Recovery is most likely if it is spotted within the first 24–48 hours, and you should seek veterinary advice—a vet may choose to give the animal drugs.

The sick animal should be kept in a cage by itself so that others do not catch the disease—wet tail can be very contagious so sanitize all objects the animal has come in contact with (wheel, food dish, huts, etc.).

If the animal doesn't want to eat, then dry, unflavored oats can be hand fed, which can also help with the diarrhea. The animal should only be fed dry foods, any foods with a high water content should be avoided.

If the animal has an unclean or matted rear-end, this should not be remedied using a bath in water—instead a q-tip (cotton bud) or cotton ball can be used to very gently clean the animal's rear end to avoid discomfort or rashes.

If the animal is not drinking, hydration can be aided by scruffing (i.e. very gently holding the rodent by the extra skin on the back of the neck) the animal so that they open their mouth; then in small, short intervals, water can be provided with a 1 ml syringe. It is very important that this is done slowly, to avoid getting water down the animal's wind pipe. Unflavored pedialyte can be purchased from a grocery store and can be very helpful with wet tail. If feeding is also an issue, a suggested aide is to feed extremely small amounts of no garlic, no onion, no added sugar mashed baby food, and administered using the same scruffing method, and again at a very slow pace.

Wet-tail is a disease in the animal's intestines caused by the bacteria, "Lawsonia intracellularis". Wet-tail is a stress related illness—such stress can be caused by a variety of factors, including:

- Too much handling

- Change in environment

- Change in diet

- Extremely unclean caging

- Being away from mother and/or siblings

- Illness or death of a pair-bond or mate

Currently, the most effective treatment is transferring the affected fish to a freshwater bath for a period of 2 to 3 hours. This is achieved by towing the sea cages into fresh water, or pumping the fish from the sea cage to a tarp filled with fresh water. Mortality rates have been lowered by adding Levamisole to the water until the saturation is above 10ppm. Due to the difficulty and expense of treatment, the productivity of salmon aquaculture is limited by access to a source of fresh water. Chloramine and chlorine dioxide have also been used. Other potential in-feed treatments such as immunosupportive-based feeds, mucolytic compounds such as L-cysteine ethyl ester and the parasticide bithionol have been tested with some success although not developed for commercial use.

To date, no treatment for IBD is known. Snakes diagnosed with or suspected of having IBD should be euthanized because progression and transmission of the virus is both very rapid and destructive. All newly acquired snakes should, therefore, be quarantined for at least 3 and preferably 6 months before being introduced into established collections. The recommended period of quarantine for any wild-caught boa or python is at least 4–6 months.

The primary route of transmission has not yet been identified, but direct contact may result in its transmission to developing embryos in viviparous species and eggs in oviparous species. Venereal transmission is also indicated as a possibility. The snake mite, "Ophionyssus natricis", has been implicated as a possible vector for the virus, since mite infestations are commonly seen in epizootics of IBD and in captive specimens of these snakes. Mites are sometimes very difficult to eradicate due to their resistance to certain toxins used to eliminate them.

Permethrin is known to be effective against mite infestations, but should be used with great caution and only in small quantities due to their toxic nature. Also, several nonchemical substances may be just as effective. These biological agents are sprayed onto the infested animal and desiccate the mites, rendering them unable to lay their eggs or consume blood beneath the scales of their host. The incubation period for mite eggs is thought to be about 10–14 days, so the treatment should be repeated after 10 days to ensure that any eggs that hatch or larvae that develop into nymphs are also quickly eliminated from the host before reaching sexual maturity and able to repeat their reproduction cycle.

Digital dermatitis is a polymicrobial disease involving treponemes and other anaerobes. Treponemes are the bacterium most commonly found in lesions. Their abundance increases as the lesion progresses. They account for 94% of bacterial sequences detected in chronic lesions.

Symptoms typically begin to appear two months after the fish are transferred from freshwater hatcheries to open net sea cages. Symptoms include mucus build-up on the gills of infected fish and hyper-plastic lesions, causing white spots and eventual deterioration of the gill tissue. Fish will show signs of dyspnoea such as rapid opercular movements and lethargy. Although usually recognised by hyperplastic and proliferative gill lesions, the effects of AGD occur before oxygen transfer across the gill is severely compromised. AGD affected fish show a significant increase in vascular resistance contributing to cardiovascular collapse. Such effects result in compensatory changes in heart shape to improve its efficiency at pumping blood.

