Target Species
Sheep (ewes).
Indications for use
For the active immunisation of susceptible breeding female sheep to reduce the effects of infection by Toxoplasma gondii, namely early embryonic death, barrenness and abortion.
Vaccination with Toxovax is known to protect for at least two lambing seasons.
Contraindications
Do not vaccinate animals less than 3 weeks before mating.
Do not use during pregnancy.
Special warnings for each target species
Toxoplasma is only one of the causes of abortion in sheep.
Where abortion occurs in sheep which have been vaccinated with Toxovax then it is recommended that veterinary advice is sought immediately to clarify the likely cause.
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.
Only healthy animals should be vaccinated.
Special precautions for use
In target species: None.
Operator warnings
Special precautions to be taken by the person administering the product to animals:
Toxovax should not be handled by pregnant women, or women of child bearing age as the vaccine may interfere with normal foetal development.
Toxovax should not be handled by persons who are immuno-deficient (e.g. AIDS sufferers; persons undergoing chemotherapy or taking immuno-suppressive drugs).
Operators should wear gloves when handling the vaccine.
Living tachyzoites can cause disease in man.
Care should be taken to avoid self-injection and to avoid vaccine getting into the mouth or the eyes.
In the case of self-injection, immediate medical advice should be sought and the doctor should be informed that self-injection with a living tachyzoite toxoplasma vaccine has occurred.
Pyrimethamine therapy is the current recognised treatment for toxoplasmosis in humans
Adverse reactions
A transient temperature rise is normally observed (up to 41°C returning to normal within 7-8 days of vaccination).
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 Enzovax.
No information is available on the safety and efficacy of this vaccine when used with any other veterinary medicinal product except Enzovax.
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
The vaccine is supplied as a liquid concentrate containing 20 or 50 doses.Immediately before use this is added to the 40 or 100ml (respectively) diluent (Unisolve), giving a dose volume of 2ml.
Injection equipment:
To minimise the risk of self-injection the vaccine should be administered using disposable automatic syringes fitted with a guarded needle system according to the manufacturer's instructions.
An administration kit including a vented transfer devise for vaccine reconstitution and disposable automatic syringe with a guarded needle system is available from the company.
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.
Dilution:
Protective gloves (impervious rubber or plastic such as disposable medical gloves or surgical gloves (EU standards) and goggles or a face visor should be worn when diluting the vaccine.
If using the vented transfer device push one end of the device through the centre of the Unisolve vial using a firm, twisting action. Similarly, push the vaccine vial onto the opposite end of the device taking care to ensure the spike penetrates the centre of the vial bung. The vaccine concentrate will drain into the diluent vial. Remove the empty vaccine vial and transfer spike from the diluent vial and place into an appropriate disinfectant solution.
Alternatively, withdraw the entire contents of the vaccine concentrate vial using a sterile disposable 10ml syringe and either a 16G or 18G sterile needle. Carefully expel any air from the syringe and inject the contents into the diluent vial.
With the diluent vial upright withdraw 5-10ml of air prior to removing the needle. This maintains the vial under negative pressure and avoids spillage when the needle is removed.
After dilution the vaccine should be kept cool and away from light and used as soon as possible (within 2 hours).
Ideally only dilute one vaccine vial at a time.
Administration
Dose: 2ml by intramuscular injection.
Basic vaccination
Animals should be given a single dose at least 3 weeks prior to mating. 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.
Re-vaccination
After 2 years, a single dose at least 3 weeks prior to mating.
Overdose
No particular signs at 20 times dose other than a transient temperature increase as seen with a single dose but up to 41.5 - 42°C.
Withdrawal Period
Meat and offal: 42 days