FR2690838A1 - Vaccination ensemble against viral haemorrhagic disease of rabbits - comprises inactivated tissue culture of VHD with adjuvants injected intradermally without needles and can also incorporate vaccine against myxomatosis - Google Patents

Abstract

Ensemble for vaccination, by a parenteral route, against viral haemorrhagic disease in the rabbit, comprises an inactivated tissue culture of VHD virus with adjuvants and an appts. for intradermic admin. by jets. Individual vaccine doses are 0.2 ml contg. an associated food source. Pref. the appts. injects the dose in two successive vols. of 0.1ml by 3 jets at 90-110 bar. An effective dose is contained in 0.2ml. The adjuvant is aluminium hydroxide. The titre is SDV 90 in 0.2ml. At least one other viral or bacterial vaccine is incorporated, pref. myxomatosis, e.g. living Shope or a homologous vaccine, e.g. SG33. ADVANTAGE - VHD in rabbits has a high death rate. Vaccination using a needle requires frequent needle changes, is delicate and has a high labour cost. The claimed ensemble can be used on the inside of the outer ear of the rabbit; it is effective, economical and protection against other diseases (e.g. myxomatosis) may be incorporated.

Description

VACCINATION KIT FOR BLEEDING DISEASE
RABBIT VIRAL AND VACCINES PACKED FOR USE
IN THIS SET.

 The present invention relates to a vaccination package against rabbit viral hemorrhagic disease (VHD). It also relates to a vaccine against this disease, capable of being used in this set, as well as to a method of vaccinating rabbits against viral hemorrhagic disease.

 Rabbit viral hemorrhagic disease is a highly lethal disease caused by a small goblet virus known as VHD (Ohlinger & al., 1990). It causes 80 to 100 deaths in rabbit farms from 10 weeks.

 A number of vaccines have already been proposed which consist of tissue cultures of the virus suitably inactivated with formalin or 2-propiolactone and adjuvanted with aluminum hydroxide, saponin or an oily adjuvant. These vaccines are administered subcutaneously or intramuscularly by needle, which gives excellent protection but requires frequent needle changes to avoid the spread of other pathogens. Vaccination is delicate and costly in labor.

 In order to avoid these drawbacks, the applicant has already tried to carry out vaccinations using a conventional needle-less jet injection device, equipped with a head carrying an ejection nozzle, but these tests had failed due to the inability of the device to inject the required minimum dose of vaccine correctly and repeatedly.

 Consequently, the invention proposes to provide a set of vaccinations enabling vaccination against hemorrhagic rabbit viral disease, on an industrial scale, to be carried out efficiently and economically.

 Another objective of the invention is to carry out such vaccination with an extremely high probability of protection for each animal.

 The subject of the invention is a vaccination assembly allowing parenteral vaccination against rabbit viral hemorrhagic disease, based on tissue culture of the inactivated and adjuvanted virus, characterized in that it comprises an apparatus for administration by jet arranged for the intradermal distribution of individual doses with a volume of the order of 0.2 ml of vaccine, associated with a food source containing said vaccine conditioned to present a protective titer in said dose volume.

 The dose, of the order of 0.2 ml of vaccine, can be injected in one or more times and, for example, in two successive volumes of the order of 0.1 ml of vaccine.

 By jet administration apparatus is meant an apparatus allowing intradermal administration, without needle, by formation of a jet at high pressure. According to a particularly effective improved embodiment of the invention, an apparatus is used having a head with multiple nozzles, allowing the administration of the dose by several separate jets, the number of jets preferably being at least equal to three.

 The vaccination assembly according to the invention thus makes it possible to vaccinate a rabbit inside the ear's pavilion and this at an industrial rate.

The apparatuses for administering vaccines or other medicinal preparations by jet are in themselves well known and those skilled in the art can easily obtain and adapt them for the implementation as a whole according to the invention. A useful device is, for example, that sold by the company Béarn Mécanique
Aviation, Billères France under the Mésoflash brand or the Sanijet brand.

 The pressure of the jets is preferably of the order of 90 to 110 bar.

 By dose volume of the order of 0.2 ml is meant a volume which is preferably 0.2 ml but which can also be slightly different and, for example, be between 0.1 and 0.3 ml.

