Ultraviolet light C in the treatment of chronic wounds with MRSA: a case study

The prevalence of antibiotic-resistant bacteria such as methicillin-resistant Staphylococcus aureus is rapidly increasing in healthcare facilities and spreading to the community. Methicillin-resistant S. aureus colonize the skin and open wounds and can interfere with wound healing. Recent studies have shown that ultraviolet light C can kill antibiotic-resistant strains of bacteria such as methicillin-resistant S. aureus in both laboratory cultures and animal tissue. This clinical report describes the effects of ultraviolet light C on wound bioburden and closure in three people with chronic ulcers infected with methicillin-resistant S. aureus. In all three patients, ultraviolet light C treatment reduced wound bioburden and facilitated wound healing. Two patients had complete wound closure following 1 week of ultraviolet light C treatment. This case study suggests that ultraviolet light C is a promising adjunctive therapy for chronic wounds containing antibiotic-resistant bacteria such as methicillin-resistant S. aureus.     

The effects of salt concentration and growth phase on MRSA solar and germicidal ultraviolet radiation resistance

The extensive use of antimicrobial drugs has led to the widespread emergence of resistant bacterial strains. One such organism, methicillin-resistant Staphylococcus aureus, is now found extensively in both healthcare facilities and diverse community settings such as households, correctional facilities, and athletic teams. The importance of ultraviolet radiation as an adjunctive therapy to reduce bioburden and improve wound status in patients has been documented. An in vitro study to assess the effects of different types of ultraviolet radiation on antibiotic-resistant strains was conducted to provide information that will aid in the development of rational UV irradiation medical protocols. Methicillin-resistant Staphylococcus aureus was found to be sensitive to both germicidal (ultraviolet C) and solar (ultraviolet A and B) ultraviolet radiation (ultraviolet C substantially more lethal). For both types of ultraviolet radiation, as the medium concentration of sodium chloride increased, the methicillin-resistant Staphylococcus aureus cells exhibited increased sensitivity. It also was shown for both types of ultraviolet radiation that kill curves were comparable for log and stationary phase methicillin-resistant Staphylococcus aureus cells. Photoreactivation was observed for Pseudomonas aeruginosa PAO-1 but not for methicillin-resistant Staphylococcus aureus when ultraviolet C was applied to log phase cells. The Gram-negative Pseudomonas aeruginosa PAO-1 was considerably more sensitive than the Gram-positive methicillin-resistant Staphylococcus aureus to ultraviolet C radiation. The experiments reveal that medium composition exerts a substantial effect on methicillin-resistant Staphylococcus aureus ultraviolet resistance and that this species lacks photoreactivation capacity. This suggests that in a clinical setting, eradication of the bacterium may be achieved at far lower doses of ultraviolet radiation than would be indicated by treatment protocols that do not account for ionic conditions.     

Methicillin-resistant Staphylococcus aureus: an increasing problem in a diabetic foot clinic.

AIM: To study the prevalence of pathogenic organisms and the prevalence and outcome of methicillin-resistant Staphylococcus aureus (MRSA) infection in foot ulcers in diabetic patients. METHODS: A retrospective analysis of wound swabs taken from infected foot ulcers in diabetic patients, selected from an outpatient diabetic foot clinic. Seventy-five patients (79 ulcers) with positive wound swabs were included. Size of ulcer and time to healing, in particular for MRSA-infected ulcers, were measured in all patients. RESULTS: Gram-positive aerobic bacteria were the commonest micro-organism isolated (56.7%) followed by gram-negative aerobic bacteria and anaerobes (29.8% and 13.5%, respectively). Of the gram-positive aerobes, S. aureus was found most frequently and 40% were MRSA. MRSA was isolated more commonly in patients treated with antibiotics prior to the swab compared to those who had not received antibiotics (P = 0.01). Patients whose foot ulcers were infected by MRSA had longer healing time than patients whose ulcers were infected by methicillin-sensitive S. aureus (mean (range) 35.4 (19-64) and 17.8 (8-24) weeks, respectively, P = 0.03). CONCLUSION: MRSA infection is common in diabetic foot ulcers and is associated with previous antibiotic treatment and prolonged time to healing. Further studies are required to assess the need for antibiotics in treating foot ulcers in diabetes and to assess the optimum therapeutic approach to this problem.     

