Yes, it would be useful to have information from Intervet detailing the level of abortions reported post-vaccination as all adverse affects reports should be going to them as well as VMD.

Yes, there certainly have been some reports of abortions but these have been relatively few as far as I am aware. There is a short-lived spike in temperature post-vaccination which may in very few cases result in abortion - abortion may also be related to the stress induced by the vaccination process. There is no reason why inactivated vaccines should result in abortions and they also should not affect the fertility of either ewes or tups. Any small spikes in temperature resulting from vaccination may temporarily affect the sperm count in tups but this would be short-lived. It is clear from what we have seen in Northern Europe in 2007 that the damage that would occur to the herd/flock if infected with BTV would far outweigh the minor adverse affects that may result from vaccination.

 

Still no new cases of BTV in the UK in 2008, however this is not unexpected as in 2007 there were no outbreaks in Northern Europe until early July in Germany and late July in France. Hopefully the high levels of vaccine coverage in the 2007 infected areas in the UK will significantly delay and then slow down the spread of BTV-8 this summer. Only time will tell. 

The problem will be if we get a limited number of outbreaks in 2008 as this will make it very difficult to try to persuade farmers to continue vaccinating into 2009. It is vital that we maintain the vaccination momentum into the future in order to eradicate this serotype from the UK.

 

Chris

Thank you Jane.

 

I know the rumours continue, and suspect many reasons behind them, but they are rumours rather than anything else.

 

There is general good advice about the use of any vaccines, and that is don't use within 2 weeks either side of insemination or two weeks before lambing/calving.  This is because the stress of handling can lead to issues.  However there is no indication that there should be extra warnings regarding Bovilis® BTV8 and, in fact, I remain surprised at the low number of reports that we have received, ie: ones we can investigate.

 

The number of abortions reported as associated with vaccination remain low, running at not much more than one report for every million doses used.  It is important to note that people will report things that happen even as much as eight weeks after vaccination and still be associating it with the vaccination.  Obviously there are a number of reasons why abortions occur and there is a "normal" background level of abortion.  However, we investigate every report we receive and, while we are still waiting on further information on some, those that have been concluded have shown Neospora infection in four cases and a bacterial infection in another, none of which are anything to do with the vaccine.

 

As to the reports of infertility, how could these be based on fact?  People can't be finding that vaccination makes rams infertile or stopping ewes getting in lamb when no rams will have been tupping yet.  We have not received any reports that I am aware of, of infertility post vaccination in cattle or sheep.

 

Most of these rumours are driven by confusion. Certainly the disease itself can cause abortion and cause infertility.  And it seems likely that LIVE vaccines can have these effects as well.  However, as both you and Chris have pointed out, this is a killed vaccine.

 

The basic science is that a killed vaccine cannot cause disease as there is no virus to replicate.  Therefore it cannot cause the signs associated with the disease.  

The adjuvants in use in this vaccine are also used in other vaccines for pregnant and lactating animals and they do not cause infertility or abortion.  Finally the short lived temperature spike that occurs after the us of any vaccine is not of a scale to be a usual problem.

 

The number and type of reports of suspected side effects for Bovilis® BTV8 are at about the same level as those to older and well established vaccines.  We continue to investigate reports of suspected adverse events for all our products but it is unusual for these to be directly related to the product.

 

I hope that this is of help.