Multiple infections caused by white spot syndrome virus and Enterocytozoon hepatopenaei in pond‐reared Penaeus vannamei in India and multiplex PCR for their simultaneous detection

Abstract

White leg shrimp, Penaeus vannamei, were collected on a monthly basis from grow‐out ponds located at Tamil Nadu and Andhra Pradesh states along the east coast of India for screening of viral and other pathogens. Totally 240 shrimp samples randomly collected from 92 farms were screened for white spot syndrome virus (WSSV), infectious hypodermal and haematopoietic necrosis virus (IHHNV), infectious myonecrosis virus (IMNV) and Enterocytozoon hepatopenaei (EHP). The number of shrimp collected from shrimp farms ranged from 6 to 20 based on the body weight of the shrimp. All the shrimp collected from one farm were pooled together for screening for pathogens by PCR assay. Among the samples screened, 28 samples were WSSV‐positive, one positive for IHHNV and 30 samples positive for EHP. Among the positive samples, four samples were found to be positive for both WSSV and EHP, which indicated that the shrimp had multiple infections with WSSV and EHP. This is the first report on the occurrence of multiple infections caused by WSSV and EHP. Multiplex PCR (m‐PCR) protocol was standardized to detect both pathogens simultaneously in single reaction instead of carrying out separate PCR for both pathogens. Using m‐PCR assay, naturally infected shrimp samples collected from field showed two prominent bands of 615 and 510 bp for WSSV and EHP, respectively.

Co-Infection of Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV) and White Spot Syndrome Virus (WSSV) in the Wild Crustaceans of Andaman and Nicobar Archipelago, India

“…The incidences of viral diseases in aquaculture species, particularly crustaceans such as shrimps and crabs have been well studied [ 5 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ]. On the other hand, studies on viral infections in wild marine crustaceans are restricted to few reports [ 23 , 24 , 25 , 26 , 27 , 28 ].…”

In vitro propagation of infectious myonecrosis virus in C6/36 mosquito cell line

“…The presence of IMNV in the inoculum was confirmed by RT‐PCR using the IMNV‐specific primer set designed by Poulos and Lightner (2006). The homogenate was also tested for other shrimp pathogens such as white spot syndrome virus (WSSV), infectious hypodermal and haematopoietic necrosis virus (IHHNV) and Enterocytozoon hepatopenaei (EHP) by PCR, as multiple viral infections and EHP infection are common in India (Manivannan et al., 2002; Thamizhvanan et al., 2019). The filtrate was stored at −80°C for further analysis.…”

Rapid Detection of Enterocytozoon hepatopenaei Infection in Shrimp With a Real-Time Isothermal Recombinase Polymerase Amplification Assay

“…When infected, it causes stunted growth, soft shells, lethargy and white feces symptoms (Behera et al, 2019). In Asian countries including India, Thailand and China, EHP caused 10%-20% reduced production of shrimp annually leading to significant economic losses (Thamizhvanan et al, 2019). In the year 2015 in Jiangsu, China, EHP infections had caused 300 million CNY of loss for the shrimp farming industry.…”