Study of methicillin-resistant Staphylococcus aureus colonization among intermediate-care facility patients

PURPOSE: Prevalence of methicillin-resistant Staphylococcus aureus is high in the Poitiers teaching hospital, particularly in the intermediate care facilities. We performed a survey of methicillin-resistant Staphylococcus aureus colonization in the intermediate care facilities and 265 patients were included. METHODS: Nasal, cutaneous and wound swab cultures were done at the time of admission and at the time of the patients' departure. A decolonization procedure of methicillin-resistant Staphylococcus aureus carriers was performed using nasal application of fusidic acid and different soaps for the skin. At entry, 17.7% of patients were methicillin-resistant Staphylococcus aureus carriers (of at least one location). At departure, 30.4% were methicillin-resistant Staphylococcus aureus carriers. Among methicillin-resistant Staphylococcus aureus non-carriers at entry, 24.3% became methicillin-resistant Staphylococcus aureus carriers. RESULTS: The principal risk factor of carriage was the initial presence of a wound (RR = 3.6). The incidence rate of methicillin-resistant Staphylococcus aureus infection among the 265 patients included was 3%. CONCLUSION: The systematic screening of patients at the time of admission is expensive and isolation technically hard to manage in the intermediate care facilities. The risk factor we found in this study allow us to propose a 'light' screening limited to patients with wounds.     

Screening evaluation of an ionized nanocrystalline silver dressing in chronic wound care

The successful topical treatment of chronic wounds requires adequate debridement, bacterial balance, and moisture balance. An ionized nanocrystalline silver dressing was evaluated through an uncontrolled, prospective study of a case series of 29 patients with a variety of chronic nonhealing wounds. The four arms of the study included nine patients with foot ulcers, six patients with venous stasis ulcers, two patients with pressure ulcers, and 12 patients with miscellaneous wounds. All wounds were assessed for the usual signs of clinical infection, with most of these parameters being measured and recorded. Microbiologically, bacterial load was determined via quantitative biopsies and semi-quantitative swabs. In general, the results showed a marked clinical improvement for the majority of wounds treated with the dressing. Among improved parameters included decreased exudate and decreased purulence. The quantitative bacterial biopsies did not show any decrease in organism numbers, although the semi-quantitative swabs indicated a decrease in the wound surface bacterial loading. This was indicative of the dressing's ability to reduce surface bacteria and achieve an element of bacterial balance in the superficial dermal compartment. The proposed mechanism of action for this ionized nanocrystalline based dressing is through bacterial and moisture balance within the superficial wound space compartment.     

Quantitative swab culture versus tissue biopsy: a comparison in chronic wounds

Soft tissue infection present a significant obstacle to the healing of chronic wounds. Historically, the gold standard for determining wound bacterial bioburden has been the quantitative tissue biopsy. Nevertheless, tissue biopsies are not universally used in today's healthcare setting. Likely reasons include damage to healing tissue, the lack of facilities to process tissue biopsies, significant pain in sensate soft tissue, and increased expense with this modality. More recently, quantitative tissue swab culture has been suggested as a means to determine the wound bioburden. The authors prospectively studied 38 patients with chronic wounds of various etiologies to evaluate the correlation between quantitative wound biopsy and swab culture. Of the 38 biopsies performed, 74% indicated infection. Simultaneous swab culture of these 28 biopsies indicated infection in 22 of the 28 cases for a correlation of 79%. The authors concluded that quantitative swab culture provides a valuable adjunct in the management of chronic wounds.     

