Dutch Girl Contracts MRSA from Friesian Foal, Recovers

A 16-year-old Dutch girl has recovered after having supposedly acquired an antibiotic-resistant staph wound infection from her Friesian foal, according to a Dutch researcher. This is only the third study reporting horse-to-human transmission of a methicillin-resistant Staphylococcus aureus (MRSA) infection reported; multiple cases were included in one of the two reports, according to said Engeline van Duijkeren, DVM, PhD, assistant professor in the department of infectious diseases and immunology at the faculty of veterinary medicine at Utrecht University. The other horse-to-human MRSA transmissions occurred in Canada.

Although rare, horse-to-human MRSA transmission does occur, van Duijkeren added.

"Horses can be carriers of MRSA, and this horse carried MRSA without any (clinical signs) of disease," van Duijkeren said. The foal had been hospitalized in a veterinary clinic two months before the girl's infection began, and it's likely where he picked up the bacteria, she added. The foal was being treated for a wound infection, which healed with antibiotics. Although no sample from the wound infection was tested for MRSA, the equine hospital regularly sees MRSA cases, which can be passed to other horses.

In the most recent case, the bacteria--which laboratory testing found to be resistant to the drugs clindamycin, erythromycin, gentamicin, kanamycin, tetracycline, and trimethoprim/sulfonamide--is believed to have entered the girl's body through an open wound (an insect bite) on her leg and colonized, van Duijkeren said. The infection resolved three months later after treatment with mupirocin, fusidic acid, and rifampin, as well as chlorhexidine shampoo baths three times daily.

The girl's foal, which tested positive as a carrier for MRSA, received no MRSA-specific treatment and tested negative for the bacteria three months later. None of the girl's family members, their cats and dogs, or their other seven horses tested positive for the disease.

It's not uncommon for humans to carry this bacterium temporarily after contact with a MRSA-positive horse; however, it's rare for people to show signs of the disease via an infection, according to van Duijkeren.

"It is important that antimicrobials are used prudently in veterinary medicine as well as in human medicine, as they are thought to be a risk factor for MRSA," van Duijkeren said, adding that humans should pay particular attention to infections that do not heal under traditional antibiotic treatment, as these could be signs of resistant bacteria.

The study, "Suspected horse-to-human transmission of MRSA ST398," was published in June in Emerging Infectious Diseases. The text is available online.

About the Author

Christa Lesté-Lasserre, MA

Christa Lesté-Lasserre is a freelance writer based in France. A native of Dallas, Texas, Lesté-Lasserre grew up riding Quarter Horses, Appaloosas, and Shetland Ponies. She holds a master’s degree in English, specializing in creative writing, from the University of Mississippi in Oxford and earned a bachelor's in journalism and creative writing with a minor in sciences from Baylor University in Waco, Texas. She currently keeps her two Trakehners at home near Paris. Follow Lesté-Lasserre on Twitter @christalestelas.

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