Salmonella Outbreak Report
Salmonella is the bane of existence of equine hospitals. It's the most common cause of infectious disease outbreaks, some of which can be devastating.
A report about one high-profile outbreak that occurred a couple of years ago was recently published in the Journal of Veterinary Internal Medicine (Dallap Schaer et al 2010). This was a large outbreak caused by a multidrug resistant strain of Salmonella Newport that hit the University of Pennsylvania's New Bolton Center.
- Ultimately 61 animals were infected, 54 of which were horses.
- 22 (36%) infected animals died. This occurred despite the fact that aggressive treatment was provided and cost issues were minimal because the hospital paid for treatment associated with the outbreak. That's an incredibly high rate and shows how "hot" this strain was.
- Environmental sampling during the outbreak identified persistence of the bacterium in the hospital. Because of this, and ongoing cases, the hospital had to be closed for thorough decontamination. The hospital was closed for approximately three months, and the NICU/ICU was closed for eight months.
- There was extensive renovation of some areas, including sandblasting and resurfacing of 4 cement-block barns, replacing dirt flooring with concrete, installation of a polyurethane-based flooring system in all stalls and animal handling areas, and replacing non-cleanable surfaces throughout the facility. Chlorine gas decontamination was used for the ICU/NICU.
- The financial impact was estimated at over $4 million US. That doesn't include the impact on reputation and morale.
- "A paradigm shift in the relevance of biosecurity in a veterinary teaching hospital and the establishment of a stringent infection control program were integral components of successful hospital re-opening."
A good infection control program is a key component of reducing the risk of outbreaks, but they can still happen in any facility at any time. An infection control program was present in this hospital, but it was later determined to have some weaknesses that were corrected. Analysing an outbreak after the fact and trying to correct any underlying causes is a critical component and is often overlooked. By the time the outbreak is over, people often want to immediately forget that it happened and don't want to look for causes, whether it's directed at the facility, management, protocols or personnel. The goal isn't to blame someone and penalize them, it's to find out how to prevent the problem from happening again.
I commend the authors for publishing this report. I've always taken the approach of publishing and talking about any infection control issues we've run into in our hospital. It's a double edged sword, so some people don't like the fact that I do this. It certainly can lead to negative publicity, but I think it's critical that this information be shared so that problems can be prevented in the future. We've become international leaders in some aspects of infectious diseases and infection control by aggressively pursuing and publishing our "dirty laundry." Personally, I'd much rather take my horse to a hospital that isn't afraid to talk about their issues because it shows they're paying attention, and trying to stay on top of any problems, as compared to a facility that never submits a Salmonella culture from diarrheic horses just so they can say they've never found (which isn't the same as never had) Salmonella in their building.
As I've said before, hope isn't an infection control strategy. You have to work at it to do it right.
At the ongoing
In equine hospitals, intravenous (IV) catheters are often placed in the large jugular vein in the neck of horses to make it easier for everyone (the horse included) to give the animal fluids and/or medication. However. any time the body's normal barriers (e.g. the skin) are broken (e.g. by placing a catheter through the skin into a vein), there is an increased risk of infection. Catheter site complications can range from mild inflammation of the skin around the catheter, to serious infection causing thrombosis (blockage) of the vein and abscesses.
Infectious disease surveillance is an important part of the infection control program.
As part of the 2008 Conference of the
Diarrhea is a potentially life-threatening condition in horses. It's also frustrating from a diagnostic standpoint because, even with the most complete/comprehensive testing, a cause is only identified in a minority of cases. This is true for other species too, including people, and is a reflection of the complex nature of the intestinal tract and the numerous possible causes of intestinal disease. Diagnostic testing obviously costs money, so if it gives us an answer less than half the time anyway, it begs the question - why bother? Well, here are some points to consider:
The potential PROS of molecular diagnostic testing include:
The main equIDblog page is regularly updated with posts about equine infectious disease, in a blog format. It provides information and commentaries about recent and important issues pertaining to this field. New posts will be going up every day or so, so check back regularly. Periodically there will also be "case posts", which describe a horse with a particular infectious disease, with an emphasis on explaining what the problems and issues are with similarly affected horses.
You may notice a recurring theme on equIDblog anytime we talk about infectious disease control, particularly when it comes to zoonotic diseases (those that can be transmitted between animals and people): an emphasis on handwashing. There is increasing emphasis on hand hygiene (i.e. hand washing and use of alcohol hand sanitizers) education in hospitals because the hands of healthcare workers are a major (if not the most important) means of disease transmission between patients. Despite hand hygiene being easy, cheap and effective, people rarely wash their hands as often as they should, and they often don't do it properly.
Biosecurity is a term often used in association with rearing of food animals, particularly chickens and pigs. In these types of facilities, new animals are rarely or never introduced to an established group, control of personnel access is very strict, and significant efforts are made to prevent exposure of animals to new infectious agents..jpg)

