Early Mortality Syndrome (EMS)/Acute Hepatopancreatic Necrosis Disease (AHPND) of Cultured Shrimps: Overview, Status and Updates

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1 Early Mortality Syndrome (EMS)/Acute Hepatopancreatic Necrosis Disease (AHPND) of Cultured Shrimps: Overview, Status and Updates Eduardo M. Leaño Coordinator, Aquatic Animal Health Programme Network of Aquaculture Centres in Asia-Pacific Bangkok, Thailand

2 What is EMS? Name for unusually heavy shrimp mortality approx. within the first 35 days of culture This was very imprecise case definition that has led to confusion in diagnosis prior to identification of the causative agent Many possible causes including diseases of well-known pathogens like WSSV & YHV Source: T Flegel

3 What is EMS? Dr. Lightner and his research team discovered a new pathology that explain many EMS outbreaks He provided a precise case definition which was a major breakthrough for further study Source: T Flegel

4 Causative agent: Vibrio Parahaemolyticus Disease renamed as: Acute hepatopancreatic necrosis disease (AHPND)

5 History of outbreaks First seen in China in latter part of 2009 (officially reported in 2010) and then in Vietnam in 2010 CHINA 2010 Next reported from Malaysia in 2011 Reported from Thailand (eastern Gulf of Thailand) in

6 History of outbreaks May 2013: Mexico

7 NACA Regional Response to EMS/AHPND

8 Recognizing the problem Alerting NACA Regional Advisory Group, OIE and FAO to the emerging threat of EMS in Mekong Delta of Vietnam in April 2011 NACA AG discussed the issue in AGM 10 in Nov 2011 in 10 th AGM Mangalore, India.

9 Alerting CA s Formal NACA circular to CA s of all member governments in May 2012 Development and wide dissemination of EMS/AHPNS Disease advisory in May 2012

10 Global Aquaculture Advocate; July/August 2012

11 Convening of Emergency Regional Consultation Convening of Asia Pacific emergency regional consultation (9-10 August 2012), Bangkok with support from DAFF, Australia 17 global shrimp experts 40 national delegates representing CA and lead research institutions 10 regional/international institutions; national universities 8 private sector representatives

12 Technical Report on AHPNS Technical report preparation and wider dissemination Latest updates and review of status Case definition at animal and pond level R&D directions Recommendations for national and regional levels

13 Disease Card Development and dissemination of AHPNS Disease Card To harmonize research effort To provide information to support disease surveillance To support outbreak investigations

14 Listing of AHPNS in QAAD AGM Nov 2012 Bangkok Prior to identification of the causative agent

15 Listing of AHPNS in QAAD Asia Regional Advisory Group on Aquatic Animal Health (AG): decided and agreed to include AHPNS in QAAD Reporting under the non-oie list of diseases for crustaceans; Purpose: gain more information about AHPNS within the region. 11 th AGM

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17 QAAD Report: 3Q 2013 Non OIE-listed diseases (Crustaceans) Acute hepatopnacreatic necrosis syndrome (AHPNS) July Aug Sept Australia *** *** *** Level of diagnosis China (2 nd quarter)?( ) II India Indonesia Iran *** *** *** Japan *** *** *** Korea, Republic of Lao PDR *** *** *** Malaysia I,II,III Philippines *** *** *** Nepal *** *** *** Singapore Sri Lanka *** *** *** Thailand (2 nd quarter) +( ) +( ) +( ) II Vietnam I,III *** No information available 0000 Never reported?( )Suspected but not confirmed in a zone +( ) Occurrence limited to certain zone

18 Follow-up Disease Advisory To address the many circulating false and baseless speculations on the effects and spread of AHPNS in the March 2013

19 AGM 12: Bangkok, Thailand November 2013 AHPNS was officially renamed as AHPND (based on recommendation from final report of FAO-TCP in Vietnam). Disease card was also recommended for revision to include ID of the pathogen, bioassay procedures, rapid diagnostic test, and other recent progress about the disease.

20 Gross and Histopathological Signs of AHPND (EMS)

21 Disease Signs at Pond/Farm Level Often pale to white hepatopancreas (HP) due to pigment loss in the connective tissue capsule. Significant atrophy (shrinkage) of HP. Often soft shells and guts with discontinuous contents or no content (empty gut). Black spots or streaks sometimes visible within the HP. HP does not squash easily between thumb & finger. Onset of clinical signs and mortality starting as early as 10 days post stocking. Moribund shrimp sink to bottom.

