Latest news with #Simuliidae
News18
26-04-2025
- Health
- News18
Blood-Sucking Fly That Can Cause Human Blindness Identified In Darjeeling, Kalimpong
Last Updated: Onchocerciasis, commonly known as 'river blindness,' is caused by the parasitic worm Onchocerca volvulus. The worm is carried by black flies. The Zoological Survey of India (ZSI) has discovered a species of blood-sucking fly that can cause human blindness. 'Black" flies, also referred to as 'pipsa" or 'potu" flies by the locals, are found in the areas of the Darjeeling and Kalimpong districts of West Bengal. These flies are carriers of worms known as Onchocerca volvulus, which cause blindness in humans. According to the World Health Organization (WHO), onchocerciasis, commonly known as 'river blindness", is caused by the parasitic worm Onchocerca volvulus. It is transmitted to humans by the repeated bites of infected blackflies that breed in flowing rivers. 'These black flies of the Simuliidae family are extremely small. They are barely noticeable to the naked eye. Before one realises it, the fly has already sucked blood and left. Many species in this family look almost identical externally. In scientific terms, distinguishing between two different species of Simuliidae flies based on external characteristics is quite difficult and time-consuming. Sometimes, accurate species identification is not even possible," Dr Dhriti Banerjee, Director, Zoological Survey of India, was quoted as saying by The Indian Express. According to the report by the Indian Express, Dr Atanu Naskar, the officer-in-charge and scientist at the Diptera division of the Zoological Survey of India, informed that a research was conducted across eight areas of the Darjeeling and Kalimpong districts. The researchers collected the DNA samples and then barcoded the DNA to identify the fly. While there has been no report of any disease caused by these flies as of now, Dr Dhriti Banerjee told Indian Express that the people in these areas remain at risk of blindness, as these places witness good numbers of tourists who might unknowingly get bitten. First Published: April 26, 2025, 23:45 IST
Indian Express
26-04-2025
- Health
- Indian Express
ZSI study finds human blindness-causing blackfly in rivers flowing through Darjeeling, Kalimpong
The Zoological Survey of India (ZSI) has recently spotted blackflies, which serve as carriers of a worm causing human blindness, in many rivers flowing through the northern parts of West Bengal. Locally called 'pipsa' or 'potu', the blood-sucking flies were found in rivers in areas such as Darjeeling and Kalimpong that serve as the insect's breeding grounds. The finding raises concern as the areas draw many tourists throughout the year. 'Whether Darjeeling or Kalimpong, both places are favourites among Bengalis on the tourism map, making them socio-economically significant. People visit these places throughout the year. Visitors may unknowingly get bitten by these blood-sucking flies while enjoying themselves. Although local people are more vulnerable to these flies, the risk of blindness remains a concern,' Dr Dhriti Banerjee, Director of the Zoological Survey of India. ZSI scientists have, however, confirmed that no individual has so far been diagnosed with the infection called 'river blindness' in the region. According to the World Health Organization (WHO), the blindness caused by the worm called Onchocerca volvulus is among the most neglected tropical diseases. 'When these blood-sucking blackflies bite humans, the worms enter the human body from the fly. Initially, the worms form nodules under the skin. As they grow, they travel through the bloodstream to the eyes, ultimately resulting in blindness,' explained a scientist. The first step towards protecting people from the infection is to identify and control the vector – the black fly, and therefore, better identification of the disease carrier is essential for improved treatment, said the scientists at the Diptera division of the ZSI in a statement. 'These black flies of the Simuliidae family are extremely small. They are barely noticeable to the naked eye. Before one realises it, the fly has already sucked blood and departed. Many species in this family look almost identical externally. In scientific terms, distinguishing between two different species of Simuliidae flies based on external characteristics is quite difficult and time-consuming. Sometimes accurate species identification is not even possible,' said Dr Banerjee. Amid rising health concerns posed by the presence of the blackfly, researchers from the Diptera division have used DNA from these flies as a means of identification. The method employed for identifying the flies is called DNA barcoding. Dr Atanu Naskar, scientist at the ZSI's Diptera division, revealed that they conducted their research in eight locations across Darjeeling and Kalimpong districts of West Bengal, which are part of the Central Himalayan region, and collected blackfly samples. After preliminary segregation based on external characteristics, DNA barcoding methods were used to identify the species. Ark Mukherjee, a senior research fellow at the Zoological Survey of India and one of the researchers involved in the blackfly study, explained, 'First, DNA was collected from the legs of the blackfly samples, and then that DNA was barcoded.'
