It is done through isolation of a bacteria from chickens suspected to have history of coryza and clinical finds from infected chickens also is used in the disease diagnosis. Polymerase chain reaction is a reliable means of diagnosis of the disease

Diagnosis of lymphoid tumors in poultry is complicated due to multiple etiological agents capable of causing very similar tumors. It is not uncommon that more than one avian tumor virus can be present in a chicken, thus one must consider both the diagnosis of the disease/tumors (pathological diagnosis) and of the virus (etiological diagnosis). A step-wise process has been proposed for diagnosis of Marek’s disease which includes (1) history, epidemiology, clinical observations and gross necropsy, (2) characteristics of the tumor cell, and (3) virological characteristics

The demonstration of peripheral nerve enlargement along with suggestive clinical signs in a bird that is around three to four months old (with or without visceral tumors) is highly suggestive of Marek's disease. Histological examination of nerves reveals infiltration of pleomorphic neoplastic and inflammatory lymphocytes. Peripheral neuropathy should also be considered as a principal rule-out in young chickens with paralysis and nerve enlargement without visceral tumors, especially in nerves with interneuritic edema and infiltration of plasma cells.

The presence of nodules on the internal organs may also suggest Marek's disease, but further testing is required for confirmation. This is done through histological demonstration of lymphomatous infiltration into the affected tissue. A range of leukocytes can be involved, including lymphocytic cell lines such as large lymphocyte, lymphoblast, primitive reticular cells, and occasional plasma cells, as well as macrophage and plasma cells. The T cells are involved in the malignancy, showing neoplastic changes with evidence of mitosis. The lymphomatous infiltrates need to be differentiated from other conditions that affect poultry including lymphoid leukosis and reticuloendotheliosis, as well as an inflammatory event associated with hyperplastic changes of the affected tissue.

Key clinical signs as well as gross and microscopic features that are most useful for differentiating Marek’s disease from lymphoid leukosis and reticuloendotheliosis include (1) Age: MD can affect birds at any age, including 5% in unvaccinated flocks; (4) Potential nerve enlargement; (5) Interfollicular tumors in the bursa of Fabricius; (6) CNS involvement; (7) Lymphoid proliferation in skin and feather follicles; (8) Pleomorphic lymphoid cells in nerves and tumors; and (9) T-cell lymphomas.

In addition to gross pathology and histology, other advanced procedures used for a definitive diagnosis of Marek’s disease include immunohistochemistry to identify cell type and virus-specific antigens, standard and quantitative PCR for identification of the virus, virus isolation to confirm infections, and serology to confirm/exclude infections.

The World Organisation for Animal Health (OIE) reference laboratories for Marek’s disease include the Pirbright Institute, UK and the USDA Avian Disease and Oncology Laboratory, USA.

Because the risk of meningococcal disease is increased among USA's military recruits, all military recruits routinely receive primary immunization against the disease.

Prevention is through use of Stock coryza-free birds. In other areas culling of the whole flock is a good means of the disease control. Bacterin also is used at a dose of two to reduce brutality of the disease. Precise exposure has also has been used but it should be done with care. Vaccination of the chicks is done in areas with high disease occurrence. Treatment is done by using antibiotics such as erythromycin, Dihydrostreptomycin, Streptomycin sulphonamides, tylosin and Flouroquinolones .

College students who plan to live in dormitories receive primary immunization with meningitis A, C, Y and W-135 vaccines, although the risk for meningococcal disease for college students 18–24 years of age is similar to that of the general population of similar age. College students consider vaccination against meningococcal disease to reduce their risk for the disease and state that college healthcare providers should take a proactive role in providing information about meningococcal disease to students and their parents.

Routine primary immunization against meningococcal disease is recommended for most adults living in endemic areas or planning to travel to such areas. Although conjugate vaccines are the preferred meningococcal vaccine in adults 55 years of age or younger, polysaccharide vaccines are an acceptable alternative for adults in this age group if the conjugated vaccine is unavailable. Since safety and efficacy of conjugate vaccines in adults older than 55 years of age have not been established to date, polysaccharide vaccines should be used for primary immunization in this group.

Infections are treated with antibiotics, particularly doxycycline, and the acute symptoms appear to respond to these drugs.

