Fipronil resistance or not?

Re: Fipronil resistance or not?

Martin Atkinson — Mon, 29 Jul 2013 18:43:53 GMT

[quote user="Thomas Johnson"]I agree, we do the work for the local Cats Protection branch, they often take in litters of kittens with fleas, the most cost effective way to treat them is Frontline Spray, and there are plenty of dead fleas in their bedding the next day.[/quote] Agreed but this is: A) because the exipient in the spray poisons them not the Fipronil - this is obvious as they start to die within a couple of minutes of application - you're effectively making them pissed! and, B) when you spray it is spread evenly all over and penetrates the coat, and doesn't rely on someone trying not very successfully to find a bald spot on the back of its neck!

Re: Fipronil resistance or not?

Thomas Johnson — Mon, 29 Jul 2013 15:14:26 GMT

[quote user="Neil Wheadon"]

No-one (I think) has mentioned the spray

A long forgotton product.

[/quote]

I agree, we do the work for the local Cats Protection branch, they often take in litters of kittens with fleas, the most cost effective way to treat them is Frontline Spray, and there are plenty of dead fleas in their bedding the next day.

Re: Fipronil resistance or not?

Rob Loxley — Sat, 27 Jul 2013 19:00:51 GMT

[quote user="Anthony Dennison"]That came in to effect in 2008. I was led to believe it was a little more recent than that.[/quote]

Indeed further searching comes up with http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2009/10/WC500004639.pdf which says the efficacy should be approximately 100%!

Anyhow, I'm still not convinced fipronil is any worse than it was, just there are better products appearing

Re: Fipronil resistance or not?

Anthony Dennison — Sat, 27 Jul 2013 11:39:41 GMT

[quote user="robloxley"]Dance, boy! EMEA guidelines for flea efficacy (http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2009/10/WC500004596.pdf) say minimum 95%[/quote]

That came in to effect in 2008. I was led to believe it was a little more recent than that.

Re: Fipronil resistance or not?

Rob Loxley — Fri, 26 Jul 2013 23:26:40 GMT

[quote user="Anthony Dennison"]

I got told by a rep (poss from Elanco? or maybe the people that make Activyl) that when Frontline was first licensed you only needed to prove 95% efficacy in killing fleas. Since then regulations have changed, so to be licensed you now need to prove a 98% efficacy.

Anyone else heard such a thing, or has a rep led me a merry dance?[/quote]

Dance, boy! EMEA guidelines for flea efficacy (http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2009/10/WC500004596.pdf) say minimum 95%

Re: Fipronil resistance or not?

Anthony Dennison — Mon, 22 Jul 2013 10:51:42 GMT

Anyone else heard such a thing, or has a rep led me a merry dance?

Re: Fipronil resistance or not?

Sarah Keir — Sat, 20 Jul 2013 14:01:56 GMT

[quote user="bob lehner"]

I asked the very question about Fipronil efficacy on this webinar. The very eminent speaker, Prof Michael Dryden (Mr Big in the world of fleas), said that whilst there was no scientific evidence of resistance to fipronil, Comfortis had performed rather better than fipronil in some studies - and reading between the lines he did not seem to defend fipronil's reputation very strongly.

[/quote]

Which drug company was paying him to do the webinar?

Re: Fipronil resistance or not?

Rob Loxley — Sat, 20 Jul 2013 10:13:03 GMT

[quote user="Utlendigur"]Imidocloprid is Advantage, I think (difficult to do in this heat!), but it and Advocate do have environmental action[/quote]

Have never been convinced by the real-world effectiveness of this; certainly if there's a household infestation then a big tin of insecticide spray would be my preference.

On a tangent - how are people finding owner compliance with comfortis in cats?

Re: Fipronil resistance or not?

Utlendigur — Fri, 19 Jul 2013 22:37:39 GMT

Imidocloprid is Advantage, I think (difficult to do in this heat!), but it and Advocate do have environmental action

Re: Fipronil resistance or not?

Francisco Gomez — Fri, 19 Jul 2013 22:30:45 GMT

[quote user="Nicola Lawlor"]

Changed her cats onto advocate and the problem was gone.

I basically do not sell any fipronil products these days as I think there are better products out there and easy to use.

[/quote] You probably right: Imidacloprid (Advocate) kills fleas and larvae. Fipronil doesn't (I think, please some1 correct me if I'm wrong) http://www.noahcompendium.co.uk/Bayer_plc/Advocate_Spot-on_Solution/-38253.html http://www.noahcompendium.co.uk/Merial_Animal_Health_Ltd/Frontline_Spot_On_Dog_10_ACU-_w_v_Spot_On_Solution/-31492.html

Re: Fipronil resistance or not?

