''Neorickettsia helminthoeca'' is a bacterium in the ''

Neorickettsia ''Neorickettsia'' is a genus of bacteria. Species or strains in this genus are coccoid or pleomorphic cells that reside in cytoplasmic vacuoles within monocytes and macrophages of dogs, horses, bats, and humans. '' Neorickettsia sennetsu'' ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

that causes

Salmon poisoning disease ''Neorickettsia helminthoeca'' is a bacterium in the ''Neorickettsia'' genus that causes Salmon poisoning disease. Salmon poisoning disease Salmon poisoning disease (SPD) is a fatal disease of dogs and other canids caused by a rickettsial bacte ...

Salmon poisoning disease

Salmon poisoning disease (SPD) is a fatal disease of

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

s and other

canid Canidae (; from Latin, ''canis'', "dog") is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid (). There are three subfamilies found within the ...

s caused by a

rickettsial ''Rickettsia'' is a genus of nonmotile, gram-negative, nonspore-forming, highly pleomorphic bacteria that may occur in the forms of cocci (0.1 μm in diameter), bacilli (1–4 μm long), or threads (up to about 10 μm long). The term "rickett ...

bacterium, ''Neorickettsia helminthoeca''. It results from eating raw

salmon Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...

trout Trout are species of freshwater fish belonging to the genera '' Oncorhynchus'', ''Salmo'' and ''Salvelinus'', all of the subfamily Salmoninae of the family Salmonidae. The word ''trout'' is also used as part of the name of some non-salmoni ...

, or

salamander Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All ten ...

and is common in the

Pacific Northwest The Pacific Northwest (sometimes Cascadia, or simply abbreviated as PNW) is a geographic region in western North America bounded by its coastal waters of the Pacific Ocean to the west and, loosely, by the Rocky Mountains to the east. Though ...

. These fish and amphibians are infected with the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e of a

fluke Fluke may refer to: Biology * Fluke (fish), a species of marine flatfish * Fluke (tail), the lobes of the tail of a cetacean, such as dolphins or whales, ichthyosaurs, mosasaurs Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Greek ...

, ''

Nanophyetus salmincola ''Nanophyetus salmincola'' is a food-borne intestinal trematode parasite prevalent on the Pacific Northwest coast. The species may be the most common trematode endemic to the United States. The life cycle of the ''N. salmincola'' requires thr ...

'' through an

intermediate host In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include a ...

, the

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

'' Oxytrema plicifer''. The larvae attaches to the intestine of the dog and the

bacteria are released, causing severe gastrointestinal disease and systemic infection. '' Neorickettsia elokominica'', carried by the same fluke, causes a similar disease known as Elokomin fluke fever (EFF) in canids,

bear Bears are carnivoran mammals of the family Ursidae. They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Nor ...

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...

s, and

ferret The ferret (''Mustela furo'') is a small, Domestication, domesticated species belonging to the family Mustelidae. The ferret is most likely a domesticated form of the wild European polecat (''Mustela putorius''), evidenced by their Hybrid (biol ...

Symptoms

Symptoms of SPD begin about one week after eating the salmon and include vomiting, diarrhea, loss of appetite, depression, high fever, and enlarged

lymph node A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that inclu ...

s. Untreated,

mortality Mortality is the state of being mortal, or susceptible to death; the opposite of immortality. Mortality may also refer to: * Fish mortality, a parameter used in fisheries population dynamics to account for the loss of fish in a fish stock throug ...

reaches 90 percent. Death occurs seven to ten days after symptoms begin. EFF has less severe symptoms than SPD, with less gastrointestinal signs and more lymph node involvement. The mortality in untreated cases is about 10 percent. A similar disease has been identified in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Diagnosis

Diagnosis is through finding the fluke eggs microscopically in a stool sample. A

needle aspiration biopsy Fine-needle aspiration (FNA) is a diagnostic procedure used to investigate lumps or masses. In this technique, a thin (23–25 gauge (0.52 to 0.64 mm outer diameter)), hollow needle is inserted into the mass for sampling of cells that, aft ...

of an enlarged lymph node will reveal rickettsial organisms within

macrophage Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer cel ...

s in many cases. The rickettsial infection can be successfully treated with

tetracycline Tetracycline, sold under various brand names, is an oral antibiotic in the tetracyclines family of medications, used to treat a number of infections, including Acne vulgaris, acne, cholera, brucellosis, plague (disease), plague, malaria, and sy ...

, and the fluke infection can be treated with

fenbendazole Fenbendazole is a broad spectrum benzimidazole anthelmintic used against gastrointestinal parasites including: giardia, roundworms, hookworms, whipworms, the tapeworm genus '' Taenia'' (but not effective against ''Dipylidium caninum'', a common d ...

References

{{Taxonbar, from=Q50231157 Rickettsiales Bacteria described in 1953 Dog diseases