Vaccination is the only known method to prevent the development of tumors when chickens are infected with the virus. However, administration of vaccines does not prevent transmission of the virus, i.e., the vaccine is not sterilizing. However, it does reduce the amount of virus shed in the dander, hence reduces horizontal spread of the disease. Marek's disease does not spread vertically. The vaccine was introduced in 1970 and the scientist credited with its development is Dr. Ben Roy Burmester and Dr. Frank J Siccardi. Before that, Marek's disease caused substantial revenue loss in the poultry industries of the United States and the United Kingdom. The vaccine can be administered to one-day-old chicks through subcutaneous inoculation or by "in ovo" vaccination when the eggs are transferred from the incubator to the hatcher. "In ovo" vaccination is the preferred method, as it does not require handling of the chicks and can be done rapidly by automated methods. Immunity develops within two weeks.

The vaccine originally contained the antigenically similar turkey herpesvirus, which is serotype 3 of MDV. However, because vaccination does not prevent infection with the virus, the Marek's disease virus has evolved increased virulence and resistance to this vaccine. As a result, current vaccines use a combination of vaccines consisting of HVT and gallid herpesvirus type 3 or an attenuated MDV strain, CVI988-Rispens (ATCvet code: ).

In laboratory animals, prevention includes a low-stress environment, an adequate amount of nutritional feed, and appropriate sanitation measurements. Because animals likely ingest bacterial spores from contaminated bedding and feed, regular cleaning is a helpful method of prevention. No prevention methods are currently available for wild animal populations.

Common clinical signs and symptoms of Whipple's disease include diarrhea, steatorrhea, abdominal pain, weight loss, migratory arthropathy, fever, and neurological symptoms. Weight loss and diarrhea are the most common symptoms that lead to identification of the process, but may be preceded by chronic, unexplained, relapsing episodes of non-destructive seronegative arthritis, often of large joints.

Diagnosis is made by biopsy, usually by duodenal endoscopy, which reveals PAS-positive macrophages in the lamina propria containing non-acid-fast gram-positive bacilli. Immunohistochemical staining for antibodies against "T. whipplei" has been used to detect the organism in a variety of tissues, and a PCR-based assay is also available. PCR can be confirmatory if performed on blood, vitreous fluid, synovial fluid, heart valves, or cerebrospinal fluid. PCR of saliva, gastric or intestinal fluid, and stool specimens is highly sensitive, but not specific enough, indicating that healthy individuals can also harbor the causative bacterium without the manifestation of Whipple's disease, but that a negative PCR is most likely indicative of a healthy individual.

Endoscopy of the duodenum and jejunum can reveal pale yellow shaggy mucosa with erythematous eroded patches in patients with classic intestinal Whipple's disease, and small bowel X-rays may show some thickened folds. Other pathological findings may include enlarged mesenteric lymph nodes, hypercellularity of lamina propria with "foamy macrophages", and a concurrent decreased number of lymphocytes and plasma cells, per high power field view of the biopsy.

A D-Xylose test can be performed, which is where the patient will consume 4.5g of D-xylose, a sugar, by mouth. The urine excretion of D-Xylose is then measured after 5 hours. The majority of D-Xylose is absorbed normally, and should be found in the urine. If the D-Xylose is found to be low in the urine, this suggests an intestinal malabsorption problem such as bacterial overgrowth of the proximal small intestine, Whipple's Disease, or an autoimmune with diseases such as Celiac's Disease (allergy to gluten) or Crohn's Disease (autoimmune disease affecting the small intestine). With empiric antibiotic treatment after an initial positive D-Xylose test, and if a follow-up D-Xylose test is positive (decreased urine excretion) after antibiotic therapy, then this would signify it is not bacterial overgrowth of the proximal small intestine. Since Whipple's disease is so rare, a follow-up positive D-Xylose test more likely indicates a non-infectious etiology and more likely an autoimmune etiology. Clinical correlation is recommended to rule out Whipple's disease.

According to a recent study, the main risk factors for RA-ILD are advancing age, male sex, greater RA disease activity, rheumatoid factor (RF) positivity, and elevated titers of anticitrullinated protein antibodies such as anticyclic citrullinated peptide. Cigarette smoking also appears to increase risk of RA-ILD, especially in patients with human leukocyte antigen DRB1.

