Viability of white spot syndrome virus (WSSV) in sediment during sun-drying (drainable pond) and under non-drainable pond conditions indicated by infectivity to shrimp

Kumar, Sujeet; Bharathi, R. Ananda; Rajan, J.J.S.; Alavandi, S.V.; Poornima, M.; Balasubramanian, C.; Ponniah, A. G.

doi:10.1016/j.aquaculture.2013.04.001

Cited by 31 publications

(16 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Before starting data collection, the questionnaire was tested using 20 farmers. Then, the questionnaire was discussed with local fisheries officers (n = 2) who performed the data collection.The identification of risk factors was based on a literature review , Corsin et al 2001, 2005, MPEDA/NACA 2003, Esparza-Leal et al 2009, Gao et al 2011, Tendencia et al 2011, Pradeep et al 2012, Kumar et al 2013, Reddy et al 2013, OIE 2014 and the field experiences of the present study's authors. Questions focused on 8 main issues that covered the disease status of the farm, potential risk factors, respondent's information, farm characteristics, farm environment, farm management, presence of the vector, and geographic information (Table 1).…”

mentioning

confidence: 99%

Risk factors associated with white spot syndrome virus outbreaks in marine shrimp farms in Rayong Province, Thailand

Yaemkasem

Boonyawiwat²,

Kasornchandra³

et al. 2017

Dis. Aquat. Org.

View full text Add to dashboard Cite

The purpose of this study was to determine risk factors for white spot disease (WSD) in Rayong, Thailand. A study was conducted from October 2014 to March 2015 to identify potential farm-level risk factors using a validated questionnaire. We completed 1 questionnaire for each farm; a total of 38 questionnaires from the case farms and 127 questionnaires from the control farms were collected. The results showed that the presence of WSD in previous crops and the use of seawater were risk factors (p < 0.01), indicating that the environment plays an important role in WSD outbreaks in Rayong. Good management practices for pond preparation and other mitigation steps should be part of a control measure program for WSD in this region.KEY WORDS: Shrimp ⋅ Epidemiology ⋅ Risk factors ⋅ White spot syndrome virus 124: 193-199, 2017 temperature and pH affected the shrimp and influenced WSD infection. Corsin et al. (2003) indicated that, in Karnataka, India, potential risk factors for WSSV included improper salinity in transportation bags, improper post-larvae (PL) length, and late stocking date. However, very little information is available about risk factors at the pond or farm level. Corsin et al. (2001) reported that the location of a pond close to the sea was a risk factor in Vietnam. In the Philippines, an important risk factor was feeding live mollusks to the shrimp (Tendencia et al. 2011). Recently, in Thailand, Piamsomboon et al. (2015) indicated that risk factors included the sourcing of water from communal canals, the use of year-round cultures, and an owner operating multiple farm sites. Resale or republication not permitted without written consent of the publisherDis Aquat OrgThe purpose of the present study was to identify farm-level risk factors for WSD in Rayong, Thailand. Results of this study will be used to improve or establish measures that can be used to prevent or control WSD in this area. This will reduce the economic losses of farmers in Rayong. In addition, conclusions from this study may also in struct disease evaluation and control in other geographical areas, both in side and outside Thailand. MATERIALS AND METHODS Target population and study frameworkAll active marine shrimp farms in Rayong were examined in this study. We selected this area because marine shrimp culture is predominant. Most of the farms in this area are located in 2 districts: the Mueang Rayoung District and the Klaeng District (Fig. 1). A study was conducted from October 2014 to March 2015 to identify potential among-farm (farmlevel) risk factors using a validated questionnaire. At the initiation stage of this study, the laboratory results from passive surveillance by the Department of Fisheries (DoF) of Thailand were used to categorize shrimp farms as either cases or controls. To qualify as a suspected farm for WSD, a farmer had to have called in a report to the local DoF and had to have brought at least 15 suspected shrimp to the laboratory. The following clinical signs were used to define the suspected cases and ide...

show abstract

mentioning

confidence: 99%

Risk factors associated with white spot syndrome virus outbreaks in marine shrimp farms in Rayong Province, Thailand

Yaemkasem

Boonyawiwat²,

Kasornchandra³

et al. 2017

Dis. Aquat. Org.

View full text Add to dashboard Cite

show abstract

“…White spot syndrome virus persisted for 1 year after a WSD outbreak in Vietnamese ponds 134 and for 10 months in pond soil stored at room temperature 155 . Moreover, WSSV remained viable for nearly 40 days in 30°C seawater in the absence of a host species, 156 for 19 days in sun‐dried sediment and for 35 days in waterlogged sediment 157 in which the viability of WSSV in the soil was affected by the type of soil 158 . In both latter studies, the decayed shrimp tissue in the sediment may have sustained the virus to persist for a reasonable time length in the pond sediment, despite the absence of known living vectors.…”

