Infectivity and Transmissibility of Acute Hepatopancreatic Necrosis Disease Associated Vibrio parahaemolyticus in Frozen Shrimp Archived at −80 °C

Abstract

Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus (VpAHPND) has been reported in commodity shrimp, but the potential risk of its global spread via frozen shrimp in the shrimp trade is yet to be fully explored. We hypothesized that frozen shrimp with AHPND could be a source of VpAHPND transmission; thus, the infectivity of frozen shrimp with AHPND was evaluated using a shrimp bioassay. To prepare infected frozen shrimp, 12 Penaeus vannamei (average weight, 2 g) were exposed to VpAHPND by immersion in water with a VpAHPND concentration of 1.55 × 107 CFU mL−1; once dead, the shrimp were stored at −80 °C for further analysis. After two weeks, a PCR assay was used to confirm AHPND positivity in frozen shrimp (n = 2), and VpAHPND was reisolated from the hepatopancreases of these shrimp. For the infectivity test, 10 P. vannamei (average weight, 4 g) were fed with the hepatopancreases of VpAHPND -infected frozen shrimp (n = 10). After feeding, 70% of the shrimp died within 118 h, and the presence of VpAHPND was confirmed using a PCR assay and histopathology examination; moreover, VpAHPND was successfully reisolated from the hepatopancreases of the dead shrimp. We are the first to evaluate the potential transmissibility of VpAHPND in frozen shrimp, and our results suggest that frozen shrimp with AHPND are a potential source of disease spreading between countries during international trade.

Hiệu quả của chất chiết cây giấm (Hibiscus sabdariffa L.) đối với hoạt tính kháng Vibrio parahaemolyticus, tăng trưởng và đáp ứng miễn dịch trên tôm thẻ chân trắng (Penaeus vannamei)

“…V. harveyi, V. campbellii, V. owensii và V. punensis cũng được cho là tác nhân gây bệnh AHPND vì các chủng vi khuẩn này đôi khi mang các gen độc tố có trình tự tương đồng với plasmid gây bệnh AHPND (Restrepo et al, 2018). Lee et al (2022) cho rằng tôm khỏe vẫn có khả năng nhiễm bệnh AHPND khi tiếp xúc với tôm nhiễm AHPND trước đó đã được trữ ở -80°C.…”