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Petition to Retain the Nobivac MyxO Vaccine U/D 21/2- Reply From MSD AH P78
- Thread starter Jack's-Jane
- Start date
Lillian
Warren Veteran
WHAT? They can't seriously be scrapping single vaccs? Oh god, I might not be able to vaccinate my buns anymore.
GrahamL
Wise Old Thumper
Hugo's There
Wise Old Thumper
There seems to be some confusion on whether the combined vaccine is the same as giving two separate doses at the same time or the equivalent of giving one dose :? I think this really needs to be clarified asap.
If it is like having 2 separate doses then that is bad news for special bunnies but if the effect on the immune system is the same as only having myxi alone then its really good news as it means compromised bunnies can be covered for both illnesses when they haven't been able to in the past :?
the more I hear about it the more confused I get, they really need to bring out a 'dummies' guide for the public before it is launched!
RedFraggle
Warren Veteran
From what I understand, it is a single antigen that will produce a response to immunise against both ilnesses. It is not a "combined vaccine" which would have two (or more) separate antigens provoking separate responses in the animal.
I still do not believe they will scrap the single vaccine, this would make no sense financially.
They never scrapped individual vaccines for measles mumps and rubella, the fact that the MMR was used came down to cost and convenience, the individual vaccines were always still available and some people chose to pay for separate vaccinations for their children.
I'm not a vaccines expert, but I do know the pharmaceutical industry, and I just don't think they would stop making the single vaccines.
I still do not believe they will scrap the single vaccine, this would make no sense financially.
They never scrapped individual vaccines for measles mumps and rubella, the fact that the MMR was used came down to cost and convenience, the individual vaccines were always still available and some people chose to pay for separate vaccinations for their children.
I'm not a vaccines expert, but I do know the pharmaceutical industry, and I just don't think they would stop making the single vaccines.
Jack's-Jane
Wise Old Thumper
Another bump !
Becky's Bunnies
Mama Doe
Have signed. x
Hugo's There
Wise Old Thumper
I get this bit, I think. But are all single responses the same or will the immune system need to produce a bigger single response to immunise against both illnesses than it would for one? I don't know if that is a silly question or not as I have very limited knowledge on the subject.
My personal feeling about continuing to produce the single vaccine is that it will become over priced due to a sharp fall in the number of people wanting it and they will then say there is no point producing it, especially as the RWAF have now said the double vaccine will now cost the same as a single vaccine. So if they do keep it going I think it will get to a point where no-one can afford to buy it especially if they have multiple rabbit. Apologies if I have posted this before, i have forgotten what i have posted where
rabbitapril
Mama Doe
:wave:
Lspacehopper
Wise Old Thumper
As the new vaccine is introduced, the old one will be withdrawn. We've been informed that it was part of the Licencing agreement that this would happen.
Pegasys
Alpha Buck
I think like most people I am still a little undecided about the new vaccine and whether it will be better than the single ones :? I do think I understand how it works though. My honours project was on rabbit vaccinations and I read quite a lot about the vaccines and a little on the research into creating a combined one. I don't want to patronise anyone but I can maybe help those who don't fully understand. It was almost two years ago that I did my study so I may not remember everything so if anyone who is more knowledgeable can correct or confirm this then please do
Viruses have proteins on the surface which are specific to each type and strain of virus. The proteins act as a kind of signal to the immune system which allows them to recognise a particular virus and produce antibodies which bind to them. The new vaccine uses just one strain of the myxoma virus. This specific strain has been engineered to have a gene that makes it produce one of the VHD virus proteins as well as producing its own proteins. What this means is that the immune system will only be reacting to a single virus, just as it does for the other single vaccines, but it will produce antibodies for a vhd protein as well as the myxoma ones and will create a ‘memory’ so that it will recognise any of these proteins in the future. Most viruses have several proteins on their surface so this is no different. If the bun is faced with either the myxoma or VHD virus once vaccinated, it will be able to recognise the proteins on the surface of both of them and can mount an immune response more quickly in order to prevent illness. This ‘memory’ of the proteins will only last a specific time which is why boosters are needed.