Determining the effect of an oak bark formulation on methicillin-resistant staphylococcus aureus and wound healing in porcine wound models

Control of wound infections, especially those associated with methicillin-resistant Staphylococcus aureus, is necessary for the wound healing process. Selection of topical agents should be based not only on their ability to eliminate pathogenic bacteria, but also on whether they may be detrimental to tissue repair. Two randomized, controlled in vivo studies using different porcine models were conducted to evaluate the effect of a topical oak bark ointment (treatment) on 1) methicillin-resistant Staphylococcus aureus in partial-thickness wounds, and 2) healing of second-degree burn wounds. Silver sulfadiazine, oak bark ointment vehicle control (polyethylene glycol), and no treatment (untreated wounds) were used as controls in both studies. In the first study, 108 partial-thickness wounds in three animals were inoculated with a methicillin-resistant S. aureus suspension (average 6.96+/-0.4 log CFU/mL) and covered for 24 hours with a polyurethane film. After polyurethane film removal, treatments were applied twice daily and nine wounds per day (three per animal) from each treatment group were cultured after 24, 48, and 72 hours. Methicillin-resistant S. aureus colonization was lowest in the active treatment group at all three assessment times and after 72 hours ranged from (5.01+/-1.1 CFU/mL) in the treatment to (6.20+/-0.8 CFU/mL) in the vehicle control treated wounds. In the second study, treatments were applied twice daily to second-degree burn wounds (n = 720) on eight animals. Daily epithelialization assessment (n = five wounds) was performed on day 7 through 10 after wounding. At every assessment time, the proportion of wounds healed was higher in the treatment than in the control treatment groups - days 8, 9, and 10 (active versus vehicle and untreated), P <0.01; days 9 and 10 (vehicle versus untreated), P <0.001. The oak bark formulation studied reduces methicillin-resistant S aureus contamination and facilitates healing in vivo. Research to ascertain the importance of these findings for clinical practice is needed.     

Clearance of an epidemic clone of methicillin-resistant Staphylococcus aureus in a drug-use network: A follow-up study in Switzerland

Abstract Background: A single clone of methicillin-resistant Staphylococcus aureus (MRSA) was observed in a drug-use network starting in 1994, and was found to persist throughout 2001, with up to 19% MRSA colonization of intravenous drug users (IDUs). Recent clinical observations have shown low prevalences of this endemic drug clone among MRSA isolates. The goal of this study was to assess the evolution of MRSA carriage among IDUs. Methods: The survey took place from November 2008 to September 2009. Ten drug dispensary facilities took part. Demographic and clinical data including sex, history of MRSA, past hospitalization, use of antibiotics, and presence of wounds were collected. Screening of the nares, throat, and wounds was done. Results: Five hundred and fourteen swab specimens were obtained; 497 of them were nose/throat samples and 17 were wound swabs. MRSA was identified in 5 samples (1%). Four MRSA were found in nose/throat samples and 1 in a wound swab. Pulsed-field gel electrophoresis typing of the MRSA isolates revealed 2 different common endemic types: 4 were identified as the Zurich IDU clone and 1 as the Grison clone. Conclusions: The study shows a significant decline of MRSA colonization among IDUs. The underlying causes for this decline could not be determined fully, but we hypothesize a bundle of interventions as contributing: enhanced medical care, better wound management, isolation management, teaching IDUs basic hygiene techniques, and the national 'Four Pillars' policy. Hospital epidemiological policies such as pre-emptive isolation, length of isolation time, and screening procedures were adapted accordingly.     

