The outbreak of the COVID-19 pandemic has found the Democratic Republic of Congo (DRC) in the middle of attempting to avert the spread of a separate outbreak – epizootic ulcerative syndrome (EUS) – caused by an infection of A. invadans among wild fish caught on the streams and rivers in the country’s Equateur province.
By the time the first COVID-19 case was confirmed in DRC on 10 March, the country – which is also battling an increase in Ebola cases and resurgence in insecurity perpetrated by militia groups in some provinces – was nearly five years behind schedule in the implementation of the recommendations by a Food and Agriculture Organization (FAO) EUS investigation task force, largely because of prolonged heightened political activity leading to the 2018 national elections.
The FAO investigating team – International Emergency Fish Disease Investigation Mission on a Suspected Outbreak of EUS – was launched in early 2015 to probe causes of diseased and poor-quality fish in the Libala, Loko, and Mongala rivers, in DRC’s Equateur province, where seafood is a key food security item.
Between 13 and 19 March, 2015, the FAO team visited the affected fishing areas, conducted field investigations and laboratory tests, and confirmed widespread presence of EUS – which may have been triggered by the presence of low water pH that “favors infectivity with A. invadans.”
“The seasonal flooding cycles causing migration of fish into swampy areas will promote seasonal outbreaks of the disease,” the team said.
Fish from three of the 12 families investigated by the FAO team were found to be the most affected by the disease. These fish species families include Clariidae, Channidae and Protopterdae, which are susceptible not only to catching the disease but also spreading it because they are “air-breathing and marketable fish that is transported to and from markets alive.”
DRC’s inland water capture production is estimated at 230,000 metric tons (MT) and has been increasing on average of 2 percent annually since 2005, according to the FAO’s 2018 State of World Fisheries and Aquaculture report. Although between 2005 and 2014 the production grew to 224,263 MT, the output was maintained at 227,700 MT and 229,300 MT for 2015 and 2016, respectively, according to the report.
For this inland water output to be sustained or even increased, the FAO team recommends several measures to contain EUS, such as streamlining fish diseae notification structures to ensure quick relaying of information by veterinary officers whenever there is an outbreak to the World Organization for Animal Health (OIE) and also stepping up of fish markets’ surveillance to enable the immediate tracing of the origin of the diseased fish.
“The movement of live fish between markets and between river systems in areas affected by EUS needs to be restricted as well as a ban of fishing activities during the EUS-outbreak seasons,” the FAO team recommended.
Furthermore, the team urged the DRC government to launch mass public sensitization forums on EUS after training key fisheries sector personnel.
The FAO investigating team also called for funding to carry out detailed study on EUS trends in DRC, mapping out of affected areas, and revamping the laboratory facilities in the country – particularly the one in the capital, Kinshasa.
“The current challenge is to formulate concrete and effective responses by the government of DRC with the support of FAO, OIE, and other relevant organizations and stakeholders to curtail the spread of the disease,” the report said.
Meanwhile, the report warns of a possible spread of EUS from one lake or river to another, “endangering susceptible fish species as well as neighbouring countries.”
The report identifies factors that could contribute to the spread of EUS to include heavy rainfall and flooding, poor biosecurity, including movement of infected fish, as well as natural spread by fish and birds.
With the report concluding that “there is no known prospective vaccine nor effective chemotherapeutant for EUS and treatment of EUS in natural water bodies is not possible,” DRC is expected to step up measures that would result in identifying and reducing channels of EUS spread.
For now, DRC is relying on imports from China, Egypt, Namibia, Kenya, Tanzania, Rwanda, and Uganda to feed those reliant on the affected local fish populations as a key part of their diets.
Photo courtesy of Dr. David Huchzemeyer/FAO
