Tracing outbreaks of Streptococcus equi infection (strangles) in horses using sequence variation in the seM gene and pulsed-field gel electrophoresis

Rapid and Precise Diagnostic Tests for S. equi: An Etiologic Agent of Equine Strangles

“…A triplex quantitative multiplex PCR assay targeting the SEQ2190, eqbE genes specific to S. equi and SZIC gene specific to S. zooepidemicus has been more susceptible than culture tests and give results through 2 h from receiving the sample [26]. Molecular methods for detection and identification Streptococcus species during strangles outbreaks [44][45][46][47][48][49] are illustrated in Table (1). Discrimination of streptococci beyond the subspecies level can be carried out using different molecular methods, such as analyses of bacterial DNA digested by different enzymes and sequencing analyses. The data obtained can be used to estimate the correlation between various isolates through an outbreak, and also between various outbreaks as portion of an epidemiological investigation [26,50].…”

“…Molecular discrimination of S. equi isolates can be difficult as various strains are genetically closely related. The SeM gene contains a variable N-terminal region directly after the 5′ end signal encoding sequence (hypervariable portion) (Figure 1), which seems to be under diversifying selective pressure probably from the immune system lead to relative frequency of synonymous and non-synonymous substitutions is higher than one [5,44,46]. The sequence or allele frequencies of this anti-phagocytic gene were noticed to mutate among strains in a given period and can be used to distinguish strains in epidemiological investigations through a much higher percent of non-synonymous than synonymous single nucleotide polymorphisms variation in the hypervariable site of this gene [42,43] fibrinogen, this variability significantly interferes with the T cell response and IgA [51][52][53][54][55].…”

Reducing exposure to pathogens in the horse: a preliminary study into the survival of bacteria on a range of equine bedding types

“…The bacterium gains access to the horse through the nose or mouth and transmission of the disease occurs by direct contact with an infected horse or contaminated equipment (Lindahl et al . ).…”

“…Strangles is currently the most frequently diagnosed infectious disease of horses worldwide, responsible for high morbidity and occasional mortality of infected animals (Waller 2013). The bacterium gains access to the horse through the nose or mouth and transmission of the disease occurs by direct contact with an infected horse or contaminated equipment (Lindahl et al 2011).…”

Cloning, expression and characterization of SeM protein of Streptococcus equi subsp. equi and evaluation of its use as antigen in an indirect ELISA

“…equi synthesizes an outer membrane protein of 58 kDa encoded by the SeM gene that is particularly important due to its antiphagocytic and adherence properties. This protein has been used as a vaccine and diagnostic antigen for strangles Anzai et al, 1999;Harrington et al, 2002;Lindahl et al, 2011).…”