A recently published retrospective study by a team from Beijing Chao-Yang Hospital in Beijing, China, supported three of the risk factors listed for RA-ILD and identified an additional risk factor. In that study of 550 RA patients, logistic regression analysis of data collected on the 237 (43%) with ILD revealed that age, smoking, RF positivity, and elevated lactate dehydrogenase closely correlated with ILD.

Recent studies have identified risk factors for disease progression and mortality. A retrospective study of 167 patients with RA-ILD determined that the usual interstitial pneumonia (UIP) pattern on high-resolution computed tomography (HRCT) was a risk factor for progression, as were severe disease upon diagnosis and rate of change in pulmonary function test results in the first 6 months after diagnosis.

A study of 59 RA-ILD patients found no median survival difference between those with the UIP pattern and those without it. But the UIP group had more deaths, hospital admissions, need for supplemental oxygen, and decline in lung function.

Currently, antibiotic drugs such as penicillin or tetracycline are the only effective methods for disease treatment. Within wild populations, disease control consists of reducing the amount of bacterial spores present in the environment. This can be done by removing contaminated carcasses and scat.

No serious long-term effects are known for this disease, but preliminary evidence suggests, if such symptoms do occur, they are less severe than those associated with Lyme disease.

Treatment is with penicillin, ampicillin, tetracycline, or co-trimoxazole for one to two years. Any treatment lasting less than a year has an approximate relapse rate of 40%. Recent expert opinion is that Whipple's disease should be treated with doxycycline with hydroxychloroquine for 12 to 18 months. Sulfonamides (sulfadiazine or sulfamethoxazole) may be added for treatment of neurological symptoms.

The differential diagnosis of Rosai–Dorfman disease includes both malignant and nonmalignant diseases, such as granulomatosis with polyangiitis, Langerhans cell histiocytosis, Langerhans cell sarcoma, lymphoma, sarcoidosis, and tuberculosis. The disease is diagnosed by biopsy of affected tissues. Microscopic examination of stained specimens will show histiocytes with lymphocytes and possibly other types of cells trapped within them, a phenomenon known as emperipolesis. Upon immunohistochemical staining, the histiocytes will be positive for S100, CD68, and CD163 but negative for CD1a.

There is no vaccine for SVD. Prevention measures are similar to those for foot-and-mouth disease: controlling animals imported from infected areas, and sanitary disposal of garbage from international aircraft and ships, and thorough cooking of garbage. Infected animals should be placed in strict quarantine. Eradication measures for the disease include quarantining infected areas, depopulation and disposal of infected and contact pigs, and cleaning and disinfecting

contaminated premises.

The exact cause of rheumatoid lung disease is unknown. However, associated factors could be due largely to smoking. Sometimes, the medicines used to treat rheumatoid arthritis, especially methotrexate, may result in lung disease.

Prevention's:

- Stop smoking: Chemicals found in cigarettes can irritate already delicate lung tissue, leading to further complications.

- Having regular checkups: The doctor could listen to lungs and monitor breathing, because lung problems that are detected early can be easier to treat.

Some patients have no symptoms, spontaneous remission, or a relapsing/remitting course, making it difficult to decide whether therapy is needed. In 2002, authors from Sapienza University of Rome stated on the basis of a comprehensive literature review that "clinical observation without treatment is advisable when possible."

Therapeutic options include surgery, radiation therapy, and chemotherapy. Surgery is used to remove single lymph nodes, central nervous system lesions, or localized cutaneous disease. In 2014, Dalia and colleagues wrote that for patients with extensive or systemic Rosai–Dorfman disease, "a standard of care has not been established" concerning radiotherapy and chemotherapy.

Morbidity and mortality range from both extremes as the significance correlate with the underlying systemic disease.

Pogosta disease is a viral disease, established to be identical with other diseases, Karelian fever and Ockelbo disease. The names are derived from the words Pogosta, Karelia and Ockelbo, respectively.

The symptoms of the disease include usually rash, as well as mild fever and other flu-like symptoms; in most cases the symptoms last less than 5 days. However, in some cases, the patients develop a painful arthritis. There are no known chemical agents available to treat the disease.