From what I can gather, and someone correct me if I am wrong, the reason there is a difference in reactions/tolerance of the single vaccines is because the myxo vaccine is a live attenuated vaccine and the VHD ones are inactive vaccines. Live virus vaccines trigger the immune system naturally, whereas inactive ones don’t. They need to add something called an adjuvant to inactivated vaccines. This is a chemical that triggers the immune response, the virus itself can’t do this because it is dead. The adjuvant has to produce a strong enough reaction to make the immune system respond to the dead virus in the same way as it would a live one, but I believe it is possible that this is what can also cause the adverse reactions that affect some rabbits. Because the new vaccine is live, it does not contain an adjuvant and so won’t necessarily cause the same problems as the single VHD vaccines. The combined one should work similarly to the old myxo vaccine, although it does depend on how the immune system responds to the new vaccine strain.
I don't think that this vaccine should be avoided just on the basis that a rabbit has reacted badly to a VHD vaccine in the past, but I still think we should wait and see how different rabbits cope with the new vaccine before we can make an informed decision. If some rabbits react to the new vaccine but have previously had the old myxo vaccine with no ill effects then that is a good basis for arguing against its withdrawal.
Viruses have proteins on the surface which are specific to each type and strain of virus. The proteins act as a kind of signal to the immune system which allows them to recognise a particular virus and produce antibodies which bind to them. The new vaccine uses just one strain of the myxoma virus. This specific strain has been engineered to have a gene that makes it produce one of the VHD virus proteins as well as producing its own proteins. What this means is that the immune system will only be reacting to a single virus, just as it does for the other single vaccines, but it will produce antibodies for a vhd protein as well as the myxoma ones and will create a ‘memory’ so that it will recognise any of these proteins in the future. Most viruses have several proteins on their surface so this is no different. If the bun is faced with either the myxoma or VHD virus once vaccinated, it will be able to recognise the proteins on the surface of both of them and can mount an immune response more quickly in order to prevent illness. This ‘memory’ of the proteins will only last a specific time which is why boosters are needed.
From what I can gather, and someone correct me if I am wrong, the reason there is a difference in reactions/tolerance of the single vaccines is because the myxo vaccine is a live attenuated vaccine and the VHD ones are inactive vaccines. Live virus vaccines trigger the immune system naturally, whereas inactive ones don’t. They need to add something called an adjuvant to inactivated vaccines. This is a chemical that triggers the immune response, the virus itself can’t do this because it is dead. The adjuvant has to produce a strong enough reaction to make the immune system respond to the dead virus in the same way as it would a live one, but I believe it is possible that this is what can also cause the adverse reactions that affect some rabbits. Because the new vaccine is live, it does not contain an adjuvant and so won’t necessarily cause the same problems as the single VHD vaccines. The combined one should work similarly to the old myxo vaccine, although it does depend on how the immune system responds to the new vaccine strain.
I don't think that this vaccine should be avoided just on the basis that a rabbit has reacted badly to a VHD vaccine in the past, but I still think we should wait and see how different rabbits cope with the new vaccine before we can make an informed decision. If some rabbits react to the new vaccine but have previously had the old myxo vaccine with no ill effects then that is a good basis for arguing against its withdrawal.
