Self-Reported History of Chlamydia or Gonorrhea Testing Among Heterosexual Women at High Risk of HIV Infection, National HIV Behavioral Surveillance, 2013.

BACKGROUND: The US Preventive Services Task Force recommends annual chlamydia and gonorrhea screening for sexually active women <25 and ≥25 years old with associated risk factors. We sought to determine self-reported chlamydia and gonorrhea testing and diagnosis rates in the past 12 months in a community-based sample of heterosexual women at high risk of HIV infection. METHODS: We used National HIV Behavioral Surveillance data from 2013 when surveillance was conducted in heterosexual adults with low social economic status. Our analysis was restricted to 18- to 44-year-old women who answered questions regarding chlamydia/gonorrhea testing and diagnosis in the previous 12 months. We calculated the percentage reporting testing and diagnosis. Poisson regressions with generalized estimating equations clustered on recruitment chain were used to assess factors associated with testing and diagnosis. RESULTS: Among 18- to 24-year-old women (n = 1017), 61.0% self-reported chlamydia testing and 57.6% gonorrhea testing in the past 12 months. Among 25- to 44-year-old women (n = 2322), 49.0% and 47.0% reported chlamydia and gonorrhea testing, respectively. Among the subset of 25- to 44-year-old women who met screening criteria, 51.2% reported chlamydia testing. Having seen a medical provider and HIV testing (past 12 months) were associated with chlamydia/gonorrhea testing in both age groups. Self-reported chlamydia (18-24 years, 21.4%; 25-44 years, 12.2%) and gonorrhea diagnoses (18-24 years, 8.4%; 25-44 years, 6.6%) were common. CONCLUSIONS: A substantial number of eligible women may not have been screened for chlamydia/gonorrhea. Renewed efforts to facilitate screening may prevent sequelae and support disease control activities.

Self-Reported Infertility and Associated Pelvic Inflammatory Disease Among Women of Reproductive Age-National Health and Nutrition Examination Survey, United States, 2013-2016.

BACKGROUND: Sexually transmitted diseases, including chlamydia and gonorrhea, cause of pelvic inflammatory disease (PID) and infertility. We estimated the prevalence of infertility and infertility health care seeking. METHODS: We analyzed self-reported lifetime infertility and infertility health care-seeking in women aged 18 to 49 years in the 2013 and 2015 National Health and Nutrition Examination Surveys. Weighted prevalence of infertility and infertility health care seeking, prevalence ratios (PRs), and 95% confidence intervals (CIs) were calculated. RESULTS: Among 2626 eligible women, 13.8% had self-reported infertility (95% CI, 12.3-15.3) with higher prevalence by age: 960, 18 to 29 years (PR, 6.4%; 95% CI, 4.8-8.0); 799, 30 to 39 years (PR, 14.8%; 95% CI, 12.2-17.3); and 867, 40 to 49 years (PR, 20.8%; 95% CI, 17.2-24.4). Non-Hispanic white women (PR, 15.4%; 95% CI, 13.0-17.8; n = 904) and non-Hispanic black women (PR, 12.9%; 95% CI, 10.3-15.5; n = 575) had the highest infertility prevalences. Women reporting PID treatment (n = 122) had higher infertility prevalence (PR, 24.2%; 95% CI, 16.2-32.2) than women without PID treatment (PR, 13.3%; 95% CI, 11.6-15.0; n = 2,485), especially among 18- to 29-year-old women (PR, 3.8; 95% CI, 1.8-8.0). Of 327 women with infertility, 60.9% (95% CI, 56.1-65.8) sought health care. Women without health care insurance sought care less frequently than women with insurance. CONCLUSIONS: In a nationally representative sample, 13.8% of reproductive-age women reported a history of infertility, of whom 40% did not access health care. Self-reported PID was associated with infertility, especially in young women. Annual chlamydia and gonorrhea screening to avert PID may reduce the burden of infertility in the United States.

Advancing the public health applications of Chlamydia trachomatis serology.

