MRSA strains live on common household surfaces, according to an article published online September 8 in JAMA Pediatrics.
NanoShield prevents the spread of germs (cross contamination) like MRSA by creating a surface which provides 99.99% inhibition of all microbes. A treated surface can inhibit germs for 90 days or longer after a single application.
The homes of many children infected with methicillin-resistant Staphylococcus aureus (MRSA) may be environments in which MRSA strains live on common household surfaces, according to an article published online September 8 in JAMA Pediatrics.
That was the case for almost half of the children with MRSA infections in a recent study, in which researchers found MRSA on bed linens, television remote controls, and bathroom hand towels. Household pets also carried MRSA strains.
Stephanie A. Fritz, MD, MSCI, from the Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, and colleagues conducted a study involving 50 children with active or recent (within 2 months) community-acquired MRSA infection.
They recruited the children and their families between January 2012 and February 2013 from St. Louis Children’s Hospital and from community practices affiliated with the Washington University Pediatric and adolescent Ambulatory Research Consortium.
The children ranged in age from 0.6 to 18.6 years (median, 3 years), 58% were boys, 64% were white, and 56% had private health insurance. Most children (84%) lived in urban areas in households of 2 to 7 people (median, 4 people). The number of household pets ranged from 1 to 9 (median, 2 pets).
Twenty-one (42%) of the children were colonized with S aureus at 1 or more body sites. Colonization was exclusively MRSA for 14 (28%) children, exclusively methicillin-susceptible S aureus (MSSA) for 6 (12%) children, and both MRSA and MSSA at different body sites for 1 child (2%).
21 Household Surfaces
The researchers conducted enrollment visits in each child’s home and administered questionnaires to collect data on medical history, prior infections, hygiene practices, and household characteristics. They collected colonization cultures from the anterior nares, axillae, and inguinal folds of each participant.
The researchers also obtained surface samples from 21 household items they presumed to be frequently handled by household members. They also tested household pets.
They recovered S aureus from at least 1 household surface for 32 (64%) of the households. They recovered exclusively MRSA in 8 (16%) households and MRSA and MSSA in 15 (30%) households, for a total of 23 (46%) households with MRSA contamination. They recovered exclusively MSSA in 9 households (18%).
MRSA was most commonly found on bed linens (18%), television remote controls (16%), and bathroom hand towels (15%).
S aureus had colonized in 6 (23%) of 26 dogs tested and 1 (7%) of 14 cats tested; 1 of colonized dogs had had a skin and soft tissue infection (SSTI) during the past 6 months. In comparison, 4 dogs out of 33 noncolonized pets had had an SSTI in the past 6 months.
In total, the researchers recovered 212 isolates of 7 distinct S aureus strains from children, pets, and household surfaces.
Of the 50 children, 20 (40%) had either a colonizing or infecting strain type that was concordant with an environmental strain recovered from a household surface. Surfaces most commonly contaminated with a concordant strain were:
- children’s bed linens (8 of 41, 20%),
- television remote controls (8 of 40, 20%),
- bathroom light switches (7 of 41, 17%),
- bathroom hand towel (5 of 31, 16%), and
- bathroom sink (6 of 41, 15%).
“Interestingly, surfaces commonly perceived to be contaminated (such as toilet seats and door handles) were not major reservoirs of MRSA,” the researchers write.
They point out that MRSA can be present on household surfaces for a long time, which is a risk not addressed in current guidelines.
They conclude, “Clinicians often recommend household hygiene measures to patients in an effort to prevent recurrent community-associated MRSA infections. Data such as ours can inform prevention strategies within the household. For example, the recommended laundering in hot water of bath towels after each use and avoiding use of bar soap may not be effective, given the low frequency with which we recovered MRSA isolates from these sources. Additional studies to specify the dynamics of longitudinal MRSA household transmission and to specify effective household decontamination strategies are needed to interrupt the spread of MRSA.”
The authors note that frequency of cleaning was not associated with the likelihood of surface contamination. In contrast, more individuals per 1000 square feet was associated with a higher proportion of surface contamination.
In an accompanying editorial, Aaron M. Milstone, MD, MHS, from the Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, Maryland, writes, “This study is provocative and raises many questions, the most important of which are as follows: How does environmental contamination contribute to the epidemic of recurrent SSTIs? Is the environment the source of exposure or reexposure that increases a child’s risk of infection, or is the environment contaminated by the infected or colonized child? Would household cleaning
enhance the effectiveness of decolonization therapy? Have decolonization strategies been limited the 6
because people are not thorough enough (eg, they do not clean their television remote controls)? This study demonstrates that the household is a reservoir of MRSA, but it does not establish a causal relationship between a contaminated environment and recurrent SSTIs.”
He calls for a prospective controlled trial to find out whether the environment increases the risk or whether infected children contaminate their environments. Until then, he writes, healthcare workers should advise families with a MRSA-infected individual of the environmental risks.
“Health care workers should be sure to inform families that up to 50% of children may develop a recurrent infection despite the use of best prevention measures,” he concludes.
This research was funded by the Children’s Discovery Institute of Washington University and St. Louis Children’s Hospital, the National Institutes of Health, and the Agency for Healthcare Research and Quality. The authors and Dr. Milstone have disclosed no relevant financial relationships.
JAMA Pediatr. Published online September 8, 2014.