Alcohol-based disinfectants are now widely used, including in some key roles for hand hygiene, but have not yet satisfied clinical needs. For example, the spread of nonenveloped viruses such as norovirus sometimes causes social problems, but alcohol-based disinfectants do not have sufficient effect against nonenveloped viruses. This study investigated inactivation of noneveloped viruses (in vitro) and skin irritation (in vivo) by a series of new alcohol-based disinfectants containing organic acids and zinc compounds. Addition of organic acids showed efficacy against the human norovirus surrogate feline calicivirus (FCV) by inactivation of 4 log reduction or more within 30 seconds of exposure time and almost the same efficacy against adenovirus as ethanol for disinfection. On the other hand, addition of organic acid and zinc compound showed efficacy for inactivation of the virus of more than 4 log reduction against FCV and adenovirus within 30 seconds. Alcohol-based formulations combined with some organic acids and zinc compound reduced skin irritation of the rabbit. We conclude that new alcohol-based disinfectants containing organic acids and zinc compounds have improved effectiveness against nonenveloped viruses and better skin care.
Urinary tract infection (UTI) and antibiotic administration were studied in 53 patients with urinary disturbance treated by clean intermittent catheterization (CIC). Further, the current method of CIC was investigated in a questionnaire, and their urine and antiseptic cotton by tested culture. The rate of UTI was 76%. Statistical studies revealed that age, daily number of CICs, and interval of change of the storage liquid of the catheter were significant risk factors for UTI. Bacterial strains were isolated from the antiseptic cotton in 17 of 37 cultures. In two of these 17 patients, bacterial strains from the cotton agreed with strains from the urine. Antibiotics were administered in 35 cases, over a long period of more than two weeks in 21 of the 35 cases. Bacterial strains isolated in 14 cases showed resistance to the antibiotics, and which were administered for less than two weeks in 7 of the 14 cases. These results suggest that a suitable method of CIC is important for preventing UTI, and will reduce administration of antibiotics and prevent development of antibiotic-resistant bacteria.
Contamination of dental surgical goggles and protective spectacles was investigated using a measuring method to detect adenosine triphosphate (ATP). Mean concentration was 11 RLU (Relative Light Unit) at the beginning of the working day, but had increased to 11,638 RLU after 1 hour (t test: p<0.05). Mean concentration on the lecture measured for comparison was 46 RLU (p<0.05). Moreover, contamination of the back of the lens section of protective spectacles was 7 RLU at the beginning of the working day, but had increased to 306 RLU after 1 hour. The cleanliness factor was nearly worse than the back of the lens of dental surgical goggles (p<0.05). Choice of optic protection against transmission of infection should consider that spectacles do not offer complete protection, so dentists should wear dental surgical goggles to perform dentistry examinations. Contamination investigation using a measuring method which evaluates ATP is both simple and quick, so can be used effectively as an index of environmental contamination in a dental clinic.
Many studies have examined the preventive effects of oral care provided by dental professionals against aspiration pneumonia in elderly nursing home residents who require care. However, few reports have evaluated routine oral care provided by nurses to inpatients. Therefore, we investigated the correlation between oral care provided to general ward patients and the incidence of fever and the detection of the etiologic agents of hospital-acquired pneumonia in the oral cavity in 69 inpatients, aged 40 years or older, who were admitted to four hospitals in Niigata and required assistance in oral care. The number and details of oral care procedures were recorded. The presence of Staphylococcus aureus, MRSA, and Pseudomonas aeruginosa in the oral cavity were quantified, and fevers of 37.5°C or higher over the previous week were recorded. The subjects were divided into two groups based on oral intake (oral intake and non-oral intake groups), and Fisher's direct probability test was used to compare their results. For the oral intake group, the incidence of fever and the detection rate of S. aureus were significantly lower for subjects who received oral care three times a day. On the other hand, for the non-oral intake group, the ratio of patients with fevers was significantly lower for those who received oral care using toothbrushes. These findings suggest that, for inpatients who ingest food orally, frequent oral care can prevent fever and opportunistic pathogen colonization in the oral cavity, and that for inpatients who do not ingest food orally, fever can be prevented by mechanical oral care using a toothbrush.