Genital Chlamydia trachomatis infection is the most commonly diagnosed sexually transmitted infection. Trachoma is caused by ocular infection with C trachomatis and is the leading infectious cause of blindness worldwide. New serological assays for C trachomatis could facilitate improved understanding of C trachomatis epidemiology and prevention. C trachomatis serology offers a means of investigating the incidence of chlamydia infection and might be developed as a biomarker of scarring sequelae, such as pelvic inflammatory disease. Therefore, serological assays have potential as epidemiological tools to quantify unmet need, inform service planning, evaluate interventions including screening and treatment, and to assess new vaccine candidates. However, questions about the performance characteristics and interpretation of C trachomatis serological assays remain, which must be addressed to advance development within this field. In this Personal View, we explore the available information about C trachomatis serology and propose several priority actions. These actions involve development of target product profiles to guide assay selection and assessment across multiple applications and populations, establishment of a serum bank to facilitate assay development and evaluation, and development of technical and statistical methods for assay evaluation and analysis of serological findings. The field of C trachomatis serology will benefit from collaboration across the public health community to align technological developments with their potential applications.

Performance of Chlamydia trachomatis OmcB Enzyme-Linked Immunosorbent Assay in Serodiagnosis of Chlamydia trachomatis Infection in Women.

Chlamydia trachomatis serological assays with improved sensitivity over commercially available assays are needed to evaluate the burden of C. trachomatis infection and the effectiveness of prevention efforts. We evaluated the performance of a C. trachomatis outer membrane complex protein B (OmcB) enzyme-linked immunosorbent assay (ELISA) in the detection of anti-C. trachomatis antibody responses in C. trachomatis-infected women. OmcB ELISA was less sensitive than our C. trachomatis elementary body (EB) ELISA, but it was highly specific. The magnitude of the antibody response was higher in African-Americans and those with prior C. trachomatis infection. Unlike EB ELISA, the IgG1 response to C. trachomatis OmcB was short-lived and was not maintained by repeat C. trachomatis infection.

Population-attributable fraction of tubal factor infertility associated with chlamydia.

BACKGROUND: Chlamydia trachomatis infection is highly prevalent among young women in the United States. Prevention of long-term sequelae of infection, including tubal factor infertility, is a primary goal of chlamydia screening and treatment activities. However, the population-attributable fraction of tubal factor infertility associated with chlamydia is unclear, and optimal measures for assessing tubal factor infertility and prior chlamydia in epidemiological studies have not been established. Black women have increased rates of chlamydia and tubal factor infertility compared with White women but have been underrepresented in prior studies of the association of chlamydia and tubal factor infertility. OBJECTIVES: The objectives of the study were to estimate the population-attributable fraction of tubal factor infertility associated with Chlamydia trachomatis infection by race (Black, non-Black) and assess how different definitions of Chlamydia trachomatis seropositivity and tubal factor infertility affect population-attributable fraction estimates. STUDY DESIGN: We conducted a case-control study, enrolling infertile women attending infertility practices in Birmingham, AL, and Pittsburgh, PA, during October 2012 through June 2015. Tubal factor infertility case status was primarily defined by unilateral or bilateral fallopian tube occlusion (cases) or bilateral fallopian tube patency (controls) on hysterosalpingogram. Alternate tubal factor infertility definitions incorporated history suggestive of tubal damage or were based on laparoscopic evidence of tubal damage. We aimed to enroll all eligible women, with an expected ratio of 1 and 3 controls per case for Black and non-Black women, respectively. We assessed Chlamydia trachomatis seropositivity with a commercial assay and a more sensitive research assay; our primary measure of seropositivity was defined as positivity on either assay. We estimated Chlamydia trachomatis seropositivity and calculated Chlamydia trachomatis-tubal factor infertility odds ratios and population-attributable fraction, stratified by race. RESULTS: We enrolled 107 Black women (47 cases, 60 controls) and 620 non-Black women (140 cases, 480 controls). Chlamydia trachomatis seropositivity by either assay was 81% (95% confidence interval, 73-89%) among Black and 31% (95% confidence interval, 28-35%) among non-Black participants (P < .001). Using the primary Chlamydia trachomatis seropositivity and tubal factor infertility definitions, no significant association was detected between chlamydia and tubal factor infertility among Blacks (odds ratio, 1.22, 95% confidence interval, 0.45-3.28) or non-Blacks (odds ratio, 1.41, 95% confidence interval, 0.95-2.09), and the estimated population-attributable fraction was 15% (95% confidence interval, -97% to 68%) among Blacks and 11% (95% confidence interval, -3% to 23%) among non-Blacks. Use of alternate serological measures and tubal factor infertility definitions had an impact on the magnitude of the chlamydia-tubal factor infertility association and resulted in a significant association among non-Blacks. CONCLUSION: Low population-attributable fraction estimates suggest factors in addition to chlamydia contribute to tubal factor infertility in the study population. However, high background Chlamydia trachomatis seropositivity among controls, most striking among Black participants, could have obscured an association with tubal factor infertility and resulted in a population-attributable fraction that underestimates the true etiological role of chlamydia. Choice of chlamydia and tubal factor infertility definitions also has an impact on the odds ratio and population-attributable fraction estimates.

