The findings from a preliminary randomized clinical trial published yesterday in JAMA suggest that treating parents who are colonized with Staphylococcus aureus could be a strategy to reduce the risk of transmitting the bacteria to newborns in intensive care units.
The results of the trial—which found that decolonizing S aureus–colonized parents reduced the risk of neonates acquiring S aureus strains that were the same as those found in their parents—are significant, because S aureus is a leading cause of healthcare-associated infections in neonatal intensive care units (NICUs), with potentially devastating consequences. Many infection prevention strategies in NICUs focus on reducing the risk of neonates acquiring the bacteria from healthcare workers or the hospital environment.
But the authors of the study say the findings indicate that parents are a major reservoir for the pathogen, and that decolonizing S aureus–colonized parents may reduce this reservoir and the risk of infection.
Novel intervention shows promise
In the double-blinded trial, conducted by clinicians and researchers at Baltimore's Johns Hopkins University School of Medicine and Johns Hopkins Bloomberg School of Public Health, parents of neonates at two NICUs were screened to see if they carried S aureus.
Parents with positive screening results were then randomized to receive either 2% intranasal mupirocin ointment and 2% chlorhexidine-impregnated cloths (the intervention group) or 2% intranasal petroleum jelly ointment and nonmedicated soap cloths (the placebo group) for 5 days. The parents were allowed to visit their child during the study period.
The primary outcome of the study was neonatal acquisition of an S aureus strain that was concordant with the strain found in their parents during pre-randomization screening (the baseline S aureus strain) within 90 days. Secondary outcomes included neonatal acquisition of any S aureus strain and neonatal S aureus infection. Overall, 236 neonate-parent pairs underwent randomization (117 to the intervention group and 119 to the placebo group), and 190 neonates were included in the final analysis.
By 90 days, 74 neonates (38.9%) had acquired an S aureus strain, of which 42 (56.8%) had a strain concordant with the parental baseline strain. But only 13 of 89 (14.6%) neonates in the intervention group acquired baseline-concordant S aureus strains, compared with 29 of 101 (28.7%) in the placebo group. The risk difference was -14.1% (95% confidence interval [CI], -30.8% to 3.9%) and the hazard ratio [HR], was 0.43 (95.2% CI, 0.16 to 0.79).
In addition, fewer neonates in the intervention group (28 of 89, 31.4%) acquired any S aureus strain than in the placebo group (46 of 101, 45.5%), showing that the decolonization strategy reduced the risk of a neonate acquiring S aureus within 90 days (HR, 0.57; 95% CI, 0.31 to 0.88). One neonate in each group developed an S aureus infection.
"These findings provide early evidence that treating S aureus–colonized parents may provide a novel intervention to reduce the risk of S aureus transmission to neonates in the NICU, a period of high risk of invasive S aureus disease," the authors of the study write.
The authors also note that, because both NICUs had S aureus surveillance and decolonization programs, the effect of the intervention on S aureus acquisition in NICUs without such programs will require further investigation. In addition, adherence to the decolonization strategy may have been overestimated.
"Further research is needed to replicate these findings and assess their generalizability," they write.
In an accompanying editorial, clinicians from Columbia University Irving Medical Center and New York-Presbyterian Hospital in New York City write that the study offers a "novel and promising strategy to address a highly relevant, often intractable, clinical problem."
See also:
Dec 30 JAMA study
Dec 30 JAMA editorial
