The prevalence of Staphylococcus colonies in the nasal cavity was investigated in 870 volunteers. A total of 248 strains of methicillin-resistant staphylococci (MRSA: 12 strains; MRC-NS: 236 strains) were isolated from 223 volunteers. Prevalence of MRSA and MRC-NS colonization was estimated to be 23-25% in any age group over 13 years old, but was higher at 40.9% in 6- to 12-year-old children and 70.0% in 1- to 5-year-old infants before entering school. Grouping of the cases of more than one methicillin-resistant staphylococci strain isolated from family members living together showed that 45 families involved. To assess the possibility that resistant strains were transmitted between family members, 96 strains isolated from these families were analyzed by pulsed-field gel electrophoresis (PFGE). The family members were grouped in combinations of “parent and child”, “husband and wife”, “brother and sister” and “grandparent and grandchild”, totaling 58 groups. Twenty four groups were found to carry methicillin-resistant strains considered to be “indistinguishable or closely related” based on the PFGE profile. In particular, the “indistinguishable” PFGE strain profiles occurred at high incidence in groups of family members younger than 13 years old, suggesting that the “child” category is considered a factor in the transmission of methicillin-resistant Staphylococcus in a family.
The present situation of infections and infectious diseases in users of home-visit nursing care were investigated using questionnaires given to personnel with responsibility for home-visit nursing care stations in Tokyo in 2005, and other areas in Japan outside Tokyo in 2006. Responses were collected from 134 home-visit nursing care stations in Tokyo and from 523 stations outside Tokyo. Analysis of the responses produced the following findings 1) More than 50% of stations had users with diagnoses of infectious diseases during one month. 2) Prevalent infections were hepatitis, wound infections, pneumonia and cystitis. 3) More than 25% of stations reported that the most common fatal infection was pneumonia. 4) More than 80% of stations had home-visit nursing care users who were treated with a urinary catheter, more than 75% had users with an ulcer, and 60% had users with a tracheotomy, indicating a high level of risk of infection among users of home-visit nursing care. These findings indicate that many compromised hosts are included among users of home-visit nursing care, so an infection control system for home-visit personnel is essential.
Blood stream infections associated with central venous catheterization are usually caused by the biofilm formed on the surface of the indwelling catheter, although the precise mechanisms are not fully understood. This study examined catheters from 12 seriously ill patients who had underlying persistent fever of over 38°C. Scanning electron microscopy revealed that 5 catheters were coated with biofilm on the surface. The biofilm was generally formed on the outside but not the inside of the catheter. Numerous bacterial cells as well as blood cells were embedded in the biofilm matrix. The fever of these patients resolved after removal of the catheters, suggesting that the fever was caused by the biofilm on the catheter. Interestingly, 4 of the 5 patients had negative blood culture and culture of the catheter tip. Candida albicans was isolated from the blood culture and the culture of catheter in one patient, and biofilm containing Candida-like cells was observed on the surface of the inside as well as the outside of the catheter. The present study confirmed that the persistent fever of patients with negative bacteriological examinations was caused by the biofilm on the catheter.
In the field of medicine, the use of gloves has reduced the risk of occupational exposure to blood. However, the rate of glove use has not significantly increased. Complaints of “numbness of fingertips” and “difficulty in performing the procedure” were investigated in personnel experienced in taking blood samples and other less experienced personnel. In addition, personnel who were wearing gloves during blood sampling were compared to other personnel who were not wearing gloves. Wearing of gloves during blood sampling was associated with high prevalence of “numb fingertips” and “difficulty in performing the procedure”. Less experienced personnel reported higher rates of “numb fingertips” and “difficulty in performing the procedure” than experienced personnel. Within the group of experienced personnel, those who always used gloves reported “numb fingertips” and “difficulty in performing the procedure” to a lesser degree than the experienced group who did not use gloves. The regular practice of wearing gloves reduces the negative effects associated with the wearing of gloves during blood sampling. Among the 14 separate steps in taking blood samples, reports of “numb fingertips” and “difficulty in performing the procedure” increased when identifying veins, applying sticking plasters, and opening packs. The inconveniences of wearing gloves could be reduced if personnel put on gloves after identifying veins and only took them off after disposing of the hypodermic needles. When personnel took blood samples with badly fitting gloves, the incidence of “numb fingertips” and “difficulty in performing the operation” was high. Therefore, operators must be provided with a range of glove sizes to avoid such problems.
Ozone gas has high oxidation power similar to that of fluorine gas. The ozone disinfection effect against various types of bacteria, the permeability of ozone gas into various materials and its effectiveness were assessed for practical sterilization of hospital linen. Disinfection effect was evaluated by testing with S. aureus and P. aeruginosa inoculated in agar medium, and determining the number of surviving bacteria. Disinfection effect of 90% or more was presumed by processing in ozone gas with CT value (product of ozone gas concentration C and contact time T) of 1,000 ppm/min. The same disinfection effect was confirmed through the action on bacteria inoculated onto a membrane filter, as a model for hospital linen processing. To confirm the permeability of the ozone gas into the hospital linen material, the density of the ozone gas was measured on the surface and inside each part of the object. Permeability of about 70% was obtained in two futons folded into four and piled. Findings also indicated that the ozone gas processing did not cause any effect on several test targets. These findings show that ozone gas has high potential for application to the disinfection of hospital linen material.
The skin protective efficacy of alcohol-based antiseptic hand gels was investigated by measuring the skin moisture in the palm, dorsum of the hand, and finger-tip of 82 nurses. No change in the hand antisepsis frequency was discovered before and after the investigation with any of the gels. The quantity of skin moisture in the palm and finger-tip increased after application of all three gels, although some differences were detected. The findings suggest that the gel has higher moisturizing effect than alcohol-containing antiseptic hand rub, leading to skin roughness prevention and less reluctance to use the gel for hand antisepsis, so is effective for preventing healthcare-associated infections.
The present study evaluated a change of appropriate handwashing. Questionnaires about hand hygiene were sent out to the hospitals affiliated to the Niigata Society of Hospital Pharmacists in 1988, 1994 and 2007. The questionnaire asked the hospital pharmacists about methods and types of hand hygiene. The basin method was common in 1988 but is not much used at present. Rubbing method with alcohol-based hand rub was more common in 1994, but scrub methods using plain soap or antiseptic agents were most common in 2007. Review of all general presentations and articles of the Japanese Society of Environmental Infections from 1992 to 2007 found hand hygiene accounted for 10% of all submissions over the past 15 years. The ratio of general presentations about hand hygiene in 2003 (15.3%) was two times higher than that of 2002 (8.7%), the year CDC announced guidelines for hand hygiene in health-care settings. CDC recommends the rubbing method with alcohol-based hand rubs in locations without water, and routine handwashing using the scrub method with soap or antiseptic agents. However, our study showed that the use of alcohol-based handrubs decreased in 2007, apparently because handwashing with water is performed in hospitals. These results suggest that routine handwashing and hygienic hand washing are now discriminated in hospitals.