Hospital outbreak of Middle East respiratory syndrome coronavirus.

BACKGROUND: In September 2012, the World Health Organization reported the first cases of pneumonia caused by the novel Middle East respiratory syndrome coronavirus (MERS-CoV). We describe a cluster of health care-acquired MERS-CoV infections. METHODS: Medical records were reviewed for clinical and demographic information and determination of potential contacts and exposures. Case patients and contacts were interviewed. The incubation period and serial interval (the time between the successive onset of symptoms in a chain of transmission) were estimated. Viral RNA was sequenced. RESULTS: Between April 1 and May 23, 2013, a total of 23 cases of MERS-CoV infection were reported in the eastern province of Saudi Arabia. Symptoms included fever in 20 patients (87%), cough in 20 (87%), shortness of breath in 11 (48%), and gastrointestinal symptoms in 8 (35%); 20 patients (87%) presented with abnormal chest radiographs. As of June 12, a total of 15 patients (65%) had died, 6 (26%) had recovered, and 2 (9%) remained hospitalized. The median incubation period was 5.2 days (95% confidence interval [CI], 1.9 to 14.7), and the serial interval was 7.6 days (95% CI, 2.5 to 23.1). A total of 21 of the 23 cases were acquired by person-to-person transmission in hemodialysis units, intensive care units, or in-patient units in three different health care facilities. Sequencing data from four isolates revealed a single monophyletic clade. Among 217 household contacts and more than 200 health care worker contacts whom we identified, MERS-CoV infection developed in 5 family members (3 with laboratory-confirmed cases) and in 2 health care workers (both with laboratory-confirmed cases). CONCLUSIONS: Person-to-person transmission of MERS-CoV can occur in health care settings and may be associated with considerable morbidity. Surveillance and infection-control measures are critical to a global public health response.

Rapid automated microscopy for microbiological surveillance of ventilator-associated pneumonia.

RATIONALE: Diagnosis of ventilator-associated pneumonia (VAP) is imprecise. OBJECTIVES: To (1) determine whether alternate-day surveillance mini-bronchoalveolar lavage (mini-BAL) in ventilated adults could reduce time to initiation of targeted treatment and (2) evaluate the potential for automated microscopy to reduce analysis time. METHODS: Adult intensive care unit patients who were anticipated to require ventilation for at least a further 48 hours were included. Mini-BALs were processed for identification, quantitation, and antibiotic susceptibility, using (1) clinical culture (50 ± 7 h) and (2) automated microscopy (∼5 h plus offline analysis). MEASUREMENTS AND MAIN RESULTS: Seventy-seven mini-BALs were performed in 33 patients. One patient (3%) was clinically diagnosed with VAP. Of 73 paired samples, culture identified 7 containing pneumonia panel bacteria (>10(4) colony-forming units/ml) from five patients (15%) (4 Staphylococcus aureus [3 methicillin-resistant S. aureus], 2 Stenotrophomonas maltophilia, 1 Klebsiella pneumoniae) and resulted in antimicrobial changes/additions to two of five (40%) of those patients. Microscopy identified 7 of 7 microbiologically positive organisms and 64 of 66 negative samples compared with culture. Antimicrobial responses were concordant in four of five comparisons. Antimicrobial changes/additions would have occurred in three of seven microscopy-positive patients (43%) had those results been clinically available in 5 hours, including one patient diagnosed later with VAP despite negative mini-BAL cultures. CONCLUSIONS: Microbiological surveillance detected infection in patients at risk for VAP independent of clinical signs, resulting in changes to antimicrobial therapy. Automated microscopy was 100% sensitive and 97% specific for high-risk pneumonia organisms compared with clinical culturing. Rapid microscopy-based surveillance may be informative for treatment and antimicrobial stewardship in patients at risk for VAP.

Triggering interventions for influenza: the ALERT algorithm.

