On the subject of when to vaccinate pregnant animals against Bluetongue - an email from Dr Ruth Watkins, virologist and farmer.
November 2 2008
In my opinion pregnant animals can be vaccinated at any stage of their pregnancy with inactivated BTV vaccines. The whole point of an inactivated vaccine is that this is safe to do unlike the live modified vaccines.
I looked to see if any other veterinary vaccines had saponin or quil A as adjuvants in them- this adjuvant is not yet used in human vaccines though it is being developed for use with more control in purity and composition than the current saponin and quil A which are derived from the bark of a tree (see Wikipedia under saponin). A vaccine called pregsure BVD for cattle has quil A and 3 other adjuvants in it and in the data sheet they advocate its use at any stage in the pregnancy and at any stage of getting pregnant or lactation.
Intervet are protecting themselves legally by saying that Bovilis 8 use around the time of conception or at the same time with any other vaccine is not advisable. Clearly in the short time from vaccine preparation to release they have not had time to check it out on pregnant animals. Also there has been no publication of the investigations done for complaints of abortion in the UK associated with the vaccine other than Chris Oura saying other unsuspected causes had been revealed in the complaints that have been investigated. Of course the biggest problem in this respect in Europe where BTV8 infection has occurred has been the virus infection itself.
I believe we should be using this inactivated vaccine in the normal way we would use other inactivated vaccines unless clinical complications are reported and verified that modify the conditions of its use. In human medicine a new inactivated vaccine is not first checked in combination with all other vaccines available on the market before allowing it to be used as part of a multiple vaccination schedule. Any medication in pregnancy is carefully considered but there is no reason to believe that inactivated vaccines are a risk if there is an indication for their use. Minor fever in response to a vaccine or intercurrent virus infection is not a risk to the pregnancy even an illness such as glandular fever does not have an adverse effect on the outcome of pregnancy.
We should be using these inactivated BTV vaccines sensibly- that is they can be given at the time of other vaccinations at a different site and by a different needle and syringe. Time must be given to respond to a vaccination before administering another, that is at least 2 weeks between doses of inactivated vaccine; in fact 3 or 4 weeks is the time advised for heptavac-P+ and covexin 8 and BTV8 intervet or BTV 8 Merial. BTV vaccination must be integrated into our vaccination regimes for our animals. It is a good thing if antibody level has been boosted by an annual vaccination one month before delivery so that there is a good level in the colostrum. I plan to do my ewes one month before they are due to start lambing with their annual vaccination for heptavac-P+ and BTV 8 using different needle and syringe and site (subcutaneously in the right and left shoulders). Farmers routinely give an annual vaccination at this time to boost the antibody with heptavac-P+ or covexin 8 etc. and this would be the natural time to give them their BTV 8 vaccination, which is likely to become a BTV 1, 6, and 8 vaccination. In the case of my cattle I will boost them whatever their stage of pregnancy before turnout in late spring because of the convenience of having them in the shed. I will give their booster at the same time as the covexin 8 booster.
I am not sure if there is any foundation in the prohibition of giving anti-fluke treatment at the same time as BTV 8 vaccination either. I cannot see this on any other data sheet. Any constraints put on the good practice of disease prevention such as fluke, pasteurella, clostridial toxin infections for no valid reason in order to prioritize BTV 8 vaccination should not be advocated. In the UK this year death from these diseases has hugely outweighed any BTV 8 infection. Clearly giving BTV vaccination throughout the summer has coincided little with these activities but in assuming inactivated BTV vaccination into normal animal husbandry health plans its common sense use and practicality of its use should be advocated.