Pest control: the keys to keeping fleas and ticks at bay

01 August 2014, at 1:00am

Tanya Leslie BVSC, MRCVS, technical manager at Merial Animal Health, answers questions about parasite control

What are the major types of flea and tick prevalent in the UK? 

Ctenocephalides felis, the cat flea, is the dominant species of flea in the UK and is most often the flea you see on pets coming into your practice. C. felis accounts for up to 99% of fleas found on cats and around 93% of those found on dogs.1 Pockets of C. canis do persist (Scotland and Northern Ireland) although it is rare.1 The cat flea has been also documented infesting horses, sheep and goats!

The most common species of tick in the UK is Ixodes ricinus, known to carry and transmit Lyme disease. Not present in the UK, but of great importance abroad is Rhipicephalus sanguineus, capable of transmitting a variety of diseases including Babesia canis3.

It can result in heavy infestations on inadequately treated dogs travelling in Europe. Dogs not treated with a tick-control product in a suitable time- frame before returning to the UK may bring this tick home with them.

What are the lesser known ones? 

Lesser known species of flea include Archaeopsylla erinacei (the hedgehog flea), Pulex irritans (the human flea), Spilopsyllus cuniculi (the rabbit flea) and Ceratophyllus (Nosophyllus) fasciatus (the rat flea). These species have been recovered from dogs and cats around the UK (the human flea has been found infesting dogs and cats in London).

The relatively rare tick species Dermacentor reticulatus survives in small pockets in the south-west. In Europe, this tick species is also capable of transmitting canine Babesia.

What is the most effective way of controlling them? 

Pets should be treated with flea control products throughout the year, not just summer. Most homes are centrally heated and the off-pet portion of the flea lifecycle is easily maintained in the home during winter.

A few months of central heating without flea control can result in an indoor infestation explosion the following spring, with no apparent warning. This is common and often affects pet owners who don’t normally see fleas (hence not treating over winter) leaving them disillusioned with their flea control and the advice given by the prescriber.

In the face of a heavy indoor infestation, treatment of all the pets in the home for 3-6 months and vacuuming more than usual may be required before the pre-existing pupae in the home are eradicated.

Tick control should be based on pet lifestyle and owner expectations. No product can completely repel ticks or prevent feeding and owners should be advised of this.

Repellent spot-ons can go some way to reducing the engorged tick burden but are often easily washed off when bathing or swimming. With any product, it is important to remember that efficacy decreases toward the end of the treatment period which can result in attachment of ticks for longer than expected.

This is especially important for dogs travelling abroad where the risk of tick-borne disease is high and growing puppies.

What advice should vets be giving clients? 

There are no products that stop fleas from jumping onto treated pets from the environment.

By using flea control regularly you certainly can keep the home free of infestation by killing fleas before they lay eggs and you can reduce the exposure of the treated pet to fleabites but owners should expect to see fleas for short periods at times when the pet is exposed to a high flea burden, especially in summer.

When it comes to ticks, the level of control required should be tailored to the individual. Products that allow the effective concentration in or on the pet to be replenished at monthly intervals are great for the high-risk periods and maintain a steady speed of tick kill from month to month.

How can practitioners improve compliance rates amongst clients? 

Owner compliance is the result of two factors: (a) How easy it is to treat the pet and (b) if they understand the importance of your recommendations.

Cats that are difficult to catch and dogs that shiver and shake at the thought of their flea control are much more likely to miss treatments. Whether a pet owner purchases a pack of 3, 6 or a single treatment, the importance of them coming back to the clinic for a refill regularly cannot be overstated.

It is your opportunity to review the protocol, remind them of the importance of regular treatment and to get an accurate weight. Palatable flea and tick control is an innovative way for owners to bond with their dogs and aids establishment of a regular parasite control routine.

When it comes to cats, only the brave tend to venture for tablets and so spot-on ea, tick and worm control remains the mainstay for cats.


  1. Bond, R. et al (2005) Survey of flea infestation in dogs and cats in the United Kingdom during 2005. Veterinary Record: April 2007.
  2. Yeruham, I. et al (1996) Ctenocephalides felis eainfestationinhorses.Veterinary Parasitology 62: 341-343. 
  3. Wall, R. (2012) A ticking clock for tick-borne disease? Veterinary Record: March 2012
  4. Dryden, M. (2013) Personal communication.