Salmonella bacteria can be a deadly problem in horse barns, as evidenced by the outbreak at the University of Pennsylvania's New Bolton Center in May 2004. Since that outbreak, researchers have turned their attention to how the disease spreads and the best prevention methods to avoid such outbreaks in the future.
Biosecurity measures to prevent spread of salmonella
Researchers estimate that 1-2% of clinically normal horses shed salmonella bacteria in their feces, and the number likely rises when horses are stressed following an acute medical or surgical colic episode.
In a study, "Identification of predictors of salmonella shedding in adult horses presented for acute colic," which appeared in the September/October 2012 issue of the Journal of Veterinary Internal Medicine, Helen Aceto, PhD, VMD, director of biosecurity at New Bolton Center, explained that it's important to follow routine health and hygiene procedures when dealing with a colicking horse in the event the horse is a Salmonella shedder.
The authors suggest those working at a large animal clinic focus fecal-testing efforts around horses matching risk factors for bacterial shedding and take the appropriate biosecurity precautions to prevent cross contamination to other patients.
Researchers estimate that 1-2% of clinically normal horses shed salmonella bacteria in their feces. This number likely rises when horses are stressed, as they would be following an acute medical or surgical colic episode.
While most large animal hospitals conduct fecal culture testing to identify potential Salmonella shedders, test results can take several days to return, which might not allow veterinarians to begin the necessary biosecurity protocols immediately.
"These are important signs to know if you have a horse with colic, or you work in or manage a hospital that treats horses with colic," said Dallap-Schaer, an associate professor in the Department of Clinical Studies at New Bolton Center.
"The more rapidly one can identify horses likely to shed, the more effectively one can limit environmental contamination and the risk of subsequent transmission to other patients," she added. "From this study, it is probably safe to say that Salmonella shedding can be associated with more serious cases of colic."
Biosecurity helps horse owners prevent spread of salmonella:
Disinfection:
- For stalls made of varnished or painted wood, painted concrete block or any other non-porous surface, remove most of the organic matter by low-pressure hosing (less than 120 psi) with a detergent. Rinse thoroughly, then -- following label directions -- spray the walls and floor if made of brick or concrete with a phenolic disinfectant such as Tek-Trol or 1-Stroke Environ.
- If you have dirt, sand or clay floors, get up as much of the old organic matter as you can. Add fresh footing if necessary to level the surface. Spread lime to get the surface dry. Then use extra thick bedding to literally keep your horse's nose and mouth further away from possible contaminants. If you have loose rubber mats -- whether on dirt, wood, or concrete -- lift them and allow what's underneath to dry thoroughly while you scrub and disinfect the mats as you did the stall walls.
- If your stall is lined with porous raw wood -- as most stalls are -- it will be extremely difficult to disinfect by this method. You can make the walls somewhat less porous by going over all the surfaces with a stiff brush to knock the dirt off (you can also hose the walls, but they must dry thoroughly before the next step). Patch cracks and knotholes with a wood filler such as Plastic Wood. When that's hard and dry, seal the wood with a couple of coats of marine-quality varnish or polyurethane. When that's dry, you have a smooth surface you can disinfect by the method already described above.
- Minimize outside traffic, and ask anyone who must come into the barn -- veterinarians, farriers, owners -- to wear disposable booties. Minimize traffic of wheelbarrows carrying manure -- they can literally close the "fecal-oral" loop by dragging contaminated feces from the sick end of the barn to the healthy. Keep pets out of the barn.