Jie Huang, DG, Network of Aquaculture Centres in Asia-Pacific (NACA), in a special interview to Pravash Pradhan, Chief Editor, aquapost.in and SMRT AGRIPOST, talks about the current COVID 19 pandemic and its impact on the aquaculture value chain, the need for developing strong domestic market and the stringent biosecurity measures to prevent the spread of glass post-larvae (Glass PL) in shrimp hatcheries.
Q. What is the impact of COVID 19 on aquaculture? How long will the crisis continue?
Ans: The impact of COVID-19 on aquaculture has been seen in the full value chain. During the epidemic period, the social distance requirement and shutdown of markets significantly affected the marketing of aquaculture products. As restaurants, gatherings, meetings, and festivals are closed, it has caused significant losses to the aquatic products markets.
Aquaculture products face severe backlogs. The prices of aquatic products have fallen sharply. The supply chains for aquaculture related commodities, such as seed, feed, and additives, were also disrupted.
Limited mobility also caused difficulty in the industry. Aquaculture related services such as diagnosis, consultation, and customer services, etc., have also become hard to access.
The shortage of laborers for aquaculture farming was seen due to movement limitations. Job opportunities in aquaculture have also declined dramatically. Women lose their jobs as the factories of aquatic processing are closed. The trade of farmed aquatic animals, such as several species of amphibians, has been banned because of changes in wildlife regulations.
After some countries have contained the outbreak of COVID-19, the aquaculture industry experienced complex fluctuations. The prices of aquatic products have rebounded rapidly due to the rising demand in the aquatic markets and the lag in production and supply chain. The low tide of production may continue due to the earlier decline in seedling, feed, and other services.
The risk of aquatic diseases is also on the rise due to the hasty recovery and rapid growth of aquaculture production following the containment of COVID-19 outbreak, with the early absence of diagnostic services or inadequate biosecurity measures.
Due to the spread of COVID-19 among countries and the outbreak of the pandemic in different periods, the international trade of aquatic products continues to suffer. If the outbreak crisis threatens food security and causes food exporters to restrict soybean exports, the production of aquatic feed will fall short, leading to higher prices.
This situation will further lead to higher prices of aquatic products, contraction of markets, and narrowed profit margins. The economies and employment that are primarily dependent on international trade in aquatic products will be significantly affected. The national economy and trade have to depend more on domestic consumption. Investments in the aquaculture value chains may continue to decline after months of the control of the outbreak of COVID-19.
Q. What are the advisories you have sent to the member countries to tackle the crisis?
Ans: When COVID-19 was at the beginning of the outbreak, we searched for some research advances related to SARS-CoV and actively followed up with new findings of 2019-nCoV. We drafted two recommendation articles, titled “Drafted Approach on Assessment of Risk Exposure Events for 2019-novel Coronavirus” and “Importance and Feasibility of Early Self-intervention after Infection with 2019-novel Coronavirus”, which were sent to China and Thailand governments.
With my background in virology, I reviewed publications and the newest progress in 2019-nCoV. I found out that there have been numbers of natural components of plant origin reported to have the activity to inhibit SARS-CoV or 2019-nCoV in vitro. The conclusion was focused on the two most common components with good effectiveness and safety, including hesperetin from citrus peel and epigallocatechin gallate (EGCG) from green tea.
Researchers reported that the activity of hesperetin to inhibit 3CLpro protease of SARS-CoV and the activity of EGCG to block the binding of S protein of 2019-nCoV to cellular receptor ACE2, respectively. Recommendations were made to people in member countries or organizations for the case that someone gets high exposure to an infected person or a suspect case, and the hospital treatment is not accessible before the infection is detected. I suggested using early self-medication by in-taking orange peels and green tea at home to prevent the virus during early infection. This approach can provide great help to those workers in the aquaculture sector in preventing the development of infection after exposure risk during the pandemic of COVID-19.
For the aquaculture sector, we provided our opinions for the queries from Chinese government and media about if aquatic animals have any risks in the spread of COVID-19. Based on the knowledge in virology and international standards, it has been concluded that no aquatic animal, including finfishes, crustaceans, molluscs, amphibians, and reptiles, etc., has the risk to be infected with any coronavirus.