Critical colonization--the concept under scrutiny

Infection in chronic wounds presents a major clinical challenge and is a cause of high morbidity rates. Much attention has been dedicated to identifying and managing this problem since the publication of the first article on chronic wound infection criteria in 1994. To illustrate how alteration in wound bioburden impacts pathology, the Wound Infection Continuum has been devised and subsequently modified. One stage in this continuum, critical colonization, is putatively described as a pivotal phase that occurs without inducing an overt host response. Critical colonization suggests that the concept is currently better explained from a microbiological than from a clinical perspective. The status of critically colonized wounds may change in one of several ways: 1) deteriorate to clinical infection, 2) remain in a critically colonized state, or 3) improve following appropriate intervention. Research to clearly define the term and clarify the role of bioburden in the chronic wound is needed to help clinicians recognize and implement appropriate treatment.     

Impact of antimicrobial gauze on bacterial colonies in wounds that require packing

Heavy microbial contamination has been associated with delayed wound healing and infection in both acute and chronic wounds. A prospective, randomized, 5-week controlled, open label, multicenter study was conducted to determine whether using antimicrobial gauze containing polyhexamethylene biguanide in wounds that require packing will result in a greater reduction of bacterial colony counts than using a gauze without polyhexamethylene biguanide (the control). Twenty-one subjects were randomized to the treatment or control dressing. Wounds were evenly distributed with respect to etiology and both study groups had a median baseline wound size of 7 cm2. At baseline, 15 microbial isolates were recovered and counted in treatment group wounds and 12 were recovered in the controls. At Week 1, six isolates were recovered from subjects in the polyhexamethylene biguanide antimicrobial gauze treatment group while 10 were recovered in the control. Change in polymicrobial bioburden was most prominent during the first few weeks of the study in the polyhexamethylene biguanide group. Polymicrobial counts in the treatment group remained reduced for the following three study weeks, returning to baseline at Week 4. In the control group, the number of polymicrobial cultures rose to 60% above baseline at Week 4. Two wounds of subjects randomized to the polyhexamethylene biguanide antimicrobial gauze healed; one wound in the control group healed. Polyhexamethylene biguanide antimicrobial gauze dressing could be an important adjunct to control the polymicrobial bioburden of delayed closure surgical wounds, pressure ulcers, and diabetic foot ulcers. Additional studies seem warranted.     

Identifying groups at high risk for carriage of antibiotic-resistant bacteria

BACKGROUND: No simple, cost-effective methods exist to identify patients at high risk for methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci colonization outside intensive care settings. Without such methods, colonized patients are entering hospitals undetected and transmitting these bacteria to other patients. We aimed to develop a highly sensitive, simple-to-administer prediction rule to identify subpopulations of patients at high risk for colonization on hospital admission. METHODS: We conducted a prospective cohort study of adult patients admitted to the general medical and surgical wards of a tertiary-care facility. Data were collected using electronic medical records and an investigator-administered questionnaire. Cultures of anterior nares and the perirectal area were also collected within 48 hours of admission. RESULTS: Among 699 patients who enrolled in this study, 697 underwent nasal cultures; 555, perirectal cultures; and 553, both. Patient self-report of a hospital admission in the previous year was the most sensitive variable in identifying patients colonized with methicillin-resistant Staphylococcus aureus or with either organism (sensitivity, 76% and 90%, respectively). A prediction rule requiring patients to self-report having received antibiotics and a hospital admission in the previous year would have identified 100% of patients colonized with vancomycin-resistant enterococci. In the high-risk groups defined by the prediction rule, the prevalence of colonization by methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, or either organism were 8.1%, 10.2%, and 15.0%, respectively. CONCLUSION: Patients with a self-reported previous admission within 1 year may represent a high-risk group for colonization by methicillin-resistant Staphylococcus aureus or vancomycin-resistant enterococci at hospital admission and should be considered for targeted active surveillance culturing.     

Methicillin-resistant Staphylococcus aureus in the diabetic foot clinic: a worsening problem.

