Risk of nosocomial bacteria transmission: evaluation of cleaning methods of probes used for routine ultrasonography.
BACKGROUND
There exists a small but definite risk of nosocomial infection transmission attributable to ultrasonography probes and coupling gels.


OBJECTIVE
Our objective was to ascertain whether the current method of probe disinfection in between patients is adequate to prevent cross infection, and to determine the best and safest method of probe disinfection applicable during routine ultrasonography in our institution.


METHODS
Forty consecutive patients sent for routine ultrasonography at the Radiology Department of our institution in the month of January 2004 were studied. Each patient had a standardized ultrasound scan of the abdomen, after which swabs were taken from the surface of the unclean probe and after probe disinfection by single and double paper wipe cleaning method. The swabs were cultured on Blood agar to determine the characteristics of the colony forming units (CFU).


RESULTS
Forty four bacterial isolates were recovered from 37 patients who cultured positive, with MRSA constituting 36.4 %, MRCONS 22.7 %, MSSA 13.6 %, MSCONS 13.6%, Klebsiella spp 9.1% and Proteus mirabilis 4.6%. The average CFU transmitted by the unclean probe was significantly higher (P<0.05) than that transmitted by the probe after single or double paper wipe. Also, the average CFU transmitted following single and double paper wipe, in the inpatients was significantly higher (P<0.05) than in the outpatients.


CONCLUSIONS
Single paper wipe is adequate for outpatients, but for inpatients, especially those with high risk of cross infection, double paper wipe is preferred with probe thoroughly wiped until visibly clean.
Bello
T O
TO
Department of Radiology, Ladoke Akintola University Teaching Hospital, Osogbo, Nigeria. bellotope@hotmail.com
Taiwo
S S
SS
Oparinde
D P
DP
Hassan
W O
WO
Amure
J O
JO
D000005:Abdomen / Q000000981:diagnostic imaging; D001424:Bacterial Infections / Q000517:prevention & control / Q000635:transmission*; D003428:Cross Infection / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission*; D004203:Disinfection / Q000379:methods* / Q000592:standards; D004866:Equipment Contamination / Q000706:statistics & numerical data; D005782:Gels / Q000009:adverse effects; D006801:Humans; D009549:Nigeria; D011872:Radiology Department, Hospital / Q000592:standards; D012307:Risk Factors; D014463:Ultrasonography / Q000295:instrumentation*
D005782:Gels