Rhodococcus equi


Rhodococcus equi is soil-dwelling bacteria that infects grazing animals. R. equi causes pneumonia in foals. Clinical disease is not common in horses older than 8 months. R. equi is a facultative intracellular, nonmotile, non–spore-forming, gram positive coccobacillus (may exist as a coccus or bacillus or intermediate form). Infection occurs by inhalation of soil particles containing pathogenic R. equi, effecting the respiratory system and causing pneumonia. R. equi has significant economic consequences due to mortality, prolonged treatment, surveillance for early detection, and expensive prophyl-actic strategies. The development of clinical disease is linked to the immune system of foals; production of little to no detectable interferon (IFN-) are at a higher risk of developing pneumonia.1 Manure from pneumonic foals is the primary source of R. equi, and has the ability to contaminate the environment. A mixture of antimicrobials is the preferred treatment of R. equi infection. R. equi is best diagnosed quickly using polymerase chain reaction (PCR in order to then stop spreading of disease by keeping infected horses isolated.2 The Fluxergy Rhodococcus equi assay qualitatively detects the pathogen in equine tracheal wash or feces.

Key Benefits

Simple workflow

No sample preparation

Automated data interpretation

Sample to result in 30 minutes

Isolate contagious horses immediately

Assay Specifications

Sample Type transtracheal wash or fecal swab*
Species Equine
Storage Condition Fluxergy Card – Room temperature @ ~23° C
Fluxergy Buffers – Frozen @ -20°C
*Sample type must be specified before use. Each assay kit is sample type specific.

Kit Contents

  • 6” Rayon swab
  • Fluxergy R equi Buffer 1
  • Fluxergy R equi Buffer 2
  • Fluxergy Card

Customer supplied reagents and supplies

  • Clinical sample for testing

Sample collection method

For transtracheal wash, use sterile saline without anticoagulants to flush mucus and cells from windpipe. Only a small volume of the 5-10mL of fluid will be used for the Fluxergy R. equi test. Collect in sterile container. Store sample in refrige-rator or at 4°C if not testing immediately after sample collection. For fecal swabs, it is recommended that the head of the swab is fully coated with sample material. For optimal performance, collect feces to be tested in a sterile 2 ozspecimen cup. Fully submerge the head of the swab into the sample for 5 seconds. Place stool coated swab into the swab tube. The opposite end of the tube serves as a tight-fitting cap. Store sample in refrigerator or at 4°C if not testing immediately after sample collection.

Intended use

The Fluxergy R equi assay is a qualitative test for the rapid detection of pathogenic R equi in equine transtracheal wash and fecal swab. This assay is for Research Use Only (RUO).

Positive PCR Result: indicates that DNA or RNA of the target organism is present in the tested sample.

Negative PCR Result: indicates that DNA or RNA of the target organism was not detected in the tested sample. However, a negative PCR results may also indicate that the number of target organisms is below the limit of detection.

Warnings and Precautions

  • Fluxergy’s R equi assay is for Research Use Only (RUO). It is not intended for diagnostic use.
  • Fluxergy’s R equi assay is compatible only with the Fluxergy Analyzer Beta device.
  • All specimens should be handled as potentially infectious agents and according to universal safety precautions.
  • This Fluxergy R. equi assay is compatible only for equine transtracheal wash and fecal swab samples.
  • Contamination of the sample and kit contents may lead to erroneous results. Use aseptic technique and a clean workspace whenever possible.
  • Store Fluxergy assay kit at recommended storage temperature and conduct assay within specified environment (e.g. temperature and humidity) for optimal performance.
  • Follow appropriate specimen collection, storage and processing for optimal performance.
  • Use Fluxergy supplied swabs, reagents, pipettes and pipette tips to conduct assay for optimal performance.

Detection of Clinical Sample

Clinical sample, specifically equine transtracheal wash positive for R. equi, was tested using the Fluxergy Analyzer Beta and R. equi assay. Results showed amplification and positive agreement with the clinical reference laboratory assay.


  1. David M. Weinstock, Arthur E. Brown; Rhodococcus equi: An Emerging Pathogen, Clinical Infectious Diseases, Volume 34, Issue 10, 15 May 2002, Pages 1379–1385, https://doi.org/10.1086
  2. Stewart, A. J. (2016). Rhodococcus equi Pneumonia in Foals. Retrieved from Merck Veterinary Manual.