It has long been suspected that the disease is caused by a Sindbis-like virus, a positive-stranded RNA virus belonging to the Alphavirus genus and family Togaviridae. In 2002 a strain of Sindbis was isolated from patients during an outbreak of the Pogosta disease in Finland, confirming the hypothesis.

This disease is mainly found in the Eastern parts of Finland; a typical Pogosta disease patient is a middle-aged person who has been infected through a mosquito bite while picking berries in the autumn. The prevalence of the disease is about 100 diagnosed cases every year, with larger outbreaks occurring in 7-year intervals.

Swine vesicular disease (SVD) is an acute, contagious viral disease of swine caused by the swine vesicular disease virus, an enterovirus. It is characterized by fever and vesicles with subsequent ulcers in the mouth and on the snout, feet, and teats. The pathogen is relatively resistant to heat, and can persist for a long time in salted, dried, and smoked meat products. Swine vesicular disease does not cause economically-important disease, but is important due to its similarity to foot-and-mouth disease.

All patients with symptomatic cryoglobulinemia are advised to avoid, or protect their extremities, from exposure to cold temperatures. Refrigerators, freezers, and air-conditioning represent dangers of such exposure.

Grover's may be suspected by its appearance, but since it has such a characteristic appearance under the microscope a shave skin or punch biopsy is often performed.

Individuals found to have circulating cryoglobulins but no signs or symptoms of cryoglobulinemic diseases should be evaluated for the possibility that their cryoglobulinemia is a transient response to a recent or resolving infection. Those with a history of recent infection that also have a spontaneous and full resolution of their cryoglobulinemia need no further treatment. Individuals without a history of infection and not showing resolution of their cryoglobulinemia need to be further evaluated. Their cryoglobulins should be analyzed for their composition of immunoglobulin type(s) and complement component(s) and examined for the presence of the premalignant and malignant diseases associated with Type I disease as well as the infectious and autoimmune diseases associated with type II and type III disease. A study conducted in Italy on >140 asymptomatic individuals found five cases of hepatitis C-related and one case of hepatitis b-related cryoglobulinemia indicating that a complete clinical examination of asymptomatic individuals with cryoglobulinemia offers a means for finding people with serious but potentially treatable and even curable diseases. Individuals who show no evidence of a disease underlying their cryoglobulinemia and who remain asymptomatic should be followed closely for any changes that may indicate development of cryoglobulinemic disease.

There seems to be beneficial responses to clindamycin therapy as the lesions regress. This leads to the hypothesis that microorganisms may be playing a role in the initial stages of Kyrle disease.

A family with Kyrle disease were examined which their skin lesions were benign. However, when three of the young adult members were closely examined, they had posterior subcapsular cataracts and two of those three developed multiple tiny yellow-brown anterior stromal corneal opacities. In order to determine if there is any correlation between Kyrle disease and the ocular observations, more cases of Kyrle disease are to be analyzed.

All in all, since Kyrle disease is relatively rare, more cases need to be studied and analyzed in order to understand the underlying pathogenesis and to improve the management of the disease.

Chronic Lyme disease is a generally unrecognised diagnosis that encompasses "a broad array of illnesses or symptom complexes for which there is no reproducible or convincing scientific evidence of any relationship to "B. burgdorferi" infection." There is no clinical evidence that "chronic" Lyme disease is caused by a persistent infection. It is distinct from post-treatment Lyme disease syndrome, a set of lingering symptoms which may persist after successful treatment of infection with Lyme spirochetes. The symptoms of "chronic Lyme" are generic and non-specific "symptoms of life".

A number of alternative treatments are promoted for "chronic Lyme disease", of which possibly the most controversial and harmful is long-term antibiotic therapy, particularly intravenous antibiotics. Most medical authorities advise against long-term antibiotic treatment for Lyme disease, though they agree that some patients do experience lingering symptoms. Following disciplinary proceedings by State medical licensing boards in the United States, a subculture of "Lyme literate" physicians has successfully lobbied for specific legal protections, exempting them from the standard of care and Infectious Diseases Society of America treatment guidelines. This "troubling" political interference in medical care has been criticised as an example of "legislative alchemy", the process whereby pseudomedicine is legislated into practice.