A vaccine developed to tackle Streptococcus suis, an economically damaging disease endemic in the global pig population, has outperformed a leading commercially available vaccine in a challenge trial.
The trial showed the vaccine candidate – developed by an international consortium including The Vaccine Group (TVG), the University of Plymouth and Moredun Scientific Limited – to be effective against a heterologous serotype of the disease.
The candidate vaccine was designed to incorporate antigens broadly present in most S. suis serotypes, with the specific intention of protecting pigs against multiple, if not all, known strains.
This is a market gap with the currently available commercial vaccines, and at present there are no proven vaccines addressing the many strains of the disease, with infected pigs being treated using a number of different antibiotics.
However, with the UK Government targeting a 50% reduction in antibiotic use in livestock by 2030 – and a global drive to reduce the threats posed by antimicrobial resistance – an effective vaccine is urgently required.
And with S. suis being a zoonotic infection that can jump to humans, causing meningitis, septicaemia and other symptoms, there will be human health benefits in addition to animal health ones.
The TVG candidate demonstrated solid clinical protection based upon several parameters, with the results following the outstanding success of a bovine respiratory syncytial virus vaccine (BRSV) candidates in cattle, also developed by TVG, that was announced in November 2025.
In addition to demonstrating superior performance to an existing vaccine, the results provide further strong validation for the TVG’s technology because:
- Positive results in pigs, alongside the previous results in cattle, show TVG’s underlying bovine herpesvirus vaccine delivery platform is highly effective across multiple species;
- The bovine herpesvirus platform has now been shown to combat different pathogen types with efficacy in bacterial diseases such as S.suis, as well as viral diseases such as BRSV.
