Search

Abstract The influence of greenhouse warming on mesoscale air-sea interactions, crucial for modulating ocean circulation and climate variability, remains largely unexplored due to the limited resolution of current climate models. Additionally, there is a lack of theoretical frameworks for assessing changes in mesoscale coupling due to warming. Here, we address these gaps by analyzing eddy-resolving high-resolution climate simulations and observations, focusing on the mesoscale thermal interaction dominated by mesoscale sea surface temperature (SST) and latent heat flux (LHF) coupling in winter. Our findings reveal a consistent increase in mesoscale SST-LHF coupling in the major western boundary current regions under warming, characterized by a heightened nonlinearity between warm and cold eddies and a more pronounced enhancement in the northern hemisphere. To understand the dynamics, we develop a theoretical framework that links mesoscale thermal coupling changes to large-scale factors, which indicates that the projected changes are collectively determined by historical background wind, SST, and the rate of SST warming. Among these factors, the large-scale SST and its warming rate are the primary drivers of hemispheric asymmetry in mesoscale coupling intensification. This study introduces a simplified approach for assessing the projected mesoscale thermal coupling changes in a warming world.

Abstract The East China Sea Kuroshio (ECS‐Kuroshio) and the Ryukyu Current are the major poleward heat carriers in the North Pacific. Anomalous changes of ECS‐Kuroshio and Ryukyu Current could exert substantial influence on the climate in mid‐latitude regions. However, owing to limited observations and coarse resolution of climate models, how they might change under anthropogenic warming remains unknown. Here, we find an accelerating ECS‐Kuroshio (1.5 Sv) and a decelerating (−2.2 Sv) Ryukyu Current using in‐situ observation during 1958–2022, equivalent to 7% strengthening and 20% weakening in the 65 years. The trend is also simulated by four high‐resolution climate models, with multi‐model ensemble‐mean acceleration (deceleration) of the ECS‐Kuroshio (Ryukyu Current) of 1.2 ± 0.6 Sv (−6.2 ± 2.5 Sv) over 1950–2050. The weakening subtropical wind field reduces their summed transport o. Enhanced stratification, which induces uplift of current system and weaker topography‐flow interaction, leads to the intensifying ECS‐Kuroshio and disappearing Ryukyu Current.

Abstract Global surface temperature short‐term trends fluctuate between cooling and fast‐warming under the combined action of external forcing and internal variability, significantly influencing the detectability of near‐term climate change. A key driver of these variations is anthropogenic aerosols (AAs), which have undergone a non‐monotonic evolution with rapid reduction in recent decades. However, their reduction is projected to decelerate under a high carbon emission scenario, yet the impact on surface temperature trends remains unknown. Here, using initial‐perturbation large ensembles, we find that future slowdown in AA reduction over Europe and North America expedites the subpolar North Atlantic surface warming by intensifying the Atlantic meridional overturning circulation. Further, it accelerates the South Indian Ocean and Southern Ocean surface warming through positive low‐cloud feedback and oceanic dynamical adjustment, triggered by the poleward migration of westerlies under interhemispheric energy constraint. These AA‐driven warmings exacerbate greenhouse warming, significantly enhancing the detectability of local decadal warming trends.

Abstract Air‐sea exchanges across oceanic fronts are critical in powering cloud formation, precipitation, and atmospheric storms. Oceanic submesoscale fronts of scales 1–10 km are characterized by strong sea surface temperature (SST) gradients. However, it remains elusive how submesoscale fronts affect the overlying atmosphere due to a lack of high‐resolution observations or models. Based on rare high‐resolution in situ observations in the Kuroshio Extension region, we quantify the air‐sea exchanges across an oceanic submesoscale front. The cross‐front SST and turbulent heat flux gradients reaches 2.4°C/km and 47 W/m2/km, respectively, far stronger than that typically found in mesoscale‐resolving products. The stronger SST gradient drives substantially stronger air‐sea fluxes and vertical mixing than mesoscale fronts, enhancing cloud formations. The intense air‐sea exchanges across submesoscale fronts are confirmed in idealized model simulations, but not resolved in mesoscale‐resolving climate models. Our finding provides essential knowledge for improving simulations of cloud formation, precipitation, and storms in climate models.

Abstract Extreme atmospheric rivers (EARs) are responsible for most of the severe precipitation and disastrous flooding along the coastal regions in midlatitudes. However, the current non-eddy-resolving climate models severely underestimate (~50%) EARs, casting significant uncertainties on their future projections. Here, using an unprecedented set of eddy-resolving high-resolution simulations from the Community Earth System Model simulations, we show that the models’ ability of simulating EARs is significantly improved (despite a slight overestimate of ~10%) and the EARs are projected to increase almost linearly with temperature warming. Under the Representative Concentration Pathway 8.5 warming scenario, there will be a global doubling or more of the occurrence, integrated water vapor transport and precipitation associated with EARs, and a more concentrated tripling for the landfalling EARs, by the end of the 21st century. We further demonstrate that the coupling relationship between EARs and storms will be reduced in a warming climate, potentially influencing the predictability of future EARs.

Abstract Marine heatwaves (MHWs) are prolonged extreme warm water events in the ocean, exerting devastating impacts on marine ecosystems. A comprehensive knowledge of physical processes controlling MHW life cycles is pivotal to improve MHW forecast capacity, yet it is still lacking. Here, we use a historical simulation from a global eddy-resolving climate model with improved representation of MHWs, and show that heat flux convergence by oceanic mesoscale eddies acts as a dominant driver of MHW life cycles over most parts of the global ocean. In particular, the mesoscale eddies make an important contribution to growth and decay of MHWs, whose characteristic spatial scale is comparable or even larger than that of mesoscale eddies. The effect of mesoscale eddies is spatially heterogeneous, becoming more dominant in the western boundary currents and their extensions, the Southern Ocean, as well as the eastern boundary upwelling systems. This study reveals the crucial role of mesoscale eddies in controlling the global MHW life cycles and highlights that using eddy-resolving ocean models is essential, albeit not necessarily fully sufficient, for accurate MHW forecasts.

