Eugene V. Millar

Invasive mold infections following combat-related injuries.

BACKGROUNDnMajor advances in combat casualty care have led to increased survival of patients with complex extremity trauma. Invasive fungal wound infections (IFIs) are an uncommon, but increasingly recognized, complication following trauma that require greater understanding of risk factors and clinical findings to reduce morbidity.nnnMETHODSnThe patient population includes US military personnel injured during combat from June 2009 through December 2010. Case definition required wound necrosis on successive debridements with IFI evidence by histopathology and/or microbiology (Candida spp excluded). Case finding and data collected through the Trauma Infectious Disease Outcomes Study utilized trauma registry, hospital records or operative reports, and pathologist review of histopathology specimens.nnnRESULTSnA total of 37 cases were identified: proven (angioinvasion, n=20), probable (nonvascular tissue invasion, n=4), and possible (positive fungal culture without histopathological evidence, n=13). In the last quarter surveyed, rates reached 3.5% of trauma admissions. Common findings include blast injury (100%) during foot patrol (92%) occurring in southern Afghanistan (94%) with lower extremity amputation (80%) and large volume blood transfusion (97.2%). Mold isolates were recovered in 83% of cases (order Mucorales, n=16; Aspergillus spp, n=16; Fusarium spp, n=9), commonly with multiple mold species among infected wounds (28%). Clinical outcomes included 3 related deaths (8.1%), frequent debridements (median, 11 cases), and amputation revisions (58%).nnnCONCLUSIONSnIFIs are an emerging trauma-related infection leading to significant morbidity. Early identification, using common characteristics of patient injury profile and tissue-based diagnosis, should be accompanied by aggressive surgical and antifungal therapy (liposomal amphotericin B and a broad-spectrum triazole pending mycology results) among patients with suspicious wounds.

Development of the Flu-PRO: a patient-reported outcome (PRO) instrument to evaluate symptoms of influenza

BackgroundTo develop content validity of a comprehensive patient-reported outcome (PRO) measure following current best scientific methodology to standardize assessment of influenza (flu) symptoms in clinical research.MethodsStage I (Concept Elicitation): 1:1 telephone interviews with influenza-positive adults (≥18xa0years) in the US and Mexico within 7xa0days of diagnosis. Participants described symptom type, character, severity, and duration. Content analysis identified themes and developed the draft Flu-PRO instrument. Stage II (Cognitive Interviewing): The Flu-PRO was administered to a unique set of influenza-positive adults within 14xa0days of diagnosis; telephone interviews addressed completeness, respondent interpretation of items and ease of use.ResultsSamples: Stage I: Nu2009=u200946 adults (16 US, 30 Mexico); mean (SD) age: 38 (19), 39 (14) years; % female: 56xa0%, 73xa0%; race: 69xa0% White, 97xa0% Mestizo. Stage II: Nu2009=u200934 adults (12 US, 22 Mexico); age: 37 (14), 39 (11) years; % female: 50xa0%, 50xa0%; race: 58xa0% White, 100xa0% Mestizo. Symptoms: Symptoms identified by >50xa0%: coughing, weak or tired, throat symptoms, congestion, headache, weakness, sweating, chills, general discomfort, runny nose, chest (trouble breathing), difficulty sleeping, and body aches or pains. No new content was uncovered during Stage II; participants easily understood the instrument.ConclusionsResults show the 37-item Flu-PRO is a content valid measure of influenza symptoms in adults with a confirmed diagnosis of influenza. Research is underway to evaluate the suitability of the instrument for children and adolescents. This work can form the basis for future quantitative tests of reliability, validity, and responsiveness to evaluate the measurement properties of Flu-PRO for use in clinical trials and epidemiology studies.

Impact of More Than a Decade of Pneumococcal Conjugate Vaccine Use on Carriage and Invasive Potential in Native American Communities

BACKGROUNDnWe assessed the impact of 12 years of pneumococcal conjugate vaccine (PCV7) use on pneumococcal nasopharyngeal carriage and serotype-specific invasive disease potential among Native Americans.nnnMETHODSnFamilies were enrolled in a carriage study from 2006 to 2008; nasopharyngeal specimens and risk factor information were collected monthly for 7 visits. Pneumococcal carriage prevalence was compared with that before (1998-2000) and during (2001-2002) PCV7 introduction. We compared invasive disease incidence and carriage prevalence before and after PCV7 introduction to estimate changes in serotype-specific invasive potential.nnnRESULTSnWe enrolled 1077 subjects from 302 households. There was an absolute reduction in carriage prevalence of 8.0% (95% confidence interval [CI], 4.5%-11.4%) in children aged <5 years and 3.1% (95% CI, 1.1%-5.1%) in adults. In children aged <5 years, vaccine-serotype carriage prevalence decreased by 22.8% (95% CI, 20.1%-25.3%), and nonvaccine serotype (NVT) increased by 15.9% (95% CI, 12.4%-19.3%). No significant change was detected in serotype-specific invasive potential after PCV7 introduction.nnnCONCLUSIONSnPneumococcal carriage prevalence decreased in all ages since PCV7 introduction; vaccine-serotype carriage has been nearly eliminated, whereas the prevalence of NVT carriage has increased. The increase in the NVT invasive disease rate seems to be proportional to the increase in colonization prevalence.