BACKGROUND: Early, accurate predictions of the onset of influenza season enable targeted implementation of control efforts. Our objective was to develop a tool to assist public health practitioners, researchers, and clinicians in defining the community-level onset of seasonal influenza epidemics. METHODS: Using recent surveillance data on virologically confirmed infections of influenza, we developed the Above Local Elevated Respiratory Illness Threshold (ALERT) algorithm, a method to identify the period of highest seasonal influenza activity. We used data from 2 large hospitals that serve Baltimore, Maryland and Denver, Colorado, and the surrounding geographic areas. The data used by ALERT are routinely collected surveillance data: weekly case counts of laboratory-confirmed influenza A virus. The main outcome is the percentage of prospective seasonal influenza cases identified by the ALERT algorithm. RESULTS: When ALERT thresholds designed to capture 90% of all cases were applied prospectively to the 2011-2012 and 2012-2013 influenza seasons in both hospitals, 71%-91% of all reported cases fell within the ALERT period. CONCLUSIONS: The ALERT algorithm provides a simple, robust, and accurate metric for determining the onset of elevated influenza activity at the community level. This new algorithm provides valuable information that can impact infection prevention recommendations, public health practice, and healthcare delivery.

Azithromycin for prevention of exacerbations of COPD.

BACKGROUND: Acute exacerbations adversely affect patients with chronic obstructive pulmonary disease (COPD). Macrolide antibiotics benefit patients with a variety of inflammatory airway diseases. METHODS: We performed a randomized trial to determine whether azithromycin decreased the frequency of exacerbations in participants with COPD who had an increased risk of exacerbations but no hearing impairment, resting tachycardia, or apparent risk of prolongation of the corrected QT interval. RESULTS: A total of 1577 subjects were screened; 1142 (72%) were randomly assigned to receive azithromycin, at a dose of 250 mg daily (570 participants), or placebo (572 participants) for 1 year in addition to their usual care. The rate of 1-year follow-up was 89% in the azithromycin group and 90% in the placebo group. The median time to the first exacerbation was 266 days (95% confidence interval [CI], 227 to 313) among participants receiving azithromycin, as compared with 174 days (95% CI, 143 to 215) among participants receiving placebo (P<0.001). The frequency of exacerbations was 1.48 exacerbations per patient-year in the azithromycin group, as compared with 1.83 per patient-year in the placebo group (P=0.01), and the hazard ratio for having an acute exacerbation of COPD per patient-year in the azithromycin group was 0.73 (95% CI, 0.63 to 0.84; P<0.001). The scores on the St. George's Respiratory Questionnaire (on a scale of 0 to 100, with lower scores indicating better functioning) improved more in the azithromycin group than in the placebo group (a mean [±SD] decrease of 2.8±12.8 vs. 0.6±11.4, P=0.004); the percentage of participants with more than the minimal clinically important difference of -4 units was 43% in the azithromycin group, as compared with 36% in the placebo group (P=0.03). Hearing decrements were more common in the azithromycin group than in the placebo group (25% vs. 20%, P=0.04). CONCLUSIONS: Among selected subjects with COPD, azithromycin taken daily for 1 year, when added to usual treatment, decreased the frequency of exacerbations and improved quality of life but caused hearing decrements in a small percentage of subjects. Although this intervention could change microbial resistance patterns, the effect of this change is not known. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT00325897.).

Universal glove and gown use and acquisition of antibiotic-resistant bacteria in the ICU: a randomized trial.

