seresto collars
Americans have bought about 34 million Seresto flea and tick collars since 2013; (photo/LisaCarter via Shutterstock)

Seresto Flea Collar Linked to 2,500 Pet Deaths; Feds Advise Recall

Seresto flea and tick collars are widely popular in the U.S. But a congressional report links them to widespread pet deaths, diseases, and injuries.

The company that makes Seresto flea and tick collars should voluntarily recall them, says the U.S. House Committee on Oversight and Reform.

That’s because its research linked the popular collars to over 2,500 pet deaths, leaving families across the country without their beloved pets. And the committee found almost 100,000 reported incidents of what the Environmental Protection Agency (EPA) calls “unexpected effects from the use of a pesticide.”

The 23-page report recommends a sweeping product recall but points even more decisively toward oversight by the EPA.

Yesterday, Subcommittee Chair @CongressmanRaja heard directly from some of these pet owners.

— Oversight Committee (@OversightDems) June 16, 2022

Among other allegations, it says the EPA allowed the collar to stay on the market despite identifying the danger to pets and owners as early as 2015. And while Canada’s Pest Management Regulatory Agency (PMRA) banned the Seresto collars, the EPA continued to allow them in the U.S. despite similar findings.

According to the report, American consumers have bought about 34 million Seresto flea and tick collars since their release in 2013. The collar’s popularity stemmed partly from the fact that, as advertised, it can prevent flea and tick problems for 8 months — eliminating the need for owners to re-apply treatment monthly, as is common in other products.

Data Says Collars Can Cause Pet Lesions, Vomiting, and Owner Side Effects

Elanco Animal Health currently handles manufacturing for Seresto collars. That’s been the case since it purchased previous Seresto owner Bayer Animal Health in 2020.

The report relies on the PMRA’s research in recommending the recall. The agency found it “posed too great a risk to pets and their owners to be sold in Canada” after analyzing symptoms experienced by hundreds of pets. Based on 961 “death” and “major” pet incidents on which Bayer provided “enhanced data,” the PMRA found the Seresto collar “probably or possibly” caused 737 (77%) of them, the report said.

Per the documents, observed symptoms included skin lesions and irritated skin, which sometimes covered large areas of a pet’s body and did not resolve after owners removed the collar. According to the panel, other symptoms include lethargy, abnormal behavior, excessive grooming and vocalization, vomiting, diarrhea, and anorexia.

“These troubling symptoms appeared shortly after use of the Seresto collar began, mostly within the first month,” the report said. “Many pet owners reacted by removing their pets’ collars early,” it stated.

The report added that pet owners also reportedly experienced side effects. These included skin and immune disorders, plus respiratory, neurological, and digestive impacts. Throat irritation, dizziness, and nausea all occurred, it said.

Comparing Seresto’s active ingredients to other flea treatments’ lists, the brand uses a pesticide called flumethrin (a tick killer and repellent). No other major flea and tick treatment such as K9 Advantix, NexGuard, or Sentinel Spectrum uses it. Seresto and K9 Advantix do both utilize imidacloprid (a neural disruptor for fleas), but Seresto’s collar contains a higher percentage.

Elanco Responds

Meanwhile, Elanco seeks to downplay the claims. During a hearing on Wednesday, Elanco Animal Health CEO Jeffrey Simmons maintained that the collar is safe.

He pointed out that the EPA approved it after it underwent more than 80 safety, toxicity, and efficacy studies.

“Adverse event reports aren’t proof of causation,” Simmons said in the hearing. “We haven’t found a single death due to the ingredients in the collar.”

Elanco said it received just over 17 incident reports for every 1,000 collars sold in 2021. The company told CBS MoneyWatch that an analysis of all such reports between 2013 and 2021 shows “no established link between the active ingredients in Seresto and pet death.”

Thus, it concluded, “[g]iven the robust scientific evidence for Seresto’s strong safety profile, we are proud to stand behind the product as an important tool to protect pets from fleas and ticks and the damaging diseases they carry.”

Tips for Camping with Dogs - Eureka Midori Tent
How To: Camping With a Dog
Camping is more fun with a dog. Grab a Midori tent from Eureka! and spend the night under the stars, making memories to last a lifetime. Read more…

Report Calls for EPA to Take Action

According to the report, the EPA’s 2015 investigation into the Seresto collars concluded that they “ranked #1 by a wide margin” in terms of total incidents and “death” or “major” incidents among flea and tick products. Adjusted for sales figures, it said, it showed nearly three times the rate of total incidents, and almost five times the rate of “death” or “major” incidents, as the second-most dangerous flea and tick product.

The EPA even found the collars more dangerous than Canada’s PMRA did in 2015, per the report. Each agency reviewed the same 251 pet deaths linked to Seresto. While the PMRA ultimately attached 33% of those deaths to the collars (“possibly or probably”), the EPA found a link in 45% of the cases.

The report also details internal deliberations at the EPA following a March 2021 investigative report into the issue by USA Today. According to the documents, an inquiry prompted meetings where one EPA scientist stated that the viability of the agency’s reply would “depend[] if you want the real answer or some talking points to cover our ass for doing nothing.”

Another EPA official wrote at the time that they hoped “this time someone can blow the lid off this travesty.”

The committee concludes its report with several recommendations that put most of the onus on the EPA.

Not only does it say Elanco should initiate a voluntary recall, but it also calls for the EPA to initiate a Notice of Intent to Cancel proceedings, which would ensure that officials carried out “a comprehensive review of Seresto and its risks.” Finally, the committee says the EPA should improve its data collection procedures and tighten its pesticide safety research protocols.

Sam Anderson

Sam Anderson is a staff writer at GearJunkie, and several other All Gear websites.

He has been writing about climbing, cycling, running, wildlife, outdoor policy, the outdoor industry, vehicles, and more for 2 years. Prior to GearJunkie, he owned and operated his own business before freelancing at GearHungry. Based in Austin, Texas, Anderson loves to climb, boulder, road bike, trail run, and frequent local watering holes (of both varieties).