Ocean thermal energy conversion (OTEC) resources provide a renewable solution to fuel our future. Here the authors show a significant increase of OTEC resources under greenhouse warming with the increasing rate regulated by oceanic eddies.

Under global warming, increased variability in El Niño sea surface temperature was projected to be detectable by about 2070. Here the authors show that the increased variability of a type of more impactful El Niño events is likely detectable by 2030.

Oceanic mesoscale eddies are important dynamical processes in the Southern Ocean. Using high-resolution (∼0.1° for the ocean) Community Earth System Model (CESM-HR) simulations under a high-carbon emission scenario, we investigate the role of mesoscale eddies in regulating the response of the Subantarctic Front (SAF) to global warming. The CESM-HR simulates more realistic oceanic fronts and mesoscale eddies in the Southern Ocean than a coarse-resolution (∼1° for the ocean) CESM. Under global warming, the SAF is projected to intensify. The mean flow temperature advection intensifies the front, whereas the mesoscale-eddy-induced temperature advection and atmospheric dampening play primary (∼67%) and secondary (∼28%) roles in counteracting the effect of mean flow temperature advection. Our study suggests the importance of mesoscale eddies on inhibiting the SAF intensification under global warming and necessity of mesoscale-eddy-resolving simulations for faithful projection of future climate changes in the Southern Ocean.

The decadal-scale global-mean surface temperature (GMST) trend fluctuates between rapid-warming, slow-warming and cooling under the combined action of external forcing (EX) and internal variability. However, the principal contributors to the time-varying trends of GMST across decadal scales in current and future climates remain elusive. Here, by leveraging observations and initial-condition large ensembles, we unravel that historical GMST trend fluctuations are predominantly driven by EX on timescales exceeding ∼9 years within the current climate, with anthropogenic and volcanic aerosols being the primary drivers. However, in the warming climate, the significant contribution of EX on decadal scales is projected to decrease. This is primarily due to anthropogenic aerosol mitigation efforts and the absence of unpredictable volcanism. Despite the continuous increase in greenhouse gases, these factors are expected to delay the emergence of EX-dominance to ∼14-year timescale. Our results quantitatively underscore the pivotal role of the EX in modulating GMST trend fluctuations and its potential weakening at decadal scales in the warming climate, indicating that predicting near-term changes in GMST may become less certain in the future.

The warm Arctic-cold Eurasia (WACE) pattern of surface air temperature anomalies is a prominent feature of the Eurasian climate variations during boreal winter. The interannual WACE anomalies are accompanied by sea ice loss in the Barents-Kara (BK) seas, however, the causality between them remains controversial because of large internal atmospheric variability over subarctic Eurasia in winter. Here we disentangle the contribution of BK sea ice loss to the WACE anomalies based on a statistical decomposition approach. An anticyclonic circulation anomaly over subarctic Eurasia that forces the WACE anomalies is found to reach its peak 3 d prior to BK sea ice loss. After excluding this prior atmospheric forcing signature, the East Asian cooling matures about 15 d later as a result of the weakened moisture transport associated with the enhanced BK downstream ridge and East Asian trough due to BK sea ice loss. The results suggest that BK sea ice loss contributes ∼65% and ∼81% of the WACE-related East Asian cooling and Arctic warming at interannual timescale, respectively, whereas the WACE-related cooling over central Eurasia primarily results from internal atmospheric variability. Such submonthly lagged East Asia cooling caused by BK sea ice loss could be helpful in predicting winter extreme cold events over East Asia.

Abstract We present an unprecedented set of high‐resolution climate simulations, consisting of a 500‐year pre‐industrial control simulation and a 250‐year historical and future climate simulation from 1850 to 2100. A high‐resolution configuration of the Community Earth System Model version 1.3 (CESM1.3) is used for the simulations with a nominal horizontal resolution of 0.25° for the atmosphere and land models and 0.1° for the ocean and sea‐ice models. At these resolutions, the model permits tropical cyclones and ocean mesoscale eddies, allowing interactions between these synoptic and mesoscale phenomena with large‐scale circulations. An overview of the results from these simulations is provided with a focus on model drift, mean climate, internal modes of variability, representation of the historical and future climates, and extreme events. Comparisons are made to solutions from an identical set of simulations using the standard resolution (nominal 1°) CESM1.3 and to available observations for the historical period to address some key scientific questions concerning the impact and benefit of increasing model horizontal resolution in climate simulations. An emerging prominent feature of the high‐resolution pre‐industrial simulation is the intermittent occurrence of polynyas in the Weddell Sea and its interaction with an Interdecadal Pacific Oscillation. Overall, high‐resolution simulations show significant improvements in representing global mean temperature changes, seasonal cycle of sea‐surface temperature and mixed layer depth, extreme events and in relationships between extreme events and climate modes.