Infection-associated clinical outcomes in hospitalized medical evacuees after traumatic injury: trauma infectious disease outcome study.

Infections have long been known to complicate care in patients following traumatic injury frequently leading to excess morbidity and mortality.1, 2 In no setting is this more well-recognized than the challenging environment of combat casualty care. During the current military conflicts in Iraq and Afghanistan, Operations Iraqi and Enduring Freedom (OIF/OEF), major advances resulting in increased survival among wounded personnel have been observed. These include enhanced training of medics, forward deployment of surgical assets, rapid medical evacuation, and improvements in body armor.3–5 The significant advances leading to survival are coupled with major challenges in care due to the extensive nature of the injuries, profound bone and soft tissue disruption, and extensive wound contamination.6, 7 In addition, the rapid transit of these patients through multiple echelons of medical care places significant obstacles on infection control in an era of increasing risk due to hospital-associated multidrug resistant (MDRO) organisms.8, 9 n nThe U.S. Department of Defense (DoD) has implemented a range of measures to improve combat casualty care and mitigate risk of infectious complications. A Joint Theater Trauma System and Joint Theater Trauma Registry (JTTR) have been developed to benchmark metrics and to provide a timely assessment of performance improvement interventions.5, 10, 11 Efforts to prevent infection include the development of guidelines for the prevention of infection related to combat injuries through comprehensive review of current evidence and consensus review by military and civilian experts in trauma, infectious disease, infection control, preventive medicine, and surgical specialties.12 In addition, standardized infection control measures across echelons of care accompanied by enhanced MDRO surveillance and serial evaluation have also been implemented.13, 14 n nDespite the growing literature describing infectious complications of combat-related trauma, there is still a lack of prospectively collected standardized infection data that includes specific therapy, microbiological findings and clinical outcomes across treatment facilities. This report describes the initial data and current status of an ongoing 5-year prospective observational cohort study of infectious complications associated with traumatic injury sustained during deployment, the DoD-Department of Veterans Affairs (VA) Trauma Infectious Disease Outcomes Study (TIDOS).

Durability of antibody responses after receipt of the monovalent 2009 pandemic influenza A (H1N1) vaccine among HIV-infected and HIV-uninfected adults.

BACKGROUNDnHuman immunodeficiency virus (HIV)-infected persons are at risk for severe influenza infections. Although vaccination against the H1N1 pandemic influenza strain is recommended, currently there are no data on the durability of post-vaccination antibody responses in this population.nnnMETHODSnHIV-infected and HIV-uninfected adults (18-50 years old) received a single dose of monovalent 2009 influenza A (H1N1) vaccine (strain A/California/7/2009H1N1). Antibody levels to the 2009 H1N1 pandemic strain were determined at day 0, day 28, and 6 months by hemagglutination-inhibition assay. A seroprotective response was a post-vaccination titer of ≥1:40 among those with a pre-vaccination level of ≤1:10. Geometric mean titers (GMT) and factors associated with higher levels were also evaluated.nnnRESULTSnWe studied 127 participants with a median age of 35 (interquartile range (IQR) 28, 42) years. Among the HIV-infected arm (n=63), the median CD4 count was 595 (IQR 476, 819)cells/mm(3) and 83% were receiving HAART. Thirty-five percent of all participants had a pre-vaccination level of >1:10. HIV-infected compared to HIV-uninfected adults were less likely to generate a seroprotective response at day 28 (54% vs. 75%, adjusted OR 0.23, p=0.021) or have a durable response at 6 months post-vaccination (28% vs. 56%, adjusted OR 0.19, p=0.005). Additionally, although pre-vaccination GMT were similar in both arms (median 7 vs. 8, p=0.11), the GMT at 6 months was significantly lower among HIV-infected versus HIV-uninfected adults (median 20 vs. 113, p=0.003). Among HIV-infected persons, younger age (p=0.035) and receipt of HAART (p=0.028) were associated with higher GMTs at 6 months.nnnCONCLUSIONSnDespite vaccination, most HIV-infected adults do not generate durable seroprotective antibody responses to the 2009 influenza A (H1N1) virus, and hence may remain vulnerable to infection. In addition to HAART use, more immunogenic vaccines are likely needed for improving protection against influenza in this population.

