The FDA’s Center for Veterinary Medicine and the AVMA will host a one-hour webinar titled “Resisting Resistance: FDA’s Antiparasitic Resistance Management Strategy,” on Tuesday, Oct.14, from 11 a.m. to 12 p.m. ET.

The Webinar is free and open to the public and will focus on antiparasitic resistance in U.S. grazing livestock (cattle, small ruminants, and horses), FDA’s response to this animal health threat, and the current science related to slowing down further development of resistance. Scheduled speakers include Michelle Kornele, DVM, Thomas Moskal, DVM, DACLAM, MLIS, Anna O'Brien, DVM and Aimee Phillippi-Taylor, DVM, DABVP (equine).

The issues surrounding causes of and solutions for drug-resistant parasites are complex and in some cases contentious. Back in April 2013, FDA’s Center for Veterinary Medicine (CVM) released a paper titled “Antiparasitic Resistance in Cattle and Small Ruminants in the United States: How to Detect It and What to Do About It.”

The paper outlines the concept of “refugia,” which involves intentionally leaving a portion of the parasite population untreated. The idea is to maintain a population of drug-susceptible parasites to dilute the population of resistant ones. Refuges can include untreated animals, parasite eggs and larvae on pastures when animals are treated and life stages of the parasite not affected by treatment. The authors suggest, for example, that treating just half the herd at one time could reduce parasite loads while helping retain the population’s susceptibility to antiparasite drugs.

We posted a summary of the paper to our website,, and invited veterinarians and parasitologists to offer their thoughts on drug-resistant parasites and the FDA’s recommendations.

That request resulted in a detailed reply from a prominent veterinary parasitologist, which we also published, and that resulted in a thoughtful reply from FDA/CVM. You can read about FDA’s recommendations, and the resulting discussions, in “Dialog on drug-resistant parasites” on

Click here to register for the Oct. 14 webinar.