 The subject of the invention is also a vaccine against rabbit viral hemorrhagic disease based on an inactivated tissue culture of the VHD virus, designed for the implementation of the above-mentioned assembly and characterized in that it contains a protective title in a volume of the order of 0.2 ml (defined as above) and containing, preferably, an adjuvant with aluminum hydroxide. The vaccine is prepared so as to have a titer preferably of the order of SDV 90 in 0.2 ml.

 The subject of the invention is also a method of vaccination against the rabbit haemorrhagic viral disease, characterized in that an intradermal dose is administered in the rabbit ear pinna, of the order of 0, 2 ml per jet without needle, and in particular by plurality of jets, preferably three jets, of a vaccine based on tissue culture of VHD, preferably adjuvanted with aluminum hydroxide.

 The implementation of the invention may comprise, in addition to the inactivated valence of VHD, other viral or bacterial valences.

 Thus, the vaccine can in particular include the valence live myxomatosis. It is particularly remarkable to note that these two valences can be associated, the myxomatosis valence being dissolved in the liquid VHD valence.

 It is also remarkable to note that by the intradermal route protection against myxomatosis is also obtained.

 The myxomatosis valence can be, for example, made up of the living Shope valence (heterologous vaccine strain, Shope virus against myxomatosis) or else a valence from a homologous vaccine strain such as SG33.

 Other advantages and characteristics of the invention will appear on reading the following description, given by way of nonlimiting example and referring to the appended drawing in which the single figure represents a schematic view of an assembly according to the invention .

1 ") Preparation of VHD valence
The AGHD strain VHD virus was isolated in October 1988 from two tawny rabbits from Burgundy, suffering from viral hemorrhagic disease. The batch of viral primary semen is divided into ampoules and stored frozen at -70 "C.

Of course, other similar viral strains can be obtained without difficulty by sampling from sick rabbits.

 The virus is inoculated into susceptible rabbits subcutaneously or intramuscularly at the rate of 100 LD50.

After the manifestation of the specific symptomatology of the disease, the livers of infected rabbits are harvested, crushed and suspended in phosphate buffer supplemented with antibiotics. The ground material obtained is then clarified by centrifugation, then by sieving.

Inactivation is carried out by addition of formaldehyde.

The ground material, thus inactivated, forms the active principle and is mixed in a tank with aluminum hydroxide, in a physiological buffer containing sodium mercuriothiolate.

Composition of valence VllD
Each dose of VHD valence vaccine contains - inactivated VHD virus, strain AG88 qs to obtain
minimum 5 DV90 - Ai (as hydroxide) 0.35 mg t 0.7 mg - Sodium mercuriothiolate, maximum 0.02 mg - Free formaldehyde, maximum 0.075 mg - Kanamycin, maximum 0.30 mg - Vancomycin , at most 0.03 mg - Polymyxin, at most 0.06 mg - Physiological buffer, qs ............................ 0 , 2 ml
2) Preparation of valence Shope
The Shope fibroma strain underwent successive amplification passages on rabbit dermis, then adaptation passages on IDL7 cells (rabbit dermis cells). The batch of viral primary semen is distributed in ampoules then lyophilized and stored at low temperature below 40 C.

 The virus is multiplied on IDL7 cells (rabbit dermis cells). Harvesting takes place four days later.

 The valence is freeze-dried.

 Composition of Valencia Shope.

Each dose of Shope valence vaccine contains - Shope virus, titrating after reconstitution with
valence VHD, maximum 102'7 DICC50 - Sucrose, maximum 7.5 mg - Bovine albumin, maximum 1.0 mg - Kanamycin, maximum 0.05 mg - Polymyxin, maximum 0.015 mg 3) Preparation of valence myxomatosis SG33.

 The SG33 virus originates from a myxomatosis fibroid strain isolated from a rabbit suffering from myxomatosis. It underwent passages on rabbits then on embryonated eggs, on rabbit kidney cells at decreasing temperature up to 33 C and finally on chicken embryo cells. The strain was then further passaged on EOPS chicken embryo cells. The batch of viral primary semen is divided into ampoules1 then lyophilized and stored at -40 C.

 Composition of Valencia SG33.

Each dose of vaccine contains - SG33 virus, titrating after reconstitution with valence
VHD, minimum ................................. 102.0 DICC50 - Sucrose, maximum 8.2 mg - Bovine albumin, maximum .................... 1.1 mg - Kanamycin, maximum ............... ........... 0.055 mg - Vancomycin, maximum 5.5 pg
4) Assembly according to the invention
The assembly according to the invention comprises on the one hand a jet administration apparatus and on the other hand the vaccine supply source of the apparatus.

