Association of Environmental Contamination in the Home With the Risk for Recurrent Community-Associated, Methicillin-Resistant Staphylococcus aureus Infection

Hygiene requirements for cleaning and disinfection of surfaces: recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute

This recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) addresses not only hospitals, but also outpatient health care facilities and compiles current evidence. The following criteria are the basis for the indications for cleaning and disinfection: Infectious bioburden and tenacity of potential pathogens on surfaces and their transmission routes, influence of disinfecting surface cleaning on the rate of nosocomial infections, interruption of cross infections due to multidrug-resistant organisms, and outbreak control by disinfecting cleaning within bundles. The criteria for the selection of disinfectants are determined by the requirements for effectiveness, the efficacy spectrum, the compatibility for humans and the environment, as well as the risk potential for the development of tolerance and resistance. Detailed instructions on the organization and implementation of cleaning and disinfection measures, including structural and equipment requirements, serve as the basis for their implementation. Since the agents for surface disinfection and disinfecting surface cleaning have been classified as biocides in Europe since 2013, the regulatory consequences are explained. As possible addition to surface disinfection, probiotic cleaning, is pointed out. In an informative appendix (only in German), the pathogen characteristics for their acquisition of surfaces, such as tenacity, infectious dose and biofilm formation, and the toxicological and ecotoxicological characteristics of microbicidal agents as the basis for their selection are explained, and methods for the evaluation of the resulting quality of cleaning or disinfecting surface cleaning are presented.

Barriers to clinical nurse participation in the internet-based home visiting program: a qualitative study

BACKGROUND

Home visits are an important part of home care. With increasing demand and the rapid development of information technology, an increasing number of regions are experimenting with the use of information technology in home visits, hoping to meet the needs of more patients through technological interventions. However, most of the current studies have focused on patient health improvement through home visits, neglecting to consider the actual experience of nurses as service providers in participating in Internet-based programs. Thus, the purpose of this research is to explore what is holding nurses back from participating after the Internet has been added to traditional home visiting programs.

METHODS

This research was designed with an exploratory-descriptive qualitative analysis method. Semistructured interviews were used to collect information on barriers to nurses' participation in the Internet-based home visiting program. Participants included 16 clinical nurses working in various hospitals in Nanjing, China. The thematic analysis method was used to analyze the information.

RESULTS

This research identified three themes and twelve subthemes that hinder clinical nurse engagement in the Internet-based home visiting program. The three themes included multiple barriers to individuals, different service modes, and emerging organizational problems.

CONCLUSIONS

As a new form of traditional home visiting program in information society, Internet-based home visiting has many shortcomings in the overall program design and service management specifications. For more patients living at home to receive quality care services, it is necessary to take more effective measures to encourage nurses' participation at three levels: nurse demand, service process, and organizational management.

Pet animals as reservoirs for spreading methicillin-resistant Staphylococcus aureus to human health

Methicillin-resistant Staphylococcus aureus (MRSA) is a strain of pathogenic bacteria that is a major problem in the world's health. Due to their frequent interaction with humans, pets are one of the main risk factors for the spread of MRSA. The possibility for zoonotic transmission exists since frequently kept dogs and cats are prone to contract MRSA and act as reservoirs for spreading MRSA. The mouth, nose, and perineum are the primary locations of MRSA colonization, according to the findings of MRSA identification tests conducted on pets. The types of MRSA clones identified in cats and dogs correlated with MRSA clones infecting humans living in the same geographic area. A significant risk factor for the colonization or transmission of MRSA is human-pet contact. An essential step in preventing the spread of MRSA from humans to animals and from animals to humans is to keep hands, clothing, and floor surfaces clean.