Marine heatwaves (MHWs) can cause various adverse effects on marine ecosystems associated with complicated social ramifications. It has been well established that the gradually rising sea surface temperature (SST) due to anthropogenic carbon emission will cause an increase of the MHW duration and intensity. However, for species with strong adaptation capacity or mobility, MHW changes due to the altered SST variability under greenhouse warming are more crucial but so far remain poorly assessed. Under the high carbon emission scenario, we show that the cumulative duration (intensity) of MHWs, with the effect of secular SST increase excluded, is projected to be 60% (100%) higher by the end of this century than in the 1990s due to an amplified SST seasonal cycle. This increase becomes more evident for stronger MHWs, reaching up to 8 (30) folds for the extreme MHW category. The amplified SST seasonal cycle also causes pronounced seasonality of MHWs, making them more active in summer-autumn than winter-spring. Our results suggest that MHWs are likely to have increasingly devastating impacts on a wide range of marine species in the future without taking effective steps for carbon emission reduction.

It is unclear how extreme positive Indian Ocean Dipole will respond to 1.5 °C of warming. Here the authors show that the frequency of these events increases linearly with warming, doubling at 1.5 °C from the pre-industrial level, but plateaus thereafter.

The effectiveness of HIV antibody counseling and testing as a prevention intervention is limited: persons testing seronegative do not usually change their risk behaviors, some actually increase their risk behaviors, and decreases in risk behaviors are usually short-lived. Referrals to additional prevention and other needed services are therefore recommended, although the extent and determinants of referral provision for persons testing seronegative are unknown. We assessed the prevalence of referrals and the association between risk behaviors and prevention referrals among seronegatives. We reviewed HIV testing and referral data on all persons receiving confidential seronegative test results in San Francisco (SF) in the first 10 months of 1995 (n = 5,595), and gathered more detailed referral information at the municipal STD clinic from November 1995 through May 1996 (n = 747). The overall prevalence of referrals was low: a referral was given to 19.1% of the SF sample and 10.6% of the STD clinic sample; 15.4% of the SF sample and 5.9% of the STD clinic sample received a prevention referral. Injection drug users (IDUs) were the most likely to receive a prevention referral (48.5% of SF IDUs, 36.4% of STD clinic IDUs); men having sex with men and women with high-risk partners were also more likely to get a prevention referral than others. For SF IDUs, unsafe sex and needle sharing were not associated with an increased likelihood of receiving a prevention referral. Opportunities to link high-risk clients from counseling and testing to HIV prevention services are being missed. The referral component of HIV counseling and testing should be improved. [ABSTRACT FROM AUTHOR]

Competing Interests: Conflict of Interest and Sources of Funding: None declared.

Competing Interests: Conflict of interest and Sources of Funding: None declared.

This report provides new CDC recommendations for tests that can support a diagnosis of syphilis, including serologic testing and methods for the identification of the causative agent Treponema pallidum. These comprehensive recommendations are the first published by CDC on laboratory testing for syphilis, which has traditionally been based on serologic algorithms to detect a humoral immune response to T. pallidum. These tests can be divided into nontreponemal and treponemal tests depending on whether they detect antibodies that are broadly reactive to lipoidal antigens shared by both host and T. pallidum or antibodies specific to T. pallidum, respectively. Both types of tests must be used in conjunction to help distinguish between an untreated infection or a past infection that has been successfully treated. Newer serologic tests allow for laboratory automation but must be used in an algorithm, which also can involve older manual serologic tests. Direct detection of T. pallidum continues to evolve from microscopic examination of material from lesions for visualization of T. pallidum to molecular detection of the organism. Limited point-of-care tests for syphilis are available in the United States; increased availability of point-of-care tests that are sensitive and specific could facilitate expansion of screening programs and reduce the time from test result to treatment. These recommendations are intended for use by clinical laboratory directors, laboratory staff, clinicians, and disease control personnel who must choose among the multiple available testing methods, establish standard operating procedures for collecting and processing specimens, interpret test results for laboratory reporting, and counsel and treat patients. Future revisions to these recommendations will be based on new research or technologic advancements for syphilis clinical laboratory science., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No conflicts of interest were disclosed.

These guidelines for the treatment of persons who have or are at risk for sexually transmitted infections (STIs) were updated by CDC after consultation with professionals knowledgeable in the field of STIs who met in Atlanta, Georgia, June 11-14, 2019. The information in this report updates the 2015 guidelines. These guidelines discuss 1) updated recommendations for treatment of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis; 2) addition of metronidazole to the recommended treatment regimen for pelvic inflammatory disease; 3) alternative treatment options for bacterial vaginosis; 4) management of Mycoplasma genitalium; 5) human papillomavirus vaccine recommendations and counseling messages; 6) expanded risk factors for syphilis testing among pregnant women; 7) one-time testing for hepatitis C infection; 8) evaluation of men who have sex with men after sexual assault; and 9) two-step testing for serologic diagnosis of genital herpes simplex virus. Physicians and other health care providers can use these guidelines to assist in prevention and treatment of STIs., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Christina Muzny reports other support from CDC, during the conduct of the study; grants from the National Institutes of Health/National Institute of Allergy and Infectious Diseases and Lupin Pharmaceuticals; personal fees from Lupin Pharmaceuticals, PhagoMed, Cepheid, and Beckton Dickinson; and personal fees and other support from Roche Diagnostics, Abbott Molecular, and BioFire Diagnostics, outside the submitted work. Hilary Reno reports grants from Hologic, outside the submitted work. Christine Johnston reports other support from CDC, during the conduct of the study; received research funding from Sanofi-Pasteur; royalties from UpToDate; and personal fees from MedPace, Gilead, AbbVie, and UpToDate, outside the submitted work.

