p.aeruginosa outbreak in an nicu 805
table 2. Summary of Results of Environmental Sampling for Pseudomonas aeruginosa Culture in a Neonatal Intensive Care Unit
Sample Type
Sink basin, stick sponge Drain, swab Water sample Faucet, swab
Other environmental samplesa
Utility inlet water
No. of Samples Collected
10 8 6 8 8
2
Positive Samples, No. (%)
10 (100) 7 (88) 5 (83) 5 (63) 1 (13)
0 (0)
aSwabs of a breast pump (n=1), breast pump kit parts used and washed by a parent (n=1), humidity outlet on an incubator (n=1), mechanical ventilator tubing in use for invasive ventilation (n=1), mechanical ventilator tubing in use for noninvasive continuous positive airway pressure (n=1), and shelves adjacent to the sink (n=3).
figure 2. Layout of neonatal intensive care unit with number of case patients occupying each room depicted. The number of case patients who occupied each room in the 7 days prior to positive culture is shown according to the legend.
A substantial percentage of environmental samples from
water, faucets, drains, sink basins, and shelves near sinks were positive for P. aeruginosa. Although isolates indistinguishable by PFGE were identified from patients and the environment, a high level of genetic diversity existed among environmental and patient isolates. This finding is consistent with a previous NICU outbreak investigation12 and with potential biofilm formation in the pipes, faucets, or drains. Biofilm promotes
genetic diversity20 and is known to form on pipes or other fixtures in stagnant water.15,21 Water in the hospital remained stagnant for 3 months after completion of hospital construc- tion, allowing ample time for biofilm formation. Flushing or disinfection of water systems might be prudent if water remains stagnant >8 hours.22–24 Daily flushing of unused taps in NICUs is recommended.25 Although water was implicated as the source, we did not
figure 3. Hand-hygiene audit results from observations in the neonatal intensive care unit (NICU), September 26–October 10, 2014. Hand-hygiene audit results by date and success rating as a percentage of successful, unsuccessful, and no-attempt observations per total number of observations per day. A hand-hygiene opportunity was considered unsuccessful if the hand-hygiene practice observed did not comply with the NICU policy at the time of observation. The NICU policy for hand hygiene was to use either soap and water or alcohol-based hand rub (ABHR) until October 2, 2014, when it was changed to reflect a preference for ABHR unless hands are visibly soiled, according to Centers for Disease Control and Prevention guidelines.
identify a definitive mechanism of exposure of patients to the water. However, opportunities for tap water exposure might have been related to hand washing and other care practices (eg, cleaning of breast pump parts). We did not identify breaches in infection control related to PICCs or ventilators; however, the presence of these devices might increase exposure to staff hands during manipulation or might be a marker for increased vulnerability to infection. Consistent with other NICU outbreaks of P. aeruginosa, case patients were more likely to be extremely low birth weight compared with the general population of NICU infants.4,7 Before our investigation, staff did not receive consistent guidance emphasizing the preferential use of ABHR over washing with soap and water, according to CDC guidelines.16 Hand washing with contaminated water by healthcare per- sonnel might have contributed to transmission. We recom- mended that the hospital revise policies for hand hygiene in accordance with CDC guidelines. In addition, given the evi- dence of water contamination, the hospital implemented a policy of using ABHR after hand washing with soap and water in the NICU, until water remediation efforts could be ensured.
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136