Immunoglobulin-Based Investigation of Spontaneous Resolution of Chlamydia trachomatis Infection.

Chlamydia trachomatis elementary body enzyme-linked immunosorbent assay (ELISA) was used to investigate serum anti-CT immunoglobulin G1 (IgG1; long-lived response) and immunoglobulin G3 (IgG3; short-lived response indicating more recent infection) from treatment (enrollment) and 6-month follow-up visits in 77 women previously classified as having spontaneous resolution of chlamydia. Of these women, 71.4% were IgG1+IgG3+, consistent with more recent chlamydia resolution. 15.6% were IgG3- at both visits, suggesting absence of recent chlamydia. Using elementary body ELISA, we demonstrated approximately 1 in 6 women classified as having spontaneous resolution of chlamydia might have been exposed to C. trachomatis but not infected. Further, we classified their possible infection stage.

The Use of Mathematical Models of Chlamydia Transmission to Address Public Health Policy Questions: A Systematic Review.

BACKGROUND: Mathematical models of chlamydia transmission can help inform disease control policy decisions when direct empirical evaluation of alternatives is impractical. We reviewed published chlamydia models to understand the range of approaches used for policy analyses and how the studies have responded to developments in the field. METHODS: We performed a literature review by searching Medline and Google Scholar (up to October 2015) to identify publications describing dynamic chlamydia transmission models used to address public health policy questions. We extracted information on modeling methodology, interventions, and key findings. RESULTS: We identified 47 publications (including two model comparison studies), which reported collectively on 29 distinct mathematical models. Nine models were individual-based, and 20 were deterministic compartmental models. The earliest studies evaluated the benefits of national-level screening programs and predicted potentially large benefits from increased screening. Subsequent trials and further modeling analyses suggested the impact might have been overestimated. Partner notification has been increasingly evaluated in mathematical modeling, whereas behavioral interventions have received relatively limited attention. CONCLUSIONS: Our review provides an overview of chlamydia transmission models and gives a perspective on how mathematical modeling has responded to increasing empirical evidence and addressed policy questions related to prevention of chlamydia infection and sequelae.

Prevalence of Pelvic Inflammatory Disease in Sexually Experienced Women of Reproductive Age - United States, 2013-2014.

Pelvic inflammatory disease (PID) is a clinical syndrome of the female reproductive tract characterized by inflammation of the endometrium, fallopian tubes, or peritoneum (1). PID occurs when microorganisms ascend from the vagina or cervix to the fallopian tubes and other upper genital tract structures (1). PID can result from untreated bacterial infections, including chlamydia and gonorrhea, and can lead to infertility, ectopic pregnancy, and chronic pelvic pain (1). Because there is no single diagnostic test for PID, clinicians rely on nonspecific signs and symptoms for diagnosis. The purpose of these analyses was to assess the burden of self-reported PID in a nationally representative sample using data from the National Health and Nutrition Examination Survey (NHANES) 2013-2014 cycle. Starting in 2013, NHANES female participants aged 18-44 years were asked about a lifetime history of PID diagnosis. Based on these data, the estimated prevalence of self-reported lifetime PID was 4.4% in sexually experienced women of reproductive age (18-44 years). The prevalence of self-reported lifetime PID was highest in women at increased risk, such as women reporting a previous sexually transmitted infection (STI) diagnosis. Stratified by race/ethnicity and having a previous STI diagnosis, non-Hispanic black (black) and non-Hispanic white (white) women reporting a previous STI diagnosis had nearly equal self-reported lifetime PID prevalence (10.0% versus 10.3%). However, the lifetime prevalence of PID among black women was 2.2 times that among white women if no previous STI was diagnosed (6.0% versus 2.7%). These findings suggest that PID is prevalent and associated with previous STI diagnoses; therefore, it is important for clinicians to screen female patients for chlamydia and gonorrhea to reduce the incidence of PID.