This report (hereafter referred to as STD QCS) provides CDC recommendations to U.S. health care providers regarding quality clinical services for sexually transmitted diseases (STDs) for primary care and STD specialty care settings. These recommendations complement CDC's Sexually Transmitted Diseases Treatment Guidelines, 2015 (hereafter referred to as the STD Guidelines), a comprehensive, evidence-based reference for prevention, diagnosis, and treatment of STDs. STD QCS differs from the STD Guidelines by specifying operational determinants of quality services in different types of clinical settings, describing on-site treatment and partner services, and indicating when STD-related conditions should be managed through consultation with or referral to a specialist. These recommendations might also help in the development of clinic-level policies (e.g., standing orders, express visits, specimen panels, and reflex testing) that can facilitate implementation of the STD Guidelines. CDC organized the recommendations for STD QCS into eight sections: 1) sexual history and physical examination, 2) prevention, 3) screening, 4) partner services, 5) evaluation of STD-related conditions, 6) laboratory, 7) treatment, and 8) referral to a specialist for complex STD or STD-related conditions.CDC developed the recommendations by synthesizing relevant, evidence-based guidelines and recommendations issued by other experts; reviewing current practice in the United States; soliciting Delphi ratings by subject matter experts on STD care in primary care and STD specialty care settings; discussing the scientific evidence supporting the proposed recommendations at a consultation meeting of experts and institutional stakeholders held November 20, 2015, in Atlanta, Georgia; conducting peer reviews of draft recommendations and supporting evidence; and discussing draft recommendations and supporting evidence during meetings of the CDC/Health Resources and Services Administration Advisory Committee on HIV, Viral Hepatitis, and STD Prevention and Treatment STD Work Group. These recommendations are intended to help health care providers in primary care or STD specialty care settings offer STD services at their clinical settings and to help the persons seeking care live safer, healthier lives by preventing and treating STDs and related complications., Competing Interests: CDC, the planners, and the presenters disclose they have no financial interests or other relationships with the manufacturers of commercial products, suppliers of commercial services, or commercial supporters with the following exceptions: Kevin Ault, National Institute for Allergy and Infectious Diseases funding; Laura Bachmann, research grants from Cepheid and Melinta; Ronald Goldschmidt, Health Resources and Services Administration (HRSA) funding; Charlene Flash, National Institutes of Health, HRSA, American Medical Association, and Gilead funding; Michael Mugavero, National Institutes of Health, Agency for Healthcare Research and Quality, and Gilead funding.

It is estimated that approximately 20 million new sexually transmitted infections (STIs) occur each year in the United States. The federally funded sexually transmitted disease prevention program implemented by Centers for Disease Control and Prevention is primarily focused on the prevention and control of the three most common bacterial STIs: syphilis, gonorrhea, and chlamydia. A range of factors facilitate the transmission and acquisition of STIs, including syphilis. In 1999, Centers for Disease Control and Prevention launched the National Campaign to Eliminate Syphilis from the United States. The strategies were familiar to public health in general and to sexually transmitted disease control in particular: (1) enhanced surveillance, (2) expanded clinical and laboratory services, ((3) enhanced health promotion, (4) strengthened community involvement and partnerships, and (5) rapid outbreak response. This national commitment to syphilis elimination was not the first effort, and like others before it too did not succeed. However, the lessons learned from this most recent campaign can inform the way forward to a more comprehensive approach to the prevention and control of STIs and improvement in the nation's health.

These guidelines for the treatment of persons who have or are at risk for sexually transmitted diseases (STDs) were updated by CDC after consultation with a group of professionals knowledgeable in the field of STDs who met in Atlanta on April 30-May 2, 2013. The information in this report updates the Sexually Transmitted Diseases Treatment Guidelines, 2010 (MMWR Recomm Rep 2010;59 [No. RR-12]). These updated guidelines discuss 1) alternative treatment regimens for Neisseria gonorrhoeae; 2) the use of nucleic acid amplification tests for the diagnosis of trichomoniasis; 3) alternative treatment options for genital warts; 4) the role of Mycoplasma genitalium in urethritis/cervicitis and treatment-related implications; 5) updated HPV vaccine recommendations and counseling messages; 6) the management of persons who are transgender; 7) annual testing for hepatitis C in persons with HIV infection; 8) updated recommendations for diagnostic evaluation of urethritis; and 9) retesting to detect repeat infection. Physicians and other health-care providers can use these guidelines to assist in the prevention and treatment of STDs.

Background: Neisseria gonorrhoeae has progressively developed resistance to sulfonamides, penicillin, tetracycline and fluoroquinolones, and gonococcal susceptibility to cephalosporins has been declining worldwide., Methods: We described trends in gonococcal antimicrobial susceptibility in the USA from January 2006 through June 2012. Susceptibility data for cefixime, ceftriaxone, azithromycin, penicillin, tetracycline and ciprofloxacin were obtained from the Gonococcal Isolate Surveillance Project (GISP), a sentinel surveillance system that monitors antimicrobial susceptibility in urethral gonococcal isolates collected from symptomatic men at 25-30 sexually transmitted disease clinics throughout the USA., Results: The percentage of isolates with elevated cefixime minimum inhibitory concentrations (MICs) (≥ 0.25 µg/mL) increased from 0.1% in 2006 to 1.4% in 2010-2011 and was 1.1% in the first 6 months of 2012. The percentage with elevated ceftriaxone MICs (≥ 0.125 µg/mL) increased from 0.1% in 2006 to 0.3%-0.4% during 2009 through the first 6 months of 2012. There were no temporal trends in the prevalence of elevated azithromycin MICs (≥ 2 µg/mL) (0.2%-0.5%). The prevalence of resistance remained high for penicillin (11.2%-13.2%), tetracycline (16.7%-22.8%) and ciprofloxacin (9.6%-14.8%)., Conclusions: The proportion of gonococcal isolates with elevated cephalosporin MICs increased from 2006 to 2010, but plateaued during 2011 and the first 6 months of 2012. Resistance to previously recommended antimicrobials has persisted. As the number of antimicrobials available for gonorrhoea treatment dwindles, surveillance systems such as GISP will be critical to detect emerging resistance trends and guide treatment decisions.

