Seresto Flea Collars Linked to 1,700 Pet Deaths & Human Harm

Seresto Flea Collars Linked to 1,700 Pet Deaths & Human Harm

As of March 2, 2021, at least 1,700 pet deaths (dogs & cats) have been attributed to a popular flea collar under the Seresto brand (developed by Bayer and now sold by Elanco). The variety of collars used for all sizes of dogs and cats works by releasing small amounts of two pesticides (imidacloprid and flumethrinphos) onto the animal for months at a time. The pesticides were developed to kill fleas, ticks and other pests while not harming the cats, dogs and human handlers.