NLENG2000
Mama Doe
I think like most people I am still a little undecided about the new vaccine and whether it will be better than the single ones :? I do think I understand how it works though. My honours project was on rabbit vaccinations and I read quite a lot about the vaccines and a little on the research into creating a combined one. I don't want to patronise anyone but I can maybe help those who don't fully understand. It was almost two years ago that I did my study so I may not remember everything so if anyone who is more knowledgeable can correct or confirm this then please do
Viruses have proteins on the surface which are specific to each type and strain of virus. The proteins act as a kind of signal to the immune system which allows them to recognise a particular virus and produce antibodies which bind to them. The new vaccine uses just one strain of the myxoma virus. This specific strain has been engineered to have a gene that makes it produce one of the VHD virus proteins as well as producing its own proteins. What this means is that the immune system will only be reacting to a single virus, just as it does for the other single vaccines, but it will produce antibodies for a vhd protein as well as the myxoma ones and will create a ‘memory’ so that it will recognise any of these proteins in the future. Most viruses have several proteins on their surface so this is no different. If the bun is faced with either the myxoma or VHD virus once vaccinated, it will be able to recognise the proteins on the surface of both of them and can mount an immune response more quickly in order to prevent illness. This ‘memory’ of the proteins will only last a specific time which is why boosters are needed.
From what I can gather, and someone correct me if I am wrong, the reason there is a difference in reactions/tolerance of the single vaccines is because the myxo vaccine is a live attenuated vaccine and the VHD ones are inactive vaccines. Live virus vaccines trigger the immune system naturally, whereas inactive ones don’t. They need to add something called an adjuvant to inactivated vaccines. This is a chemical that triggers the immune response, the virus itself can’t do this because it is dead. The adjuvant has to produce a strong enough reaction to make the immune system respond to the dead virus in the same way as it would a live one, but I believe it is possible that this is what can also cause the adverse reactions that affect some rabbits. Because the new vaccine is live, it does not contain an adjuvant and so won’t necessarily cause the same problems as the single VHD vaccines. The combined one should work similarly to the old myxo vaccine, although it does depend on how the immune system responds to the new vaccine strain.
I don't think that this vaccine should be avoided just on the basis that a rabbit has reacted badly to a VHD vaccine in the past, but I still think we should wait and see how different rabbits cope with the new vaccine before we can make an informed decision. If some rabbits react to the new vaccine but have previously had the old myxo vaccine with no ill effects then that is a good basis for arguing against its withdrawal.
That's a really helpful explanation, thankyou! :thumb:
RedFraggle
Warren Veteran
That surprises me. I have never seen such a thing on a marketing authorisation, unless they have done this on ethical grounds.
It won't happen overnight though, and as Pegasys says, if there are adverse reactions, and these are appropriately reported their ongoing requirements to monitor the product in use could overturn that requirement.
LittleEskimo
Mama Doe
Will bunnies who have previously had the two separate vaccines be able to have this new combined vaccine? :?
RedFraggle
Warren Veteran
It says in the info from EMA
Special precautions for use in animals
Vaccinate only healthy rabbits.
Rabbits that have been vaccinated previously with another myxomatosis vaccine, or that have experienced natural myxomatosis infection in the field, may not develop a proper immune response against rabbit haemorrhagic disease following vaccination.
So until they demonstrate that previously vaccinated rabbits will be ok with it I cannot see how they would withdraw the separate vaccines. It also doesn't have anything in the conditions of the authorisation to state the other vaccine must be withdrawn.
All of the info is available here on the EMA website.
http://www.ema.europa.eu/ema/index....251.jsp&mid=WC0b01ac058001fa1c&jsenabled=true
and the quoted info is from the product info tab
Special precautions for use in animals
Vaccinate only healthy rabbits.
Rabbits that have been vaccinated previously with another myxomatosis vaccine, or that have experienced natural myxomatosis infection in the field, may not develop a proper immune response against rabbit haemorrhagic disease following vaccination.
So until they demonstrate that previously vaccinated rabbits will be ok with it I cannot see how they would withdraw the separate vaccines. It also doesn't have anything in the conditions of the authorisation to state the other vaccine must be withdrawn.
All of the info is available here on the EMA website.
http://www.ema.europa.eu/ema/index....251.jsp&mid=WC0b01ac058001fa1c&jsenabled=true
and the quoted info is from the product info tab
Santa
Wise Old Thumper
Many thanks, Pegasys, that's incredibly helpful and somewhat reassuring - I had the feeling that there needn't necessarily be a presumption that a bun previously unable to have a VHD vaccination would not be able to have this one, so that helps with our understanding of why that will (hopefully) prove to be the case.
