Infection with Marteiliodes chungmuensis

What is Marteiliodes chungmuensis?

Marteiliodes chungmuensis is a protozoan that infects molluscs. Marteiliodes chungmuensis belongs to the phylum Paramyxea.

What species of molluscs can be infected by Marteiliodes chungmuensis?

Each species of molluscs may have several common names, but only one common name is listed.

Species susceptible to Marteiliodes chungmuensis that exist in the natural environment in Canada include:

• Crassostrea gigas (Pacific cupped oyster)

Species susceptible to Marteiliodes chungmuensis that do not exist in the natural environment in Canada include:

• Crassostrea nippona (Iwagaki oyster)

Does Marteiliodes chungmuensis affect human health?

No. The causal agent of Marteiliodes chungmuensis is not a risk to human health.

What are the signs of Marteiliodes chungmuensis ?

Marteiliodes chungmuensis infects post-larval stages of molluscs.

• Disease is only observed in maturing, spawning and spent female oysters
• Maturing males can be infected but disease has not been observed

Affected molluscs may exhibit any of the following signs:

• behaviour
  • failure to spawn
  • decreased spat collection in areas where disease is found
• appearance
  • enlarged ovaries with a lumpy appearance

Is Marteiliodes chungmuensis found in Canada?

No. Marteiliodes chungmuensis has not been found in Canada.

How is Marteiliodes chungmuensis spread?

The complete life cycle of Marteiliodes chungmuensis is not known. Therefore, how infection is spread between oysters is unknown.

However, it is likely that people can spread Marteiliodes chungmuensis by moving infected molluscs and contaminated equipment.

How is Marteiliodes chungmuensis diagnosed?

Diagnosis of an infection with Marteiliodes chungmuensis requires identification of the protozoan through laboratory tests. Not all infected molluscs show signs of disease.

How is Marteiliodes chungmuensis treated?

There are no treatment options currently available to treat Marteiliodes chungmuensis.

What can I do to prevent the spread of Marteiliodes chungmuensis?

If you frequently handle or work with molluscs, be aware of the signs of Marteiliodes chungmuensis.

Do not import live infected molluscs into Canada.

• An import permit is required from the Canadian Food Inspection Agency (CFIA) for certain species of molluscs as of December 2011.
• People bringing molluscs into Canada should check other federal, provincial, and/or territorial requirements before entering the country.

Do not introduce live molluscs from another country into the natural waters of Canada.

• People releasing molluscs into the natural waters or rearing facilities within Canada should check if federal or provincial and/or territorial permits are required.

If you frequently handle or work with molluscs, be aware of where Marteiliodes chungmuensis occurs in your area.

• A federal, provincial and/or territorial permit or licence may be required to relocate molluscs within Canada.

Do not use molluscs that were bought in a grocery store as bait for catching fish or other aquatic animals.

Shells that are removed from molluscs or unwanted molluscs that you harvested or bought for your consumption should be disposed of in your municipal garbage.

The CFIA recommends that you do not visit Canadian aquaculture sites, zoos or aquariums for 14 days if you have travelled to another country and

• visited an aquaculture site, or
• had contact with wild molluscs.

Wash and disinfect the footwear you wore to the site or when you had contact with wild molluscs. Also wash your clothing thoroughly and dry it at a high temperature.

What is CFIA doing to control disease spread?

Marteiliodes chungmuensis is a reportable disease in Canada. This means that anyone who owns or works with aquatic animals, who knows of or suspects Marteiliodes chungmuensis in their molluscs, is required by law to notify the CFIA.

If Marteiliodes chungmuensis is found in Canada, the CFIA would control its spread by implementing disease response activities. These may include

• controlling the movements of infected animals that people own or work with
• humanely destroying infected animals
• cleaning and disinfecting

The control measures chosen would depend on the situation.

What do I do if I think molluscs that I am raising or keeping have Marteiliodes chungmuensis?

If you suspect that molluscs you are raising or keeping have Marteiliodes chungmuensis, you are required under the Health of Animals Act to immediately notify the CFIA of your suspicion.

How do I get more information

For more information about reportable diseases, visit the Aquatic Animal Health page, contact your local CFIA Animal Health Office, or your CFIA Area office:

• Atlantic: 506-777-3939
• Quebec: 514-283-8888
• Ontario: 226-217-8555
• West: 587-230-2200