Human Blindness-Causing Blackflies Found in Darjeeling: Study
A recent study conducted by the Zoological Survey of India (ZSI) has found blackflies, the carriers of the worm Onchocerca volvulus that causes human blindness, in rivers in Darjeeling and Kalimpong districts of West Bengal. The discovery has raised concerns about the risk of blindness in the region, particularly in areas where the flies are most active.
According to the study, the blackflies were identified using DNA barcoding, a technique that involves analyzing the genetic material of an organism to identify its species. The researchers found that the blackflies were present in several rivers in Darjeeling and Kalimpong, including the Teesta River, the Mahananda River, and the Jaldhaka River.
The blackflies, also known as Simulium species, are notorious for their blood-sucking habits. When they bite humans, they release the Onchocerca volvulus worms into the bloodstream. These worms travel to the eyes, where they cause inflammation and scarring, leading to blindness.
The study’s findings are particularly concerning for the people living in the affected areas, as the blackflies are most active during the monsoon season, which typically runs from June to September. This is also the time when people are most likely to be outdoors, increasing their exposure to the flies.
The Onchocerca volvulus worm is responsible for causing river blindness, a disease that affects millions of people worldwide. In India, the disease is most prevalent in the northeastern states, including West Bengal, Assam, and Bihar.
The ZSI study is significant because it provides conclusive evidence of the presence of blackflies in Darjeeling and Kalimpong. Previous studies had suggested the presence of the flies, but this is the first time that DNA barcoding has been used to confirm the identification of the species.
The study’s findings have important implications for public health in the region. The presence of blackflies means that people living in the affected areas are at risk of contracting river blindness, which can lead to severe and permanent vision loss.
To mitigate the risk of blindness, it is essential to take measures to control the spread of the blackflies. This can be achieved through a combination of vector control measures, such as using insecticides and biological control methods, as well as improving access to healthcare and providing regular eye examinations to detect the disease early.
The ZSI study highlights the need for continued research and surveillance to monitor the spread of blackflies and the disease they carry. It also underscores the importance of public health education and awareness, particularly in areas where the flies are most active.
In conclusion, the discovery of human blindness-causing blackflies in Darjeeling and Kalimpong districts of West Bengal is a significant finding that has important implications for public health in the region. It is essential to take measures to control the spread of the blackflies and to provide access to healthcare and eye examinations to detect the disease early. By working together, we can reduce the risk of blindness and promote public health in the region.
