Model Answer
0 min readIntroduction
Mediterranean fever, also known as Louping illness, is a tick-borne disease affecting primarily sheep, goats, and wild ruminants. Caused by *Coxiella burnetii*, the same bacterium responsible for Q fever in humans, it is prevalent in Mediterranean regions and other areas with suitable tick vectors. The disease manifests with fever, joint pain, and various neurological signs, leading to significant economic losses in livestock farming. Understanding its diagnosis, treatment, and prevention is crucial for effective disease management and public health protection, given its zoonotic potential.
What is Mediterranean Fever?
Mediterranean fever (Louping illness) is a bacterial infectious disease caused by *Coxiella burnetii*. It is a zoonotic disease, meaning it can be transmitted from animals to humans. The primary vectors are ticks, particularly *Ixodes ricinus* and *Dermacentor nuttalli*.
Diagnosis
Diagnosis relies on a combination of clinical signs, epidemiological history, and laboratory confirmation.
- Clinical Signs: Sudden onset of fever (40-42°C), joint pain (arthritis), lameness, neurological signs like ataxia (loss of coordination), and occasionally abortion in pregnant animals.
- Epidemiological History: Exposure to ticks, particularly in endemic areas.
- Laboratory Tests:
- Serology: Microimmunofluorescence (MIF) assay to detect antibodies against *C. burnetii*. A four-fold increase in antibody titer between acute and convalescent samples confirms the diagnosis.
- PCR: Polymerase Chain Reaction (PCR) to detect *C. burnetii* DNA in tissue samples (e.g., joint fluid, placenta).
- Culture: Difficult and rarely performed due to the fastidious nature of the bacterium.
- Antibiotics: Doxycycline is the most commonly used antibiotic, although efficacy is variable. Macrolides (e.g., azithromycin) may be considered.
- Supportive Care: Fluid therapy to manage dehydration, pain relief, and supportive nutrition.
- Early Diagnosis: Crucial for improving prognosis.
- Tick Control:
- Acaricides: Application of pesticides to control ticks on livestock and in the environment.
- Pasture Management: Reducing tick habitats by clearing brush and managing vegetation.
- Strategic Grazing: Avoiding grazing in heavily infested areas.
- Vaccination: A commercial vaccine is available in some regions, providing effective protection against infection. Regular booster vaccinations are required.
- Biosecurity: Isolation of newly purchased animals to prevent disease introduction.
Treatment
Treatment is often challenging and primarily supportive, as *C. burnetii* is resistant to many common antibiotics.
Prevention
Prevention focuses on controlling tick populations and vaccination.
| Aspect | Details |
|---|---|
| Causative Agent | *Coxiella burnetii* |
| Vectors | Ixodes ricinus, Dermacentor nuttalli |
| Primary Hosts | Sheep, goats, wild ruminants |
| Key Symptoms | Fever, arthritis, ataxia |
Conclusion
Mediterranean fever remains a significant concern for livestock production and public health due to its zoonotic potential and challenging treatment. Early and accurate diagnosis through a combination of clinical signs and laboratory testing is paramount. Integrated prevention strategies focusing on tick control and vaccination, combined with robust biosecurity measures, are essential to mitigate the disease's impact. Continued research into novel diagnostics and therapeutics is also warranted to improve disease management.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.