Periodic Reporting for period 3 - VACDIVA (A safe DIVA vaccine for African Swine Fever control and eradication)
Período documentado: 2022-10-01 hasta 2024-12-31
African Swine Fever (ASF) is a highly damaging viral disease of swine, causing major sanitary and socio-economic impacts. It remains present in multiple EU and non-EU countries across Europe, Asia and Africa, and continues to threaten the stability of the global pig industry. With no commercial vaccine available, control relies on early detection and strict sanitary measures, which have proven insufficient to stop its spread.
VACDIVA addressed this challenge by developing tools for ASF prevention, diagnosis and control. The project focused on: (1) producing and evaluating safe live attenuated vaccine prototypes for wild boar and domestic pigs; (2) developing and validating companion DIVA diagnostic tests; and (3) designing evidence-based control and vaccination strategies supported by epidemiological modelling.
Several promising vaccine candidates were generated and demonstrated high protection and improved safety in domestic pigs and wild boar. Molecular and serological DIVA tests were validated using experimental and field samples. Extensive epidemiological modelling, risk analysis and baiting studies were also completed, providing robust decision-support tools for future vaccination scenarios. Although full field trials could not be performed due to regulatory constraints, all preparatory and simulation work was completed and supports future regulatory pathways.
The project brought together two ASF World Reference Laboratories, EU national reference laboratories, international research centres and key industrial partners, with strong involvement from farmers’ associations and stakeholders. VACDIVA’s results substantially advance the scientific, diagnostic and strategic basis needed for future ASF vaccination programmes.
VACDIVA addressed this challenge by developing tools for ASF prevention, diagnosis and control. The project focused on: (1) producing and evaluating safe live attenuated vaccine prototypes for wild boar and domestic pigs; (2) developing and validating companion DIVA diagnostic tests; and (3) designing evidence-based control and vaccination strategies supported by epidemiological modelling.
Several promising vaccine candidates were generated and demonstrated high protection and improved safety in domestic pigs and wild boar. Molecular and serological DIVA tests were validated using experimental and field samples. Extensive epidemiological modelling, risk analysis and baiting studies were also completed, providing robust decision-support tools for future vaccination scenarios. Although full field trials could not be performed due to regulatory constraints, all preparatory and simulation work was completed and supports future regulatory pathways.
The project brought together two ASF World Reference Laboratories, EU national reference laboratories, international research centres and key industrial partners, with strong involvement from farmers’ associations and stakeholders. VACDIVA’s results substantially advance the scientific, diagnostic and strategic basis needed for future ASF vaccination programmes.
The first phase of the project focused on the evaluation of three naturally attenuated ASFV vaccine prototypes. The candidate Lv17/WB/Rie1 (genotype II) provided 100% protection in domestic pigs without clinical signs and 92% protection in orally vaccinated wild boar, representing the first evidence of a promising oral vaccine for this species. The second prototype, NH/P68 (genotype I), was adapted to the MA104 cell line and demonstrated 100% protection in domestic pigs with reduced side effects, while studies in wild boar continued. The third prototype, ASF/ARRIAH/CV-1, was characterised but had not yet undergone in vivo evaluation during the initial period. Several DIVA antigens were identified, deletion mutants were generated from Lv17/WB/Rie1 for in vivo testing, and preliminary work began on identifying suitable cell lines for vaccine production.
During the second reporting period, full-genome analyses guided the generation of 11 deletion mutants of Lv17/WB/Rie1 and one mutant of NH/P68 using CRISPR-CAS9. WSL and MA104 cell lines were advanced for production, and the Lv17/WB/Rie1-ΔCD mutant was shown to be safe in wild boar, with both low-dose/high-dose and high-dose single-administration schemes providing high protection. A preliminary production process was established, and both freeze-dried and liquid formulations were found feasible. A triplex RT-PCR assay was developed, preliminary serological DIVA tools were produced, and epidemiological modelling progressed with updated European ASF scenarios, eco-epidemiological analyses and the definition of region-specific baiting strategies for wild boar.
In the final period, a total of 17 deletion mutants were generated, including ΔCD, ΔCD-I8 and ΔCD-D3. In domestic pigs, the ΔCD prototype provided 100% protection, showed an improved safety profile, and did not transmit to contact animals; the derived mutants also maintained efficacy with enhanced safety. In wild boar, double-dose oral vaccination with ΔCD-based candidates conferred full protection under experimental conditions. For vaccine production, MA104 and IPAM cell lines were further optimised, a GMP-compliant Master Cell Seed was established and vaccine batches were confirmed to be genetically stable and suitable for lyophilisation. The triplex real-time PCR DIVA assay was adapted to a commercial format, recombinant proteins were produced for serological DIVA testing, and both molecular and serological DIVA tools were validated using experimental and field samples, including through an international proficiency test.
Substantial progress was also made in epidemiological modelling, risk mapping, wild boar movement and behaviour analyses, and ASF modelling in Europe and Asia. Field baiting studies assessed bait uptake, selectivity and deployment conditions to support future oral vaccination. Dissemination and exploitation activities included extensive stakeholder engagement, scientific communication efforts and the preparation of five patent applications related to vaccine candidates and DIVA diagnostics. Together, these results provide a strong basis for the future exploitation of the vaccine prototypes, diagnostic tools and modelling platforms developed during the project.
