MLST Typing of Streptococcus suis Expected to Change Diagnosis, Treatment and Prevention

The addition of MLST typing to categorize Streptococcus suis is expected to change the approach taken to the diagnosis, treatment and prevention of disease associated this bacteria in pigs.

Strep suis isolates have traditionally been categorized according to the protective capsule that surrounds them but, the introduction of genetic sequencing to obtain the whole genome has opened the door to the identification of markers specially associated with virulence.

Dr. Matheus Costa, an Assistant Professor with the Western College of Veterinary Medicine and an Adjunct Professor at Utrecht University, says MLST typing looks at the genetics of strep suis to differentiate between pathogenic and non-pathogenic strains.

Clip-Dr. Matheus Costa-Western College of Veterinary Medicine:

As we include whole genome sequencing and MLST typing on our routine diagnostics that will change, for example, how we select strains for autogenous vaccination.

There has been a lot of discussion and debate around the efficacy of autogenous vaccines for Strep suis in pigs.
But, at the end of the day, if this is something people are interested in and willing to do, the use of serotyping and MLST in combination is more likely to provide a more robust or a more informed platform to decide which strains should be included in the autogenous vaccine formulation or not.

It will change the way that we understand the epidemiology of Streptococcus suis so we'll know if there are any differences between barns, within barns.

We'll be able to control when there's a new introduction in a barn that could be associated with a flareup of Streptococcus suis disease and it will also influence the way we choose strains to be included in autogenous vaccines and, who knows, in a potential future a universal vaccine as well.

Dr. Costa says we already know that sequencing is part of the tool box of veterinarians and producers when dealing with disease and it's also the next step that will help gain control of situations where Strep suis is a problem in the barn.