Vaccine for intradermal application against PCV2 and PRRS virus infection

Abstract

The present invention pertains to a vaccine comprising in combination non-replicating immunogen of porcine circo virus type 2 and live attenuated PRRS virus for use in prophylactically treating an animal against an infection with porcine circovirus type 2 (PCV2) and an infection with PRRS virus by administration of the vaccine into the dermis of the animal.

Claims

1. A single-dose vaccine comprising in combination a non-replicating immunogen of porcine circovirus type 2 (PCV2) and a live attenuated porcine reproductive and respiratory syndrome (PRRS) virus, wherein the vaccine is administered intradermally for use in prophylactically treating an animal against an infection of PCV2, PRRS virus, or both PCV2 and PRRS virus.

2. The vaccine of claim 1, wherein the vaccine is administered with a needle-less vaccination device.

3. The vaccine of claim 1, wherein the non-replicating immunogen of PCV2 is recombinantly expressed ORF2 protein of PCV2.

4. The vaccine of claim 1, wherein the non-replicating immunogen of PCV2 is baculovirus expressed ORF2 protein of PCV2.

5. The vaccine of claim 1, wherein the vaccine additionally comprises a non-replicating immunogen of Mycoplasma hyopneumoniae.

6. A method for prophylactically treating an animal against an infection with porcine circovirus type 2 (PCV2), an infection with porcine reproductive and respiratory syndrome (PRRS) virus, or an infection with both PCV2 and PRRS virus, by administrating into the dermis of the animal a vaccine comprising in combination a non-replicating immunogen of PCV2 and a live attenuated PRRS virus.

7. The method of claim 6, wherein the immunogen of PCV2 and the live attenuated PRRS virus are combined in the vaccine within 24 hours before administration.

8. The method of claim 6, wherein the immunogen of PCV2 and the live attenuated PRRS virus are combined in the vaccine within 6 hours before administration.

9. A method of manufacturing a vaccine comprising combining a non-replicating immunogen of porcine circovirus type 2 (PCV2) and live attenuated porcine reproductive and respiratory syndrome (PRRS) virus into one single-dose vaccine for intradermal administration to an animal to prophylactically treat the animal against an infection with PCV2, an infection with PRRS virus, or an infection of both PCV2 and PRRS virus.

Description

EXAMPLES

(1) Study 1

(2) Objective

(3) The objective of the study is to evaluate efficacy and safety of live attenuated PRRS virus vaccine when dissolved in various PCV2 ORF2 vaccines, after intradermal administration. The efficacy towards protection against infection with PCV2 is evaluated by assessing anti-ORF2 serology (the anti-ORF2 antibodies are known to neutralize the PCV2 virus). The efficacy against an infection with PRRS virus is evaluated by assessing the PRRS viraemia upon challenge with a pathogenic PRRS strain, 4 weeks post vaccination.

(4) Experimental design

(5) The progeny of 10 sows was available for this study. A total of 50 animals were allotted to 5 groups of 10 piglets each. All animals were transferred to an animal facility when they were approximately 4 weeks old. Groups 1 to 4 were intradermally vaccinated using the IDAL® vaccinator into the right side of the neck. Groups 1 to 3 each received an ORF2 protein based PCV2 vaccine in which a live PRRS virus vaccine (Porcilis PRRS) is reconstituted. The various PCV2 vaccines originate from three different production runs. Each vaccine contained 9 μg of ORF2 protein per dose of the ORF2 protein (as compared to over 20 μg per dose in the commercially available Porcilis® PCV vaccine), and was based on the commercially available XSolve adjuvant (MSD Animal Health, Boxmeer, The Netherlands) to which 3% ovalbumin was added as a stabiliser. The PRRS vaccine was a freeze-dried vaccine and is reconstituted immediately before administration to contain 10.sup.45 TCID.sub.50 of virus per dose of 200 μl using the appropriate PCV2 vaccine or a diluent. Group 4 only received the PRRS vaccine and group 5 remained unvaccinated and served as control. All piglets were observed daily for clinical signs. The animals were challenge-infected with pathogenic PRRS virus (type I) when they were approximately 8 weeks old (day 28). The challenge material contained (a calculated dose of) 5.3 log 10 TCID.sub.50 of the virus in 2 ml. The material was intra-nasally administered, 1 ml per nostril. At the end of the observation period (49 days after vaccination corresponding to 21 days post challenge) all pigs were sacrificed. Blood samples (via v. jugularis) were taken from all animals individually on day 0, 14, 28 (right before challenge), 31, 35, 38, 42 and 49 and tested for the presence of PRRS virus, for antibodies against PRRSV and PCV2.

