obsolete avian tuberculosis

Avian Tuberculosis in Birds: A Historical Perspective

Avian tuberculosis, also known as avian mycobacteriosis, was a significant disease affecting companion, captive exotic, wild, and domestic birds in the past. The disease was caused by infection with Mycobacterium avium subsp. avium or other related species.

Characteristics of Obsolete Avian Tuberculosis

• Chronic and Progressive Wasting: Avian tuberculosis was characterized by a chronic and progressive wasting and weakness in infected birds [1].
• Granulomatous Lesions: The disease was marked by the formation of granulomatous lesions in various organs, including the viscera, liver, spleen, and lungs [2].
• Transmission: Avian tuberculosis could be transmitted through direct contact with infected birds or contaminated environments [3].

Impact on Bird Populations

• Significant Disease in Old Flocks: In old flocks, avian tuberculosis was a very common disease, affecting many bird populations [7].
• Public Health Significance: The disease had public health significance due to its potential transmission to humans and other animals [11].

Comparison with Modern Avian Tuberculosis

While the characteristics of obsolete avian tuberculosis remain similar to those of modern avian tuberculosis, there are some differences in terms of incidence and prevalence. In recent years, the introduction of novel poultry husbandry practices has led to a decline in the incidence of avian tuberculosis in domestic poultry [11].

However, avian tuberculosis remains an important disease affecting companion, captive exotic, wild, and domestic birds worldwide, with Mycobacterium avium being the most significant cause of poultry disease [12].

References

[1] SRIVASTAVA, V. (2017). Avian Tuberculosis in Birds: A Review.

[2] Snyder, S. B. (Cited by 1). Abstract: A whooping crane (Grns americana) confirmed as suffering from Mycobacterium avium infection was treated for 1 year.

[3] Wigle, W. L. (2000). Pulmonary involvement is not a significant feature of avian tuberculosis but does occurs occasionally.

[7] Description of the disease: Avian tuberculosis, or avian mycobacteriosis, is an important disease

Obsolescence of Avian Tuberculosis

Avian tuberculosis, also known as avian mycobacteriosis, was once a significant disease affecting domestic and wild birds. However, with advancements in veterinary medicine and improved biosecurity measures, the incidence of this disease has decreased significantly.

Historical Signs and Symptoms

In the past, avian tuberculosis presented with a range of clinical signs and symptoms, including:

• Weight loss: Progressive weight loss was a common sign, even when birds were eating normally [13][14].
• Lethargy: Affected birds were often weak and lethargic, with poor or ruffled plumage [14].
• Chronic wasting: Birds would become emaciated, often exhibiting a prominent keel [14].
• **Abdominal dist

Diagnostic Tests for Obsolete Avian Tuberculosis

Avian tuberculosis, caused by Mycobacterium avium complex (MAC), has been a significant concern in the poultry industry. However, with advancements in diagnostic techniques and changes in disease prevalence, some tests may be considered obsolete. Here are some diagnostic tests that were once used to detect avian tuberculosis:

• Culture-based methods: Traditional culture-based methods, such as solid media and liquid culture, were widely used to isolate MAC from clinical samples (1). However, these methods can be time-consuming and require specialized equipment.
• Serological tests: Serological tests, including enzyme-linked immunosorbent assay (ELISA) and complement fixation test (CFT), were used to detect antibodies against MAC in the serum of infected birds (2). While these tests are still useful for some applications, they have limitations in terms of sensitivity and specificity.
• Histopathology: Histopathological examination of tissue samples was also used to diagnose avian tuberculosis. This method involves examining tissue sections under a microscope for characteristic lesions and MAC bacteria (3).

Modern Diagnostic Approaches

In recent years, more modern and efficient diagnostic approaches have been developed:

• Molecular techniques: Molecular techniques, such as polymerase chain reaction (PCR) and real-time PCR, have become the gold standard for diagnosing avian tuberculosis. These methods can detect MAC DNA in clinical samples with high sensitivity and specificity (4).
• Immunological tests: Immunological tests, including ELISA and immunochromatographic assays, are still used to detect antibodies against MAC. However, these tests are often used in combination with molecular techniques for confirmatory testing.
• Whole-genome sequencing: Whole-genome sequencing has been used to identify MAC strains and understand their genetic diversity (5).

Conclusion

While some diagnostic tests may be considered obsolete due to advancements in technology and changes in disease prevalence, others remain useful for specific applications. A combination of modern molecular techniques and immunological tests provides a robust approach for diagnosing avian tuberculosis.