IMPORTANCE: Antibiotic-resistant bacteria are associated with increased patient morbidity and mortality. It is unknown whether wearing gloves and gowns for all patient contact in the intensive care unit (ICU) decreases acquisition of antibiotic-resistant bacteria. OBJECTIVE: To assess whether wearing gloves and gowns for all patient contact in the ICU decreases acquisition of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) compared with usual care. DESIGN, SETTING, AND PARTICIPANTS: Cluster-randomized trial in 20 medical and surgical ICUs in 20 US hospitals from January 4, 2012, to October 4, 2012. INTERVENTIONS: In the intervention ICUs, all health care workers were required to wear gloves and gowns for all patient contact and when entering any patient room. MAIN OUTCOMES AND MEASURES: The primary outcome was acquisition of MRSA or VRE based on surveillance cultures collected on admission and discharge from the ICU. Secondary outcomes included individual VRE acquisition, MRSA acquisition, frequency of health care worker visits, hand hygiene compliance, health care­associated infections, and adverse events. RESULTS: From the 26,180 patients included, 92,241 swabs were collected for the primary outcome. Intervention ICUs had a decrease in the primary outcome of MRSA or VRE from 21.35 acquisitions per 1000 patient-days (95% CI, 17.57 to 25.94) in the baseline period to 16.91 acquisitions per 1000 patient-days (95% CI, 14.09 to 20.28) in the study period, whereas control ICUs had a decrease in MRSA or VRE from 19.02 acquisitions per 1000 patient-days (95% CI, 14.20 to 25.49) in the baseline period to 16.29 acquisitions per 1000 patient-days (95% CI, 13.48 to 19.68) in the study period, a difference in changes that was not statistically significant (difference, −1.71 acquisitions per 1000 person-days, 95% CI, −6.15 to 2.73; P = .57). For key secondary outcomes, there was no difference in VRE acquisition with the intervention (difference, 0.89 acquisitions per 1000 person-days; 95% CI, −4.27 to 6.04, P = .70), whereas for MRSA, there were fewer acquisitions with the intervention (difference, −2.98 acquisitions per 1000 person-days; 95% CI, −5.58 to −0.38; P = .046). Universal glove and gown use also decreased health care worker room entry (4.28 vs 5.24 entries per hour, difference, −0.96; 95% CI, −1.71 to −0.21, P = .02), increased room-exit hand hygiene compliance (78.3% vs 62.9%, difference, 15.4%; 95% CI, 8.99% to 21.8%; P = .02) and had no statistically significant effect on rates of adverse events (58.7 events per 1000 patient days vs 74.4 events per 1000 patient days; difference, −15.7; 95% CI, −40.7 to 9.2, P = .24). CONCLUSIONS AND RELEVANCE: The use of gloves and gowns for all patient contact compared with usual care among patients in medical and surgical ICUs did not result in a difference in the primary outcome of acquisition of MRSA or VRE. Although there was a lower risk of MRSA acquisition alone and no difference in adverse events, these secondary outcomes require replication before reaching definitive conclusions. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT0131821.

Long-term impact of fluoroquinolone-sparing strategies for empirical treatment of acute uncomplicated cystitis among ambulatory patients.

Background: Acute uncomplicated cystitis is common among outpatients and frequently leads to antibiotic prescriptions, making urinary tract infections (UTIs) an important area for antimicrobial stewardship initiatives. Infectious Disease Society of America (IDSA) guidelines promote alternative agents in place of fluoroquinolones for acute uncomplicated cystitis. Despite IDSA guidance, adherence to the guideline remains low in the United States (US). Several studies have described interventions to improve guideline-concordant prescribing for UTIs. However, the long-term sustainability and impact of fluoroquinolone (FLQ)-sparing strategies on community antimicrobial resistance and treatment outcomes are unknown. The objectives of this study were to characterize current antibiotic prescribing patterns, treatment failures and Escherichia coli resistance rates in a setting which instituted FLQ sparing strategies for UTIs in 2007. Methods: Retrospective cohort study of women aged ⩾ 18 diagnosed with acute uncomplicated cystitis based on International Classification of Diseases, 10th Revision (ICD-10) codes were included. Data were abstracted for ambulatory visits over a 6-month period, January 2018 to June 2018, at a large urban health care system. Treatment decisions were made by individual providers, and data were analyzed retrospectively. Nitrofurantoin (NFT) resistance was obtained from the institutional antibiogram and patient-level data. Treatment failure was defined as the need for a different antibiotic for UTI within 28 days of the original prescription. Results: NFT was the most frequently prescribed antibiotic (n = 386, 71.6%) of empiric antibiotic prescriptions for UTIs. FLQs comprised 4.6% of all antibiotic prescriptions (n = 25). Treatment failure rate was 2.3% in patients treated with NFT. Urine culture was ordered for only 26.8% of patients. Among the small group of patients with cultures ordered, E. coli remained 98.5% susceptible to NFT. Conclusions: This study is the first to report significantly low rates (4.6%) of FLQ prescribing for acute uncomplicated cystitis. Treatment failure rate was low with empiric NFT. Increased NFT resistance among E. coli was not observed at the institution or among the subset of patients with E. coli positive urine cultures. These findings support current IDSA treatment guidance for uncomplicated cystitis.