(6) Results

(7) No animals showed any clinical signs due to vaccination and rectal temperatures remained within 1.5° C. from controls. The vaccines are thus regarded safe.

(8) The results of the PCV2 serological response are given in FIG. 1. It appears that all combination vaccines induce a positive anti-ORF2 antibody response which means that the vaccines induce protective immunity against infection with wild-type PCV2.

(9) The results of the PRRS serological response are given in FIG. 2. It appears that all combination vaccines, like the commercially available PRRS vaccine, induce a positive anti-PRRS antibody response before challenge. This is an indication that the vaccines provide protection against PRRS virus infection. In FIG. 3 the viraemia data are given. It appears that all vaccines provide protection against PRRS virus infection since viraemia levels are lower than the level in the positive control animals (group 5) at each point in time.

(10) Study 2

(11) Objective

(12) The objective of the second study is to evaluate efficacy and safety of live attenuated PRRS virus vaccine when dissolved in different PCV2/Mhyo combination vaccines, after intradermal administration. The efficacy towards protection against infection with PCV2 is evaluated by assessing anti-ORF2 serology. The efficacy against infection with Mycoplasma hyopneumoniae is evaluated by comparing the serological response with that of the commercially available Mhyo vaccine Porcilis® Mhyo (MSD Animal Health, Boxmeer, The Netherlands). The efficacy against an infection with PRRS virus is evaluated by assessing the PRRs viraemia upon challenge with a pathogenic PRRS strain, 4 weeks post vaccination.

(13) Experimental Design

(14) The progeny of 10 sows was available for this study. A total of 40 animals were allotted to 4 groups of 10 piglets each. All animals were transferred to an animal facility when they were approximately 4 weeks old. Groups 1 to 4 were intradermally vaccinated using the IDAL® vaccinator into the right side of the neck. Groups 1 and 2 each received an ORF2 protein based PCV2 vaccine comprising in addition Mhyo bacterin (the same as in Porcilis M Hyo), in which combination vaccine a live PRRS virus vaccine (Porcilis PRRS) was reconstituted. The vaccine for group 1 was based on a Montanide adjuvant (IMS 251, available from SEPPIC, France) to which 3% ovalbumin is added. The vaccine of group 2 contained the same adjuvant but no ovalbumin was added. Each vaccine contained 9 μg/dose of the ORF2 protein, and Mhyo antigen at twice the concentration of the M Hyo antigen in the commercially available vaccine Porcilis® M Hyo ID ONCE. The PRRS vaccine was a freeze-dried vaccine and was reconstituted immediately before administration to contain 10.sup.45 TCID.sub.50 of virus per dose of 200 μl using the appropriate PCV2 vaccine or a diluent. Group 3 only received the PRRS vaccine and group 4 remained unvaccinated and served as control. All piglets were observed daily for clinical signs. The animals were challenge-infected with pathogenic PRRS virus (type I) when they were approximately 8 weeks old (day 28). The challenge material contained (a calculated dose of) 5.3 log 10 TCID50 of the virus in 2 ml. The material was intra-nasally administered, 1 ml per nostril. At the end of the observation period (49 days after vaccination corresponding to 21 days post challenge) all pigs were sacrificed. Blood samples (via v. jugularis) were taken from all animals individually on day 0, 14, 28 (right before challenge), 31, 35, 38, 42 and 49 and tested for the presence of PRRS virus, for antibodies against PRRSV, PCV2 and Mhyo.

(15) Results

(16) No animals showed any clinical signs due to vaccination and rectal temperatures remained within 1.5° C. from controls. The vaccines are thus regarded safe.

(17) Regarding Mhyo, the serological response of the combination vaccine appears to be comparable to that as obtainable with the commercially available vaccine Porcilis M Hyo (no numerical results depicted in a figure). It may thus be concluded that the vaccine protects against infection with Mhyo.

(18) The results of the PCV2 serological response are given in FIG. 4. It appears that the two combination vaccines induce a positive anti-ORF2 antibody response which means that the vaccines induce protection against infection with wild-type PCV2.

(19) The results of the PRRS serological response are given in FIG. 5. It appears that the two combination vaccines, like the commercially available PRRS vaccine, induce a positive anti-PRRS antibody response before challenge. This is an indication that the vaccines provide protection against PRRS virus infection. In FIG. 6 the viraemia data are given. It appears that all three vaccines provide protection against PRRS virus infection since viraemia levels are lower than the level in the positive control animals (group 4) at each point in time.