Using an IGR with a long-lasting residual is an excellent way to treat fleas, especially a product that tackles all flea life stages. 

With the warmer, more humid months of the flea season upon us, it’s worth a closer look at how pest managers can deliver high-performing flea treatments and avoid the dreaded callback.

For any flea treatment a thorough inspection is required and all affected indoor areas should be vacuumed and treated. Outdoor areas where the pets rest should also be treated. Whereas pest managers will always include an adulticide in their flea treatments, the use of an insect growth regulator (IGR) is often overlooked. However, the use of an IGR such as Sumilarv can deliver significant performance benefits.

Sumilarv contains the IGR pyriproxyfen, a juvenile hormone analogue. Although Sumilarv has been around for a while, we are still learning about its mode of action. Although its strong performance on fleas has always been known, only recently has it been demonstrated that pyriproxyfen kills flea larvae directly (Rust and Hemsarth, 2016).

The strong performance of Sumilarv can be attributed to the fact it impacts all flea life-stages:

  • Adults lay sterile eggs
  • Laid eggs fail to hatch
  • Larvae are killed directly
  • Pupal development is prevented
  • Some pupae will not hatch.

The two main reasons for flea treatment ‘failure’ are due to incomplete treatment or due to the hatching of pupa, which are notoriously difficult to control as they resist the penetration of insecticides. None of the insecticide treatments can penetrate the pupa, which is why if there are significant pupae present at the time of treatment, pest managers should factor in a return trip 1-2 weeks later, as customers may experience a ‘return’ of the problem. However, this should be momentary as the residual treatment should deal with any emerging adults.

Pyrethroid resistance in fleas is well documented. By using Sumilarv in conjunction with adulticides, it is also a great resistance management tool. In addition, although Sumilarv delivers excellent control of flea larvae on its own, in on-pet treatments, it has been shown to synergise the performance of other insecticides such as imidacloprid and fipronil.

However, there are two other key reasons why Sumilarv should be the go-to product for flea treatments – duration of performance and toxicological profile.

Pyriproxyfen is a very stable molecule and is active at very low doses. Trials on carpet in the laboratory have shown that it can still kill 90% of ea larvae a year after treatment (Figure 1).

Figure 1: Residual performance of Sumilarv on carpet

Sumilarv has an unscheduled poison classification due to its low mammalian toxicity – it specifically targets the juvenile insect life stages. Pest managers and customers should feel very comfortable with the use of Sumilarv on indoor surfaces. Additionally, pest managers could consider using Sumilarv as a standalone treatment for outdoor areas.

So for professional flea treatments and long-lasting protection inside and outside the home, Sumilarv should be in the mix.