Impact of mandatory vaccination of healthcare personnel on rates of influenza and other viral respiratory pathogens.

OBJECTIVE: The implementation of mandatory influenza vaccination policies among healthcare personnel (HCP) is controversial. Thus, we examined the affect of mandatory influenza vaccination policies among HCP working in outpatient settings. SETTING: Four Veterans' Affairs (VA) health systems and three non-VA medical centers. METHODS: We analyzed rates of influenza and other viral causes of respiratory infections among HCP working in outpatient sites at 4 VA health systems without mandatory influenza vaccination policies and 3 non-VA health systems with mandatory influenza vaccination policies. RESULTS: Influenza vaccination was associated with a decreased risk of influenza (odds ratio, 0.17; 95% confidence interval [CI], 0.13-0.22) but an increased risk of other respiratory viral infections (incidence rate ratio, 1.26; 95% CI, 1.02-1.57). CONCLUSIONS: Our fitted regression models suggest that if influenza vaccination rates in clinics where vaccination was not mandated had equalled those where vaccine was mandated, HCP influenza infections would have been reduced by 52.1% (95% CI, 51.3%-53.0%). These observations, their possible causes, and additional strategies to reduce influenza and other viral respiratory illnesses among HCP working in ambulatory clinics warrant further investigation.

Propionibacterium acnes infection as an occult cause of postoperative shoulder pain: a case series.

BACKGROUND: Infections after shoulder surgery are potentially devastating complications. Propionibacterium acnes is recognized as a causal agent in shoulder infections. The clinical presentation is usually insidious and nonspecific, but a P. acnes infection could be an occult cause of postoperative shoulder pain. QUESTIONS/PURPOSES: What are the clinical and microbiologic characteristics of a postsurgical P. acnes shoulder infection and how should it be addressed? PATIENTS AND METHODS: Ten patients with an average age of 57 years presented with P. acnes postsurgical shoulder infection. Clinical infection signs and surgical history were assessed and joint aspirates and tissue biopsy specimens were obtained. Diagnosis was confirmed by microbiologic cultures. RESULTS: At the time of confirmation of the diagnosis, clinical signs of infection were absent. C-reactive protein and erythrocyte sedimentation rates were inconsistently elevated. Cultures took a mean 7 days to confirm organism growth. The average time from surgery to diagnosis of infection was 1.8 years (range, 0.07-8.0 years). All patients underwent irrigation and débridement and were treated with antibiotics for 6 weeks. CONCLUSIONS: P. acnes shoulder infections should be considered as a cause for persistent, unexplained shoulder pain. Shoulder aspirations and tissue samples should be obtained. Surgical débridement and intravenous antibiotics are necessary treatment modalities. LEVEL OF EVIDENCE: Level IV, Prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Outpatient healthcare personnel knowledge and attitudes towards infection prevention measures for protection from respiratory infections.

BACKGROUND: Healthcare personnel (HCP) knowledge and attitudes toward infection control measures are important determinants of practices that can protect them from transmission of infectious diseases. METHODS: Healthcare personnel were recruited from Emergency Departments and outpatient clinics at seven sites. They completed knowledge surveys at the beginning and attitude surveys at the beginning and end of each season of participation. Attitudes toward infection prevention and control measures, especially medical masks and N95 respirators, were compared. The proportion of participants who correctly identified all components of an infection control bundle for seven clinical scenarios was calculated. RESULTS: The proportion of participants in the medical mask group who reported at least one reason to avoid using medical masks fell from 88.5% on the pre-season survey to 39.6% on the post-season survey (odds ratio [OR] for preseason vs. postseason 0.11, 95% CI 0.10-0.14). Among those wearing N95 respirators, the proportion fell from 87.9% to 53.6% (OR 0.24, 95% CI 0.21-0.28). Participants correctly identified all components of the infection control bundle for 4.9% to 38.5% of scenarios. CONCLUSIONS: Attitudes toward medical masks and N95 respirators improved significantly between the beginning and end of each season. The proportion of HCP who correctly identified the infection control precautions needed for clinical scenarios was low, but it improved over successive years of participation in the study.

