Marine Hepatopancreatic Microsporidiosis (HPM) is an emerging infectious disease of marine fish and invertebrates. It’s caused by the protozoan parasite, Microsporidium hepatopancreaticum, which typically infects the pancreas or biliary tract of its host. HPM is characterized by a range of clinical signs, including abdominal swelling, anorexia, jaundice, ascites, and death. HPM is difficult to diagnose clinically due to its non-specific clinical signs. Diagnosing HPM requires the detection of the causative agent using molecular techniques such as PCR or immunofluorescence. Treatment for HPM is currently limited to supportive care with antibiotics and antifungals.
The mode of transmission of the HPM pathogen is not fully understood, though it has been suggested that environmental contamination could play a role. Environmental sources of infection include water, sediment, food and other animals, particularly crustaceans. Contaminated feed and live fish can also potentially act as sources of infection for susceptible species. Transmission between hosts has been suggested to occur through coprophagy, fecal-oral contact and water contact.
HPM is an emerging disease in many countries, including the United States, Canada, Japan and Korea. In areas with a high prevalence of HPM, it’s important to implement measures for disease control and prevention. These measures include the use of clean and uncontaminated feed, proper disposal of fish waste and regular disinfection of tanks and equipment. It’s important to implement biosecurity measures such as quarantining new fish.
Symptoms of Marine Hepatopancreatic Microsporidiosis (HPM)
- Abdominal swelling
- Anorexia
- Jaundice
- Ascites
- Death in severe cases
Diagnosing Marine Hepatopancreatic Microsporidiosis (HPM)
Marine hepatopancreatic microsporidiosis (HPM) is difficult to diagnose clinically due to its non-specific clinical signs. Diagnosing of HPM requires the detection of the causative agent using molecular techniques such as PCR or immunofluorescence.
Stages of Marine Hepatopancreatic Microsporidiosis (HPM)
Early stage:
In the early stages of HPM, the parasite is mainly localized in the pancreas and biliary tract of the host, causing abdominal swelling and anorexia.
Advanced stage:
In more advanced stages of HPM, the parasite has spread through the body and can cause jaundice, ascites and death in severe cases.
Treating Marine Hepatopancreatic Microsporidiosis (HPM)
Treatment for HPM is currently limited to supportive care with antibiotics and antifungals. It’s important to implement biosecurity measures such as quarantining new stock and preventing the movement of fish from one facility to another. Controlling environmental sources of infection by using clean feed, proper disposal of fish waste and regular disinfection of tanks and equipment can help prevent the spread of HPM.
Preventing Marine Hepatopancreatic Microsporidiosis (HPM)
In areas with a high prevalence of HPM, it’s important to implement measures for disease control and prevention. These measures include the use of clean and uncontaminated feed, proper fish waste disposal and regular tank disinfection and equipment. It’s important to implement biosecurity measures such as quarantining new stock and preventing the movement of fish from one facility to another.