The Expedited Partner Therapy Continuum: A Conceptual Framework to Guide Programmatic Efforts to Increase Partner Treatment.

BACKGROUND: Expedited partner therapy (EPT) is a partner treatment strategy wherein health care providers give patients antibiotics or a prescription to deliver to their sex partners as treatment, without an intervening medical evaluation. METHODS: We used PubMed and the Cochrane database to systematically identify published articles about EPT after 2006 and randomized controlled trials before that date; we also sought conference abstracts and unpublished data from 2013 to 2014. We described key steps in a hypothetical "EPT continuum," beginning with diagnosis of Chlamydia trachomatis or Neisseria gonorrhoeae in a patient and ending with treatment for the patient's sex partner(s) with EPT. All reports were abstracted for a set of defined measures and related interventions. RESULTS: We reviewed 100 published articles, unpublished data reports, and conference abstracts; 42 met the inclusion criteria and provided measures of the following: provider uptake and offer of EPT, patient acceptance and receipt of EPT, patient delivery of EPT to sex partners, and partner receipt of EPT and treatment. Implementation phase, populations, settings, and methodologies varied across reports. Providers' uptake and offer of EPT are rate-limiting steps in the EPT continuum and were the focus of all 5 programmatic interventions we identified. There were 7 population-based measures of patient receipt of EPT; however, several of the patient populations overlapped. CONCLUSIONS: A heterogenous body of literature describes EPT, and variation in study population, setting, and metrics limit generalizability. Programs seeking to increase partner treatment should focus their efforts on provider uptake and offer and should use population-based measures to monitor EPT use.

Staphylococcus aureus Colonization and Strain Type at Various Body Sites among Patients with a Closed Abscess and Uninfected Controls at U.S. Emergency Departments.

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is a prevalent cause of skin and soft tissue infections (SSTI), but the association between CA-MRSA colonization and infection remains uncertain. We studied the carriage frequency at several body sites and the diversity of S. aureus strains from patients with and without SSTI. Specimens from the nares, throat, rectum, and groin of case subjects with a closed skin abscess (i.e., without drainage) and matched control subjects without a skin infection (n = 147 each) presenting to 10 U.S. emergency departments were cultured using broth enrichment; wound specimens were cultured from abscess cases. Methicillin resistance testing and spa typing were performed for all S. aureus isolates. S. aureus was found in 85/147 (57.8%) of abscesses; 49 isolates were MRSA, and 36 were methicillin-susceptible S. aureus (MSSA). MRSA colonization was more common among cases (59/147; 40.1%) than among controls (27/147; 18.4%) overall (P < 0.001) and at each body site; no differences were observed for MSSA. S. aureus-infected subjects were usually (75/85) colonized with the infecting strain; among MRSA-infected subjects, this was most common in the groin. The CC8 lineage accounted for most of both infecting and colonizing isolates, although more than 16 distinct strains were identified. Nearly all MRSA infections were inferred to be USA300. There was more diversity among colonizing than infecting isolates and among those isolated from controls versus cases. CC8 S. aureus is a common colonizer of persons with and without skin infections. Detection of S. aureus colonization, and especially MRSA, may be enhanced by extranasal site culture.

Infection prevention practices in neonatal intensive care units reporting to the national healthcare safety network.