Take-home kits to detect respiratory viruses among healthcare personnel: Lessons learned from a cluster randomized clinical trial.

BACKGROUND: Health care personnel (HCP) working in outpatient settings routinely interact with patients with acute respiratory illnesses. Absenteeism following symptom development and lack of staff trained to obtain samples limit efforts to identify pathogens among infected HCP. METHODS: The Respiratory Protection Effectiveness Clinical Trial assessed respiratory infection incidence among HCP between 2011 and 2015. Research assistants obtained anterior nasal and oropharyngeal swabs from HCP in the workplace following development of respiratory illness symptoms and randomly while asymptomatic. Participants received take-home kits to self-collect swabs when absent from work. Samples mailed to a central laboratory were tested for respiratory viruses by reverse transcription polymerase chain reaction. RESULTS: Among 2,862 participants, 3,467 swabs were obtained from symptomatic participants. Among symptomatic HCP, respiratory virus was detected in 904 of 3,467 (26.1%) samples. Self-collected samples by symptomatic HCP at home had higher rates of viral detection (40.3%) compared to 24% obtained by trained research assistants in the workplace (P < .001). CONCLUSIONS: In this randomized clinical trial, take-home kits were an easily implemented, effective method to self-collect samples by HCP. Other studies have previously shown relative equivalence of self-collected samples to those obtained by trained healthcare workers. Take-home kit self-collection could diminish workforce exposures and decrease the demand for personnel protective equipment worn to protect workers who collect respiratory samples.

Skin and soft-tissue infections requiring hospitalization at an academic medical center: opportunities for antimicrobial stewardship.

BACKGROUND: Although complicated skin and soft-tissue infections (SSTIs) are among the most common infections requiring hospitalization, their clinical spectrum, management, and outcomes have not been well described. METHODS: We report a cohort of consecutive adult patients hospitalized for SSTI from 1 January through 31 December 2007 at an academic medical center. Cases meeting inclusion criteria were reviewed and classified as cellulitis, cutaneous abscess, or SSTI with additional complicating factors. RESULTS: In total, 322 patients were included; 66 (20%) had cellulitis, 103 (32%) had cutaneous abscess, and 153 (48%) had SSTI with additional complicating factors. Injection drug use, diabetes mellitus, and alcohol abuse were common comorbidities. Serum inflammatory markers were routinely measured and blood cultures and imaging studies were routinely performed in each group. Of 150 patients with a positive culture result for an abscess, deep tissue, or blood, Staphylococcus aureus or streptococci were identified in 145 (97%). Use of antibiotics with broad aerobic gram-negative activity (61%-80% of patients) or anaerobic activity (73%-83% of patients) was frequent in each group. The median duration of therapy for cellulitis, cutaneous abscess, and SSTI with additional complicating factors was 13 (interquartile range [IQR], 10-14), 13 (IQR, 10-16), and 14 (IQR, 11-17) days, respectively. Treatment failure, recurrence, or rehospitalization due to SSTI within 30 days occurred in 12.1%, 4.9%, and 9.2% of patients, respectively. CONCLUSIONS: Hospitalizations for SSTI were common; more than half were due to cellulitis or cutaneous abscess. Frequent use of potentially unnecessary diagnostic studies, broad-spectrum antibiotic therapy, and prolonged treatment courses in these patients suggest targets for antimicrobial stewardship programs.

Patterns of early and late ventilator-associated pneumonia due to methicillin-resistant Staphylococcus aureus in a trauma population.