The risk of COVID-19 transmission via aquatic products is generally negligible or controllable. Recently, we participated in a group to discuss and draft a review “Viewpoint: SARS-CoV-2 (the cause of COVID-19 in humans) is not known to infect aquatic food animals nor contaminate their products”. The review paper has been published in the recent journal Asian Fisheries Science and attracts wild attention.
Considering the crisis impacts on the Members, NACA, as one of the co-organizers, was involved in the discussions with the Food and Agriculture Organization (FAO) and the local organizer of China. We expressed our concerns and the suggestion of delaying the Global Conference on Aquaculture Millennium + 20 (GCA2020). Currently, the FAO, NACA, and the Ministry of Agriculture and Rural Affairs of China have agreed to postpone GCA2020, which was scheduled to be held on 26 October 2020, to next year. The International Organization Committee of GCA2020 has accepted this decision. Since the NACA Governing Council Meeting (GCM) was initially scheduled to be held back-to-back with GCA2020, the Secretariat considered several options for a change to the GCM, which will be proposed for the discussion and decision of the Governing Council Members.
Q. Has NACA made any study about the losses accrued by the member countries and sent any recommendation?
Ans: Currently, there is no available data for the estimation of the economic loss accrued by the Members. We encourage the Members to communicate with the Secretariat on this issue. The Secretariat is considering discussing the relevant issues in the 13th Technical Advisory Committee Meeting.
Q. A new virus, Decapod Iridescent Virus 1 (DIV1), has been detected in the south of Guangdong Province of China. Could you please elaborate on the disease and the emerging threat? How will it impact the shrimp industry?
Ans: On 21 April, NACA published an information report: “Disease advisory: Decapod Iridescent Virus 1 (DIV1): An emerging threat to the shrimp industry” on the NACA website
(https://enaca.org/?id=1098&title=decapod-iridescent-virus-1-an-emerging-threat-to-the-shrimp-industry) This information report describes the history, known host range, clinical signs, molecular diagnostic methods, and prevention strategies for decapod iridescent virus 1 (DIV1).
Two Chinese groups independently reported the virus identified from samples collected in 2014. They named the virus as Cherax quadricarinatus iridovirus (CQIV) from redclaw crayfish Cherax quadricarinatus and Shrimp hemocyte iridescent virus (SHIV) from white leg shrimp Penaeus vannamei, respectively. China’s government extended the National Target Surveillance Program for Aquatic Animal Diseases to cover DIV1 in 2017. The results of the surveillance program were published in the annual official report China Aquatic Animal Health. Relevant research papers on DIV1 or its earlier strains SHIV and CQIV were also published in international journals.
NACA has listed the disease as an important regional disease in the disease list for the Quarterly Aquatic Animal Disease Report (QAAD) since the end of 2016. The main threatened species include P. vannamei, Macrobrachium rosenbergii, and Procambarus clarkii, etc. The pathogenicity of DIV1 to P. vannamei may be weaker than that of white spot syndrome virus (WSSV), as the half lethal time (LT50) of DIV1 by oral administration challenge is about 8 days, which was more than double of that of WSSV. However, unlike WSSV, it can cause high mortality in M. rosenbergii. The gross sign of a white spot under the base of the rostrum in infected M. rosenbergii can be a typical diagnostic feature for the disease.
According to the results from the surveillance program and epidemiological investigation, it’s estimated that DIV1 may cause about 15%~17% of the total loss of farmed P. vannamei. Notably, NACA published an urgent warning indicated by Thai scientists that the virus has been detected in the wild P. monodon samples collected in the Indian Ocean on 25 February (https://enaca.org/?id=1093&title=urgent-warning-pcr-positive-imnv-and-div1-in-wild-penaeus-monodon-from-indian-ocean). Relevant recommendations have also been provided in the urgent warning.
Q.. Is NACA working on to develop any medicine about DIV1 and advisory?
Ans: The NACA Secretariat encourages the Lead Centers, the Regional Resource Centers for Aquatic Animal Health, Regional Reference Laboratories, Regional Resource Experts, and other Participating Centres of NACA and the Members to take early concern on the investigation of epidemiology and development of biosecurity measures to prevent the risk of DIV1.
Besides the abovementioned disease advisory and urgent warning, the Secretariat also arranged a disease card which was edited by relevant experts and commented by the Advisory Group for Aquatic Animal Health (AG) of NACA. The disease card is almost on the final edition and will be released soon. It is intended to provide diagnostic methods and reporting instructions for the Members for the early detection and the QAAD report of the disease. Additionally, NACA was also involved in the edition of an FAO Information Sheet Decapod Iridescent Virus 1 and provided relevant information.