AIMS: To determine if there has been a change in the prevalence of pathogenic organisms in foot ulcers in diabetic patients in 2001 compared with our previous study in 1998. METHODS: A retrospective analysis of wound swabs taken from infected foot ulcers in diabetic patients attending the outpatient clinic in the Manchester Foot Hospital over a twelve-month period. A total of 63 patients with positive wound swabs were identified. RESULTS: Gram-positive aerobic bacteria still predominate (84.2%) and the commonest single isolate remains Staphylococcus aureus (79.0%) which is higher than we previously reported. MRSA was isolated in 30.2% of the patients which is almost double the proportion of MRSA-affected patients three years ago. This did not appear to be related to prior antibiotic usage. There was no increase in hospitalisation because of MRSA infection. CONCLUSIONS: The problem of MRSA continues to increase despite the precautions taken to prevent MRSA spread. There is a need for a multi-centre study looking into the prevalence of MRSA in diabetic foot ulcer and how this can be reduced in the diabetic foot clinic.     

Nosocomial antibiotic-associated diarrhea associated with enterotoxin-producing strains of methicillin-resistant Staphylococcus aureus

OBJECTIVES: The aim of this study is to present new evidence that enterotoxin-producing strains of methicillin-resistant Staphylococcus aureus may cause nosocomial antibiotic-associated diarrhea. METHODS: We conducted a prospective study that utilized standard methods to exclude other bacterial, parasitic, and viral pathogens as causes of nosocomial diarrhea in patients with heavy growth of methicillin-resistant S. aureus in their stool. Staphylococcal enterotoxin assays were performed on S. aureus strains recovered from patients' stools and on stool specimens from affected patients. Retrospective cohort studies compared the severity of diarrhea in patients with methicillin-resistant S. aureus-associated diarrhea with that of patients whose stool did not contain the organism and with patients colonized or infected with enterotoxin-negative methicillin-resistant S. aureus strains. RESULTS: During an 18-month period, 11 patients had nosocomial antibiotic-associated diarrhea associated with enterotoxin-producing strains of methicillin-resistant S. aureus. Other common bacterial, parasitic, and viral pathogens were excluded. S. aureus strains from the 11 patients produced staphylococcal enterotoxin A, A and B, or D. Eighty-nine percent of patients had the same enterotoxin(s) in stool specimens as produced by the strain recovered from their stool. Case patients had a greater number of days of diarrhea than patients without methicillin-resistant S. aureus in their stool (p < 0.001), or randomly selected patients colonized or infected with enterotoxin-negative methicillin-resistant S. aureus (p < 0.001). CONCLUSIONS: Our findings provide evidence that enterotoxin-producing strains of methicillin-resistant S. aureus may cause nosocomial antibiotic-associated diarrhea. Greater recognition of this disease should result in more rapid and appropriate treatment of affected patients.     

Oral carriage of staphylococci in patients with rheumatoid arthritis.

OBJECTIVE: To determine the prevalence of oral staphylococcal carriage in patients with rheumatoid arthritis compared with healthy controls. METHODS: Fifty healthy adults, 25 healthy elderly volunteers and 25 patients with rheumatoid arthritis were studied. An oral rinse, tongue swab and nasal swab were collected for culture on blood agar and a range of selective agars. Isolates of staphylococci were identified and antibiotic sensitivity profiles determined by standard methods. RESULTS: Staphylococci were isolated from the mouths of 94% of the healthy adults, 24% of whom carried Staphylococcus aureus. All the healthy elderly carried oral staphylococci and 36% were colonized with S. aureus. Staphylococci were isolated from 96% of the rheumatoid arthritis patients and this group had the highest carriage rate of S. aureus (56%), significantly higher than the healthy adults (P < 0.05). In all three groups, Staphylococcus epidermidis was isolated from the mouths of > 80%. No methicillin-resistant strains of S. aureus were isolated. CONCLUSION: Oral carriage of S. aureus appears to be common in patients with rheumatoid arthritis and studies of the mouth as a source of infection in septic arthritis would be merited.     

Swab cultures accurately identify bacterial pathogens in diabetic foot wounds not involving bone.