BACKGROUND: Community-acquired methicillin-resistant Staphylococcal aureus (CA-MRSA) infection is approaching endemic proportions nationally, and it is a potential cause for early ventilator-associated pneumonia (VAP) in the acutely injured patient. We sought to determine the prevalence of early (≤4 days) and late (>4 days) MRSA pneumonia in ventilated multisystem trauma patients and to correlate findings with admission nasal swabs. METHODS: We performed a review of our prospective trauma and infectious disease data bases for all patients admitted to our surgical intensive care unit with early (≤4 days) and late (>4 days) VAP during a 4-year period. The diagnosis of pneumonia was established by clinical pulmonary infection score >6, bronchoalveolar lavage, and quantitative cultures showing >10 organisms. Nasal swabs for early identification of MRSA carriers were performed routinely at admission. RESULTS: One hundred seventy-six patients were identified with S. aureus VAP. Patients with MRSA were compared with those with methicillin-susceptible S. aureus (MSSA). There were 47 (27%) early MSSA VAP and only 4 (2.2%) with early MRSA VAP. One hundred twenty-five patients were diagnosed with late VAP. Forty patients (23%) had MRSA VAP and 85 patients (64%) had MSSA VAP. None of the four patients with an early MRSA VAP had positive nasal swabs at admission. CONCLUSION: Despite an increase of MRSA nationally, we found a low incidence of early and late MRSA VAP in trauma patients, which was not identified by nasal swab screening. On the basis of our results, we question the efficacy of empiric vancomycin therapy in early (≤4 days) S. aureus VAP. Furthermore, nasal swabs were not helpful in identifying patients at risk for MRSA VAP.

Antimicrobial resistance patterns in urinary E. coli isolates after a change in a single center's guidelines for uncomplicated cystitis in ambulatory settings.

Recommending nitrofurantoin to treat uncomplicated cystitis was associated with increased nitrofurantoin use from 3.53 to 4.01 prescriptions per 1,000 outpatient visits, but nitrofurantoin resistance in E. coli isolates remained stable at 2%. Concomitant levofloxacin resistance was a significant risk for nitrofurantoin resistance in E. coli isolates (odds ratio [OR], 2.72; 95% confidence interval [CI], 1.04-7.17).

The Special Pathogens Research Network: Enabling Research Readiness.

The 2013-2016 epidemic of Ebola virus disease (EVD) that originated in West Africa underscored many of the challenges to conducting clinical research during an ongoing infectious disease epidemic, both in the most affected countries of Guinea, Liberia, and Sierra Leone, as well as in the United States and Europe, where a total of 27 patients with EVD received care in biocontainment units. The Special Pathogens Research Network (SPRN) was established in the United States in November 2016 to provide an organizational structure to leverage the expertise of the 10 Regional Ebola and Other Special Pathogen Treatment Centers (RESPTCs); it was intended to develop and support infrastructure to improve readiness to conduct clinical research in the United States. The network enables the rapid activation and coordination of clinical research in the event of an epidemic and facilitates opportunities for multicenter research when the RESPTCs are actively caring for patients requiring a biocontainment unit. Here we provide an overview of opportunities identified in the clinical research infrastructure during the West Africa EVD epidemic and the SPRN activities to meet the ongoing challenges in the context of Ebola virus and other special pathogens.

Impact of routine infectious diseases service consultation on the evaluation, management, and outcomes of Staphylococcus aureus bacteremia.

BACKGROUND: Staphylococcus aureus bacteremia causes considerable morbidity and mortality, and strategies to improve management and outcomes of this disease are needed. METHODS: Routine consultation with an infectious diseases specialist for cases of S. aureus bacteremia was mandated at our institution in May 2005. We compared the evaluation, management, and outcomes of cases before and after this policy change. All comparisons are by period (i.e., before or after initiation of the policy of routine consultation). RESULTS: In the year before and the year after after the implementation of routine consultation, 134 and 100 cases of S. aureus bacteremia, respectively, were evaluated. Consultation rates increased from 53% of cases before to 90% of cases after the policy change (p < .001). Echocardiography (57% vs. 73%; p = .01) and radiographic studies (81% vs. 91%; p = .04) were used more frequently during the period of routine consultation, and infective endocarditis or metastatic infections were diagnosed more frequently (33% vs. 46%; p = .04). All 4 standards of care (removal of intravascular foci of infection, obtaining follow-up blood culture samples, use of parenteral beta-lactam therapy when possible, and administration of >/=28 days of therapy for complicated infections) were adhered to more frequently with routine consultation (40% vs. 74%; P <.001). Treatment failure (microbiological failure, recurrent bacteremia, late metastatic infection, or death) occurred less often during the intervention year (17% vs. 12%), but this difference was not statistically significant (p = .27). CONCLUSIONS: A policy of routine consultation with an infectious diseases specialist for patients with S. aureus bacteremia resulted in more-detailed evaluation, more-frequent detection of endocarditis and metastatic infection, and improved adherence to standards of care.