We examined the prevalence of major opportunistic pathogens identified in the dental plaque of adults/children with severe motor and intellectual disabilities who were residents of a rehabilitation and nursery center. Subsequently, oral care practice was changed to reduce the incidence of opportunistic pathogens in dental plaque expecting higher effects of disinfection, and the effectiveness was evaluated by bacteriological examination; identification of targeted organisms; and approximate number of colonies evaluated as (+), (++), (+++). Of 56 residents, 11 and 45 were cared in each of the intensive-care and day-care rooms, respectively. One to three types of targeted organisms were identified in the dental plaque of 24 residents, and the major opportunistic pathogens MRSA, Pseudomonas aeruginosa and Serratia marcescens were detected in 14(25.0%), 14(25.0%) and 5(8.9%) residents, respectively. Oral care practice was changed to two new methods for the residents in the intensive-care and day-care rooms, and bacteriological examination was performed for 20 residents in whom any of these 3 types of organisms was detected. Before the change of oral care practice, MRSA was found in 1(+++), 2(++) and 11(+) residents, P. aeruginosa in 8(+++), 5(++) and 1(+) residents, and S. marcescens(+++) in 5 residents. After the change of oral care practice, these three organisms tended to persist in the same residents, but 5 months later, MRSA was found in 0(+++), 0(++) and 7(+) residents, P. aeruginosa in 0(+++), 10(++) and 2(+) residents, and S. marcescens 3(+++) and 1(+) residents. Although the changed oral care practice was effective in removing or reducing opportunistic pathogens in dental plaque, P. aeruginosa was hard to remove. The present study indicates that further development is needed for oral care practice based on the individual condition of the oral cavity, bacterial species detected, and viable counts in adults/children with severe motor and intellectual disabilities.
One factor involved in spreading norovirus infections in facilities for the elderly is the failure to initially treat waste materials, including diarrhea and vomit, appropriately. We introduced a practical training course on treating waste materials for nurses, other employees, and cleaning staff. We evaluated course effectiveness using questionnaires. In self-evaluation of methods and procedures for treating waste materials, 90.5% of caregivers and 70-80% of food preparation, cleaning, and clerical staff stated that they applied the procedures. Among those replying to the questionnaire, 33% stated before taking the course that they “do not know unless it actually happens” how to initially detect infections. After taking the course, 66.6% replied that “they could handle it.” Entries made voluntarily by respondents included “memory remains” and “if the event happens, they could do it without hesitation,” but “they plan to do what has been instructed, but do not in actual occurrences in some cases.” These results suggest that it is difficult to achieve everything in one training course, and that better results can be expected if the course is repeated. Training in practical skills is therefore considered effective for action in the initial stage.
The antimicrobial use density (AUD) of carbapenems, proportion of carbapenem-resistant Pseudomonas aeruginosa, and cross resistance rate were investigated in patients admitted to our hospital between 2005 and 2007. Furthermore, epidemiological factors associated with the detection of carbapenem-resistant P. aeruginosa were examined. The mean AUD of all carbapenems in 2005, 2006, and 2007 was 13.63±3.43, 17.06±2.31, and 17.97±4.37, respectively, showing a significant increase. In particular, the increase in the AUD of meropenem (MEPM) was marked. The proportion of MEPM-resistant P. aeruginosa significantly increased from 6.9% in 2005 to 12.0% in 2007. The proportions of MEPM-resistant P. aeruginosa in imipenem/cilastatin(IPM/CS)-resistant and panipenem/betamipron (PAPM/BP)-resistant strains were 50 and 44.2% in 2005, respectively, and rapidly increased to 79.5 and 65.3% in 2007, respectively, suggesting an association between the resistance rate and doses of antimicrobial agents. A case-control study analysis showed that the risk factors associated with the detection of carbapenem-resistant P. aeruginosa included the usage of carbapenems (odds ratio: 7.55, 95% confidence interval: 2.96-19.23, p<0.0001) and central catheter insertion (odds ratio: 2.89, 95% confidence interval: 1.19-7.02, p=0.019). The total dose was significantly higher in the resistant group than in the sensitive group (resistant group, 16.8±11.2 g; sensitive group, 10.2±5.25 g), and the total administration period was significantly longer in the resistant group than in the sensitive group (resistant group, 17.1±11.6 day; sensitive group, 9.96±4.85 day). The maximum administration period per prescription was significantly different between the two groups (resistant group, 11.5±5.3 day ; sensitive group, 9.25±3.74 day). The results of this study suggest that unnecessary antimicrobial therapy should be avoided to prevent the appearance of antibiotic-resistant bacteria. Therefore, limiting the administration period to within 10 days may be important.