Comparative Effectiveness Study of Home-Based Interventions to Prevent CA-MRSA Infection Recurrence

Recurrent skin and soft tissue infections (SSTI) caused by Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) or Methicillin-Sensitive Staphylococcus aureus (CA-MSSA) present treatment challenges. This community-based trial examined the effectiveness of an evidence-based intervention (CDC Guidelines, topical decolonization, surface decontamination) to reduce SSTI recurrence, mitigate household contamination/transmission, and improve patient-reported outcomes. Participants (n = 186) were individuals with confirmed MRSA(+)/MSSA(+) SSTIs and their household members. During home visits; Community Health Workers/Promotoras provided hygiene instructions; a five-day supply of nasal mupirocin; chlorhexidine for body cleansing; and household disinfecting wipes (Experimental; EXP) or Usual Care Control (UC CON) pamphlets. Primary outcome was six-month SSTI recurrence from electronic health records (EHR). Home visits (months 0; 3) and telephone assessments (months 0; 1; 6) collected self-report data. Index patients and participating household members provided surveillance culture swabs. Secondary outcomes included household surface contamination; household member colonization and transmission; quality of life; and satisfaction with care. There were no significant differences in SSTI recurrence between EXP and UC in the intent-to-treat cohort (n = 186) or the enrolled cohort (n = 119). EXP participants showed reduced but non-significant colonization rates. EXP and UC did not differ in household member transmission, contaminated surfaces, or patient-reported outcomes. This intervention did not reduce clinician-reported MRSA/MSSA SSTI recurrence. Taken together with other recent studies that employed more intensive decolonization protocols, it is possible that a promotora-delivered intervention instructing treatment for a longer or repetitive duration may be effective and should be examined by future studies.

Individual, social, and environmental factors for infection risk among home healthcare patients: A multi-method study

There has been limited research into the individual, social, and environmental factors for infection risk among patients in the home healthcare (HHC) setting, where the infection is a leading cause of hospitalisation. The aims of this study were to (1) explore nurse perceptions of individual, social, and environmental factors for infection risk among HHC patients; and (2) identify the frequency of environmental barriers to infection prevention and control in HHC. Data were collected in 2017-2018 and included qualitative interviews with HHC nurses (n = 50) and structured observations of nurse visits to patients' homes (n = 400). Thematic analyses of interviews with nurses suggested they perceived infection risk among patients as being influenced by knowledge of and attitudes towards infection prevention and engagement in hygiene practices, receipt of support from informal caregivers and nurse interventions aimed at cultivating infection control knowledge and practices, and the home environment. Statistical analyses of observation checklists revealed nurses encountered an average of 1.7 environmental barriers upon each home visit. Frequent environmental barriers observed during visits to HHC patients included clutter (39.5%), poor lighting (38.8%), dirtiness (28.5%), and pets (17.2%). Additional research is needed to clarify inter-relationships among these factors and identify strategies for addressing each as part of a comprehensive infection control program in HHC.

Identification and application of a neutralizing epitope within alpha-hemolysin using human serum antibodies elicited by vaccination

Staphylococcus aureus (SA), especially the methicillin-resistant variant (MRSA), is becoming a serious threat to human health in hospitals and communities, making the development of an effective vaccine urgent. Alpha-hemolysin (Hla) is a key virulence factor and also a good target for the development of SA vaccines. However, the epitopes in Hla recognized by human immunity are not characterized in detail, which hinders the design of epitope-based human vaccines against SA. In this study, we collected sera from volunteers in a phase 1b clinical trial of a novel recombinant five-antigen SA vaccine (NCT03966040). Using a Luminex-based assay, we characterized the human serologic response against Hla, and identified Hla_121-138 as a neutralizing epitope. In addition, we successfully produced ferritin nanoparticles carrying the neutralizing Hla_121-138 epitope (EpNP) in E. coli. EpNP presented as homogenous nanoparticles in aqueous solution. Immunization with EpNP elicited potent hemolysis-neutralizing antibodies and conferred significant protection in a mouse model of SA skin infection. Our data suggest that EpNP, carrying the neutralizing epitope Hla_121-138, is a good candidate for a vaccine against SA.