Contributing factors are an ambient water temperature above 16 degrees Celsius, crowding and poor water circulation inside the sea pens. Clinical cases are more common in the Summer. The lesions on the gills are highly suggestive of infection. Gill biopsies can be observed under the microscope for amoebas, or tested using fluorescent antibody testing.

Treatment of lesions of digital dermatitis is done by topical application of agents to the affected skin. The skin should be cleaned and kept dry prior treatment. Topical oxytetracycline (OTC) is often referred as the most reliable treatment as cows treated with OTC have a good recovery rate. Bandaging the lesion is often undertaken but there is no evidence of any benefit and bandaging can provide the anaerobic environment which supports the spirochaetes.. Systemic antibiotics are not needed.

Control and prevention of digital dermatitis relies on prompt detection, isolation and treatment of affected cattle. Group hoof disinfection can be achieved via the passage of the cows through footbaths of antimicrobial solutions. Slurry build-up should be avoided since organic matter can impair the antimicrobial efficacy of the footbath solutions. Regular footbaths should be organised, using formalin, copper sulphate or a thymol-based disinfectant. While regular footbathing can help prevent hoof infections, occasional flare-up of active M2 lesions can happen.

Screening tools for contact granulomas are not currently available. Diagnosis of contact granulomas require visualization using laryngoscopy, and may require further biopsy for differential diagnosis. A combination of symptoms and lifestyle factors may be linked with the development of a contact granuloma, however symptoms vary greatly by individual. Some lifestyle factors that have been linked with elevated risk of development of contact granulomas include frequent use of the voice, especially when in loud environments, and concurrent use of the voice with alcohol consumption (increasing risk of gastroesophageal reflux symptoms). Contact granuloma may also arise after intubation, and so following intubation, patients should be monitored if voice symptoms arise. Symptoms may or may not include hoarse voice, described as "huskiness" by some patients, "aching" in the throat related to increased effort to produce voice, and the feeling of having a lump in one's throat when swallowing. It is also possible to have no such symptoms, especially if the granuloma is small. A patient presenting with such symptoms or risk factors should therefore be referred for further visualization. It is therefore recommended to obtain a diagnosis from a doctor.

Diagnosis may be simple in cases where the patient's signs and symptoms are idiopathic to a specific cause. However this is generally not the case, considering that many pathogens which cause enteritis may exhibit the similar symptoms, especially early in the disease. In particular, "campylobacter, shigella, salmonella" and many other bacteria induce acute self-limited colitis, an inflammation of the lining of the colon which appears similar under the microscope.

A medical history, physical examination and tests such as blood counts, stool cultures, CT scans, MRIs, PCRs, colonoscopies and upper endoscopies may be used in order to perform a differential diagnosis. A biopsy may be required to obtain a sample for histopathology.

Various methods are used to diagnose contact granuloma which aid in differentiating it from other vocal fold pathology. Laryngoscopy can allow visualization of the suspected granuloma while also checking for signs of vocal abuse. Laryngoscopy, as well as an acoustic analysis of the voice, can help rule out vocal fold paresis as an underlying cause. Microscopic examination of the tissue can help determine that the lesion is benign rather than cancerous, as would be the case in contact granuloma. Other methods such as laryngeal electromyography and reflux testing can also be used to evaluate the function of the vocal folds and determine if laryngopharyngeal reflux is contributing to the pathology.

The CDC states that PCR testing from a single blood draw is not sufficiently sensitive for "B." "henselae" testing, and can result in high false negative rates due to a small sample volume and levels below the limit of molecular detection.

"Bartonella" spp. are fastidious, slow-growing bacteria that are difficult to grow using traditional solid agar plate culture methods due to complex nutritional requirements and potentially a low number of circulating bacteria. This conventional method of culturing "Bartonella" spp. from blood inoculates plated directly onto solid agar plates requires an extended incubation period of 21 days due to the slow growth rate.