Nicola Lawlor — Fri, 19 Jul 2013 22:17:09 GMT

From my point of view, I have had many clients in the last couple of years come in and tell me they have used frontline or one of the generic fipronil spot on treatment but still have a flea problem. I have had clients come in having used nothing and have a flea problem. I haven't had one client come in and tell me they are using any other POM-V flea product and still have a flea problem. If it was a compliance problem then surely there would be a proportion of clients using other products also having ongoing flea issues. A classic last year was a client who bought effipro from the clinic but had a flea problem so bought frontline from the pharmacy not realising it was the same product. She bought some household spray too but she still couldn't get on top of the flea problem. Changed her cats onto advocate and the problem was gone.

I basically do not sell any fipronil products these days as I think there are better products out there and easy to use.

Re: Fipronil resistance or not?

Francisco Gomez — Fri, 19 Jul 2013 22:12:55 GMT

I guess that if a cat goes out, it will bring fleas with them. In less than 24h (per datasheet) they will be able to lay eggs... I'm not defending or attacking the products, I just think that they're not perfect. They can't fight an infestation if the pressure is high enough. (Despite of O compliance)[quote user="Utlendigur"]

I agree with what you are saying with respect to beginning treatment of an infestation, but that doesn't explain the fairly large numbers of pets I, and other vets, have seen whose owners have conscientiously applied frontline as a preventative, as per data sheet, over the longterm (and often treated house - more than once) with no obvious reasons for treatment failing, and the pet still has developed a bad flea problem.

[/quote] I can't say that there isn't a resistance, I dont have proof to defend that or otherwise. But in my humble opinion, I don't think there is. Perhaps other products with a different mechanism of action work better than fipronil...

Re: Fipronil resistance or not?

Utlendigur — Fri, 19 Jul 2013 21:47:28 GMT

[quote user="Francisco Gomez"]

Therefore, even if a pet (and their home) is treated, it will continue to get fleas from pupa development. For months. The product will kill the flea, and another pupae will hatch and jump on.

--> Easiest thing for the owner to say: the product doesn't work..

--> Easiest thing for us vets to say: the product doesn't work.

[/quote]

Re: Fipronil resistance or not?

Utlendigur — Fri, 19 Jul 2013 21:40:27 GMT

[quote user="Juno Olsen"] it doesn't make a difference if it's NFA-VPS, all authorised products are automatically part of the pharmacovigilence scheme.[/quote]

I realise that, what I was trying to say is that the NFA-VPS category means clients are buying products from a variety of sources, and the practice has no record of what product that animal is on, whether it is the correct dose etc - compared to POM-V where the practice will either have sold the product or had made out a prescription. The responsibility for reporting is less clear (and many won't be reported because clients will be unaware of the scheme and will probably just try something else) and it is difficult for vets to report SARs when the client cannot even remember what the product was. I wonder out of interest how many SARSS forms are received from internet pharmacies or pet superstores.

Re: Fipronil resistance or not?

Neil Wheadon — Fri, 19 Jul 2013 21:36:55 GMT

No-one (I think) has mentioned the spray

A long forgotton product. The spot on was developed as a compromise as owners disliked spraying their cat/dog and I recall that monthly applications was the treatment of choice by dermatologists, many years ago (OK before resistance issues were even thought about)

In cats I use the 250ml product (2 squirts per kilo on a cat) and it's done pretty quickly, rubbing it in with a glove. I then sell the rest and tell the owners to initially do this monthly then extend to 2 monthly. As far as I'm aware none have come back, but then again I locum (but have just finished a 4 month long term job)

This has a better knock down effect and if vets are consistently seeing issues with this treatment, I'll start to be convinced.

Neil

Re: Fipronil resistance or not?

Francisco Gomez — Fri, 19 Jul 2013 18:33:09 GMT

Hmmm.... Can I handle the urge to post something?.. perhaps not...

Mi view on the thread:

Let's get to the basics. Virbac, Merial and all these guys only claim that their product kills fleas within 24 hours. Therefore you can see a flea in a cat or dog, but if this animal is being treated, the flea will die in about 24 hours.

http://www.virbac.co.uk/files/resources/effipro_spot-on_datasheet.pdf

A phase of the the flea cycle: the pupae, is resistant to insecticides.

Virbac Indorex, for instance, says that it 'kills' fleas at your home and 'prevents' larvae development. It does nothing against pupa.

http://www.virbac.co.uk/product.aspx?pid=160&product=52&&category=62#page=page-BRAND

....

Therefore, even if a pet (and their home) is treated, it will continue to get fleas from pupa development. For months. The product will kill the flea, and another pupae will hatch and jump on.

--> Easiest thing for the owner to say: the product doesn't work..

--> Easiest thing for us vets to say: the product doesn't work.

One of my vet friends from Spain is a Merial rep. Frontline is sold in hot Spain 'A LOT'. If a manufacturer created a product that gets rid of flea infestation in a couple of months, kills all of the flea stages and has a 100% prevention, they could afford to sell the product for 3 or 4 times the price of frontline or effipro. And to provide with papers to support it.

