Target species
Sheep (ewes).
Indications for use
For the active immunisation of susceptible female breeding sheep to reduce abortion caused by Chlamydia abortus infection.
Onset of immunity: Vaccination should be conducted at least 4 weeks before mating.
Duration of immunity: Challenge studies have demonstrated that protection against enzootic abortion and excretion of Chlamydia abortus post-challenge is undiminished for at least three years post vaccination with the veterinary medicinal product. Field studies in endemically infected flocks maintaining a policy of vaccinating incoming ewes with the vaccine indicate that enzootic abortion levels remain very low in ewes vaccinated 4 years previously.
Contraindications
Do not vaccinate pregnant animals.
Do not vaccinate animals less than 4 weeks before mating.
Do not vaccinate animals which are being treated with antibiotics, particularly tetracyclines.
Special warnings for each target species
Vaccinate healthy animals only.
Chlamydia abortus is only one of the causes of abortion in sheep. If the abortion rate remains unchanged in flocks which have been vaccinated with the vaccine it is recommended that veterinary advice is sought.
The epidemiology of abortion due to Chlamydia abortus in ewes involves a long incubation period. Ewes that abort in any lambing season have usually been infected at the previous lambing. Field trial data indicate that vaccinating incubating ewes will reduce the incidence of abortion, but a proportion can still go on to abort.
Care should be taken in handling such abortions as susceptible humans may be at risk of infection.
A good immune response is reliant on the reaction of an immunogenic agent and a fully competent immune system. Immunogenicity of the vaccine antigen will be reduced by poor storage or inappropriate administration. Immunocompetence of the animal may be compromised by a variety of factors including poor health, nutritional status, genetic factors, concurrent drug therapy and stress.
Special precautions for use
None.
Operator warnings
Care should be taken to avoid accidental self-injection. In case of accidental self-injection, seek medical advice immediately and show the package leaflet or the label to the physician. The physician should be informed that self-injection with a living chlamydia vaccine has occurred. Tetracycline therapy is the current recognised treatment for infection with Chlamydia abortus in humans. Personal protective
equipment consisting of gloves should be worn when handling the veterinary medicinal product.
The veterinary medicinal product should not be handled by pregnant women or women of childbearing age as the vaccine may cause abortion.
Immunocompromised persons are advised to avoid contact with the vaccine.
Adverse reactions
Sheep (ewes):
Very common (>1 animal / 10 animals treated): | Elevated temperature1. |
Very rare (<1 animal / 10 000 animals treated, including isolated reports): | Abortion2; Hypersensitivity reaction (e.g. Tachypnoea, pale mucous membranes, collapse)3. |
1 Transient and average up to 1.5 °C for a maximum of 3 days after vaccination.
2 May occur where the vaccine strain can be identified.
3 Such reactions may evolve to a more severe condition (anaphylaxis), which may be life-threatening.
Reporting adverse events is important. It allows continuous safety monitoring of a veterinary medicinal product. Reports should be sent, preferably via a veterinarian, to either the marketing authorisation holder or its local representative or the national competent authority via the national reporting system. See the package leaflet for respective contact details.
Use during pregnancy or lactation
Do not use during pregnancy.
Interactions
Safety and efficacy data are available which demonstrate that this vaccine can be administered on the same day but not mixed with Toxovax. The vaccines should be given at different sites.
No information is available on the safety and efficacy of this vaccine when used with any other veterinary medicinal product except the product mentioned above. A decision to use this vaccine before or after any other veterinary medicinal product therefore needs to be made on a case-by-case basis.
Amounts to be administered and administration route
Intramuscular use or subcutaneous use.
Dose: 2 ml.
Reconstitution:
The vaccine is reconstituted with the solvent (Unisolve) immediately prior to use, allowing 2 ml of solvent per dose.
If using the vented transfer device push one end of the device through the centre of the vaccine vial using a firm, twisting action. Similarly, push the Unisolve vial onto the opposite end of the device taking care to ensure the spike penetrates the centre of the vial bung. Carefully allow solvent to flow into the vaccine vial without completely filling it. Ensure the vaccine plug is fully dissolved and then invert until all the vaccine suspension drains into the solvent vial. Remove the empty vaccine vial and the transfer spike from the solvent vial and place them into an appropriate disinfectant solution.
Alternatively, remove approximately 5 ml of Unisolve from the vial with a syringe and needle, inject into the vaccine vial and swirl gently until the vaccine plug is fully dissolved. Remove the vaccine suspension from the vial, re-inject into the solvent vial and mix gently. Great care should be taken not to generate an aerosol. After reconstitution the vaccine should be kept cool and used as soon as possible (within 2 hours).
Visual appearance after reconstitution: Off-white suspension.
Administration
Ewe lambs, where it is intended to breed from them, may be vaccinated from 5 months of age. Shearlings and older ewes should be vaccinated during the 4 month period prior to mating.
Vaccination must take place at least 4 weeks before mating.
Injection equipment
To minimise the risk of self-injection the vaccine should be administered using a disposable automatic syringe fitted with a guarded needle system according to the manufacturer's instructions. It is vital that a vented draw off tube is used with this equipment.
Regular checks should be made to ensure the syringes are properly calibrated. Carefully attach the vial of reconstituted vaccine to the injection equipment and avoid creating aerosols during the priming process. It may be advisable to wear a visor while carrying out this operation.
Revaccination policy
Challenge studies have demonstrated that protection against enzootic abortion and excretion of Chlamydia abortus post-challenge is undiminished for at least three years post vaccination with the veterinary medicinal product.
Revaccination is recommended every 3-4 years depending on farm management practices and conditions.
Field studies in endemically infected flocks maintaining a policy of vaccinating incoming ewes with the vaccine indicate that enzootic abortion levels remain very low in ewes vaccinated 4 years previously.
Overdose
No particular clinical signs at ten times the dose other than a transient pyrexic response similar to that seen after a single dose but up to 2 °C.
Withdrawal periods
Meat and offal: 7 days.