| _Streptococcus equi_ subspecies _equi_ (_S. equi_) is a clonal, equine host-adapted pathogen of global importance that causes a highly contagious suppurative lymphodendopathy of the head and neck, more commonly known as Strangles. The disease is highly prevalent, can be severe and spread easily by visibly infected animals or by carrier animals that show no clinical signs of disease. Antibiotic treatment is usually ineffective. However, the majority of horses develop immunity to re-infection, suggesting that vaccination should be a feasible way to prevent the infection. Live attenuated vaccine strains of _S. equi_ are available but adverse reactions have been reported and they suffer from a short duration of immunity. Thus, a safe and effective vaccine... |