Community-acquired methicillin-resistant Staphylococcus aureus emerging as an important cause of necrotizing fasciitis.

BACKGROUND: Necrotizing fasciitis (NF) is an uncommon fulminant soft tissue infection characterized by extensive fascial necrosis. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) isolates producing the Panton-Valentine leukocidin (PVL) cytotoxin have been associated with serious necrotizing infections, but NF caused by CA-MRSA has been described only recently. We reviewed our NF experience at Denver Health Medical Center, where CA-MRSA accounts for more than 50% of community S. aureus clinical isolates. METHODS: Patients treated for NF from January 2004 to February 2006 were identified by review of pathology records and diagnostic codes, and their medical records were reviewed. Isolates of MRSA from monomicrobial NF underwent testing for the PVL gene and pulsed-field gel electrophoresis to determine relatedness to CA-MRSA strains. RESULTS: Five of 30 NF cases during the study period, all involving the extremities, were caused by MRSA. Monomicrobial MRSA NF accounted for three cases, with all of the patients reporting a distinct "spider bite" lesion 2-3 days prior to admission. The median age was 32 years (range 28-55 years). Resistance to erythromycin and levofloxacin was present in four isolates. None of the isolates displayed inducible clindamycin resistance. Within 12 hours of admission, all patients received empiric antibiotics to which their isolate was susceptible. Patients required a median of six surgical procedures (range 2-7 operations). All patients survived. The MRSA isolates tested positive for PVL and had the USA 300 CA-MRSA deoxyribonucleic acid banding pattern. CONCLUSIONS: Community-acquired MRSA is an important cause of NF in our region, accounting for > 15% of NF cases. This infection was associated with significant morbidity necessitating multiple surgical interventions. Given the propensity of PVL-positive CA-MRSA to cause severe necrotizing infections, it is reasonable to administer empiric MRSA coverage for NF in endemic locations.

Protecting Healthcare Personnel in Outpatient Settings: The Influence of Mandatory Versus Nonmandatory Influenza Vaccination Policies on Workplace Absenteeism During Multiple Respiratory Virus Seasons.

OBJECTIVE To determine the effect of mandatory and nonmandatory influenza vaccination policies on vaccination rates and symptomatic absenteeism among healthcare personnel (HCP). DESIGN Retrospective observational cohort study. SETTING This study took place at 3 university medical centers with mandatory influenza vaccination policies and 4 Veterans Affairs (VA) healthcare systems with nonmandatory influenza vaccination policies. PARTICIPANTS The study included 2,304 outpatient HCP at mandatory vaccination sites and 1,759 outpatient HCP at nonmandatory vaccination sites. METHODS To determine the incidence and duration of absenteeism in outpatient settings, HCP participating in the Respiratory Protection Effectiveness Clinical Trial at both mandatory and nonmandatory vaccination sites over 3 viral respiratory illness (VRI) seasons (2012-2015) reported their influenza vaccination status and symptomatic days absent from work weekly throughout a 12-week period during the peak VRI season each year. The adjusted effects of vaccination and other modulating factors on absenteeism rates were estimated using multivariable regression models. RESULTS The proportion of participants who received influenza vaccination was lower each year at nonmandatory than at mandatory vaccination sites (odds ratio [OR], 0.09; 95% confidence interval [CI], 0.07-0.11). Among HCP who reported at least 1 sick day, vaccinated HCP had lower symptomatic days absent compared to unvaccinated HCP (OR for 2012-2013 and 2013-2014, 0.82; 95% CI, 0.72-0.93; OR for 2014-2015, 0.81; 95% CI, 0.69-0.95). CONCLUSIONS These data suggest that mandatory HCP influenza vaccination policies increase influenza vaccination rates and that HCP symptomatic absenteeism diminishes as rates of influenza vaccination increase. These findings should be considered in formulating HCP influenza vaccination policies. Infect Control Hosp Epidemiol 2018;39:452-461.