Diversity of methicillin-resistant staphylococci among wild Lepus granatensis: first detection of mecA-MRSA in hares

MRSA in humans, pets and livestock have been widely investigated, nevertheless, there is still little information of MRSA in wild animals. Therefore, this study aimed to investigate the occurrence and antimicrobial resistance profiles of methicillin-resistant staphylococci (MRS) in wild Iberian hares and to characterize their genetic lineages. Samples from 83 wild hares (Lepus granatensis) were collected during the hunting season. Isolation of MRS was accomplish using Oxacillin Resistant Screening Agar medium with 2 mg/L of oxacillin. The susceptibility of the isolates was tested by the Kirby-Bauer disc diffusion method. The presence of resistance and virulence genes was studied by PCR. S. aureus strains were further characterized by multilocus sequence typing, agr, spa and SCCmec typing. From the 83 samples, 12 (14.45%) coagulase-negative staphylococci and 3 (3.6%) MRSA strains were isolated. Nine coagulase-negative isolates showed resistance to at least one antibiotic. One MRSA isolate showed a multidrug-resistant profile with resistances to ß-lactams, aminoglycosides, macrolides and lincosamides. All MRSA strains were ascribed to ST2855, t1190 and SCCmec type III. The frequency of MRSA strains in wild hares was low, nevertheless, the presence of MRSA in game animals is considered a public health problem and may represent a route of transmission between animals and humans.

HOME2: Household vs. Personalized Decolonization in Households of Children with Methicillin-Resistant Staphylococcus aureus Skin and Soft Tissue Infection - A Randomized Clinical Trial

BACKGROUND

A household approach to decolonization decreases skin and soft tissue infection (SSTI) incidence, though this is burdensome and costly. As prior SSTI increases risk for SSTI, we hypothesized the effectiveness of decolonization measures to prevent SSTI when targeted to household members with prior year SSTI would be non-inferior to decolonizing all household members.

METHODS

Upon completion of our 12-month observational HOME study, 102 households were enrolled in HOME2, a 12-month, randomized non-inferiority trial. Pediatric index patients with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) SSTI, their household contacts, and pets were enrolled. Households were randomized 1:1 to the Personalized (decolonization performed only by household members who experienced SSTI during the HOME study) or Household (decolonization performed by all household members) approaches. The 5-day regimen included hygiene education, twice-daily intranasal mupirocin, and daily bleach-water baths. At 5 follow-up visits in participants' homes, swabs to detect S. aureus were collected from participants, environmental surfaces, and pets; incident SSTI were ascertained.

RESULTS

Non-inferiority of the Personalized Approach was established for the primary outcome 3-month cumulative SSTI: 23 of 212 (10.8%) participants reported SSTI in Household Approach households, while 23 of 236 (9.7%) participants reported SSTI in Personalized Approach households; difference in proportions -1.1% (95% CI -6.7%, 4.5%). In multivariable analyses, prior year SSTI and baseline MRSA colonization were associated with cumulative SSTI.

CONCLUSIONS

The Personalized Approach was non-inferior to the Household Approach in preventing SSTI. Future studies should interrogate longer durations of decolonization and/or decontamination of the household environment to reduce household MRSA burden.

Environmental Methicillin-resistant Staphylococcus aureus Contamination, Persistent Colonization, and Subsequent Skin and Soft Tissue Infection

IMPORTANCE

The longitudinal association among persistent Staphylococcus aureus colonization, household environmental contamination, and recurrent skin and soft tissue infection (SSTI) is largely unexplored to date.

OBJECTIVES

To identify factors associated with persistent S aureus colonization and recurrent SSTI in households with children with community-associated methicillin-resistant S aureus (MRSA) SSTI.

DESIGN, SETTING, AND PARTICIPANTS

This 12-month prospective cohort study included 150 children with community-associated MRSA SSTI, 542 household contacts, and 154 pets enrolled from January 3, 2012, through October 20, 2015. A total of 5 quarterly home visits were made to 150 households in the St Louis, Missouri, region. Statistical analysis was performed from September 18, 2018, to January 7, 2020.

EXPOSURES

Covariates used in S aureus strain persistence and interval SSTI models included S aureus colonization and contamination measures, personal hygiene and sharing habits, health history, activities external to the home, and household characteristics (eg, cleanliness, crowding, home ownership, and pets). Serial samples to detect S aureus were collected from household members at 3 anatomic sites, from pets at 2 anatomic sites, and from environmental surfaces at 21 sites.

