Journalist and Author
News from the ICAAC meeting: The “Indian superbug” NDM-1 — actually a gene which encodes an enzyme which confers resistance to almost all known antibiotics — has been found for the first time in a pet, somewhere in the United States.
When you consider the close contact we have with our pets — letting them lick us, smooching them on the head, allowing them to sleep on the bed — you’ll understand why this could be such bad news. [Read more…]
Twice in the past year I’ve written about diseases that people can pick up from their household animals. They remain my highest-traffic posts (here and here) and also my most contentious. So knowing that readers respond to that topic, this recent paper caught my eye. It’s another account of what you can, possibly, catch from your pet — but for any pet owner (which includes me), it’s terribly sad.
The most numerous and passionate comments I’ve ever gotten here were responses — OK, vituperation and denunciations — to a post describing how a Pacific Northwest family caught plague from their dogs’ fleas.
So I’ll be over in the corner donning a flame-resistant bio-suit — because it turns out that, when it comes to pets on the bed, plague is not the only health risk. It’s one of many, along with hookworm, roundworm, MRSA, rabies, Chagas disease, Pasteurella, cat scratch fever, Capnocytophaga, Cryptosporidium and Cheyletiella. Oh, and bites.
Because I’ve been so behind, there’s so much to cover! So let’s dive in:
In today’s Archives of Surgery, researchers from Seattle’s Harborview Medical Center report that one simple addition to the routine of caring for trauma patients made a significant difference to the patients’ likelihood of acquiring a hospital-associated infection:
bathing them once a day with the antiseptic chlorhexidine (in an impregnated wipe). Patients who were bathed with the antiseptic wipe, compared with patients wiped down with an inert solution, had
one-fourth the likelihood of developing a catheter-related bloodstream infection and
one-third the likelihood of ventilator-associated MRSA pneumonia. Cite: Evans HL et al. Effect of Chlorhexidine Whole-Body Bathing on Hospital-Acquired Infections Among Trauma Patients.
Arch Surg. 2010;145(3):240-246.
How important are hospital-acquired infections? Here’s a piece of research from a few weeks ago that I sadly failed to blog at the time: Just
two categories of HAIs, sepsis and pneumonia, account for 48,000 deaths and $8.1 billion in health care costs in a single year. Writing in the Archives of Internal Medicine, researchers from the nonprofit project Extending the Cure analyzed 69 million hospital-discharge records issued in 40 states between 1998 and 2006. Hospital charges and number of days that patients had to stay in the hospital were
40% higher because of those infections, many of which are caused by MRSA — and all of which are completely preventable. Cite: Eber, MR et al. Clinical and Economic Outcomes Attributable to Health care-Associated Sepsis and Pneumonia.
Arch Intern Med. 2010; 170(4): 347-53.
What else could reduce the rate of MRSA infections? How about Vitamin D? South Carolina scientists analyze data from the NHANES (National Health and Nutrition Examination Survey 2001-2004), a massive database overseen by the CDC, and find
an association between low blood levels of Vit. D and the likelihood of MRSA colonization. More than 28% of the population is Vitamin D deficient. MRSA colonization is increasing in the US. Can giving Vit. D decrease MRSA carriage? More research needed. Cite: Matheson EM et al. Vitamin D and methicillin-resistant Staphylococcus aureus nasal carriage.
Scand J Infect Dis
. 2010 Mar 8. [Epub ahead of print]
And finally: Who else carries MRSA? Some unlucky pet owners have found that animals can harbor human strains, long enough at least to pass the strain back to a human whose colonization has been cleared. So it makes sense to ask whether humans who spend time with pets are carrying the bug. Last month’s Veterinary Surgery reports that the answer is Yes.
Veterinarians are carrying MRSA in very significant numbers: 17% of vets and 18% of vet technicians at an international veterinary symposium held in San Diego in 2008. Cite: Burstiner, LC et al. Methicillin-Resistant Staphylococcus aureus Colonization in Personnel Attending a Veterinary Surgery Conference.
Vet Surg. 2010 Feb;39(2):150-7.
From the research team at the University of Guelph Ontario Veterinary College — who have probably done more than any other group to elucidate MRSA in companion animals — comes a look at MRSA infections in dogs.
In order to get better data, the team used a study model that is much-employed in human epidemiology — and has often been used for MRSA — but under-employed in veterinary medicine: a case-control study matching MRSA infections against MSSA, or drug-sensitive staph. Studies matching MRSA against MSSA have been able, for instance, to show that certain (human) MRSA infections have higher death rates, keep patients in the hospital longer, and cause more healthcare expense.
The Guelph team used the same method to compare the presentation and outcome for 40 MRSA-infected dogs and 80 dogs with MSSA who were seen between 2001 and 2007 in three veterinary hospitals, in Guelph, Philadelphia and Boston. Their verdict:
MRSA is an emerging problem in dogs, and the risk factors for MRSA infections are similar to those in humans, particularly the use of IV catheters and both beta-lactam and fluoroquinolone antibiotics.
The researchers were not able to say whether MRSA in dogs causes more deaths than MSSA, because the infections that were recorded by the hospitals were mostly superficial ones in skin and ears:
Infection types for which death would be a more realistic possible outcome were limited… Comparison of mortality rates between patients with MRSA or MSSA infections would be best performed among on ly those with invasive infections and should be considered for future studies. Here, mortality rate information was obtained retrospectively and only recorded up to the time of discharge. Therefore, whether dogs died from their infections after discharge from the referral hospital, causing an underestimate of deaths, is unknown.
Dr. Scott Weese, senior author of this paper and chief of the Guelph group, has an excellent blog on infections in companion animals, called Worms and Germs. (It’s in the blogroll.) And if you are looking for further information on MRSA in pets, the best resource I know of is the UK-based, but international, Bella Moss Foundation, named for a dog that died of a MRSA infection.