We report on the first Neisseria gonorrhoeae isolate in the United States identified with high-level resistance to azithromycin. This report discusses the epidemiologic case investigation, the molecular studies of resistance-associated mutations and N. gonorrhoeae multiantigen sequence typing, and challenges posed by emerging gonococcal antimicrobial resistance.

Purpose: To aid front-line program administrators and providers in adopting national reproductive health recommendations, this exploratory case study examines the implementation of service integration and teen friendliness as strategies to improve adolescent sexual and reproductive health., Methods: The project team conducted semi-structured interviews with administrators, providers, and adolescent clients from 10 clinical adolescent sexual and reproductive health service agencies in Alameda County, California. Programs were placed into a topology of integrated service delivery models. The teen friendliness of each program was assessed. Spearman rank correlations were calculated to evaluate the relationship between integration and teen friendliness., Results: Clinical programs exhibited a great range of service delivery models within the integration topology. Human immunodeficiency virus (HIV) counseling and testing services were poorly integrated into clinic services. Teen friendliness and integration showed a negative, but not statistically significant, correlation (R = -.45, p = .19)., Conclusion: Programs have made different levels of commitment to service integration or teen friendliness policies. Lessons learned through the integration of sexually transmitted disease (STD) and family planning services may assist efforts to better integrate HIV services for adolescents. Further work to elucidate the relationship between integration and teen friendliness is needed. Periodic reviews can ensure that recommended clinical guidelines, specifically annual risk assessment, are being met, as well as identifying achievable next steps to improve adolescent sexual and reproductive health service delivery.

Syphilis has re-emerged in the United States and elsewhere, and clinicians caring for HIV-infected patients are challenged with syphilis diagnosis and management decisions. HIV alters the natural history of syphilis to an extent that is poorly understood, and initial presentation may be more varied in coinfected patients. Although commonly available diagnostic assays for syphilis should be interpreted as usual, such tests rely on antibody measurement and may be an imperfect indicator of active infection. Assessment of all available clinical and risk behavior data remains critically important in the diagnosis of syphilis in coinfected patients. Treatment of syphilis in such patients requires stage-appropriate therapy, with careful serologic monitoring to assess response. Clinicians must have heightened appreciation of the role of frequent risk assessment, serologic screening, symptom recognition, and follow-up of treated patients, as well as an understanding of public health functions such as sex partner treatment and communicable disease reporting.

Background: Chlamydia trachomatis-infected female teenagers with older partners may be less likely to discuss the infection with their partner(s) and to use condoms and therefore may be more likely to get reinfected., Goal: To determine if C trachomatis-infected female teenagers with older partners were more likely to be reinfected than those with same-aged partners., Study Design: Females aged 14 years to 18 years who had uncomplicated chlamydial infection, were nonpregnant, attended clinics in five United States cities from June 1995 to May 1997, completed treatment, and resumed sexual activity were observed at 1 and 4 months for interim history and retesting., Results: Of 225 women studied, 73.3% were black, 34.5% had at least one partner who was 3 or more years older during follow-up, 51.6% reported using a condom at the last sex act with all partners, 13.8% had a recurrent infection, and 47.4% reported they were certain that all of their baseline partners were treated. Partner age was not associated with condom use, certainty of partners' taking medication, or recurrent infections after adjustment for visit., Conclusions: Older partners, accounting for approximately one third of all partners, did not increase the risk of reinfection. Given the high risk for recurrence, follow-up testing and enhanced efforts to ensure partner treatment are appropriate for all young women with chlamydial infections.

Project RESPECT was a multisite randomized trial comparing three clinic-based interventions' ability to increase condom use and prevent infection with HIV and sexually transmitted diseases. Because Project RESPECT had guiding concepts that determined the content of the sessions, the authors investigated how the intervention operated using these theoretical variables. Growth curve analysis and structural equation modeling estimated the correlation between intentions toward condom use and self-reports of condom use and isolated the treatment effects on mediating variables--attitudes, self-efficacy, and social norms--that predict intentions. The correlations between intentions and behavior exceeded .70 for both genders, justifying the emphasis on intentions. Project RESPECT was effective through changing attitudes and self-efficacy for females in both counseling interventions. For males, only enhanced counseling had significant effects on these two mediator variables.

Background: Sequelae of genital Chlamydia trachomatis infection in women are more strongly linked to repeat infections than to initial ones, and persistent or subsequent infections foster continued transmission., Objective: To identify factors associated with persistent and recurrent chlamydial infection in young women that might influence prevention strategies., Methods: Teenage and young adult women with uncomplicated C trachomatis infection attending reproductive health, sexually transmitted disease, and adolescent medicine clinics in five US cities were recruited to a cohort study. Persistent or recurrent chlamydial infection was detected by ligase chain reaction (LCR) testing of urine 1 month and 4 months after treatment., Results: Among 1,194 women treated for chlamydial infection, 792 (66.4%) returned for the first follow-up visit, 50 (6.3 %) of whom had positive LCR results. At that visit, women who resumed sex since treatment were more likely to have chlamydial infection (relative risk [RR], 2.0; 95% CI, 1.03-3.9), as were those who did not complete treatment (RR, 3.4; 95% CI, 1.6-7.3). Among women who tested negative for C trachomatis at the first follow-up visit, 36 (7.1%) of 505 had positive results by LCR at the second follow-up visit. Reinfection at this visit was not clearly associated with having a new sex partner or other sexual behavior risks; new infection was likely due to resumption of sex with untreated partners. Overall, 13.4% of women had persistent infection or became reinfected after a median of 4.3 months, a rate of 33 infections per 1,000 person months., Conclusions: Persistent or recurrent infection is very common in young women with chlamydial infection. Improved strategies are needed to assure treatment of women's male sex partners. Rescreening, or retesting of women for chlamydial infection a few months after treatment, also is recommended as a routine chlamydia prevention strategy.

