Rift Valley Fever (RVF)

News: Recently, WHO confirmed an outbreak of Rift Valley Fever (RVF) affecting Mauritania and Senegal, resulting in over 404 human cases and 42 deaths.

About Rift Valley Fever (RVF)

• RVF is a viral zoonotic disease that affects both animals and humans.
• Caused by : The disease is caused by a Phlebovirus belonging to the Phenuiviridae family.
• It primarily infects animals such as sheep, goats, cattle, and camels.
• Transmission
  • Humans become infected through bites of infected mosquitoes or contact with blood, organs, or raw milk from infected animals.
  • There is no evidence of human-to-human transmission.
• Incubation period: It is usually begin 2–6 days after exposure.
• Symptoms
  • About 90% develop a mild, flu-like illness with high fever, headache, weakness, backache, and muscle and joint pain, sometimes with nausea, vomiting, and light sensitivity.
  • Severe disease is uncommon but includes:
    • Ocular disease (0.5–2%) causing blurred vision, floaters, eye pain, and possible permanent loss;
    • Meningoencephalitis (<1%) with confusion, dizziness, seizures, or coma; and
    • A haemorrhagic form (<1%) with jaundice, bleeding, and liver failure, carrying ~50% fatality.
• Diagnosis
  • Diagnosing RVF is challenging because it mimics malaria, typhoid, and other febrile illnesses.
  • Confirmation requires laboratory testing using molecular or serological methods under high biosafety precautions.
• Treatment
  • No specific antiviral treatment or licensed human vaccine is available.
  • Animal vaccination is useful between outbreaks but not during them.
• Global classification
  • It is recognized by the World Organization for Animal Health as a notifiable animal disease.
  • It listed by WHO as a priority pathogen with epidemic potential.
• Indian perspective
  • India has not reported any Rift Valley Fever outbreak till date.
  • It is classified as an exotic zoonosis under India’s One Health surveillance framework.