MAIN OUTCOMES AND MEASURES

Molecular epidemiologic findings of S aureus isolates were assessed via repetitive-sequence polymerase chain reaction. Individual persistent colonization was defined as colonization by an identical strain for 2 consecutive samplings. Longitudinal, multivariable generalized mixed-effects logistic regression models were used to assess factors associated with persistent S aureus personal colonization, environmental contamination, and interval SSTI.

RESULTS

Among 692 household members in 150 households, 326 (47%) were male and 366 (53%) were female, with a median age of 14.82 years (range, 0.05-82.25 years). Of 540 participants completing all 5 samplings, 213 (39%) were persistently colonized with S aureus, most often in the nares and with the strain infecting the index patient at enrollment. Nine pets (8%) were persistently colonized with S aureus. Participants reporting interval intranasal mupirocin application were less likely to experience persistent colonization (odds ratio [OR], 0.44; 95% credible interval [CrI], 0.30-0.66), whereas increasing strain-specific environmental contamination pressure was associated with increased individual persistent colonization (OR, 1.17; 95% CrI, 1.06-1.30). Strains with higher colonization pressure (OR, 1.47; 95% CrI, 1.25-1.71) and MRSA strains (OR, 1.57; 95% CrI, 1.16-2.19) were more likely to persist. Seventy-six index patients (53%) and 101 household contacts (19%) reported interval SSTIs. Individuals persistently colonized with MRSA (OR, 1.56; 95% CrI, 1.17-2.11), those with a history of SSTI (OR, 2.55; 95% CrI, 1.88-3.47), and index patients (OR, 1.54; 95% CrI, 1.07-2.23) were more likely to report an interval SSTI.

CONCLUSIONS AND RELEVANCE

The study findings suggest that recurrent SSTI is associated with persistent MRSA colonization of household members and contamination of environmental surfaces. Future studies may elucidate the effectiveness of specific combinations of personal decolonization and environmental decontamination efforts in eradicating persistent strains and mitigating recurrent SSTIs.

Prevention Strategies for Recurrent Community-Associated Staphylococcus aureus Skin and Soft Tissue Infections

PURPOSE OF REVIEW

Staphylococcus aureus skin and soft tissue infections (SSTI) are a major source of morbidity. More than half of patients experiencing SSTI will have at least one recurrent infection. These infections frequently cluster in households. Given the burden these infections pose to patients and healthcare, prevention strategies are of major clinical importance and represent an active area of research. Bacterial colonization is frequently an early and critical step in the pathogenesis of infection. As such, strategies to prevent reinfection have aimed to decrease staphylococcal colonization of the skin and mucus membranes, a process referred to as decolonization.

RECENT FINDINGS

Treatment of acute SSTI with incision and drainage and systemic antibiotics is the mainstay of therapy for healing of the acute infection. Systemic antibiotics also provide benefit through reduced incidence of recurrent SSTI. Education for patients and families regarding optimization of personal and household hygiene measures, and avoidance of sharing personal hygiene items, is an essential component in prevention efforts. For patients experiencing recurrent SSTI, or in households in which multiple members have experienced SSTI, decolonization should be recommended for all household members. A recommended decolonization regimen includes application of intranasal mupirocin and antiseptic body washes with chlorhexidine or dilute bleach water baths. For patients who continue to experience recurrent SSTI, periodic decolonization should be considered. Personal decolonization with topical antimicrobials and antiseptics reduces the incidence of recurrent S. aureus SSTI. Future avenues for investigation include strategies for household environmental decontamination as well as manipulation of the host microbiota.

Characterizing the molecular epidemiology of Staphylococcus aureus across and within fitness facility types

BACKGROUND

Staphylococcus aureus is a common bacterium found in the nose and throat of healthy individuals, and presents risk factors for infection and death. We investigated environmental contamination of fitness facilities with S. aureus in order to determine molecular types and antibiotic susceptibility profiles of contaminates that may be transmitted to facility patrons.