Hygiene strategies to prevent methicillin-resistant Staphylococcus aureus skin and soft-tissue infections: a cluster-randomized controlled trial among high-risk military trainees

BACKGROUNDnEffective measures are needed to prevent methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infections (SSTIs) in high-risk community settings. The study objective was to evaluate the effect of personal hygiene-based strategies on rates of overall SSTI and MRSA SSTI.nnnMETHODSnWe conducted a prospective, field-based, cluster-randomized trial in US Army Infantry trainees from May 2010 through January 2012. There were 3 study groups with incrementally increased education and hygiene-based interventions: standard (S), enhanced standard (ES), and chlorhexidine (CHG). The primary endpoints were incidence of overall SSTI and MRSA SSTI.nnnRESULTSnThe study included 30 209 trainees constituting 540 platoons (168 S, 192 ES, and 180 CHG). A total of 1203 (4%) participants developed SSTI, 316 (26%) due to MRSA. The overall SSTI rate was 4.15 (95% confidence interval [CI], 3.77-4.58) per 100 person-cycles. SSTI rates by study group were 3.48 (95% CI, 2.87-4.22) for S, 4.18 (95% CI, 3.56-4.90) for ES, and 4.71 (95% CI, 4.03-5.50) for CHG. The MRSA SSTI rate per 100 person-cycles for all groups was 1.10 (95% CI, .91-1.32). MRSA SSTI rates by study group were 1.0 (95% CI, .70-1.42) for S, 1.29 (95% CI, .98-1.71) for ES, and 0.97 (95% CI, .70-1.36) for CHG.nnnCONCLUSIONSnPersonal hygiene and education measures, including once-weekly use of chlorhexidine body wash, did not prevent overall SSTI or MRSA SSTI in a high-risk population of military trainees.nnnCLINICAL TRIALS REGISTRATIONnNCT01105767.

Prevalence of Chlorhexidine-Resistant Methicillin-Resistant Staphylococcus aureus following Prolonged Exposure

ABSTRACT Chlorhexidine has been increasingly utilized in outpatient settings to control methicillin-resistant Staphylococcus aureus (MRSA) outbreaks and as a component of programs for MRSA decolonization and prevention of skin and soft-tissue infections (SSTIs). The objective of this study was to determine the prevalence of chlorhexidine resistance in clinical and colonizing MRSA isolates obtained in the context of a community-based cluster-randomized controlled trial for SSTI prevention, during which 10,030 soldiers were issued chlorhexidine for body washing. We obtained epidemiological data on study participants and performed molecular analysis of MRSA isolates, including PCR assays for determinants of chlorhexidine resistance and high-level mupirocin resistance and pulsed-field gel electrophoresis (PFGE). During the study period, May 2010 to January 2012, we identified 720 MRSA isolates, of which 615 (85.4%) were available for molecular analysis, i.e., 341 clinical and 274 colonizing isolates. Overall, only 10 (1.6%) of 615 isolates were chlorhexidine resistant, including three from the chlorhexidine group and seven from nonchlorhexidine groups (P > 0.99). Five (1.5%) of the 341 clinical isolates and five (1.8%) of the 274 colonizing isolates harbored chlorhexidine resistance genes, and four (40%) of the 10 possessed genetic determinants for mupirocin resistance. All chlorhexidine-resistant isolates were USA300. The overall prevalence of chlorhexidine resistance in MRSA isolates obtained from our study participants was low. We found no association between extended chlorhexidine use and the prevalence of chlorhexidine-resistant MRSA isolates; however, continued surveillance is warranted, as this agent continues to be utilized for infection control and prevention efforts.

