Sheets, towels, TV remotes key reservoirs for MRSA contamination

(© Andreas G. Karelias. All rights reserved.)

Surfaces in households of children with MRSA infections are often contaminated with the same strain of bacteria, according to new findings.

Contamination was found most frequently on bed linens, TV remote controls, and bathroom hand towels, Dr. Stephanie A. Fritz of Washington University School of Medicine in St. Louis and her colleagues report in JAMA Pediatrics.

MRSA stands for methicillin-resistant Staphylococcus aureus, a kind of bacteria that can't be controlled by common antibiotics. At one time, MRSA infections were mostly "caught" by hospital patients, but lately people have been acquiring it even outside of healthcare settings.

“Household environmental sources are reservoirs of Staphylococcus aureus isolates that cause infection in children,” Fritz told Reuters Health.

While the new study could not show whether the children were contaminating these surfaces, or catching the infection from the surfaces, she and her colleagues are conducting a two-year follow-up study that they hope will provide answers.

Skin and soft tissue infections with MRSA often recur, Fritz and her team note in their report. In an earlier study of theirs, treating household members of a child with MRSA, in a procedure known as "decolonization," reduced recurrence of the infection compared to decolonizing the child only - but during the next year, the infections reoccurred in half of the patients in the study.

To determine whether household surfaces might be a reservoir for infection, the researchers enrolled 50 children with active or recent community-acquired MRSA. They sampled the nostrils, armpits and groin of each child to detect colonization, as well as 21 household surfaces and pet dogs and cats. All identified strains were typed to identify relatedness within households.

The researchers found MRSA in 23 of the 50 households, with the most frequently contaminated surfaces being bed linens (18 percent), TV remotes (16 percent), and bathroom hand towels (15 percent). Twelve percent of dogs and 7 percent of cats also were colonized with MRSA.

In 20 households, the researchers identified at least one surface contaminated with the same strain as that isolated from the patient.

Cleaning frequency was not associated with the likelihood of finding S. aureus on household surfaces, but Dr. Fritz noted that study participants may not have responded accurately to questions about cleaning frequency, and also were not asked which cleaning products they used.

“These environments do likely play a role in the transmission between the household members, and may play a role in the development of infection,” Fritz said. It's not clear, though, she added, whether "targeted cleaning" of those surfaces will decrease the spread of infection.

In an editorial published with the study, Dr. Aaron Milstone of Johns Hopkins Children's Center in Baltimore wrote that about 30 percent of children who develop skin and soft tissue infections with MRSA have recurrence of the infection, he told Reuters Health.

The findings “show that there's a clear link between what people have and what's in their environment,” he said. “The big question is can we improve that, is cleaning really going to make a difference in the long term. I do applaud them for chipping away at this, because it's a big public health problem. I look forward to the next steps.”

“What I would say to my patients, which is a simple message, is it's not going to hurt to clean your house. We don't know yet if that's going to prevent the problem,” he added. “This study doesn't show that if people clean their houses compulsively and fanatically the problem is going to go away.”

The findings do show, he added, that pets are not likely to be an important reservoir of MRSA. “Don't get rid of your dog in an attempt to cure this.”