...

Therefore I don't think these products don't work. I just think that we are expecting them to do what they don't.

Re: Fipronil resistance or not?

Mark Hedberg — Fri, 19 Jul 2013 16:38:26 GMT

[quote user="robloxley"]

[quote user="Mark Hedberg"]The problem is, while I think fipronil has some issues in the UK, proving an actual resistance to research paper standard is difficult.[/quote]

Mr Google says frontline sales were worth £24 million /yr in the UK alone - pretty high incentive for any competitor to do the work?

[/quote]

You'd think so, wouldn't you? I don't know why nobody's done the work. Perhaps nobody wants to spark off a Spot On War or something. (I like imidoclop and spinosad better than fipronil.)

Re: Fipronil resistance or not?

Juno Olsen — Fri, 19 Jul 2013 15:23:54 GMT

Appreciate that it takes time to do, but owners can report these themselves online if you direct them to the website. I do it quite frequently, and many owners like that as it feels like their concerns are being taken seriously. You can still report it if you don't have the batch number and it doesn't make a difference if it's NFA-VPS, all authorised products are automatically part of the pharmacovigilence scheme.

Re: Fipronil resistance or not?

Utlendigur — Fri, 19 Jul 2013 14:40:21 GMT

[quote user="Juno Olsen"]

Can I suggest that anyone experiencing lack of efficacy to fipronil submits a yellow form if you're not doing it already, or gets the owner to do it online if time is an issue. While there is no scientific evidence of resistance, if the VMD start getting lots of reports of suspected lack of efficacy, then it may be looked at more closely. Especially now as there are more and more fipronil generics out there.

[/quote]

Problem with this is it takes time to do, and if you are seeing several a day, that mounts up. Plus owners have usually bought it from elsewhere, so not batch numbers or other details, and they are usually vague as to what exact product it is "I put some spot-on on him" ...."OK but which one?"......."You know, Spot-On" (complete with mime of applying it). In fact the move to NFA-VPS seems to be a good way for frontline et al to escape from scrutiny under SARSS

Re: Fipronil resistance or not?

Utlendigur — Fri, 19 Jul 2013 14:34:00 GMT

[quote user="Joyce Whitehead"]We now use Comfortis or Activyl, or in tick prone animals Seresto collars, all of which seem to work well.[/quote]

Activyl have now brought out Activyl Plus which covers ticks aswell (in dogs). I'll second Seresto collars - use them on my own dogs as we're in a tick area. I haven't seen a single tick on them this year but was getting loads last year with frontline (and I'm useless at remembering to apply spot-ons regularly).

Re: Fipronil resistance or not?

Rob Loxley — Fri, 19 Jul 2013 13:40:42 GMT

[quote user="bob lehner"]The very eminent speaker, Prof Michael Dryden (Mr Big in the world of fleas), said that whilst there was no scientific evidence of resistance to fipronil, Comfortis had performed rather better than fipronil in some studies - and reading between the lines he did not seem to defend fipronil's reputation very strongly[/quote]

Because he's now being paid by Eli rather than Merial?!!

Re: Fipronil resistance or not?

Rob Loxley — Fri, 19 Jul 2013 13:40:38 GMT

[quote user="Mark Hedberg"]The problem is, while I think fipronil has some issues in the UK, proving an actual resistance to research paper standard is difficult.[/quote]

Mr Google says frontline sales were worth £24 million /yr in the UK alone - pretty high incentive for any competitor to do the work?

Re: Fipronil resistance or not?

Miriam Lodewyks — Fri, 19 Jul 2013 12:36:11 GMT

Our main flea prophylaxis is Frontline Combo, but we do stock Advocate.

The clue is in the word PROPHYLAXIS. I find that if used correctly and preventatively Frontline works just fine. Infestations are usually caused by incorrect use (where did this "lasts for 3 months" idea originate???), and are admittedly hard work to eliminate. Often I just switch to Advocate, and ALWAYS advise environmental control.

Re: Fipronil resistance or not?

Bob Russell — Fri, 19 Jul 2013 11:52:52 GMT

Changing from Fipronil to Promeris (for example) generally sorts the problem out and even a year later (when compliance has returned to its previous low!) fleas are noted for their absence.

Is it resistance? Difficult to prove as this is a very specific process. Do fipronil products work or offer good value? Not even at half price IMO!

Re: Fipronil resistance or not?

Mark Hedberg — Fri, 19 Jul 2013 11:05:20 GMT

The problem is, while I think fipronil has some issues in the UK, proving an actual resistance to research paper standard is difficult. After all - which species of flea? what is the mechanism of resistance? Proving lack of efficacy is a little easier but still challenging, as getting pet owners to perform to the same exacting standard is difficult. So I think some of it is down to owner compliance, but then again, changing to a different active ingredient anecdotally has made a difference in some cases.