Top 5 Takeaways from a Zoomies 2026 lecture With Professor Jane Sykes

Introduction

The use of parasiticides in companion animal medicine is at a pivotal moment – much like antimicrobial resistance was decades ago. With the animal health parasiticide market projected to reach $14.1 billion in 2027, these products have widespread use in veterinary practice. However, emerging resistance, growing environmental concerns, and the availability of increasingly broad-spectrum combination products demand that we move beyond “blanket therapy” toward more strategic, risk-based approaches to parasite prevention.

Here are our top 5 takeaways from this excellent lecture:

1. Resistance Is Emerging Across Multiple Parasite Species and Drug Classes

While most parasiticide failures still result from re-exposure, larval leak, or poor compliance, definitive resistance has been documented in:

• Heartworms (Dirofilaria immitis) to macrocyclic lactones (confirmed via SNP assays in p-glycoprotein transporters)
• Hookworms (Ancylostoma caninum) to benzimidazoles (widespread across the US)
• Fleas and brown dog ticks to pyrethroids (via voltage-gated sodium channel mutations)
• Dipylidium caninum to praziquantel

Importantly, however, resistance should not be assumed until other causes of treatment failure are ruled out.

2. Environmental Impacts Are a Growing Concern That Must Be Considered

Different parasiticides have vastly different environmental persistence profiles:

Companion animal use contributes measurably to water contamination, even in regions where agricultural use has been restricted.

3. The Shift from Combination Products to Targeted Therapy Is Critical

Combination products, while convenient, complicate resistance management:

• A parasite may be resistant to one component but not another
• Using combination products unnecessarily may select for resistance to drugs the animal doesn’t actually need
• Individual products (rather than fixed combinations) would allow more tailored prescribing

Risk-based prescribing is crucial, and should be based on:

• Geographic region and locally circulating pathogens
• Individual animal’s lifestyle (indoor vs. outdoor, travel history)
• Specific parasites of concern (e.g., Ehrlichia canis requires tick repellence due to 2-hour transmission time)

4. Non-Chemical Prevention Methods Deserve Renewed Attention

Before modern parasiticides, veterinarians relied heavily on environmental control. These strategies should be re-emphasized:

• Thorough vacuuming of homes for flea control
• Removal of standing water to reduce mosquito breeding
• Brush removal around homes to discourage ticks
• Habitat reduction and limiting wildlife access
• Inspection and removal (though impractical for many owners)

Future alternatives like anti-tick vaccines remain an area of research but have not yet reached clinical availability.

5. Parasiticide Stewardship Programs Are the Future

Just as antimicrobial stewardship transformed antibacterial prescribing, parasiticide stewardship requires:

• Client education on proper use, disposal, and non-chemical alternatives
• Tailored (not blanket) prescribing based on individual risk assessment
• Testing to assess risk rather than presumptive treatment
• Recording and monitoring use to track efficacy and emerging resistance
• Industry responsibility to make individual (non-combination) products available

The BVA, BSAVA, and ESCCAP have already developed risk-based guidelines, while CAPC (US) still recommends year-round blanket treatment—a gap the speaker is actively working to address through ISCAID and WSAVA initiatives.

Bottom Line: 

We must move from “magic gun” broad-spectrum prevention toward parasiticide stewardship, using the right drug, for the right parasite, in the right patient, at the right time, while considering both resistance risk and environmental impact.