Epidemiologic, clinical, and virologic characteristics of human rhinovirus infection among otherwise healthy children and adults: Rhinovirus among adults and children

n Abstractn n Backgroundn human rhinovirus (HRV) is a major cause of influenza-like illness (ILI) in adults and children. Differences in disease severity by HRV species have been described among hospitalized patients with underlying illness. Less is known about the clinical and virologic characteristics of HRV infection among otherwise healthy populations, particularly adults.n n n Objectivesn to characterize molecular epidemiology of HRV and association between HRV species and clinical presentation and viral shedding.n n n Study designn observational, prospective, facility-based study of ILI was conducted from February 2010 to April 2012. Collection of nasopharyngeal specimens, patient symptoms, and clinical information occurred on days 0, 3, 7, and 28. Patients recorded symptom severity daily for the first 7 days of illness in a symptom diary. HRV was identified by RT-PCR and genotyped for species determination. Cases who were co-infected with other viral respiratory pathogens were excluded from the analysis. We evaluated the associations between HRV species, clinical severity, and patterns of viral shedding.n n n Resultsn eighty-four HRV cases were identified and their isolates genotyped. Of these, 62 (74%) were >18 years. Fifty-four were HRV-A, 11HRV-B, and 19HRV-C. HRV-C infection was more common among children than adults (59% vs. 10%, Pn <0.001). Among adults, HRV-A was associated with higher severity of upper respiratory symptoms compared to HRV-B (Pn =0.02), but no such association was found in children. In addition, adults shed HRV-A significantly longer than HRV-C (P trend=0.01).n n n Conclusionsn among otherwise healthy adults with HRV infection, we observed species-specific differences in respiratory symptom severity and duration of viral shedding.n n

Effect of Early Screening for Invasive Fungal Infections in U.S. Service Members with Explosive Blast Injuries

BACKGROUNDnAn outbreak of invasive fungal infections (IFI) began in 2009 among United States servicemen who sustained blast injuries in Afghanistan. In response, the military trauma community sought a uniform approach to early diagnosis and treatment. Toward this goal, a local clinical practice guideline (CPG) was implemented at Landstuhl Regional Medical Center (LRMC) in early 2011 to screen for IFI in high-risk patients using tissue histopathology and fungal cultures.nnnMETHODSnWe compared IFI cases identified after initiation of the CPG (February through August 2011) to cases from a pre-CPG period (June 2009 through January 2011).nnnRESULTSnSixty-one patients were screened in the CPG period, among whom 30 IFI cases were identified and compared with 44 pre-CPG IFI cases. Demographics between the two study periods were similar, although significantly higher transfusion requirements (p<0.05) and non-significant trends in injury severity scores and early lower extremity amputation rates suggested more severe injuries in CPG-period cases. Pre-CPG IFI cases were more likely to be associated with angioinvasion on histopathology than CPG IFI cases (48% versus 17%; p<0.001). Time to IFI diagnosis (three versus nine days) and to initiation of antifungal therapy (seven versus 14 days) were significantly decreased in the CPG period (p<0.001). Additionally, more IFI patients received antifungal agent at LRMC during the CPG period (30%) versus pre-CPG period (5%; p=0.005). The CPG IFI cases were also prescribed more commonly dual antifungal therapy (73% versus 36%; p=0.002). There was no statistical difference in length of stay or mortality between pre-CPG and CPG IFI cases; although a non-significant reduction in crude mortality from 11.4% to 6.7% was observed.nnnCONCLUSIONSnAngioinvasive IFI as a percentage of total IFI cases decreased during the CPG period. Earlier diagnosis and commencement of more timely treatment was achieved. Despite these improvements, no difference in clinical outcomes was observed compared with the pre-CPG period.

Nontypeable Pneumococcal Isolates Among Navajo and White Mountain Apache Communities: Are These Really a Cause of Invasive Disease?

BACKGROUNDnPneumococci could evade pneumococcal conjugate vaccines (PCV) by modifying, mutating, or deleting vaccine-serotype capsule genes or by downregulating capsule production. We sought to assess whether pneumococci that are nontypeable (NT) by the Quellung reaction truly lack capsule genes or are failing to produce capsule in vitro.nnnMETHODSnWe applied multilocus sequence typing and a microarray for detection of pneumococcal polysaccharide capsule biosynthesis genes to NT carriage (children aged <5 years; years 1997-2000, 2006-2008) and NT invasive disease (IPD) (all ages; years 1994-2007) isolates from Native American communities.nnnRESULTSnTwenty-seven of 28 (96.4%) NT IPD isolates had sequence types (STs) typically found among typeable IPD isolates and contained whole or fragments of capsule genes that matched known serotypes; 1 NT-IPD isolate had a profile resembling NT carriage isolates. Forty-nine of 76 (64.5%) NT carriage isolates had STs that typically lack capsule genes and were similar to NT carriage isolates found globally.nnnCONCLUSIONSnThis is the first documentation of IPD from an NT strain confirmed to lack all known capsule genes. Most NT IPD isolates have or had the capacity to produce capsule, whereas a majority of NT carriage isolates lack this capacity. We found no evidence of pneumococcal adaptation to PCV7 via downregulation or deletion of vaccine-serotype capsule genes.