Streptococcus suis – Page 2 – Swine in Minnesota

Antimicrobial resistance in swine respiratory bacterial pathogens in the USA

On this Monday morning, we would like to share with you this article published in Research in Veterinary Science by PhD-candidate Shivdeep Hayer advised by Dr. Julio Alvarez. The peer-reviewed publication is a summary of antimicrobial resistances (AMR) in swine respiratory isolates between 2006 and 2016.

Highlights

AMR data for bacterial swine pathogens associated with Swine Respiratory Disease Complex are lacking
AMR data on swine bacterial pathogens collected over 11 years in the U.S.A was analyzed for changes in AMR prevalence
AMR in S. suis and P. multocida isolates mostly remained low
There were statistically significant changes in AMR in A. suis and H. parasuis
Use of surrogate breakpoints can lead to different AMR estimates for certain bacteria

Streptococcus suis strains circulating in the U.S. and their association with pathogenicity

Key Points

Streptococcus suis isolates were classified into 20 different serotypes and 58 different Sequence types (ST)s.
Serotypes 1 and 1/2 were associated with higher pathogenic frequency, while ST profiles 1 and 28 were associated with higher frequency of pathogenic isolates.
The analysis of the association between pathotype, serotype, and ST showed that overall, STs were a better predictor of pathogenicity than serotypes.

Can Streptococcus suis genotype predict its pathogenicity?

PhD candidate April Estrada, working with Drs. Gebhart and Marthaler published an open-access article on Streptococcus suis in the Journal of Clinical Microbiology. Streptococcus suis is an older pathogen but its prevalence as well as its virulence have been rising lately. This study investigates if categorizing isolates into serotypes and genotypes could help predict the severity of the disease on the farm.

Distribution of pathogenic Streptococcus suis in the US

In this article written for the National Hog Farmer, PhD candidate April Estrada describes the high diversity of Streptococcus suis (S.suis) isolates.

Science Page: Antibiotic susceptibility in Pasturella multocida and Streptococcus suis isolated at the Minnesota VDL

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

Antimicrobial resistance has been a preoccupying topic for the past few years. We talked before about what the definition of antibiotic resistance is and how it can be interpreted in two different manners. This week, Dr. Alvarez from the STEMMA lab is reporting the trends in antimicrobial susceptibility observed in strains of Streptococcus suis and Pasteurella multocida isolated at the Minnesota Veterinary Diagnostic Laboratory over the past 10 years. S. suis and P. multocida are common swine pathogens that can cause severe economic losses. Knowing which antibiotics are more likely to be efficient against those bacteria can help in tackling the disease faster.

Key Points:

MN-VDL data was analyzed to study antibiotic susceptibility in clinical isolates of Pasteurella multocida and Streptococcus suis from 2006 to 2016.
Isolates were highly susceptible to Ampicillin, Ceftiofur, Enrofloxacin and Florfenicol throughout the study period.
There were no changes in antibiotic susceptibility against the antibiotics tested routinely across the study period.

The full report can be read here.