The antivenom therapy in India is bitten by deficiencies: study

BENGALURU: A new study by scientists from the Indian Institute of Science (IISc) in collaboration with the Gerry Martin Project and the Madras Crocodile Bank Trust and Center for Herpetology shows that commercially available antivenoms in India may be ineffective in treating bites from Certain medications of medical importance. Neglected snakes

“These snakes are those whose bites are harmful to humans, but are poorly studied. India is the world capital of snake bites, says Kartik Sunagar, an assistant professor at the IISc Center for Ecological Sciences and lead author of the study published in PLoS Neglected Tropical Diseases.

The study estimates that about 46,000 people die each year and 1.4 lakh people become disabled in the country due to snake bites. The only scientifically validated treatment for snake bites is the use, for which manufacturing protocols have remained unchanged for more than a century.

In India, a polyvalent antivenom is produced against the so-called snakes of the big four: the eyeglass viper, the common krait, Russell's viper, and the viper with saw scales.

However, in addition to these snakes, India is home to many other species of venomous snakes that have the potential to cause fatal, even fatal, bites: about 60 of the 270 species of Indian snakes are considered medically important. But specific antivenoms do not occur against these species; on the other hand, the antiveneno of the four great ones is used habitually to treat the bites of all the snakes, reads in a statement of IISc.

To better understand the consequences of using polyvalent antivenom to treat all snake bites, the researchers conducted a double study. In the first part, they characterized the poisons of the main unattended, but medically important, Indian snakes: their composition, pharmacological activities and potencies. These snakes included the Sochurek viper, the Sind krait, the krait with a band and two populations of monocular cobras, as well as their closest relatives of the four large ones (scaly viper, common krait and eyeglass cobra).

The results revealed dramatic differences in the venom compositions of these snakes. They also showed that the composition of the poison differed between geographically separated populations of the same species.

“For example, a great variation was observed in the poisons of two populations of the same species of monocular cobra from West Bengal and Arunachal Pradesh. It was discovered that the former was highly neurotoxic (directed to the nervous system) while the latter was rich in cytotoxins (directed to cells and tissues), ”Sunagar explained.

In the second part of the study, the research team evaluated the effectiveness of marketed antivenoms for treating snake bites of abandoned species. Again, the results were surprising. The researchers found that the antivenoms were highly inefficient to overcome the effects of the toxin, and one of the antivenoms was completely ineffective against the Arunachal Pradesh monocular cobra in a mouse model.

Surprisingly, this widely marketed commercial antivenom did not even neutralize the venom of one of the 'big four' snakes of northern India: the common krait.

The study also found that Sind krait venom from western India is 40 times more potent than that of the spectacled cobra, which makes it the most toxic Indian snake. Unfortunately, the polyvalent antivenom also fails to effectively neutralize the venom of this species, says Sunagar.

The main conclusion of the study for antivenom manufacturers, public health officials and policy makers, according to Sunagar, is a pressing need to develop region-specific snake bite therapies for the many forgotten species.

The document also provides future instructions for Indian antivenom manufacturers to improve the effectiveness of their antivenoms marketed in India. As a step forward, we have also started collaborations with some of the Indian antivenom manufacturers to produce these regionally effective antivenoms, he adds.