Onchocerciasis- River Blindness

  • ZSI Study & DNA Barcoding: The Zoological Survey of India (ZSI) used DNA barcoding to accurately identify blackfly species in the central Himalayas, the vectors of Onchocerca volvulus, the parasitic worm that causes river blindness.
  • Why it matters: Accurate blackfly identification is crucial for effective disease control and vector management strategies, particularly in vulnerable areas like the Himalayas.
  • River Blindness (Onchocerciasis): It’s a neglected tropical disease (NTD) caused by Onchocerca volvulus, transmitted through blackfly bites.
  • Symptoms & Impact: Causes intense itching, skin disfigurement, and can lead to permanent blindness. It’s second only to trachoma as a cause of infection-related blindness globally.
  • Global Impact: Primarily affects rural populations in sub-Saharan Africa, Yemen, and parts of Latin America.
  • Treatment: Mass drug administration (MDA) with ivermectin is the primary treatment.
  • WHO Focus: The World Health Organization (WHO) considers river blindness one of the most neglected tropical diseases.
  • Identification Challenges: Blackfly species are tiny and difficult to distinguish based on external characteristics alone.
  • Himalayan Region: The study focused on blackflies collected from the Kalimpong and Darjeeling areas in West Bengal, where the flies are known locally as “pipsa” or “potu”.
  • Risk to Visitors: The risk of river blindness transmission exists not only for locals but also for visitors to areas like Darjeeling and Kalimpong.