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24 8-10 days days Source : Mr. Chatree (shrimp culturist) همایش مرگ زودرس میگو پژوهشکده

25 Disease Signs at Animal Level (Histopathology) Acute progressive degeneration of the HP accompanied initially by a decrease of R, B and F-cells followed last by a marked reduction of mitotic activity in E-cells. Progress of lesion development is proximal-to-distal with dysfunction of R, B, F, and lastly E-cells, with affected HP tubule mucosal cells presenting prominent karyomegaly (enlarged nuclei), and rounding and sloughing into the HP tubule lumens. The sloughed HP cells provide a substrate for intense bacterial growth, resulting in massive secondary bacterial infection (putative Vibrio spp.) and complete destruction of HP at the terminal phase of the disease.

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27 Proximal-to-distal progression of lesion in the hepatopancreas. Source: DV Lightner همایش مرگ زودرس میگو پژوهشکده

28 Acute cell sloughing of HP tubular epithelial cells Source: L Tran همایش مرگ زودرس میگو پژوهشکده

29 Histopathology of Penaeus vannamei hepatopancreas from Thailand affected by AHPND. Source: T Flegel همایش مرگ زودرس میگو پژوهشکده

30 Terminal phase of AHPND showing heavy haemocytic infiltration and bacterial colonization. Source: L Tran همایش مرگ زودرس میگو پژوهشکده

31 Management and Prevention of AHPND Note: Succeeding slides are courtesy of (unless otherwise indicated) Dr. Loc Tran, one of the leading specialists on EMS/AHPND in the region; and Dr. Chalor Limsuwan, shrimp disease expert in the region.

32 Approaches to control EMS/AHPND Potential routes of infection: Horizontal transmission: waterborne, cannibalism, fecal-oral, biofilm, vectors, planktons, mollusk, birds, etc. Vertical transmission: Contaminated: broodstock, broodstock live feed, contaminated hatcheries => Contaminated larvae and postlarvae.

33 High risks leading to disease outbreaks Ponds with previous history of EMS/AHPND No water disinfection and/or imbalance pond ecology Lack of reservoir and biosecurity measures Contaminated postlarvae

34 Moderate risks leading to disease outbreaks Environmental factors: high temperature, intense sunlight, no algae, algal crash, thick algal bloom, eutrophication, bad feed management. Un-controlled bivalves, gastropods. Disease in adjacent ponds and in the area. Vectors: birds, crustaceans, aerosols

35 Risk management Sources of risk Hatcheries Shrimp farms Regions

36 Risk management! Hatcheries: Broodstock Broostock feed Hatchery biosecurity Testing of incoming broodstock and postlarvae before selling/stocking.

37 Risk management! Farms Farm design Reservoirs for incoming and discharged water Biosecurity Pathogen monitoring and management Pond/farm ecology Sustainability Shrimp health, gut flora health Chemotherapies

38 Risk management! Farming area/region/country Farming area planning Irrigation Regulations of: water discharge, water disinfection in affected ponds, water retention after disinfection. Community

39 Prevention 1. Use good healthy postlarvae( PL 10 or bigger) PL 10

40 PL12

41 Source: C Pitogo

42 Source: C Pitogo

43 M:G ratio

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45 Source : Mr. Chatree (shrimp culturist) همایش مرگ زودرس میگو پژوهشکده Lipid in hepatopancreas EMS Lipid in normal shrimp

46 Source: C Pitogo

47 Prevention(continue) 2. Use chemicals for water treatment ( eliminate viral and carrier) not over using probiotic during first month post-stocking 3. ph Alkalinity should be maintained not lower than 100 mg/l(ppm) 5. Maintain DO 4.0 mg/l all the time 6. Maintain consistence water color (phytoplankton)

48 Good water quality

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50 Some suggestions to prevent EMS/AHPND

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54 How to explain?