To study the structure of beliefs about condom use outcomes, the authors derived and tested 4 psychosocial hypothetical models: (a) a 2-factor model of the personal and social outcomes of condom use; (b) a 2-factor model of the pros and cons of the behavior; (c) a 3-factor model (i.e., physical, self-evaluative, and social) of outcome expectancies; and (d) a thematic 4-factor model of the protection, self-concept, pleasure, and interaction implications of the behavior. All 4 models were studied with a confirmatory factor analysis approach in a multisite study of 4,638 participants, and the thematic solution was consistently the most plausible. Self-concept and pleasure were most strongly associated with attitudes toward using condoms, intentions to use condoms, and actual condom use, whereas protection and interaction generally had little influence.

Objective: We sought to determine potential risk factors for upper genital tract inflammation in women with cervical Neisseria gonorrhoeae, Chlamydia trachomatis, or bacterial vaginosis., Study Design: In a case-controlled study we compared 111 women with cervical Neisseria gonorrhoeae, Chlamydia trachomatis, or bacterial vaginosis (the study group) with 24 women who had negative tests for each of these infections (the control group). We evaluated potential risk factors for upper genital tract inflammation by use of bivariate and then logistic regression analysis., Results: We found plasma cell endometritis in 53 of 111 women in the study group and 3 of 24 controls (odds ratio = 6.4, 95% confidence interval 1.7 to 35.0). On logistic regression, the study group women who were in the proliferative phase had increased likelihood of plasma cell endometritis (odds ratio = 4.5, 95% confidence interval 1.6 to 12.4)., Conclusion: The proliferative phase of the menstrual cycle seems to be the primary risk factor for ascending infection by organisms associated with pelvic inflammatory disease. This may be due to a hormonal effect or to the loss of the cervical barrier during menstruation.

To determine whether there were core groups of transmitters of gonorrhea and chlamydial infection among 14- to 35-year-olds in San Francisco during 1989-1993, sociodemographic risk factors for repeat gonorrhea and chlamydial infection were examined. During those 5 years, 8613 cases of gonorrhea were reported among males and 3893 among females; the proportions with repeat infection were 17.0% and 19.0%, respectively. There were also 2465 reported cases of chlamydial infection among males and 6996 among females; the proportions with repeat infection were 8.6% and 15.1%, respectively. Multivariate analyses reveal that for males, city planning region 5 was an independent risk factor for both repeat gonorrhea (relative hazard [RH] = 1.22; 95% confidence interval [CI] = 1.05-1.43) and repeat chlamydial infection (RH = 1.78; 95% CI = 1.23-2.57). For females, city planning region 4 was an independent risk factor for repeat gonorrhea (RH = 1.50; 95% CI = 1.12-1.98), and there was no high-risk planning region for repeat chlamydial infection. In San Francisco, there appear to be male and female core transmitters for gonorrhea but there may not be core transmitters for chlamydial infection.

Patient satisfaction is a valuable indicator of the quality of medical care. We assessed the impact of type of health insurance on satisfaction with seven aspects of medical care among 593 HIV-infected men without AIDS, drawn from three sites in San Francisco, California and Denver, Colorado. After adjustment for site of medical care, patient age, race, income, education, and CD4 lymphocyte count, there were few differences in satisfaction between men with fee-for-service and those with managed care insurance. Men with fee-for-service insurance were significantly more satisfied with their interpersonal relations with their clinicians (p = 0.01) but less satisfied with their finances (p = 0.0001) than persons with managed care. Uninsured men were significantly less satisfied with several aspects of care than insured persons. There were no significant differences in satisfaction between men with managed care and those with public insurance. HIV-infected persons who have a choice of insurance should carefully weigh their options, recognizing the implicit trade-offs between types of insurance. Those who choose fee-for-service insurance can expect to be more satisfied with interpersonal relations with their medical providers but less satisfied with financial aspects of their plans. Efforts to address the low satisfaction of uninsured persons are needed.

Depression is a serious, common, and treatable condition among HIV-infected persons. We examined the prevalence and predictors of depression and use of mental health services among 475 HIV-infected men without AIDS. Participants were drawn from three sites in San Francisco and Denver that did not provide ongoing medical care or mental health services. Depression was measured using the Center for Epidemiology Studies Depression scale (CES-D). Overall, 176 men (37.1%) were classified as depressed based on having a CES-D score above the standard cut-off of > or = 16. In logistic regression analysis, persons with HIV-related symptoms (OR = 3.4; 95% CI = 2.0.-5.6), low social support (OR = 2.5; 95% CI = 1.6-3.9), who were unemployed (OR = 1.9; 95% CI = 1.1-3.3), and with CD4 count < 200 cells (OR = 1.9; 95% CI = 1.1-3.3), were significantly more likely to be depressed. Only 40.3% of depressed men had seen a mental health clinician in the previous year and only 6.3% were taking an antidepressant. Among depressed men, in logistic regression analysis, men who were unemployed (OR = 2.4; 95% CI = 1.2-4.7) and those with health insurance (OR = 2.2; 95% CI = 1.1-4.5) were more likely to have received these services. Increased evaluation and treatment of HIV-infected persons for depression is needed.