References:

1. Culture-based methods: [1] (Search result 1)
2. Serological tests: [2] (Search result 2)
3. Histopathology: [3] (Search result 3)
4. Molecular techniques: [4] (Search result 4)
5. Whole-genome sequencing: [5] (Search result 5)

Treatment Options for Avian Tuberculosis

Avian tuberculosis, caused by Mycobacterium avium complex (MAC), has been a significant concern in the veterinary field, particularly in domestic and pet birds. While the disease is still prevalent, treatment options have evolved over time.

• Historical Treatment: In the past, para-aminosalicylic acid (PAS) was one of the first effective treatments for TB [7]. However, its use has declined due to concerns about toxicity and resistance.
• Modern Treatment: Today, a combination of antibiotics is commonly used to treat avian tuberculosis. The most effective drug used in treatment is azithromycin [12], although it may not be effective against all strains of M. avium complex due to the development of antibiotic resistance.

Treatment Duration and Regimens

The appropriate length of time needed for successful treatment of avian mycobacteriosis is unknown, with treatment durations ranging from 1 to 18 months [11]. Treatment duration is likely dependent on factors such as severity of infection, sensitivity to drug therapy, compliance with drug therapy, and possibly the strain of mycobacteria involved.

Multiple-Drug Therapy

Multiple-drug therapy is generally more successful against these organisms than single-drug therapy. Doxycycline and rifampin are a common combination used in treatment [4].

Challenges in Treatment

Treatment for avian mycobacteriosis is still in its infancy, and based on extrapolations from human medicine. The optimum drug choice, dose, or length of treatment has yet to be determined for most exotic animal species [13].

Differential Diagnoses for Obsolete Avian Tuberculosis

Obsolescence in medical terminology refers to a condition or disease that has become outdated, and its diagnosis is no longer relevant in modern practice. However, understanding the differential diagnoses for obsolete avian tuberculosis can provide valuable insights into the historical context of this disease.

Historical Context Avian tuberculosis was once considered a significant disease affecting domestic and pet birds worldwide [11]. The primary causative agent was Mycobacterium avium, belonging to serotypes 1, 2, 3, and 6 (genotype IS901+ and IS1245+) [11].

Differential Diagnoses

In cases where avian tuberculosis is suspected but the disease has become obsolete, the following conditions should be considered in the differential diagnosis:

• Mycoplasma spp. infection: This bacterial infection can cause similar symptoms to avian tuberculosis, such as respiratory issues and weight loss [14].
• Other bacterial infections: Various other bacteria, including those causing cat-scratch disease, infectious mononucleosis, toxoplasmosis, brucellosis, and malignancy (lymphoma), should be ruled out in the differential diagnosis [5].
• Poxvirus infection: Although rare, poxvirus can cause symptoms similar to avian tuberculosis, such as skin lesions and respiratory issues [14].

Key Points

• Obsolete avian tuberculosis was once a significant disease affecting domestic and pet birds worldwide.
• The primary causative agent was Mycobacterium avium.
• In cases where avian tuberculosis is suspected but the disease has become obsolete, consider the following differential diagnoses:
  • Mycoplasma spp. infection
  • Other bacterial infections (e.g., cat-scratch disease, infectious mononucleosis, toxoplasmosis, brucellosis, and malignancy)
  • Poxvirus infection

References

[1] Cooper, J. E. (1985). Avian tuberculosis in raptors: A review of the literature.

[2] Thavagnanam, S. (2006). Mycobacteriosis in birds: A review of the literature.

[3] Chavarria, M. (2018). Mycobacterium celatum infection in birds: A case report.

[4] Snyder, SB. (no date available). Mycobacteriosis or other granulomatous diseases were differential diagnoses.

[5] Srivastava, V. (2017). Differential diagnosis helps in differentiating two or more strains/conditions.

[6] The necropsy chapter underwent major revision to include the differential diagnosis procedure which goes on when a post-mortem examination is being performed.

[7] M Chavarria · 2018 · Cited by 12. Diagnostic approaches to avian tuberculosis - Volume 73 Issue 4.

[8] Avian tuberculosis tends to be a chronic condition, and affected birds often do not demonstrate any clinical signs until death.

[9] Transmission is via ingestion of contaminated feed, water, and exposure to contaminated feces from infected birds.

[10] Differential diagnoses include infection with Mycoplasma spp. or other bacteria, and more rarely poxvirus, flagellated ...