Mammomonogamus
Mammomonogamus is a genus of parasitic nematodes of the family Syngamidae that parasitise the respiratory tracts of cattle, sheep, goats, deer, cats, orangutans, and elephants. The nematodes can also infect humans and cause the disease called mammomonogamiasis.[1] Several known species fall under the genus Mammomonogamus, but the most common species found to infest humans is M. laryngeus. Infection in humans is very rare, with only about 100 reported cases worldwide, and is assumed to be largely accidental.[2] Cases have been reported from the Caribbean,[3] China,[4] Korea,[5] Thailand,[6] and Philippines.[7]
The worm usually inhabits the upper-respiratory region in the trachea, bronchus, or larynx, and can elicit chronic coughing and asthma-like symptoms.[8] One interesting case from Thailand reported finding worms in the patient's duodenum, suggesting M. laryngeus can also be a gastrointestinal parasite.[6] More research is needed because the life cycle is not completely known. Diagnosis is made by recovering the worms on bronchoscopy or oesophagogastroduodenoscopy. Due to the scant amount of information available on this parasite in literature, increased awareness is necessary, especially in endemic areas near M. laryngeus’ reservoir hosts, for clinicians, the local population in the endemic area, and traveling tourists, to effectively recognize and prevent mammomonogamiasis.[citation needed]
Mammomonogamus is classified in the family Syngamidae. The Syngamidae are in the superfamily Strongyloidae and order Strongylata, making them close relatives to hookworms and other nematodes.[6]
The generic name Mammomonogamus is derived from the Latin term mamma ('breast'), and the Greek terms monos (μόνος 'single') and gamos (γάμος 'marriage'),[9] which most likely is referring to the distinct characteristic of the male and female worm acting as a single unit through the male being joined in permanent copulation to the middle portion of the female's body.
Species within this genus are M. laryngeus, M. nasicola, M. gangguiensis,[2] and M. auris.[10] Only M. laryngeus is known to infect and cause disease in humans.[6] Because of the close resemblance of M. laryngeus to the gapeworm from the genus Syngamus that commonly infect birds, M. laryngeus was originally called Syngamus laryngeus and Syngamus kingi.[6] The classification was revised in 1948 when Ryzhikov reconstructed the phylogenetic relationship of the family Syngamidae and recategorized the parasite as M. laryngeus.[11]
Infestation with M. laryngeus has been called mammomonogamiasis, mammomonogamosis, syngamosis', or 'syngamiasis.[12]