During the second reporting period, full-genome analyses guided the generation of 11 deletion mutants of Lv17/WB/Rie1 and one mutant of NH/P68 using CRISPR-CAS9. WSL and MA104 cell lines were advanced for production, and the Lv17/WB/Rie1-ΔCD mutant was shown to be safe in wild boar, with both low-dose/high-dose and high-dose single-administration schemes providing high protection. A preliminary production process was established, and both freeze-dried and liquid formulations were found feasible. A triplex RT-PCR assay was developed, preliminary serological DIVA tools were produced, and epidemiological modelling progressed with updated European ASF scenarios, eco-epidemiological analyses and the definition of region-specific baiting strategies for wild boar.
In the final period, a total of 17 deletion mutants were generated, including ΔCD, ΔCD-I8 and ΔCD-D3. In domestic pigs, the ΔCD prototype provided 100% protection, showed an improved safety profile, and did not transmit to contact animals; the derived mutants also maintained efficacy with enhanced safety. In wild boar, double-dose oral vaccination with ΔCD-based candidates conferred full protection under experimental conditions. For vaccine production, MA104 and IPAM cell lines were further optimised, a GMP-compliant Master Cell Seed was established and vaccine batches were confirmed to be genetically stable and suitable for lyophilisation. The triplex real-time PCR DIVA assay was adapted to a commercial format, recombinant proteins were produced for serological DIVA testing, and both molecular and serological DIVA tools were validated using experimental and field samples, including through an international proficiency test.
Substantial progress was also made in epidemiological modelling, risk mapping, wild boar movement and behaviour analyses, and ASF modelling in Europe and Asia. Field baiting studies assessed bait uptake, selectivity and deployment conditions to support future oral vaccination. Dissemination and exploitation activities included extensive stakeholder engagement, scientific communication efforts and the preparation of five patent applications related to vaccine candidates and DIVA diagnostics. Together, these results provide a strong basis for the future exploitation of the vaccine prototypes, diagnostic tools and modelling platforms developed during the project.
African swine fever (ASF) remains one of the main threats to the global swine industry, causing severe sanitary and economic losses. Despite intensive control efforts based on early detection and strict sanitary measures, the disease continues to spread, and no commercial vaccines or effective treatments are available.
VACDIVA has achieved major progress beyond the state of the art through the development and evaluation of innovative live attenuated vaccine prototypes providing high protection against genotype II ASFV in domestic pigs and wild boar. The deletion mutants generated showed improved safety, full protection under experimental conditions and no transmission to contact animals. In parallel, the project developed the first molecular and serological DIVA tools able to differentiate vaccinated from infected animals.
A significant result has been the project’s intellectual property output, with five patent applications prepared between 2022 and 2025. Four of them (EP22462011.2 EP25382353.8 EP25382354.6 PCT/EP2023/082521) are jointly owned by UCM, CSIC, VMRI, MSD and GSD, and cover ASF DIVA vaccine candidates and companion diagnostics. The fifth (EP25382355.3) was filed by FMV for an additional attenuated strain.
VACDIVA also advanced epidemiological modelling and risk-assessment approaches, supporting evidence-based vaccination and control strategies. Field baiting studies refined bait uptake and deployment options for wild boar.
These achievements have strong socio-economic relevance. Safe vaccine prototypes, validated DIVA tools and modelling platforms provide a solid basis for reducing ASF spread and mitigating economic losses, while engagement with farmers and stakeholders has increased the applicability of results. Overall, VACDIVA contributes to improved animal health, rural economic stability, global food security and preparedness for transboundary diseases.
VACDIVA has achieved major progress beyond the state of the art through the development and evaluation of innovative live attenuated vaccine prototypes providing high protection against genotype II ASFV in domestic pigs and wild boar. The deletion mutants generated showed improved safety, full protection under experimental conditions and no transmission to contact animals. In parallel, the project developed the first molecular and serological DIVA tools able to differentiate vaccinated from infected animals.
A significant result has been the project’s intellectual property output, with five patent applications prepared between 2022 and 2025. Four of them (EP22462011.2 EP25382353.8 EP25382354.6 PCT/EP2023/082521) are jointly owned by UCM, CSIC, VMRI, MSD and GSD, and cover ASF DIVA vaccine candidates and companion diagnostics. The fifth (EP25382355.3) was filed by FMV for an additional attenuated strain.
VACDIVA also advanced epidemiological modelling and risk-assessment approaches, supporting evidence-based vaccination and control strategies. Field baiting studies refined bait uptake and deployment options for wild boar.
These achievements have strong socio-economic relevance. Safe vaccine prototypes, validated DIVA tools and modelling platforms provide a solid basis for reducing ASF spread and mitigating economic losses, while engagement with farmers and stakeholders has increased the applicability of results. Overall, VACDIVA contributes to improved animal health, rural economic stability, global food security and preparedness for transboundary diseases.