Question: Which species from the deer family move solitarily and are susceptible to the Parelaphostrongylus tenuis parasite?
Context: The elk, or wapiti ("Cervus canadensis"), is one of the largest species within the deer family, Cervidae, in the world, and one of the largest land mammals in North America and Eastern Asia.  This animal should not be confused with the still larger moose ("Alces alces") to which the name "elk" applies in British English and in reference to populations in Eurasia.  Apart from the moose, the only other member of the deer family to rival the elk in size is the south Asian sambar ("Rusa unicolor"). The name deer botfly (also deer nose bot) refers to any species in the genus Cephenemyia (sometimes misspelled as "Cephenomyia" or "Cephenemya"), within the family Oestridae.  They are large, gray-brown flies, often very accurate mimics of bumblebees.  They attack chiefly the nostrils and pharyngeal cavity of members of the deer family.  The larva of "Cephenemyia auribarbis", infesting the stag, is called a stagworm.  The genus name comes from the Greek "kēphēn", drone bee, and "myia", fly. 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.  Several known species fall under the "Mammomonogamus" genus, 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.  Cases have been reported from the Caribbean, China, Korea, Thailand, and Philippines.  The worm usually inhabits the upper-respiratory region in the trachea, bronchus, or larynx, and can elicit chronic coughing and asthma-like symptoms.  One interesting case from Thailand reported finding worms in the patient's duodenum, suggesting "M. laryngeus" can also be a gastrointestinal parasite.  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. Sphaerothecum destruens (the rosette agent) is a parasite of fish.  It was first discovered in the United States in association with invasive species including topmouth gudgeon but was found to be the causative agent of a disease in the UK affecting salmonid species such as Atlantic salmon and brown trout.  It is thought to pose more of a risk in Europe than in the USA as native species there are more susceptible to the parasite.  The disease causes high rates of morbidity and mortality in a number of different salmonid species and can also infect other UK freshwater fish such as bream, carp and roach.  The genus "Sphaerothecum" is closely related to the genera "Dermocystidium" and "Rhinosporidium". The moose (North America) or elk (Eurasia), "Alces alces", is the largest extant species in the deer family.  Moose are distinguished by the broad, flat (or "palmate") antlers of the males; other members of the family have antlers with a dendritic ("twig-like") configuration.  Moose typically inhabit boreal forests and temperate broadleaf and mixed forests of the Northern Hemisphere in temperate to subarctic climates. Hunting and other human activities have caused a reduction in the size of the moose's range over time.  Moose have been reintroduced to some of their former habitats.  Currently, most moose are found in Canada, Alaska, New England, Fennoscandia, Baltic States, and Russia.  Their diet consists of both terrestrial and aquatic vegetation.  The most common moose predators are the gray wolf along with bears and humans. Unlike most other deer species, moose are solitary animals and do not form herds.  Although generally slow-moving and sedentary, moose can become aggressive and move quickly if angered or startled.  Their mating season in the autumn features energetic fights between males competing for a female. Moose sickness is a degenerative condition that occurs in moose populations in central and eastern North America that have been infected with the parasitic worm Parelaphostrongylus tenuis.  The disease is characterized by stumbling, aimlessness and other odd behavior and is often fatal. Procambarus tenuis is a species of crayfish in the genus "Procambarus" in the family Cambaridae.  It is the only species in the subgenus Procambarus (Tenuicambarus).  "P. tenuis" is rare throughout its range, which is restricted to the Ouachita Mountains of Le Flore County, Oklahoma and Polk County, Arkansas. Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of mule deer, white-tailed deer, elk (or "wapiti"), moose, and reindeer.  As of 2016, CWD had only been found in members of the deer family.  First recognized as a clinical "wasting" syndrome in 1967 in mule deer in a wildlife research facility in northern Colorado, USA, it was identified as a TSE in 1978 and has spread to free-ranging and captive populations in 23 US states and two Canadian provinces.  CWD is typified by chronic weight loss leading to death.  No relationship is known between CWD and any other TSE of animals or people. Parelaphostrongylus tenuis (also known as meningeal worm, brainworm, or moose illness) is a neurotropic nematode parasite common to white-tailed deer, "Odocoileus virginianus", which causes damage to the central nervous system.  Moose ("Alces alces"), elk ("Cervus canadensis"), caribou ("Rangifer tarandus"), and mule deer ("Odocoileus hemionus") are also susceptible to the parasite but are aberrant hosts and are infected in neurological instead of meningeal tissue.  The frequency of infection in these species increases dramatically when their ranges overlap high densities of white-tailed deer. Musk deer can refer to any one, or all seven, of the species that make up Moschus, the only extant genus of the family Moschidae.  The musk deer family differs from cervids, or true deer, by lacking antlers and facial glands and by possessing only a single pair of teats, a gallbladder, a caudal gland, a pair of tusk-like teeth and—of particular economic importance to humans—a musk gland.
Answer: moose