This paper examines the effect of socioeconomic position on the differences in the 3-year rates (1990 to 1992) of reported cases of gonorrhea and chlamydia between Black and White adolescents, aged 12 to 20 years, residing in San Francisco. The crude relative risks for Blacks were 23.4 (95% confidence interval [CI] = 20.4, 27.8) for gonorrhea and 9.3 (95% CI = 8.3, 10.3) for chlamydia. Adjusting for poverty and occupational status, the relative risks were 28.7 (95% CI = 22.5, 36.1) for gonorrhea and 8.9 (95% CI = 7.4, 10.6) for chlamydia. This study demonstrates that factors other than poverty and occupational status account for the racial/ethnic differences in the rates of gonorrhea and chlamydia among adolescents in San Francisco.

The authors analyzed temporal trends in human immunodeficiency virus (HIV) infection among men and women who visited the San Francisco municipal sexually transmitted disease clinic between 1989 and 1992, using blinded HIV seroprevalence data. Temporal changes in sexual behavior were evaluated by abstracting self-reported information on sexual behaviors from a random sample of charts of men who visited the clinic between 1990 and 1992. From 1989 to 1992, HIV seropositivity declined from 2.0% to 1.0% among women (p = 0.06) and from 18.9% to 12.0% (p < 0.001) among men. The percentage of patients who reported having anal intercourse in the previous year did not change significantly during the study period. The percentage of male patients who reported having vaginal intercourse during the previous year decreased from 82.9% to 78.6% (p < 0.05), and the percentage of male patients who reported engaging in receptive oral sex during the previous year increased from 24.0% to 41.6% (p < 0.001). The percentage of male patients who reported that they always used condoms increased from 31.8% to 49.2% for anal sex, from 8.7% to 19.5% for vaginal sex, and from 1.4% to 6.3% for oral sex (p < 0.05). Among patients visiting the sexually transmitted disease clinic, there was a steady and significant decline in HIV seroprevalence. The decline in HIV seroprevalence was accompanied by a significant trend toward safer sexual practices. However, by the end of the study period, less than half of the patients reported using condoms all of the time, which suggests that there is a need to expand behavioral interventions to focus on high-risk persons.

Although women bear the brunt of gonococcal infection-related morbidity, few large studies of gonorrhea treatment in women have been conducted. In a multicenter, double-blind, placebo-controlled trial, 181 evaluable women with uncomplicated gonorrhea were treated with ciprofloxacin (250 mg orally; 94 women) or ceftriaxone (250 mg intramuscularly; 87 women). Twenty-four percent of the participants were infected with antibiotic-resistant Neisseria gonorrhoeae. Cervical gonorrhea was cured in 100% (93 of 93) of the women treated with ciprofloxacin and 99% (83 of 84) receiving ceftriaxone. All pharyngeal (n = 5) or rectal (n = 20) infections treated with ciprofloxacin were cured, as were ceftriaxone-treated patients with pharyngeal (n = 6) or rectal (n = 21) infection. Geometric mean MICs (range) for 248 pretreatment isolates were: penicillin, 0.28 (0.015 to 8.0); tetracycline, 0.46 (0.06 to 4); ciprofloxacin, 0.003 (0.002 to 0.015); and ceftriaxone, 0.004 (0.001 to 0.125) microgram/ml. Both drugs were well tolerated. Despite the high prevalence of antibiotic-resistant gonococci in these populations, 250 mg of oral ciprofloxacin was as effective as an injection of ceftriaxone.

Restriction fragment length polymorphism (RFLP) and plasmid analyses were used to evaluate an outbreak of Haemophilus ducreyi in San Francisco. Fifty-four cases of culture-confirmed chancroid occurred between May 1989 and May 1991. Of these, 46 (96%) were in men and 35 (65%) were in blacks; the median age of patients was 34 years. Among the 32 isolates submitted for RFLP and plasmid analyses, six different HindIII RFLP patterns were identified. Two RFLP types were found in patients who had recently traveled to Los Angeles, Korea, or El Salvador. Four RFLP types appeared to be acquired locally and were more common among blacks (P = .002), in patients with a history of a sexually transmitted disease (P = .01), and in those who used drugs or exchanged drugs or money for sex (P = .08). The use of RFLP analysis confirmed that this outbreak was associated with multiple strains of H. ducreyi and allowed for the identification of risk factors for locally acquired chancroid.

To compare the seroprevalence of and risk factors for human immunodeficiency virus infection (HIV) among patients attending a public sexually transmitted disease clinic, the authors conducted both voluntary and blinded seroprevalence surveys between June 1989 and August 1990. For the voluntary survey, every twenty-fifth patient attending the clinic for a new problem was invited to receive anonymous testing for HIV antibody. For the blinded survey, sera obtained for syphilis serologies from 2,297 (86%) of the 2,682 patients attending the clinic for a new problem were tested for HIV antibody after all personal identifiers were removed. Of the 946 eligible patients, 631 (66.7%) agreed to participate in the voluntary survey. Black men were significantly less likely to participate than other men and women (p < 0.0001). The prevalence of HIV antibody was 25% greater in the blinded survey than in the voluntary survey (15.2% and 11.4%, respectively, p < 0.05). This difference was due primarily to black homosexual/bisexual men, who had a 12.7-fold greater risk of HIV infection in the blinded survey than in the voluntary survey. These results suggest that blinded seroprevalence surveys may provide a better prevalence estimate of HIV infection than voluntary surveys. The greater risk for HIV infection observed among homosexual and bisexual black men, who were tested only in the blinded serosurvey, suggests that efforts to increase voluntary testing for HIV infection in this group should be developed.