METHODS

Environmental swabs (n = 288) were obtained from several fitness facilities (n = 16) across Northeast Ohio including cross-fit type facilities (n = 4), traditional iron gyms (n = 4), community center-based facilities (n = 5), and hospital-associated facilities (n = 3). Samples were taken from 18 different surfaces at each facility and were processed within 24 h using typical bacteriological methods. Positive isolates were subjected to antibiotic susceptibility testing and molecular characterization (PVL and mecA PCR, and spa typing).

RESULTS

The overall prevalence of S. aureus on environmental surfaces in the fitness facilities was 38.2% (110/288). The most commonly colonized surfaces were the weight ball (62.5%), cable driven curl bar, and CrossFit box (62.5%), as well as the weight plates (56.3%) and treadmill handle (50%). Interestingly, the bathroom levers and door handles were the least contaminated surfaces in both male and female restroom facilities (18.8%). Community gyms (40.0%) had the highest contamination prevalence among sampled surfaces with CrossFit (38.9%), traditional gyms (38.9%), and hospital associated (33.3%) contaminated less frequently, though the differences were not significant (p = 0.875). The top spa types found overall were t008 (12.7%), t267 (10.0%), t160, t282, t338 (all at 5.5%), t012 and t442 (4.5%), and t002 (3.6%). t008 and t002 was found in all fitness facility types accept Crossfit, with t267 (25%), t548, t377, t189 (all 10.7%) the top spa types found within crossfit. All samples were resistant to benzylpenicillin, with community centers having significantly more strains resistant to oxacillin (52.8%), erythromycin (47%), clindamycin (36%), and ciprofloxacin (19%). Overall, 36.3% of isolates were multidrug resistant.

CONCLUSIONS

Our pilot study indicates that all facility types were contaminated by S. aureus and MRSA, and that additional studies are needed to characterize the microbiome structure of surfaces at different fitness facility types and the patrons at these facilities.

School environmental contamination of methicillin-sensitive Staphylococcus aureus as an independent risk factor for nasal colonization in schoolchildren: An observational, cross-sectional study

Objective

We aim to assess the similarities of proportional, phenotypic, and molecular characteristics between the school environment and schoolchildren on methicillin-sensitive S. aureus (MSSA) isolates.

Methods

A cross-sectional study was conducted between March 2016 and August 2016 in eight elementary schools in Guangzhou, China. Nasal swabs from students and environmental swabs from school environments were collected. Univariate and multivariate logistic regression analyses under a multistage stratified cluster cross-sectional survey design were performed to access the prevalence relationship and influencing factors, respectively. Phenotypic and molecular characterizations of MSSA isolates were conducted using the Kirby-Bauer disk diffusion method and polymerase chain reaction assays, respectively.

Results

In total, 1705 schoolchildren and 1240 environmental samples from 40 classes in eight elementary schools obtained between March and August 2016 were include in this study. The rates of MSSA prevalence among schoolchildren and the environment were 11.44% (195/1705) and 4.60% (57/1240), respectively. The odds ratios and 95% confidence intervals (CIs) on the prevalence of MSSA isolates were 1.11 (95% CI, 1.05–1.29; P = 0.010) and 1.04 (95% CI, 1.01–1.07; P = 0.003) for the school or class environment and students, respectively. Similar phenotypic and molecular characteristics were identified between schoolchildren and the environment. A cause and effect relationship could not be established because the study design was cross-sectional.

Conclusions

Because of the cross-sectional design, we can reveal the association between school environment and schoolchildren on MSSA, but it is not a cause and effect relationship.

The role of methicillin-resistant Staphylococcus aureus in skin and soft tissue infections

PURPOSE OF REVIEW

Methicillin-resistant Staphylococcus aureus (MRSA) has become a major public health issue worldwide over the last years. MRSA is frequently implicated in the development of skin and soft tissue infections, leading to significant increases in morbidity, mortality and overall healthcare costs.