"Bartonella" growth rates improve when cultured in an enrichment inoculation step in a liquid insect-based medium such as "Bartonella" α-Proteobacteria Growth Medium (BAPGM) or Schneider’s Drosophila-based insect powder medium. Several studies have optimized the growing conditions of "Bartonella" spp. cultures in these liquid media, with no change in bacterial protein expressions or host interactions "in vitro". Insect-based liquid media supports the growth and co-culturing of at least seven "Bartonella" species, reduces bacterial culturing time and facilitates PCR detection and isolation of "Bartonella" spp. from animal and patient samples. Research shows that DNA may be detected following direct extraction from blood samples and become negative following enrichment culture, thus PCR is recommended after direct sample extraction and also following incubation in enrichment culture. Several studies have successfully optimized sensitivity and specificity by using PCR amplification (pre-enrichment PCR) and enrichment culturing of blood draw samples, followed by PCR (post-enrichment PCR) and DNA sequence identification.

Many canine skin disorders can have a basis in poor nutrition. The supplementation of both omega fatty acids, 3 and 6, have been shown to mediate the inflammatory skin response seen in chronic diseases. Omega 3 fatty acids are increasingly being used to treat pruritic, irritated skin. A group of dogs supplemented with omega 3 fatty acids (660 mg/kg [300 mg/lb] of body weight/d) not only improved the condition of their pruritus, but showed an overall improvement in skin condition. Furthermore, diets lacking in essential fatty acids usually present as matted and unkept as the first sign of a deficiency. Eicosapentaenoic acid (EPA), a well known omega 3, works by preventing the synthesis of another omega metabolite known as arachidonic acid. Arachidonic acid is an omega 6, making it pro-inflammatory. Though not always the case, omega 6 fatty acids promote inflammation of the skin which in turn reduces overall appearance and health. There are skin benefits of both these lipids, as a deficiency in omega 6s leads to a reduced ability to heal and a higher risk of infection, which also diminishes skin health. Lipids in general benefit skin health of dogs, as they nourish the epidermis and retain moisture to prevent dry, flaky skin.

Mild cases usually do not require treatment and will go away after a few days in healthy people. In cases where symptoms persist or when it is more severe, specific treatments based on the initial cause may be required.

In cases where diarrhoea is present, replenishing fluids lost is recommended, and in cases with prolonged or severe diarrhoea which persists, intravenous rehydration therapy or antibiotics may be required. A simple oral rehydration therapy (ORS) can be made by dissolving one teaspoon of salt, eight teaspoons of sugar and the juice of an orange into one litre of clean water. Studies have shown the efficacy of antibiotics in reducing the duration of the symptoms of infectious enteritis of bacterial origin, however antibiotic treatments are usually not required due to the self-limiting duration of infectious enteritis.

It is important to differentiate DPI from small intestinal obstruction, since obstruction may require surgical intervention, but this can at times be difficult. Horses suffering from DPI usually have a higher protein concentration in their peritoneal fluid compared to horses with small intestinal obstruction, often without a concurrent increase in nucleated cell count. They usually have some relief and decrease in pain after gastric decompression, while horses with an obstruction often still act colicky after nasogastric intubation. Distention of the small intestine may be less than what is felt on rectal examination of horses with obstruction, especially after gastric decompression. Horses with DPJ usually produce larger volumes of reflux (usually greater than 48 liters in the first 24 hours) than those with obstruction, and are often pyretic (temperatures of 101.5–102.5) and have alterations in white blood cell levels, while those with obstructions usually have a normal or lower than normal temperature and normal leukocyte levels.

Ultrasound can also be helpful to distinguish DPJ from obstruction. Horses with small intestinal obstruction will usually have an intestinal diameter of −10 cm with a wall thickness of 3–5mm. Horses with proximal enteritis usually have an intestinal diameter that is narrower, but wall thickness is often greater than 6mm, containing a hyperechoic or anechoic fluid, with normal, increased, or decreased peristalsis. However, obstructions that have been present for some time may present with thickened walls and distention of the intestine.

DPJ can only be definitively diagnosed during surgery or at necropsy, when its gross appearance of the small intestine may be evaluated.

Some systemic diseases can become symptomatic as a skin disorder. These include many endocrine (hormonal) abnormalities, such as hypothyroidism, Cushing's Syndrome (hyperadrenalcorticism), and tumors of the ovaries or testicles.

