ABSTRACT
Contaminated hands may contribute to the transmission of pathogens. In the prevention of healthcare-associated infections the effect of disinfection methods should ideally be possible to measure in a simple way. Microbial cultivation is the reference standard, but it is a rather complicated and time-consuming procedure, and the use of swabs for measuring adenosine triphosphate (ATP) has become a much-used proxy measurement (bioluminescence). We evaluated the effect of three hand-disinfection methods on eradication of Escherichia coli from artificially contaminated hands, using cultivation and ATP measurements in parallel. ATP measurement was found to be an unsuitable method as this reflects the total amount of cellular material left on the hands, not only the viable bacteria.
ABSTRACT
The effect of alcohol hand rub was tested in eradicating Escherichia coli, and compared with hand wash using ozonized tap water or soap and water. Alcohol eradicated all bacteria in 10 out of 35 participants, but with an average (SD) of 2330 (4227) cfu/mL left after disinfection, whereas ozonized water removed all bacteria in 10 out of 55 participants, with an average of only 538 (801) cfu/mL left (P = 0.045). Soap washing was the most effective with total removal of bacteria in six out of 20 participants, with an average of 98 (139) cfu/mL (P = 0.048 and 0.018 versus ozonized water and alcohol, respectively).
Subject(s)
Bacteria/drug effects , Disinfectants/pharmacology , Hand Disinfection/methods , Hand Sanitizers/pharmacology , Soaps/pharmacology , Water/pharmacology , 2-Propanol/pharmacology , Adult , Aged , Colony Count, Microbial , Disinfectants/classification , Ethanol/pharmacology , Female , Health Personnel/statistics & numerical data , Humans , Infection Control/methods , Male , Middle Aged , Ozone/pharmacology , Young AdultABSTRACT
BACKGROUND: Hand hygiene plays a vital role in the prevention of transmission of micro-organisms. Ozone (O3) is a highly reactive gas with a broad spectrum of antimicrobial effects on bacteria, viruses, and protozoa. It can easily be produced locally in small generators, and dissolved in tap water, and quickly transmits into ordinary O2 in the surrounding air. AIM: To compare ozonized tap water and alcohol rub in decontamination of bacterially contaminated hands. METHODS: A cross-over study among 30 nursing students. Hands were artificially contaminated with Escherichia coli (ATCC 25922), then sanitized with ozonized tap water (0.8 or 4 ppm) or 3 mL standard alcohol-based rub (Antibac 85%). The transient microbes from fingers were cultivated and colony-forming units (cfu)/mL were counted. The test procedure was modified from European Standard EN 1500:2013. FINDINGS: All contaminated hands before disinfection showed cfu >30,000/mL. The mean (SD) bacterial counts in (cfu/mL) on both hands combined were 1017 (1391) after using ozonized water, and 2337 (4664) after alcohol hand disinfection. The median (range) values were 500 (0-6700) and 250 (0-16,000) respectively (non-significant difference). Twenty per cent of participants reported adverse skin effects (burning/dryness) from alcohol disinfection compared with no adverse sensations with ozone. CONCLUSION: Ozonized tap water is an effective decontaminant of E. coli, and it could be an alternative to traditional alcohol-fluid hand disinfectants both in healthcare institutions and public places. Ozonized water may be especially valuable for individuals with skin problems.
Subject(s)
Alcohols/administration & dosage , Disinfectants/administration & dosage , Escherichia coli/drug effects , Hand Disinfection/methods , Hand/microbiology , Ozone/administration & dosage , Colony Count, Microbial , Cross-Over Studies , Escherichia coli/isolation & purification , Female , Humans , Male , Students, Nursing , Water/administration & dosage , Young AdultABSTRACT
The localization and concentration of copper in cryostat sections of human fallopian tubes from women using an intrauterine contraceptive device (IUCD) and controls was determined by light microscopic- and atomic absorption spectrophotometric techniques. The copper was visually accumulated in the epithelium and the copper concentration in the tubal tissue was increased in the IUCD user group. We also measured the concentration of copper and ceruloplasmin in serum, but there was no statistical difference between the two groups studied. Our results indicate that the IUCD has effects beyond the uterine cavity. The accumulation of copper may be associated with earlier observations of the morphological changes and infiltration of inflammatory cells observed in the fallopian tube in IUCD users.
PIP: During laparoscopic sterilization at a hospital in Bergen, Norway, surgeons removed a 1 cm segment of the macroscopic isthmic portion of the fallopian tube from 40 healthy, nonpregnant women. They used light microscopic and atomic absorption spectrophometric techniques to localize and measure the concentration of copper in cryostat sections of the fallopian tubes of 20 women who had used a copper releasing IUD for more than six months and of 20 other women who used neither an IUD nor an hormonal contraceptive. Copper was visually present in the epithelium, but weakly so, in few of the biopsies from the non-IUD users. In IUD users, it accumulated throughout the epithelium and dwindled in the lamina propria. Its mean concentration in the fallopian tube was 58% higher in IUD users than non-IUD users (128.3 vs. 81.4 nmol/mg protein; p = 0.003). IUD use did not affect protein levels. The IUD affected neither the concentration of copper nor of the copper-transporting protein, ceruloplasmin, in serum. These findings suggest that the accumulation of copper in the fallopian tube in IUD users may effect morphological changes and infiltration of inflammatory cells in the fallopian tube.