Q. What type of measures should Indian shrimp hatchery operators adopt to protect against Glass post-larvae after it was reported in China?
Ans: Currently, the causative agent of glass post larvae is not reported. The phenomena reported in early April in some areas of Guangdong and Guangxi Provinces of China. Affected postlarva shows a transparent body, empty stomach and gut, and atrophic hepatopancreas at 2-3 days post-stocking of P5.
There are some suspicions on a new bacterial or viral causative agent, as the known pathogens are not detectable but with a high loading of bacteria. There are also some arguments that it may be due to abnormal weather or water quality issues. The reported phenomena may not be the same, as there is no definition to identify the phenomena. Scientists in the China Agriculture Research System for Crustaceans were immediately involved in the investigation due to the close relationship between scientists and farmers.
NACA Secretariat encourages the Members to report any occurrences of cases with immediate notification. Translation of national news to inform the Secretariat will also help the exchange of knowledge for early response. If cases found in a hatchery, current recommendations can be general biosecurity-based measures. The measures recommended include immediate reporting of cases, sampling of affected populations and original broodstocks, diagnostic examinations of affected animals with clinical and pathological signs and molecular tests, quarantine or elimination of the affected populations with separation and disinfectant, disinfection of water and hatchery, fallow of relevant facilities or hatchery, tracking of risks and examination of SOP and its implementation, and training of employees, etc.
Q. What are the initiatives taken by NACA to strengthen the aquaculture sector in the Asia-Pacific region?
Ans: The occurrence of COVID-19 has hindered the regional communication and cooperation of the aquaculture sector in all aspects, including market, trade, production, research, training, education, and governance. After the outbreak is contained, the industry may face some unstable fluctuations and new problems with the imbalanced recovery in the value chain and supply chain. Due to the vast resources and markets related to aquaculture in the Asia-Pacific in terms of technologies, markets, labours, and finance, the complementary aquaculture economies of the region will provide opportunities to buffer and balance such fluctuations effectively.
The Secretariat is attempting to initiate more participatory mechanisms in the network to strengthen communication and cooperation in the aquaculture sector in the Asia-Pacific. A mechanism is to extend the latitude layers of cooperation by covering the network on governance, innovation, education, training, quarantine, demonstration, business, and culture in the aquaculture sector.
Another mechanism is to establish Lead Centre-guided networks on specific subjects. Some laboratories or institutions have expressed their interests in the organization or participation of networks on some specific subjects, such as algae, aquaculture biosecurity, alien aquatic animals, aquaculture facilities, etc. A competent laboratory or institution can apply the designation of a NACA Lead Centre. Then the NACA Lead Centre can, on behalf of NACA, find other capable laboratories, institutions, colleges, and enterprises, etc. working on the subject to join a network.
NACA Member governments can also recommend participating centres. The Lead Centre is responsible for coordinating the communication and cooperation on the specific subject in the network. Then cooperation and communication can be strengthened among government, research, education, and industries for the specific subject. Cultural cooperation between media and business will also bring opportunities to advocate for the aquaculture sector.
Q.During this crisis period, farmers suffered due to price volatility. Does NACA work in ensuring remunerative prices to aquaculture farmers?
Ans: NACA has planned to organise our 13th Technical Advisory Committee Meeting (TAC13), which will mostly focus on developing a five-year strategic plan for 2020-2024 based on the regional perspective and the discussions. We hope the experts of the Members will provide a summary perspective on new, emerging, and persistent issues affecting aquaculture in the Member and the region.
However, due to the pandemic of COVID-19, we have decided to postpone the meeting to the middle of this month. Currently, the regional outbreak of COVID-19 cannot be contained on time, and international travels are still restricted. We are planning to change the physical meeting to a series of teleconference meetings. NACA Secretariat welcomes the Members to communicate their perspective on the crisis in the aquaculture sector and discuss the solutions to ensuring the recovery of the industry and remunerative price to the farmers. Besides, because of the downward trend in international trade caused by the crisis, NACA Secretariat hopes to encourage the facilitation of the regional exchange and trade of technologies, services, and products in aquaculture and to promote domestic consumption of aquatic products in the countries. We believe that many countries in the region still have great potential to improve the domestic consumption of aquatic products.
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