Horses may develop pharyngitis, laryngitis, or esophagitis secondary to indwelling nasogastric tube. Other complications include thrombophlebitis, laminitis (which subsequently reduces survival rate), and weight loss. Horses are also at increased risk of hepatic injury.

Survival rates for DPJ are 25–94%. Horses that survive the incident rarely have reoccurrence.

The diagnosis is usually made based upon the clinical appearance, and swabs can be taken of the surface of the denture. Investigations to rule out possibility of diabetes may be indicated. Tissue biopsy is not usually indicated, but if taken shows histologic evidence of proliferative or degenerative responses and reduced keratinization and epithelial atrophy.

Diagnosis is confirmed histologically by tissue biopsy. Hematoxylin-eosin stain of biopsy slide will show features of Langerhans Cell e.g. distinct cell margin, pink granular cytoplasm. Presence of Birbeck granules on electron microscopy and immuno-cytochemical features e. g. CD1 positivity are more specific. Initially routine blood tests e.g. full blood count, liver function test, U&Es, bone profile are done to determine disease extent and rule out other causes. Radiology will show osteolytic bone lesions and damage to the lung. The latter may be evident in chest X-rays with micronodular and interstitial infiltrate in the mid and lower zone of lung, with sparing of the Costophrenic angle or honeycomb appearance in older lesions. MRI and CT may show infiltration in sella turcica. Assessment of endocrine function and bonemarrow biopsy are also performed when indicated.

- S-100 protein is expressed in a cytoplasmic pattern

- peanut agglutinin (PNA) is expressed on the cell surface and perinuclearly

- major histocompatibility (MHC) class II is expressed (because histiocytes are macrophages)

- CD1a

- langerin (CD207), a Langerhans Cell–restricted protein that induces the formation of Birbeck granules and is constitutively associated with them, is a highly specific marker.

Yersiniosis is usually self-limiting and does not require treatment. For severe infections (sepsis, focal infection) especially if associated with immunosuppression, the recommended regimen includes doxycycline in combination with an aminoglycoside. Other antibiotics active against "Y. enterocolitica" include trimethoprim-sulfamethoxasole, fluoroquinolones, ceftriaxone, and chloramphenicol. "Y. enterocolitica" is usually resistant to penicillin G, ampicillin, and cephalotin due to beta-lactamase production.

Treatment for gastroenteritis due to "Y. enterocolitica" is not needed in the majority of cases. Severe infections with systemic involvement (sepsis or bacteremia) often requires aggressive antibiotic therapy; the drugs of choice are doxycycline and an aminoglycoside. Alternatives include cefotaxime, fluoroquinolones, and co-trimoxazole.

Rare diseases are usually genetic and are therefore chronic. EURORDIS estimates that at least 80% of them have identified genetic origins. Other rare diseases are the result of infections and allergies or due to degenerative and proliferative causes.

Symptoms of some rare diseases may appear at birth or in childhood, whereas others only appear once adulthood is reached.

Research publications emphasize rare diseases that are chronic or incurable, although many short-term medical conditions are also rare diseases.

Denture-related stomatitis is usually a harmless condition with no long term consequences. It usually resolves with simple measures such as improved denture hygiene or topical antifungal medication. In severely immunocompromised individuals (e.g. those with HIV), the infection may present a more serious threat.

Tissue biopsy is usually indicated to rule out other causes of white patches and also to enable a detailed histologic examination to grade the presence of any epithelial dysplasia. This is an indicator of malignant potential and usually determines the management and recall interval. The sites of a leukoplakia lesion that are preferentially biopsied are the areas that show induration (hardening) and erythroplasia (redness), and erosive or ulcerated areas. These areas are more likely to show any dysplasia than homogenous white areas.

Brush biopsy/exfoliative cytology is an alternative to incisional biopsy, where a stiff brush is scraped against the lining of the mouth to remove a sample of cells. This is then made into a smear which can be examined microscopically. Sometimes the biopsy site can be selected with adjunct methods which aim to highlight areas of dysplasia. Toluidine blue staining, where the dye is preferentially retained by dysplastic tissue, is sometimes used, but there is high false positive rate. Other methods involve the use of illuminescence, relying on either the property of normal autoflorescent molecules in mucosa such as collagen and keratin which is lost from areas of dysplasia or carcinoma under blue light, or by initially staining of the mucosa with toluidine blue or dilute acetic acid and examination under white light.