killickchick, that is awful, to hear your dog died so quickly and unexpectedly :(
Can I ask roughly whereabouts in the UK you're based?
And also, was the worm which killed your dog the angio[etc] one, or was it one of the other 3 types of lungworm - or don't you know?
>I an constantly on tenterhooks with my girl as Panacur only treats, not prevents.
The way the preventatives work is by killing the immature forms of the worm, before they've developed into the adult. To 'treat' lungworm would involve to kill the adults as well as the immature forms. So if something 'treats', it is doing more than something which just 'prevents'.
However, the situation in the UK is actually very complicated. The link someone posted (it wasn't me) was v helpful. To recap:
We're talking about 4 different worms and the various meds we're discussing (Panacur, Milbemax and Advocate) don't even claim that they work against all the worms. Some vets seem to think they do, but I don't know if that is based on any research or experience or is just misinformation as a result of being unaware that there are 4 kinds of worm.
They are:
Angiostrongylus vasorum (this is the one most of you mean when you say 'lungworm', it is the one which has allegedly increased in prevalence recently)
Oslerus osleri
Filaroides hirthi
Crenosoma vulpis
Panacur:
" for the treatment of dogs infected with lungworm Oslerus (Filaroides) osleri "
Milbemax:
" Angiostrongylus vasorum (reduction of the level of infection; see specific treatment schedule under dosage and administration)."
" Crenosoma vulpis(reduction of the level of infection),"
Advocate:
" prevention of heartworm disease (L3 and L4 larvae of Dirofilaria immitis) and angiostrongylosis (L4 larvae and immature adults of Angiostrongylus vasorum), treatment of Angiostrongylus vasorum and Crenosoma vulpis"
These are the specific uses which the meds have been tested against and found to be effective. They may or may not also have other functions and be effective against other of the 4 lungworms, we don't know. As you'll see, there is no one drug which treats all 4 types of lungworm. Several only 'reduce the level of infection' rather than treat. And there are specific treatment schedules to follow, if you want to use these meds for lungworm:
Panacur:
" For the control of lungworm Oslerus (Filaroides) osleri in dogs administer 1 ml per 2 kg bodyweight daily for 7 consecutive days (= 50 mg fenbendazole/kg bodyweight daily for 7 days)." [Not sure what 'control' means, in our attempt to understand the difference between 'treat' and 'prevent'.]
Milbemax:
"For Angiostrongylus vasorum infection, milbemycin oxime should be given four times at weekly intervals. It is recommended, where concomitant treatment against cestodes is indicated, to treat once with MILBEMAX and continue with the monovalent product containing milbemycin oxime alone, for the remaining three weekly treatments." [This means that you should give Milbemax one week, then for the next 3 weeks you should give a product which contains one of the 2 drugs in Milbemax - milbemycin oxime. Unfortunately we don't have such a drug in the UK. They do in the US, it's called Interceptor. Quite why someone can't sell Interceptor over here, I don't know.]
Advocate:
"Treatment and Prevention of Angiostrongylus vasorum (Dogs)
A single dose should be administered. A further veterinary examination 30 days after treatment is recommended as some animals may require a second treatment.
In endemic areas regular four weekly application will prevent angiostrongylosis and patent infection with Angiostrongylus vasorum.
Treatment of Crenosoma vulpis (Dogs)
A single dose should be administered."
So there you have it.
killickchick, the reason I asked if it was angiostrongylus which your dog died of, is because, if you missed only 1 dose of Advocate, I can't see how it could have been: The lifecycle of the worm is such that it would take longer than that for them to develop through the various larval stages and then reach such a severe worm burden as you describe. There is more info on the lifecyle of it here:
http://journals2005.pasteur.ac.ir/TP/21(2).pdf (V good article - include the .pdf to make the link work - copy and paste what I wrote and don't just click on it!) I do wonder if it was instead one of the other lungworms which Advocate doesn't cover - Oslerus osleri or Filaroides hirthi . That would explain how you could be treating with Advocate and still end up with lungworm.
Finally in terms of whether the worms can be found in stool samples or not - often they are not found (this taken from article above): "Larval recovery from the faeces of infected animals is unreliable because of poor test sensitivity, as well as a relatively long pre-patent period and possibly intermittent egg production by adult worms." So I for sure would not be doing stool samples before deciding whether or not to treat.
The other point which comes across in the article is just that no one knows much about lungworm. We don't even know if it can be transmitted direct from fox faeces to dogs (if a dog eats faeces), or if it needs an intermediate host by way of a slug or snail. There are not enough answers about it, and the patchy info and guidelines from drug companies about how to prevent it echo this confusion...