AIMS: Current clinical practice assumes swab cultures from wounds are unreliable. However, this assumption is based upon data culled only from wounds in which osteomyelitis and/or gangrene were present. This study aimed to re-evaluate the accuracy of swab cultures vs. deep tissue cultures in diabetic wounds of varying depth and severity. METHODS: A total of 60 infected diabetic foot wounds were cultured. Two specimens were taken from each wound: superficial swab before debridement and deep tissue specimen towards the end of surgical debridement. RESULTS: In 37 wounds (62%), the micro-organisms isolated from the swab specimen and those isolated from the deep tissue specimen were identical. In another 12 wounds (20%), the swab culture contained all micro-organisms isolated from the deep tissue culture, but also contained additional micro-organisms. Analysis according to the depth of the wound, demonstrated that swabs identified all micro-organisms isolated from the deep tissue specimens in 36/40 wounds (90%) that did not extend to bone as opposed to 13/20 wounds (65%) that extended to bone. CONCLUSIONS: Swab cultures are valuable in identifying pathogens in diabetic foot wounds when bone is not involved. When surgical debridement is contraindicated or delayed, swab cultures can be used to select appropriate antibiotic therapy.     

A comparison of an antimicrobial wound cleanser to normal saline in reduction of bioburden and its effect on wound healing

Microbial bioburden in both acute and chronic wounds is an important factor in wound healing. Consequently, the reduction of bioburden to host-manageable levels, as well as the elimination of certain virulent forms of wound pathogens (regardless of their number), has become a goal of the wound care professional. A prospective, controlled clinical study using accepted sampling methods was conducted to compare the use of an antimicrobial wound cleanser (0.057% sodium hypochlorite in an isotonic saline solution) to normal saline on the reduction of bioburden and wound size. During the 2-month study, 100% of the wounds cleansed with the antimicrobial wound cleanser (n = 9) demonstrated aerobic bioburden reduction from baseline in a range from 1 to 4 logs per wound, while 56% of the wounds cleansed with normal saline (n = 9) showed an increase in aerobic bioburden levels. The proportion of wounds exhibiting a reduction in wound size was higher in the antimicrobial wound cleanser group than in the saline group. Further research to increase understanding of the relationship between wound bioburden, healing, and cleansing agents is needed.     

Bactericidal effect of ultraviolet C (UVC), direct and filtered through transparent plastic, on gram-positive cocci: an in vitro study

The prevalence of wound infections caused by multidrug-resistant (MDR) bacteria is increasing along with concern about widespread use of antibiotics. In vitro studies have shown that ultraviolet radiation, especially UVC, is both an effective bactericidal and antifungal. However, evidence about its bactericidal effect on wounds covered with transparent dressings remains inconclusive. Transparent dressings are used to retain moisture over the wound as part of an intermittent negative pressure dressing-the Limited Access Dressing (LAD) technique. Because this dressing is designed to remain in place for a number of days, an in vitro study was conducted to explore the bactericidal effect of direct and indirect UVR through a transparent 0.15-mm thick transparent polythene sheet on Gram-positive cocci. Six bacterial strains were inoculated to sheep blood agar (SBA) plates and exposed to direct and filtered UVC (254 nm) for 5, 10, 15, 20, 25, and 30 seconds with one media serving as a control (no UVC exposure). Plates were subsequently incubated for 24 hours and bacterial growth observed. Each set of experiment was repeated three times. Direct UVC was shown to have good bactericidal effect (100% eradication of organisms inoculated) at durations ranging from a minimum of 5 seconds (methicillin-resistant, coagulase-negative Staphylococcus and Streptococcus pyogenes) to a maximum of 15 seconds (methicillin-susceptible Staphylococcus aureus and Enterococci species). No bactericidal effect was observed when UVC was filtered through a 0.15-mm thick transparent polythene sheet. The results confirm the bactericidal effect of UVC in vitro and suggest that this effect can be achieved after a very short period of time. At the same time, film dressings appear to filter UVC. This may help protect skin from exposure to UVC but also limits its utility for use with the LAD technique. In vivo studies to evaluate the shortest effective UVC treatment duration and follow-up clinical studies to ascertain treatment efficacy and effectiveness are needed.     

