More on "pig MRSA" and the havoc it can do

Folks, before I get to the SHEA abstracts, one more post on ST398 in humans, and a sad and difficult story. It is the first (to my knowledge) report of ST398 spreading into a nursing home, in the January 2009 issue of Eurosurveillance Weekly.

It was very thoroughly investigated, because it took place in the Netherlands, where by national policy there is active surveillance and testing — AKA "search and destroy" — for MRSA in health care facilities.

To me it is both an object lesson in the unpredictable spread of this newly recognized organism, and also an exploration of the deep human cost of combatting it.

The nursing home, in a town called Doorn, is described as a residence for "visually and intellectually disabled" people, and it sounds like a good place, made of 35 household-like units that hold 8 residents each, with a pretty high ration of staff to residents. One resident in one unit was an adult man (age not given) who was completely blind and significantly mentally disabled. Since 2004, he had been living with hidradenitis suppurativa, a condition of painful, recurring, weeping infections of the skin that can be caused by staph. Periodically, he was treated with a variety of antibiotics — tetracycline,erythromycin, flucloxacillin, trimethoprim/sulfamethoxazole, clindamycin, minocycline, rifampicin — but none of them seem to have made much difference to the infections. (Hidradenitis is an awful condition; there are times when the only treatment is skin grafts.)

In October 2007, the regular swabs taken of his infections suddenly showed not drug-sensitive staph, but MRSA. Confirmatory swabs showed that he was colonized with MRSA in the nose, throat and groin. After analyzing whom he might have been in contact with, the home identified 43 resident and staff at risk, swabbed them all, and found 2 other residents and 3 staff members colonized. That led to another round of swabbing, of 160 people, but no other cases of colonization were found.

So, just to recap, that is the index case, with MRSA infections and colonization in various places on his body, plus five others who were only colonized.

Sequencing/typing of the isolates found that all 6 were carrying ST398, falling into one of two spa types, t2383 and the more rare t011. None of the residents or staff had had any contact with livestock. They did have play/therapy animals at the residence — rabbits, chickens and goats — but they were checked and were all negative. The source was never found.

The five who were only colonized were given 5 days of decolonization therapy: mupirocin gel (Bactroban) in the nose and showers with chlorhexidine soap (Hibiclens). Afterward, they had to be proved negative on three successive nasal cultures; the paper does not say how far apart the cultures were. Until the third negative culture, staff had to stay home, and residents were banned from group activities. Underlining that: Physically or mentally disabled adults living in an enclosed, supportive society had to be isolated from it because they acquired this bug. Just think how difficult that must have been. The paper notes: "The outbreak caused commotion among the staff members, and they had a lot of practical questions as they were unfamiliar with MRSA and an MRSA-outbreak in particular. Furthermore, it turned out that the use of gloves, surgical masks and aprons during washing and clothing was perceived as threatening by the clients."

The index case's situation is even sadder. He was given a private bath and shower, and essentially restricted to there and to his private room. He had been in group day-care, but was switched to being minded by himself. His "social contacts with other residents who lived in other units was restricted to a minimum" — presumably he was not able to be fully secluded from the other members of his household. However, anyone who came into direct contact with him — for instance, to bathe and dress him — had to be on contact precautions: gloves, aprons and surgical masks. This went on for six months while his very refractory MRSA was treated with oral antibiotics and surgical incision and drainage of his abscesses; after six months, his symptoms had not resolved, but swabs of his wounds were MRSA-negative, and some of the isolation precautions were lifted.

Underlining: Someone blind and mentally disabled, presumably fairly secure in the enclosed, supportive society of the residential home, has to be restricted from his routine, from people who are probably his friends, and from all skin-to-skin contact, for half of a year.

Now, mind you: If you or I had a relative in that home, we might want them to do exactly what they did do. It is difficult to say how well the staff might have succeeded in getting mentally disabled residents to cooperate with, for instance, hand-washing.

But this is not the first case I have heard of where the cost of protecting a group from MRSA has fallen very, very hard on one individual. I am not going to argue with the Dutch policies, but in this case, I find their unintended consequences terribly sad.