Section: Wssv Transmission At the Pond The Level And Interrelatedness...mentioning

confidence: 99%

White spot syndrome virus host range and impact on transmission

Desrina

Prayitno

Verdegem

et al. 2022

Reviews in Aquaculture

View full text Add to dashboard Cite

White spot syndrome virus (WSSV), the etiological agent of white spot disease (WSD), is a significant pathogen affecting shrimp farming industry worldwide. White spot syndrome virus is a generalist virus mainly infecting decapod crustaceans. The aims of this review were to: (1) Re-evaluate and update the status of reported WSSV host and vector species based on the methods used when detecting replication and transmission to shrimp and 2) make a critical evaluation of existing literature on the presence of WSSV in aquatic organisms and the potential role these organisms might play in the transmission of WSSV in pond systems and the wild. An evaluation of literature about WSSV reported host and vector species showed an increase from 33 families to 50 families including 11 families of non-crustacean hosts, proved the virus continues to spread beyond farmed shrimp and the shrimp pond environment.White spot syndrome virus transmission in the aquatic environment is complex as depicted in our model. Containment of WSSV in ponds and the natural environment is challenging, mainly because of its generalist nature and a lack of understanding about (1) WSSV transmission in the aquatic setting, (2) the route of WSSV transmission among species exist in the aquatic environment and (3) information on the transmission dynamics between WSSV in farmed crustaceans and non-farmed animals.

show abstract

“…Disease onset and mortality occur in shrimp quickly after exposure, with 90% of farmed stocks typically lost to disease within 2 d to 7 d [ 25 ] and nearly 100% mortality of experimentally infected shrimps observed after 5 d to 7 d [ 26 ]. Under laboratory conditions, WSSV has been shown to retain its infectivity in sea water for up 12 days and in sun dried and water-logged pond sediment for up to 19 and 35 days, respectively [ 27 ]. Through periodic sampling of seawater from abandoned shrimp culture ponds and surrounding canals in Vietnam, where previously an outbreak of WSD had led to 100% mortality of cultivated shrimp, the authors of [ 28 ] found that WSSV remained detectable for up to 20 months.…”

Section: Case Study: White Spot Disease In Penaeid Shrimpmentioning

confidence: 99%

“…As far as we know, there is no published estimate of this quantity for WSD among penaeids. We obtain a lower estimate of α L = 10 −4 ml virion −1 h −1 for Penaeus monodon , along with an upper estimate of the pathogen decay rate, ρ U = 0.005 h −1 , from the results of the WSSV viability in seawater experiment by Kumar, et al, ([ 27 ], details in Section C in S1 Appendix ). Lotz and Soto use a shrimp density of 12 animals per square metre of water surface in their experiment in order to mimic densities of wild populations [ 30 ].…”

Section: Case Study: White Spot Disease In Penaeid Shrimpmentioning

confidence: 99%

When and why direct transmission models can be used for environmentally persistent pathogens

et al. 2021

View full text Add to dashboard Cite

Variants of the susceptible-infected-removed (SIR) model of Kermack & McKendrick (1927) enjoy wide application in epidemiology, offering simple yet powerful inferential and predictive tools in the study of diverse infectious diseases across human, animal and plant populations. Direct transmission models (DTM) are a subset of these that treat the processes of disease transmission as comprising a series of discrete instantaneous events. Infections transmitted indirectly by persistent environmental pathogens, however, are examples where a DTM description might fail and are perhaps better described by models that comprise explicit environmental transmission routes, so-called environmental transmission models (ETM). In this paper we discuss the stochastic susceptible-exposed-infected-removed (SEIR) DTM and susceptible-exposed-infected-removed-pathogen (SEIR-P) ETM and we show that the former is the timescale separation limit of the latter, with ETM host-disease dynamics increasingly resembling those of a DTM when the pathogen’s characteristic timescale is shortened, relative to that of the host population. Using graphical posterior predictive checks (GPPC), we investigate the validity of the SEIR model when fitted to simulated SEIR-P host infection and removal times. Such analyses demonstrate how, in many cases, the SEIR model is robust to departure from direct transmission. Finally, we present a case study of white spot disease (WSD) in penaeid shrimp with rates of environmental transmission and pathogen decay (SEIR-P model parameters) estimated using published results of experiments. Using SEIR and SEIR-P simulations of a hypothetical WSD outbreak management scenario, we demonstrate how relative shortening of the pathogen timescale comes about in practice. With atttempts to remove diseased shrimp from the population every 24h, we see SEIR and SEIR-P model outputs closely conincide. However, when removals are 6-hourly, the two models’ mean outputs diverge, with distinct predictions of outbreak size and duration.

show abstract

Viability of white spot syndrome virus (WSSV) in sediment during sun-drying (drainable pond) and under non-drainable pond conditions indicated by infectivity to shrimp

Cited by 31 publications

References 25 publications

Risk factors associated with white spot syndrome virus outbreaks in marine shrimp farms in Rayong Province, Thailand

Risk factors associated with white spot syndrome virus outbreaks in marine shrimp farms in Rayong Province, Thailand

White spot syndrome virus host range and impact on transmission

When and why direct transmission models can be used for environmentally persistent pathogens

Contact Info

Product

Resources

About