Ideally, all horses entering any stud or stable premises should be quarantined for a period of 3-4 weeks and monitored closely, particularly in the period immediately after arrival. Any horse that develops a nasal discharge or other signs consistent with strangles should be isolated and tested for the presence of, or exposure to, S. equi.
The strangles blood test can be used to identify horses that have elevated antibody responses to S. equi and have been exposed to this pathogen in the recent past, enabling the identification of potentially infectious animals before or immediately after movement. A further blood test at the end of the quarantine process can be used to identify animals that may have seroconverted since their arrival, consistent with recent exposure to S. equi. It is recommended that in order to prevent inadvertent introduction of strangles onto a premises employing quarantine measures that any quarantine batches that include seropositive animals, as well as those seroconverting whilst in quarantine, not be released until their infectious status has been shown to be negative for presence of S. equi. (see Diagnosis)
A live attenuated strangles vaccine, Equilis StrepE, was first licensed in the UK in 2005 for administration by submucosal injection. Veterinary advice should be sought to determine whether use of the vaccine is appropriate on the basis of specific risk assessment and bearing in mind that the vaccine may trigger positive results in diagnostic tests for strangles.
It is expected that a new protein subunit strangles vaccine will be licensed for use in GB and Europe in late 2021/early 2022.