations by monitoring ongoing AIV circulation. This article is protected by copyright. All rights reserved.
Keywords: avian influenza virus; environmental water; migratory aquatic birds; overwintering site; phylogenetic variations; virus isolation.