Epidemiologic, clinical, and economic evaluation of an outbreak of clonal multidrug-resistant Acinetobacter baumannii infection in a surgical intensive care unit.

OBJECTIVES: To determine risk factors for acquisition of multidrug-resistant (MDR) Acinetobacter baumannii infection during an outbreak, to describe the clinical manifestations of infection, and to ascertain the cost of infection. DESIGN: Case-control study. SETTING: Surgical intensive care unit in a 400-bed urban teaching hospital and level 1 trauma center. PATIENTS: Case patients received a diagnosis of infection due to A. baumannii isolates with a unique pattern of drug resistance (ie, susceptible to imipenem, variably susceptible to aminoglycosides, and resistant to all other antibiotics) between December 1, 2004, and August 31, 2005. Case patients were matched 1 : 1 with concurrently hospitalized control patients. Isolates' genetic relatedness was established by pulsed-field gel electrophoresis. RESULTS: Sixty-seven patients met the inclusion criteria. Case and control patients were similar with respect to age, duration of hospitalization, and Charlson comorbidity score. MDR A. baumannii infections included ventilator-associated pneumonia (in 56.7% of patients), bacteremia (in 25.4%), postoperative wound infections (in 25.4%), central venous catheter-associated infections (in 20.9%), and urinary tract infections (in 10.4%). Conditional multiple logistic regression was used to determine statistically significant risk factors on the basis of results from the bivariate analyses. The duration of hospitalization and healthcare charges were modeled by multiple linear regression. Significant risk factors included higher Acute Physiology and Chronic Health Evaluation II score (odds ratio [OR], 1.1 per point increase; P=.06), duration of intubation (OR, 1.4 per day intubated; P<.01), exposure to bronchoscopy (OR, 22.7; P=.03), presence of chronic pulmonary disease (OR, 77.7; P=.02), receipt of fluconazole (OR, 73.3; P<.01), and receipt of levofloxacin (OR, 11.5; P=.02). Case patients had a mean of $60,913 in attributable excess patient charges and a mean of 13 excess hospital days. INTERVENTIONS: Infection control measures included the following: limitations on the performance of pulsatile lavage wound debridement, the removal of items with upholstered surfaces, and the implementation of contact isolation for patients with suspected MDR A. baumannii infection. CONCLUSIONS: This large outbreak of infection due to clonal MDR A. baumannii caused significant morbidity and expense. Aerosolization of MDR A. baumannii during pulsatile lavage debridement of infected wounds and during the management of respiratory secretions from colonized and infected patients may promote widespread environmental contamination. Multifaceted infection control interventions were associated with a decrease in the number of MDR A. baumannii isolates recovered from patients.

Evidence of nosocomial transmission of human rhinovirus in a neonatal intensive care unit.

Nosocomial respiratory infections cause significant morbidity and mortality, especially among the extremely susceptible neonatal population. Human rhinovirus C is a common viral respiratory illness that causes significant complications in children <2 years old. We describe a nosocomial outbreak of human rhinovirus C in a level II-III neonatal intensive care unit in an urban public safety net hospital.

Clinical Reasoning of Infectious Diseases Physicians Behind the Use or Nonuse of Transesophageal Echocardiography in Staphylococcus aureus Bacteremia.

In this prospective cohort with Staphylococcus aureus bacteremia, transesophageal echocardiography (TEE) was performed in 24% of cases. Consulting Infectious Diseases physicians most frequently cited low suspicion for endocarditis due to rapid clearance of blood cultures and the presence of a secondary focus requiring an extended treatment duration as reasons for foregoing TEE.