Crimean-Congo Haemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is a severe viral hemorrhagic fever caused by a Nairovirus belonging to the Bunyaviridae family. It’s a widespread disease, posing a significant public health threat in various regions of the world. Here’s a detailed overview:

 

Key Characteristics:

• Causative Agent:
  • The CCHF virus.
• Transmission:
  • Primarily through tick bites, particularly from Hyalomma ticks.
  • Contact with infected animal blood or tissues, especially during and after slaughter.
  • Human-to-human transmission through close contact with infected blood, secretions, organs, or other bodily fluids.
  • Nosocomial infections (hospital-acquired) due to improper sterilization of medical equipment.
• Geographical Distribution:
  • Endemic in Africa, the Balkans, the Middle East, and Asia, particularly in areas where Hyalomma ticks are prevalent.
• Severity:
  • High case fatality rate, ranging from 10% to 40%.
  • Severe hemorrhagic manifestations.

Transmission Details:

• Tick-borne Transmission:
  • Hyalomma ticks are the principal vectors.
  • Animals, including livestock, become infected through tick bites.
  • The virus circulates in animal blood, allowing ticks to become infected when they feed.
• Animal-to-Human Transmission:
  • People working with livestock, such as farmers, slaughterhouse workers, and veterinarians, are at higher risk.
  • Contact with infected animal blood or tissues during slaughter or handling.
• Human-to-Human Transmission:
  • Occurs through direct contact with infected bodily fluids.
  • Healthcare workers are at risk if they do not adhere to strict infection control measures.

Symptoms:

• Incubation Period:
  • Varies depending on the mode of transmission:
    • 1-3 days (up to 9 days) after a tick bite.
    • 5-6 days (up to 13 days) after contact with infected blood or tissues.
• Initial Symptoms:
  • Sudden onset of fever.
  • Headache.
  • Muscle aches (myalgia).
  • Dizziness.
  • Neck pain and stiffness.
  • Backache.
  • Sore eyes and photophobia (sensitivity to light).
  • Nausea, vomiting, diarrhea, abdominal pain, and sore throat.
  • Mood swings and confusion.
• Later Symptoms:
  • Sleepiness, depression, and lassitude.
  • Liver enlargement (hepatomegaly).
  • Rapid heart rate (tachycardia).
  • Enlarged lymph nodes (lymphadenopathy).
  • Petechial rash (small, pinpoint hemorrhages) on skin and mucous membranes.
  • Ecchymoses (larger areas of bruising).
  • Severe bleeding (hemorrhage).
  • Kidney and liver failure.

Diagnosis:

• Laboratory testing is essential for confirming CCHF:
  • RT-PCR (real-time polymerase chain reaction) to detect the virus’s RNA.
  • Antibody detection in blood samples.

Treatment:

• There is no specific antiviral treatment approved for CCHF.
• Supportive care is crucial:
  • Fluid and electrolyte management.
  • Blood transfusions.
  • Treatment of complications.
• The antiviral drug ribavirin has been used in some cases, with varying degrees of success.

Prevention:

• Tick Control:
  • Use of tick repellents (e.g., DEET).
  • Wearing protective clothing.
  • Controlling tick populations in livestock areas.
• Animal Handling Precautions:
  • Wearing gloves and protective clothing when handling livestock.
  • Avoiding contact with infected animal blood or tissues.
• Infection Control:
  • Strict adherence to infection control measures in healthcare settings.
  • Proper sterilization of medical equipment.
• Public Education:
  • Raising awareness about the risks of CCHF and preventive measures.
• Currently there are no widely available human vaccines.

Public Health Importance:

• CCHF has a high mortality rate.
• The potential for human-to-human transmission poses a risk of outbreaks.
• The disease is a public health concern in endemic regions.

It’s vital for healthcare professionals and the public to be aware of CCHF and take appropriate precautions.