Patterns of wound colonisation in patients with peripheral vascular disease

The bacterial colonisation of ulcers related to vascular disease, amputation sites and sites of surgical vascular repair was studied in 122 patients with vascular disorders. Wounds were graded clinically on the basis of inflammation, oedema and exudate. They were sampled at weekly intervals in order to determine the duration of colonisation. The significance of potential pathogens was assessed. Vascular ulcers were of low mean wound grade (1.87), short duration (1.58 weeks) and potential pathogens were isolated from 82% of 38 wounds. Amputation sites were of a higher mean wound grade (2.48) and longer duration (2.52 weeks) when compared to vascular ulcers. Potential pathogens were isolated from 69% of 42 amputation sites. Sites of surgical vascular repair were similar to amputation sites with respect to mean wound grade (2.33) but of a mean duration (1.69 weeks) similar to that of vascular ulcers. Potential pathogens were isolated from 50% of 42 surgical vascular repair sites but they were not evenly distributed among limb (33%), groin (55%) and abdominal wounds (71%). Coliforms were isolated from similar numbers of all wounds. Pseudomonas spp., Staphylococcus aureus and Streptococcus faecalis were evenly distributed with respect to the site of isolation. Pseudomonas spp. and S. aureus were associated more commonly with vascular ulcers and S. faecalis with sites of surgical vascular repair. The use of topical antiseptics and/or systemic antimicrobial agents had a minimal effect in reducing colonisation/infection in the wounds studied.     

Investigate of nasopharyngeal flora in highly aged patients

To clarify the bacteriological interpretation of flora in the nasopharynx of highly aged patients (n = 107), healthy nasopharyngeal swabs were obtained from subjects of advanced age. Chief pathogenic bacteria isolated from highly aged persons were coagulase negative Staphylococcus (43 strains), Corynebacterium spp. (14 strains), methicillin-susceptible Staphylococcus aureus (beta-lactamase production and non-production) (16 strains), methicillin-resistant Staphylococcus aureus (beta-lactamase production) (6 strains). Chief nonpathogenic bacteria isolated from highly aged persons were alpha-streptococcus (14 strains), Neisseria sp (3 strains). Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis which are the chief bacteria isolated from children, demonstrated only 3 strains for each bacteria. In cases showing detection of multiple detected bacteria, common combinations were non-pathogenic bacteria and weakly pathogenic bacteria and enteric bacteria and pathogenic bacteria. The differences between nasopharyngeal flora of children and highly aged persons are suspected to be due to the differences in immunological and anatomical factors. We should actively examine these factors in highly aged subjects.     

Staphylococcus aureus and wounds: a review of tea tree oil as a promising antimicrobial

Antibiotic-resistant bacteria continue to be a major health concern worldwide. In particular, Staphylococcus aureus, both methicillin-resistant and -sensitive, are of concern in their ability to cause difficult skin and underlying tissue infections. Melaleuca alternifolia oil (tea tree oil), an essential oil, has demonstrated promising efficacy in treating these infections. Tea tree oil has been used for centuries as a botanical medicine, and has only in recent decades surfaced in the scientific literature as a promising adjunctive wound treatment. Tea tree oil is antimicrobial, anti-inflammatory, and has demonstrated ability to activate monocytes. There are few apparent side effects to using tea tree oil topically in low concentrations, with contact dermatitis being the most common. Tea tree oil has been effective as an adjunctive therapy in treating osteomyelitis and infected chronic wounds in case studies and small clinical trials. There is a need for larger clinical trials to further examine efficacy of tea tree oil as an adjunctive wound therapy, as well as improved guidelines for developing plant-based medicines.