But this was discussed at length in the other thread on the subject - someone's vet had asked the question and the response was that the testing had been done on rabbits vaccinated with the continental european myxo vaccine, which is actually made from the myxo virus, and that it shouldn't apply to the UK because the UK myxo vaccine isn't actually made from myxo. So there isn't the same risk that the existing antibodies will kill the vaccine off before the VHD immune response has been stimulated, because UK vaccinated bunnies don't have myxo antibodies, they have shope fibroma antibodies. It did seem, though, that the manufacturers are in the process of doing some additional testing on UK vaccinated bunnies to verify this...one of the reasons that many of us are still sitting on the fence until this is properly verified! I also read, but I can't remember where, it might have been the BVJ article, that the above also only applies if a bun has previously had the myxo vaccine but not a VHD vaccination. So even if a UK bun has previously been exposed to 'real' myxo, it should be ok if it has previously had a VHD vaccine. Of course I'd expect my vet to have these specific conversations and reassure themselves of this first!
But this was discussed at length in the other thread on the subject - someone's vet had asked the question and the response was that the testing had been done on rabbits vaccinated with the continental european myxo vaccine, which is actually made from the myxo virus, and that it shouldn't apply to the UK because the UK myxo vaccine isn't actually made from myxo. So there isn't the same risk that the existing antibodies will kill the vaccine off before the VHD immune response has been stimulated, because UK vaccinated bunnies don't have myxo antibodies, they have shope fibroma antibodies. It did seem, though, that the manufacturers are in the process of doing some additional testing on UK vaccinated bunnies to verify this...one of the reasons that many of us are still sitting on the fence until this is properly verified! I also read, but I can't remember where, it might have been the BVJ article, that the above also only applies if a bun has previously had the myxo vaccine but not a VHD vaccination. So even if a UK bun has previously been exposed to 'real' myxo, it should be ok if it has previously had a VHD vaccine. Of course I'd expect my vet to have these specific conversations and reassure themselves of this first!
Fantastic post, Pegasys. That is basically what I understood about the new jab, but not having studied this stuff formally at length and feeling really ill and knackered at the moment, I couldn't have explained it that way.
The new jab *could* be a good thing, in that it's only one immune response, as well as giving stronger protection against myxi. (I prefer to be optimistic about some things, plus am not responsible for any bunnies with complex health problems whom I'd be wary of getting a new vaccine for.) But really, it's an unknown quantity at the moment, and whether we're positive or wary it's all speculation.
The new jab *could* be a good thing, in that it's only one immune response, as well as giving stronger protection against myxi. (I prefer to be optimistic about some things, plus am not responsible for any bunnies with complex health problems whom I'd be wary of getting a new vaccine for.) But really, it's an unknown quantity at the moment, and whether we're positive or wary it's all speculation.
LittleEskimo
Mama Doe
I am planning on getting my buns first VHD done next week (already done myxi) so I will chat to my vet then about it all
Jack's-Jane
Wise Old Thumper
I am afraid I remain concerned, sorry
I cannot imagine risking giving my previous 'bad reaction to VHD Vaccine' Rabbits the new vaccine and just waiting to see if they are OK or not
I am not trying to be scare mongering or allowing my ignorance to blind me to new developments. As long as my Vet remains concerned I do too
Sorry
I cannot imagine risking giving my previous 'bad reaction to VHD Vaccine' Rabbits the new vaccine and just waiting to see if they are OK or not
I am not trying to be scare mongering or allowing my ignorance to blind me to new developments. As long as my Vet remains concerned I do too
Sorry
RedFraggle
Warren Veteran
I can completely understand your concerns. If I had any pet that reacted to vaccines I would be wary of any new vaccination. Alot of the time it is the adjuvant that causes the adverse reaction, so if that were the same in the new vaccine, then I think there'd be a higher chance of it happening again. If the adjuvent is different, then it could actually be better for them. My last cat was always poorly after vaccinations.
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