BACKGROUND: Patients in the neonatal intensive care unit (NICU) are at high risk for healthcare-associated infections. Variability in reported infection rates among NICUs exists, possibly related to differences in prevention strategies. A better understanding of current prevention practices may help identify prevention gaps and areas for further research. METHODS: We surveyed infection control staff in NICUs reporting to the National Healthcare Safety Network (NHSN) to assess strategies used to prevent methicillin-resistant Staphylococcus aureus (MRSA) transmission and central line-associated bloodstream infections in NICUs. RESULTS: Staff from 162 of 342 NICUs responded (response rate, 47.3%). Most (92.3%) NICUs use central line insertion and maintenance bundles, but maintenance practices varied, including agents used for antisepsis and frequency of dressing changes. Forty-two percent reported routine screening for MRSA colonization upon admission for all patients. Chlorhexidine gluconate (CHG) use for central line care for at least 1 indication (central line insertion, dressing changes, or port/cap antisepsis) was reported in 82 NICUs (51.3%). Among sixty-five NICUs responding to questions on CHG use restrictions, 46.2% reported no restrictions. CONCLUSIONS: Our survey illustrated heterogeneity of CLABSI and MRSA prevention practices and underscores the need for further research to define optimal strategies and evidence-based prevention recommendations for neonates.

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

BACKGROUND: Effective 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. METHODS: We 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. RESULTS: The 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. CONCLUSIONS: Personal 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. CLINICAL TRIALS REGISTRATION: NCT01105767.

Expedited partner therapy in federally qualified health centers--New York City, 2012.

BACKGROUND: Management of patients' sex partners is a critical element of sexually transmitted disease (STD) control. Expedited partner therapy (EPT), a practice in which patients deliver medication or a prescription directly to their partners, is one option for partner management. As of 2009, New York State law specifically allows EPT for chlamydial infection. Federally qualified health centers (FQHCs) in New York City (NYC) care for patients at risk for STDs. We describe the policies and practices surrounding EPT and other STD management in NYC FQHCs. METHODS: In 2012, we surveyed medical directors at all NYC FQHC parent entities and clinicians at a sample of their corresponding clinical sites about written policies and actual practices regarding EPT for chlamydial infection and other STD management. RESULTS: Twenty-two entities (22/29; 76%) and 51 sites (51/72; 70%) responded to the survey. More than half of entities have a written policy permitting EPT, and 80% of sites provide EPT. Most entity policies allow EPT for, and most sites provide EPT to, adolescents and adults with both opposite-sex and/or same-sex partners. Most sites use electronic health records and provide EPT by prescriptions, and one third of sites do not provide educational materials with EPT. CONCLUSIONS: Our results indicate widespread EPT provision by NYC FQHCs; however, areas for improvement exist, specifically in following guidelines that recommend providing educational materials with EPT and do not recommend EPT for men with male partners. The use of prescriptions for EPT and electronic health records were identified as potential barriers to EPT provision.

Trends in invasive methicillin-resistant Staphylococcus aureus infections.

OBJECTIVE: To describe trends in the incidence of invasive methicillin-resistant Staphylococcus aureus (MRSA) infections in children during 2005-2010. METHODS: We evaluated reports of invasive MRSA infections in pediatric patients identified from population-based surveillance during 2005-2010. Cases were defined as isolation of MRSA from a normally sterile site and classified on the basis of the setting of the positive culture and presence or absence of health care exposures. Estimated annual changes in incidence were determined by using regression models. National age- and race-specific incidences for 2010 were estimated by using US census data. RESULTS: A total of 876 pediatric cases were reported; 340 (39%) were among infants. Overall, 35% of cases were hospital-onset, 23% were health care-associated community-onset, and 42% were community-associated (CA). The incidence of invasive CA-MRSA infection per 100000 children increased from 1.1 in 2005 to 1.7 in 2010 (modeled yearly increase: 10.2%; 95% confidence interval: 2.7%-18.2%). No significant trends were observed for health care-associated community-onset and hospital-onset cases. Nationally, estimated invasive MRSA incidence in 2010 was higher among infants aged <90 days compared with older infants and children (43.9 vs 2.0 per 100000) and among black children compared with other races (6.7 vs 1.6 per 100000). CONCLUSIONS: Invasive MRSA infection in children disproportionately affects young infants and black children. In contrast to reports of declining incidence among adults, there were no significant reductions in health care-associated MRSA infections in children. Concurrently, the incidence of CA-MRSA infections has increased, underscoring the need for defining optimal strategies to prevent MRSA infections among children with and without health care exposures.

Methicillin-resistant Staphylococcus aureus colonization of the groin and risk for clinical infection among HIV-infected adults.