55 Source: P Sorgeloos

56 Expert Committee Meeting on Early Mortality Syndrome of Shrimp 26 March 2014, HCMC, Vietnam George Chamberlain Patrick Sorgeloos Indrani Karunasagar Victoria Alday Loc Tran Peter van Wyk Steven Newman Evan Sergeant (by Skype) Nguyen Van Hao Dr. Huang, Jie Dr. Stan Smith

57 Preliminary recommendations on prevention and control Antibiotics Not effective Antibiotic sensitivity tests show that EMS pathogen has already developed resistance to the full range of antibiotics

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59 Preliminary recommendations on prevention and control Zone management 1. Avoid siting of farms with shared inlet and discharge canals 2. Consider carrying capacity of ecosystem 3. Master plan aquaculture parks Diagnostics 1. Need local labs with ability to detect EMS with PCR and histology

60 Preliminary recommendations on prevention and control Breeding 1. Objective a. Need source of SPF broodstock b. Selectively breed for resistance to EMS 2. Technique a. Challenge SPF families with EMS pathogen and select those with best survival as parents of next generation b. Evaluate heritability of EMS resistance from one generation to the next

61 Preliminary recommendations on prevention and control Hatchery 1. Concern that maturation foods (marine worms, oysters) collected from the local environment may infect broodstock 2. Infected postlarvae can be sold unwittingly to farmers. Farms 1. Objective To eliminate EMS and other pathogens from water, establish balanced microbial population, stock with strong healthy postlarvae, and manage water and bottom quality.

62 Preliminary recommendations on prevention and control Disinfection a. Objective To eliminate multiple pathogens b. Techniques Chlorine or ozone

63 Preliminary recommendations on prevention and control Microbial management a. Objective To create mature microbial community ( Green water ) b. Techniques i. Tilapia to condition water ii. Probiotics to condition water iii. Maintain light to moderate biofloc iv. Avoid overfeeding and remove sludge v. Avoid booms and crashes of algae

64 Preliminary recommendations on prevention and control Nursery/Quarantine a. Objective To hold postlarvae from hatchery until they are larger, more robust, and confirmed EMS free b. Technique i. To hold postlarvae in raceways, tanks, netpens, etc. for days. ii. Evaluate health by PCR testing and growth and survival evaluation

65 Preliminary recommendations on prevention and control Biosecure intensive ponds a. Objective To cover the cost of additional biosecurity practices by intensifying production b. Techniques i. Small ponds ( ha) ii. Deep ( m) iii. Covered with plastic or birdnetting iv. More manageable disinfection, feeding, sludge control, water quality, biofloc v. High yields (30-50 mt/ha) cover extra investment in biosecurity

66 Preliminary recommendations on prevention and control Feed 1. Objective Identify feed additives that reduce EMS incidence 2. Techniques a. Chitosan b. Quorum sensing inhibitors c. Essential oils d. Immunostimulants

67 Emergency Response on EMS/AHPND: Thailand Case Study Note: Extracted from presentation of Jiraporn Kasornchandra, Janejit Kongkumnerd, Chutima Komvilai, Jaree Polchana, Department of Fisheries, Thailand

68 EMS/AHPND in Thailand History Disease similar to EMS/AHPND was first reported in shrimp farm located in the eastern Gulf of Thailand in late It was claimed that those farms used the same stock of PLs. In early 2012 (January-April), EMS/AHPND was reported in the east coast (Gulf of Thailand): Rayong, Chantaburi, Trad and Chachoengsao provinces.

69 EMS/AHPND in Thailand Rayong (Pra-sae) Chantaburi (Nayai-am) Trad Chachoengsao

70 EMS/AHPND in Thailand Current status: EMS/AHPND has been reported in 11 provinces (total 25 provinces) Central: Nakorn-platom Eastern: Rayong, Chantaburi, Trad and Chachoengsao Southern: Chumporn, Surattani, Nakorn-Sithumarat, Songkhla, Krabi and Phuket

71 Shrimp production of Thailand Annual production: 2011 : 502,188 ton 2012 : 473,230 ton Decrease 28,958 ton or 5.8 % Comparison of the shrimp production between the first three quarters of 2012 and (Jan Sep): 355,000 ton 2013 (Jan Sep): 189,000 ton Decrease 166,000 ton or 47 %

72 PL number (x million) همایش مرگ زودرس میگو پژوهشکده Possible factors that may influence the decreasing of shrimp production Reduction of PL stocking Total PL stocking Jan-Sep 2012: 60,000 million Jan-Sep 2013: 45,500 million PL stocking has decreased about 14,500 million or % due to insufficiency of PL quantity and shrimp farmers were not confident with EMS situation PL s tocking/ month in 2012 and Month