 The apparatus, of a completely conventional type, comprises a handle 1 above which is disposed a body 2 at the front end of which is located a chamber 3 with a volume of 0.2 ml. Via a filter 4, the chamber 3 continues with a plurality of extremely fine ejection nozzles 5 passing through the multi-injection head 6 of the device. The mechanism for ejecting the dose contained in the chamber by forming the high pressure jets, and which comprises a piston 8 penetrating into the chamber, can be of any type and multiple mechanisms have been described in the prior art .

 Mechanisms of this kind generally include a spring propelling the piston 7 forwards and a motor, electric, pneumatic or manual means, making it possible to return the piston back to a position where it is blocked so as to be released when it is pressed. on a trigger 8.

 The vaccine chamber of the apparatus is supplied with a multidose container 9, fixed to the upper part of the apparatus and connected by a suitable channel to chamber 3 so that, when of the movement of expulsion of the piston 7 towards the front, the communication with this source is closed while the contents of the chamber of 0.2 ml are expelled in the form of three jets, while on the contrary the reversal of the piston after the administration of the dose leads to the aspiration and filling of the chamber with the vaccine coming from the container 9. The jet pressure is of the order of 100 bar.

5) Implementation of the assembly according to the invention containing the single valence VHD
Two lots of sqnt rabbits made up - lot 1: 10 rabbits1 - lot 2: 3 rabbits.

 Each rabbit in the first batch receives a 0.2 ml dose intradermally in the pavilion of the ear thanks to two triggers of 0.1 ml at two injection sites, resulting in an intradermal distribution of the dose of 0, 2 ml at six injection points.

 Seven days after vaccination, the rabbits of lots 1 and 2 each receive 102 LD50 of the virulent test strain intramuscularly.

 Rabbits are observed daily. They are autopsied seven days after the test. The anatomo-pathological criteria retained are: hepatitis, hemorrhagic pneumonia, thymic hypertrophy. The test virus is tested for in livers by hemagglutination.

 The 10 rabbits in lot 1 remained in perfect health and showed no symptoms or lesion seven days after the test, while the three control rabbits in lot 2 died within three days of the test. The search for viruses in the 10 rabbits in lot 1 was negative.

6) Preparation and study of a bivalent vaccine
A volume of VHD valence dose prepared according to Example 1 is associated with a dose of Shope valence prepared according to Example 2. The association is carried out by taking up the Shope valence lyophilized in the VHD valence liquid medium. . The valence of Shope could be replaced by the valence SG33.

 Administration is carried out in exactly the same way as in Example 5.

Claims (9)

 1. Vaccination assembly allowing parenteral vaccination against rabbit viral hemorrhagic disease, based on tissue culture of the inactivated and adjuvanted VHD virus, characterized in that it comprises a jet administration device arranged for intradermal distribution individual doses with a volume of the order of 0.2 ml of vaccine, associated with a food source containing said vaccine conditioned to present a protective titre in said dose volume.  2. Assembly according to claim 1, characterized in that it is arranged to inject the dose in two stages by successive volumes of the order of 0.1 ml of vaccine.  3. Assembly according to one of claims 1 and 2, characterized in that the apparatus is arranged to distribute the vaccine in the form of at least three jets.  4. An assembly according to any one of claims 1 to 3, characterized in that the pressure of the jets is of the order of 90 to 110 bar.  5. Vaccine against the viral hemorrhagic disease of the rabbit intended to be used in the assembly according to any one of claims 1 to 4, based on an inactivated tissue culture of the VHD virus, characterized in that it has a protective title in a volume of the order of 0.2 ml.  6. Vaccine according to claim 5, characterized in that it has an adjuvant with aluminum hydroxide.  7. Vaccine according to one of claims 5 and 6, characterized in that the dose has a titer of the order of SDV 90 in a volume of 0.2 mi.  8. Vaccine according to any one of claims 5 to 7, characterized in that it comprises at least one other viral or bacterial valence.  9. Vaccine according to claim 8, characterized in that it comprises, in the liquid medium of the VHD valence, a myxomatosis valence, and in particular the valence of living -Shope or a homologous valence, such as Sis33.