RECENT FINDINGS

In order to face the threat of MRSA, major changes in clinical management of skin and soft tissue infections are required. The identification of populations at risk for the acquisition of infections due to MRSA, together with the improvement of the diagnostic techniques, is paramount. Moreover, a number of new antimicrobials with activity against MRSA have been recently developed and approved for the treatment of skin and soft tissue infections, however, the use of the new drugs in the wide clinical practice remains limited.

SUMMARY

We reviewed the current epidemiology of MRSA in skin and soft tissue infections, with particular focus on implications for clinical management. The potential role of new antibiotic options against MRSA infections is also discussed.

Checklist for One Health Epidemiological Reporting of Evidence (COHERE)

One Health is defined as the intersection and integration of knowledge regarding humans, animals, and the environment, yet as the One Health scientific literature expands, there is considerable heterogeneity of approach and quality of reporting in One Health studies. In addition, many researchers who publish such studies do not include or integrate data from all three domains of human, animal, and environmental health. This points to a critical need to unify guidelines for One Health studies. This report details the Checklist for One Health Epidemiological Reporting of Evidence (COHERE) to guide the design and publication format of future One Health studies. COHERE was developed by a core writing team and international expert review group that represents multiple disciplines, including human medicine, veterinary medicine, public health, allied professionals, clinical laboratory science, epidemiology, the social sciences, ecohealth and environmental health. The twin aims of the COHERE standards are to 1) improve the quality of reporting of observational or interventional epidemiological studies that collect and integrate data from humans, animals and/or vectors, and their environments; and 2) promote the concept that One Health studies should integrate knowledge from these three domains. The 19 standards in the COHERE checklist address descriptions of human populations, animal populations, environmental assessment, spatial and temporal relationships of data from the three domains, integration of analyses and interpretation, and inclusion of expertise in the research team from disciplines related to human health, animal health, and environmental health.

Development of persistent gastrointestinal S. aureus carriage in mice

One fifth to one quarter of the human population is asymptomatically, naturally and persistently colonised by Staphylococcus aureus. Observational human studies indicate that although the whole population is intermittently exposed, some individuals lose S. aureus rapidly. Others become persistent carriers, as assessed by nasal cultures, with many individuals colonised for decades. Current animal models of S. aureus colonisation are expensive and normally require antibiotics. Importantly, these animal models have not yet contributed to our poor understanding of the dichotomy in human colonisation status. Here, we identify a single strain of S. aureus found to be persistently colonising the gastrointestinal tract of BALB/c mice. Phylogenetic analyses suggest it diverged from a human ST15 lineage in the recent past. We show that murine carriage of this organism occurs in the bowel and nares, is acquired early in life, and can persist for months. Importantly, we observe the development of persistent and non-persistent gastrointestinal carriage states in genetically identical mice. We developed a needle- and antibiotic-free model in which we readily induced S. aureus colonisation of the gastrointestinal tract experimentally by environmental exposure. Using our experimental model, impact of adaptive immunity on S. aureus colonisation could be assessed. Vaccine efficacy to eliminate colonisation could also be investigated using this model.

Life After USA300: The Rise and Fall of a Superbug

The community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) epidemic in the United States is largely attributable to the meteoric rise of a single clone, referred to as USA300. This strain not only spread across the United States in just a few years to become the predominant cause of staphylococcal disease, but it also appears to have increased the overall number of skin and soft-tissue infections (SSTIs), increasing the overall disease burden. While USA300 still constitutes a major public health burden, its prevalence may be decreasing in some parts of the United States. Other than an epidemic in South America due to a closely related strain, USA300 also seems to have been largely unable to establish itself as an endemic infection in other geographic locations. While there have been several hypotheses put forward to explain the enormous success of USA300, the reasons for its failures and its potential fall remain obscure. Far from being unique to USA300, the rise and fall of specific clones of S. aureus in human populations seems to be a common process that has occurred multiple times and in multiple locations. This review charts the rise of USA300 and the evidence that suggests that it may be in decline, and it considers how best to understand the future spread, containment, and possible extinction of CA-MRSA.