73 Possible factors that may influence the decrease of shrimp production Diseases and management system EMS/AHPND passive surveillance results (confirmed by histopathology described in NACA website). Month (2013) Total No. of cases No. of positive cases Jan Mar = 3.55 % Apr - Jun 1, = 1.83 %

74 Distribution of possible causes of shrimp illness under the situation of EMS/AHPND outbreak EMS/AHPND 3.4% EMS/AHPNS 3.40% April 2013 เมษายน 2556 เช อไวร ส Viral Disease 26.26% 26.3% EMS/AHPNS เช อไวร ส เช อแบคท เร ย อ น Other อ น 44.08% 44.0% Bacterial Disease เช อแบคท เร ย 26.3% 26.26%

75 EMS/AHPND in Thailand Technical update for EMS/AHPND 1. Causative agent: Suspected V. parahemolyticus has been isolated from PLs and affected shrimp with EMS/AHPND, and Koch s postulate has confirmed the cause.

76 EMS/AHPND in Thailand Technical update for EMS/AHPND 2. Epidemiology and risk factors study 2.1 Cross sectional study: emphasis in Rayong and Chantaburi provinces; - To identify risk factors associated with EMS/AHPND on farm and pond levels - To understand spreading pattern of EMS/AHPND in the area of study

77 EMS/AHPND in Thailand Risk factors at pond level: preliminary analysis 1. Source of PLs 2. Chlorine treatment before stocking 3. Feed quantity

78 EMS/AHPND in Thailand Technical update for EMS/AHPND 2. Epidemiology and risk factors study 2.2 Cohort study: - To confirm the potential risk factors associated with EMS/AHPND from previous study (by collecting systematic data from shrimp ponds in the affected areas) 3. Risk Management Measures will be applied to reduce EMS/AHPND

79 EMS/AHPND in Thailand The activities of concern in order to control EMS in shrimp farms and hatcheries: - shrimp farmer biosecurity training, - diagnostic procedures, - environmental and epidemiological studies, - national strategy, - farmer training, - emergency preparedness guidelines

80 EMS/AHPND in Thailand 1. EMS/AHPND is now being controlled under the Animal Epidemic Act at the national level 2. EMS/AHPND has been included in the National Surveillance Program disease distribution and zoning

81 EMS/AHPND in Thailand EMS/AHPND survey during February-May 2013 Month (2013) % Prevalence Provinces February 3.0 Chantaburi, Rayong, Chachoengsao, Songkhla, Surattani March 4.7 Chantaburi, Rayong,Trad, Songkhla, Surattani, Krabi April 3.4 Rayong, Trad, Chumporn, Songkhla, Surattani, Krabi May 3.5 Trad, Songkhla, Surattani, Nakorn- Sritumarat, Phuket

82 EMS/AHPND in Thailand DOF has launched a STOP EMS Program 1. Improvement of hatchery sanitation, broodstock management, quality of PLs 2. Screening shrimp pathogens including V. parahaemolyticus 3. Improvement of shrimp farm management 4. Control the use of antibiotics Food safety 5. For import quality assurance- both antibiotic residues and V. parahaemolyticus are subjected to test

83 Department of Fisheries; response to EMS/AHPND Action plans for mitigating the impact of EMS/AHPND 1. Setting up the local EMS/AHPND war rooms to advice, follow up and report the EMS/AHPND situation in each province, as well as the central EMS/AHPND war room to evaluate the disease situation and seek for mitigating measures for prevention (of spread) and control.

84 Action plans for mitigating the impact of EMS/AHPND 2. Surveillance and monitoring program - DoF has taken action on EMS/AHPNS surveillance and monitoring Program, action by assigned 26 Coastal Fisheries Research and Development Centers (CFRD centers) in 25 provinces - DoF has established a website < for registered users to submit reports on disease surveillance and observation - AHPNS is confirmed by histopathological techniques, describes in NACA website Month (2013) Total No. of cases No. of positive cases Jan Mar = 3.55 % Apr - Jun 1, = 1.83 %

85 EMS/AHPND in Thailand AquaThai Thai Aquatic Animal Disease Surveillance Information System This site provides access for registered users to the disease surveillance database. The system enables users to submit reports of disease observations and surveillance activities. It also supports disease zoning for export under OIE rules. This site contains: [Surveillance Database] - [Downloadable Resources] - [Image Library] - [Links]

86 Action plans for mitigating the impact of EMS/AHPND 3. Mitigation and management measures to lessen the EMS/AHPND Risk - Initiated in early 2013