Data on the interaction between methicillin-resistant Staphylococcus aureus (MRSA) colonization and clinical infection are limited. During 2007-2008, we enrolled HIV-infected adults in Atlanta, Georgia, USA, in a prospective cohort study. Nares and groin swab specimens were cultured for S. aureus at enrollment and after 6 and 12 months. MRSA colonization was detected in 13%-15% of HIV-infected participants (n=600, 98% male) at baseline, 6 months, and 12 months. MRSA colonization was detected in the nares only (41%), groin only (21%), and at both sites (38%). Over a median of 2.1 years of follow-up, 29 MRSA clinical infections occurred in 25 participants. In multivariate analysis, MRSA clinical infection was significantly associated with MRSA colonization of the groin (adjusted risk ratio 4.8) and a history of MRSA infection (adjusted risk ratio 3.1). MRSA prevention strategies that can effectively prevent or eliminate groin colonization are likely necessary to reduce clinical infections in this population.

Impact of USA300 methicillin-resistant Staphylococcus aureus on clinical outcomes of patients with pneumonia or central line-associated bloodstream infections.

BACKGROUND: The USA300 methicillin-resistant Staphylococcus aureus (MRSA) strain, which initially emerged as a cause of community-associated infections, has recently become an important pathogen in healthcare-associated infections (HAIs). However, its impact on patient outcomes has not been well studied. We evaluated patients with invasive MRSA infections to assess differences in outcomes between infections caused by USA100 and those caused by USA300. METHODS: Population-based data for invasive MRSA infections were used to identify 2 cohorts: (1) nondialysis patients with central line-associated bloodstream infections (CLABSIs) and (2) patients with community-onset pneumonia (PNEUMO) during 2005-2007 from 6 US metropolitan areas. Medical records of patients with confirmed MRSA USA100 or USA300 infection were reviewed. Logistic regression and, when appropriate, survival analysis was performed to evaluate mortality, early and late complications, and length of stay. RESULTS: A total of 236 and 100 patients were included in the CLABSI and PNEUMO cohorts, respectively. USA300 was the only independent predictor of early complications for PNEUMO patients (odds ratio [OR], 2.6; P = .02). Independent predictors of CLABSI late complications included intensive care unit (ICU) admission before MRSA culture (adjusted OR [AOR], 2.1; P= .01) and Charlson comorbidity index (AOR, 2.6; P = .003), but not strain type. PNEUMO patients were significantly more likely to die if they were older (P = .02), black (P < .001), or infected with USA100 strain (P = .02), whereas those with CLABSI were more likely to die if they were older (P < .001), had comorbidities (P < .001), or had an ICU admission before MRSA culture (P = .001). CONCLUSIONS: USA300 was associated with early complications in PNEUMO patients. However, it was not associated with mortality for either PNEUMO or CLABSI patients. Concerns regarding higher mortality from HAIs caused by USA300 may not be warranted.

Prevalence of methicillin-resistant staphylococcus aureus as an etiology of community-acquired pneumonia.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of skin infections. Recent case series describe severe community-acquired pneumonia (CAP) caused by MRSA, but the prevalence and risk factors are unknown. METHODS: We prospectively enrolled adults hospitalized with CAP from 12 university-affiliated emergency departments during the winter-spring of 2006 and 2007. Clinical information and culture results were collected, and factors associated with MRSA were assessed. RESULTS: Of 627 patients, 595 (95%) had respiratory (50%) and/or blood cultures (92%) performed. A pathogen was identified in 102 (17%); MRSA was identified in 14 (2.4%; range by site, 0%-5%) patients and in 5% of patients admitted to the intensive care unit. Two (14%) MRSA pneumonia patients died. All 9 MRSA isolates tested were pulsed-field type USA300. Features significantly associated with isolation of MRSA (as compared with any other or no pathogen) included patient history of MRSA; nursing home admission in the previous year; close contact in the previous month with someone with a skin infection; multiple infiltrates or cavities on chest radiograph; and comatose state, intubation, receipt of pressors, or death in the emergency department. CONCLUSIONS: Methicillin-resistant Staphylococcus aureus remains an uncommon cause of CAP. Detection of MRSA was associated with more severe clinical presentation.

Comparison of Staphylococcus aureus from skin and soft-tissue infections in US emergency department patients, 2004 and 2008.

BACKGROUND: In the past decade, new methicillin-resistant Staphylococcus aureus (MRSA) strains have emerged as a predominant cause of community-associated skin and soft-tissue infections (SSTIs). Little information exists regarding trends in MRSA prevalence and molecular characteristics or regarding antimicrobial susceptibility profiles of S. aureus isolates. METHODS: We enrolled adults with acute, purulent SSTIs presenting to a US network of 12 emergency departments during August 2008. Cultures and clinical information were collected. S. aureus isolates were characterized by antimicrobial susceptibility testing, pulsed-field gel electrophoresis, and toxin genes detection. The prevalence of S. aureus and MRSA and isolate genetic characteristics and susceptibilities were compared with those from a similar study conducted in August 2004. RESULTS: The prevalence of MRSA was 59% among all SSTIs during both study periods; however, the prevalence by site varied less in 2008 (38%-84%), compared with 2004 (15%-74%). Pulsed-field type USA300 continued to account for almost all MRSA isolates (98%). Susceptibility to trimethoprim-sulfamethoxazole, clindamycin, and tetracycline among MRSA isolates remained greater than 90% in 2008. A higher proportion of MRSA infections were treated with an agent to which the infecting isolate was susceptible in vitro in 2008 (97%), compared with 2004 (57%). CONCLUSIONS: Similar to 2004, MRSA remained the most common identifiable cause of purulent SSTIs among patients presenting to a network of US emergency departments in 2008. The infecting MRSA isolates continued to be predominantly pulsed-field type USA300 and susceptible to recommended non-ß-lactam oral agents. Clinician prescribing practices have shifted from MRSA-inactive to MRSA-active empirical antimicrobial regimens.

Risk factors for household transmission of community-associated methicillin-resistant Staphylococcus aureus.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a community pathogen. Community-associated (CA) MRSA infections have occurred among multiple members of a household. We describe the incidence of and risk factors for MRSA colonization among household contacts of children with CA-MRSA infections. METHODS: MRSA-infected children <18 years of age who lacked established healthcare-associated MRSA risk factors were identified through surveillance at 12 Minnesota hospital laboratories. Nasal swab specimens and information on medical history and hygiene behaviors were collected from case-patients and enrolled household contacts during home visits. S. aureus isolates obtained from nasal cultures were screened for oxacillin resistance. RESULTS: In all, 236 households consisting of 236 case-patients and 712 household contacts were enrolled. Home visits were conducted on an average of 69 days after the onset of symptom in case-patients (range: 16-178 days). Twenty-nine (13%) case-patients and 82 (12%) household contacts had MRSA nasal colonization. Nasal MRSA colonization in ≥ 1 household contact occurred in 58 (25%) households. Household contacts who assisted the case-patient to bathe or who shared balms/ointments/lotion with the case-patient were more likely to be colonized (P < 0.01, P < 0.05), whereas those who reported using antibacterial versus nonantibacterial soap for hand washing were less likely to be colonized (P < 0.05) with MRSA clonally related to the case-patient infection isolate. CONCLUSIONS: Only 13% of case-patients had MRSA nasal colonization on an average of 69 days after their initial MRSA infection. CA-MRSA colonization may be short-lived or may occur at non-nasal sites. One quarter of households had at least one household contact colonized with MRSA. Modifiable behaviors, such as sharing personal items, may contribute to transmission.

Clinical practice guidelines by the infectious diseases society of america for the treatment of methicillin-resistant Staphylococcus aureus infections in adults and children.

Evidence-based guidelines for the management of patients with methicillin-resistant Staphylococcus aureus (MRSA) infections were prepared by an Expert Panel of the Infectious Diseases Society of America (IDSA). The guidelines are intended for use by health care providers who care for adult and pediatric patients with MRSA infections. The guidelines discuss the management of a variety of clinical syndromes associated with MRSA disease, including skin and soft tissue infections (SSTI), bacteremia and endocarditis, pneumonia, bone and joint infections, and central nervous system (CNS) infections. Recommendations are provided regarding vancomycin dosing and monitoring, management of infections due to MRSA strains with reduced susceptibility to vancomycin, and vancomycin treatment failures.