87 Action plans for mitigating the impact of EMS/AHPND 3.1 Improvement of nursery sanitation - Inspection of nursery s sanitation; to maintain the facilities under the good sanitary conditions - PL health examination and quality testing by local DoF officers; according to the standard and quality testing of Pacific white shrimp for nurseries and grow-out facilities published by DoF

88 Action plans for mitigating the impact of EMS/AHPND 3.2 Improvement of nursery sanitation (cont.) - Examination of bacterial contamination in the system and in PL; shrimp nursery is required to provide the V. parahemolyticus test report and FMD for shrimp farmers on PL trade - Examination of WSSV, YHV, TSV, IHHNV, and IMNV in PL

89 Action plans for mitigating the impact of EMS/AHPND 3.2 Improvement of nursery sanitation (cont.) - Training on the on site screening of Total Vibrio and V. parahemolyticus in shrimp and water using microbiological technique

90 Action plans for mitigating the impact of EMS/AHPND 3.2 Improvement of shrimp farm management - The EMS restraining seminar for shrimp farmers was organized by DoF in 3 provinces; Songkhla, Phuket and Chantaburi - DoF notified the shrimp farm management guideline for preventing EMS outbreak to farmers - Farmers have opportunity to share their experiences

91 Action plans for mitigating the impact of EMS/AHPND 3.2 Improvement of shrimp farm management (cont.) - Provincial fishery officers and CFRDC officers visited shrimp farms for: - On site water quality monitoring - Shrimp health inspection, and if there is a risk of EMS/AHPNS, bacterial concentration in shrimp will also be investigated

92 Action plans for mitigating the impact of EMS/AHPND 3.2 Improvement of shrimp farm management (cont.) - CFRD centers provide services and supervise shrimp farmers on: - Bacteriological diagnostic for shrimp and pond water - Shrimp health examination before stocking and during culture, and shrimp health management - Disease diagnosis - Water quality analysis and management - Training on the on farm screening of Total Vibrio and V. parahemolyticus in shrimp and water using microbiological technique

93 Action plans for mitigating the impact of EMS/AHPND 3.2 Improvement of shrimp farm management (cont.) - DoF produces and promotes the use of Probiotic (DoF 1) for waste and water quality control and equilibrium of microorganisms in the culture environment

94 Action plans for mitigating the impact of EMS/AHPND 4. Measures for management and control of EMS/AHPND outbreak in shrimp farm - If the mortality of shrimp with unknown cause is noticed within 35 days after stocking, shrimp farmer must inform the DoF local officers within 24 hours, according to the Animal Epidemic Act (Article No. 8) - If the disease is confirmed, eradication procedure must be applied to prevent the spreading of the disease

95 Action plans for mitigating the impact of EMS/AHPND 5. Importation of Pacific white shrimp broodstock - Increase flexibility of the importation of the Pacific white shrimp broodstock - 15 days quarantine in the registered quarantine house is required - Particular viruses are also investigated - WSSV, YSV, TSV, IHHV, and IMNV

96 Action plans for mitigating the impact of EMS/AHPND 6. Ongoing research Study on epidemiology, causative factors and solution approaches of Early Mortality Syndrome (EMS) in marine shrimp in Thailand Measures on farm management to reduce risk factors associated with EMS/AHPND

97 Action plans for mitigating the impact of EMS/AHPND 7. Communication and public awareness 1. DoF has arranged several seminars in 2013 to enlighten the shrimp farmers on the EMS/AHPND information and situation 2. Provide leaflet, brochure, and guideline for farmers 3. Public awareness through media such as radio, TV, internet, and magazine

98 S hrimp production (ton) همایش مرگ زودرس میگو پژوهشکده PL number (8 million) Outcomes of the DoF response Shrimp production have a tendency to be increased from Jul-Sep 2013 onwards, and this can be attributed to: - Increasing of PL stocking which started in late March due to the farmers have confident in the resolution of DoF and the importation of quality broodstock - Improvement of farm management - Occurrence of disease is likely to be decreased PL s tocking in Month Shrimp production in Month

99 Countries Affected/Not Affected by EMS/AHPND: What to do???

100 Countries with EMS/AHPND Source: FAO, 2013

101 Countries with EMS/AHPND Source: FAO, 2013

102 Countries without EMS/AHPND Source: FAO, 2013

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