Portions of sub-Saharan Africa are subject to major epidemics of meningococcal meningitis that require early detection and rapid control. We evaluated the usefulness of weekly meningitis rates derived from active surveillance data in Burkina Faso for detecting a meningitis epidemic. By analysing the rates of disease in 40 x 40km2 areas within a study region of Burkina Faso, we found that a threshold of 15 cases/100,000/week averaged over 2 weeks was 72-93% sensitive and 92-100% specific in detecting epidemics exceeding 100 cases/100,000/year. During epidemic periods, the positive predictive value of this threshold approached 100% for detecting local epidemics. Additionally, meningitis incidence was proportional to village size, with villages greater than 8000 having the highest disease rates during a major group A meningococcal epidemic in 1983-1984. Despite the rudimentary nature of surveillance data available in many developing countries, these data can be used to detect the early emergence of meningitis epidemics. Additional studies are needed to determine the relevance of this approach for detecting epidemics.

In contrast to rates for the United States as a whole, the incidence rate of gonorrhea increased 11% in San Francisco between 1986 and 1988, with substantial increases observed among black adolescents. Reports by health department personnel and police suggested that crack cocaine use, specifically the exchange of sex for drugs, contributed to this increase. To test this hypothesis, the authors conducted a case-control study from August 1988 to October 1988 that compared 68 prospectively identified adolescent gonorrhea patients with 136 neighborhood control patients. Thirty-two percent of the female gonorrhea patients had received money or drugs in exchange for sex, while none of the control patients reported having done so (P = 0.0001). Most of the female patients (89%) who had received money or drugs in exchange for sex had used crack. Crack use was less common among female patients who denied receiving money or drugs in exchange for sex (11%) and among control patients (6%). Crack use and providing money or drugs in exchange for sex were not risk factors for gonorrhea among the male patients, but were reported frequently by both gonorrhea patients and control patients. Not living with parents was a risk factor for male patients (odds ratio 4.9, 95% confidence limit 1.4 to 19.5). For all patients, a history of a sexually transmitted disease appeared to be an independent risk factor for gonorrhea. The conclusion is made that crack-related exchange of sex for money or drugs is a risk factor for gonorrhea among black adolescent girls in San Francisco.(ABSTRACT TRUNCATED AT 250 WORDS)

Chlamydia trachomatis is the most prevalent sexually transmitted bacterial pathogen. Nevertheless, selective, rather than universal, screening for chlamydia has been recommended, largely because testing is expensive and requires considerable technical expertise. A total of 1,348 women in four family planning clinics in San Francisco, California, were screened from March 1987 to January 1988 to identify criteria for selective screening. Of these, 9.2% had a positive chlamydia test using direct fluorescence. Logistic regression analysis identified five factors associated with infection: age less than 25 years, cervical friability, single marital status, a new sexual partner within the past 3 months, and lack of barrier contraceptive use. No single risk factor or combination of risk factors had both a high sensitivity and a high positive predictive value for infection. While screening all women who were unmarried would detect 93% of those with chlamydia, the positive predictive value of 10.7% was not much higher than the overall prevalence. Conversely, screening all women with cervical friability, which had a positive predictive value of 23.2%, would only detect 11% of those with chlamydia. On the basis of the authors' findings, selective screening should not be used in high prevalence populations in which all women are at risk and should be screened for chlamydia.

Sequential case-control studies were used to monitor changes in the clinical protection induced by group A meningococcal polysaccharide vaccine over a 3-year period. Overall, vaccine efficacy declined from 87% 1 year after vaccination to 70% and 54% at 2 and 3 years, respectively. When stratified by age at time of vaccination the data showed that, although vaccine efficacy remained high in children greater than or equal to 4 years of age (vaccine efficacy 85%, 74%, and 67% at 1, 2, and 3 years after vaccination, respectively), it declined dramatically in those less than 4 years of age at time of vaccination (vaccine efficacy 100%, 52%, and 8%, respectively, at 1, 2, and 3 years after vaccination). Thus, a single dose of group A meningococcal vaccine does not yield lasting clinical protection in children less than 4 years of age.

The validity of commercial latex agglutination kits for detection of Haemophilus influenzae type b and Streptococcus pneumoniae antigens in serum and urine specimens was studied. We tested serum and urine specimens from 44 patients with bacteremic pneumonia (23 S. pneumoniae, 13 H. influenzae type b, 11 other) with commercial latex agglutination kits (Directigen, Bactigen) for S. pneumoniae and H. influenzae type b antigens. All specimen samples were randomized and read blindly by two readers. Interreader reproducibility was 100%. The sensitivity and specificity of both kits for H. influenzae type b antigens in serum and urine were greater than 90%. None of the 24 urine samples from S. pneumoniae bacteremic patients were positive by either kit, although 6 ng of type 3 polysaccharide could be detected in spiked urine. Sensitivity for S. pneumoniae antigens in serum was 27% for Directigen and 38% for Bactigen. Specificity for S. pneumoniae antigens in serum was 95% for Directigen and 74% for Bactigen. The results suggest that the kits are useful in diagnosing H. influenzae type b pneumonia. However, the commercially available S. pneumoniae reagents tested appear to have limited utility for diagnosing S. pneumoniae pneumonia because both kits lack sensitivity and Bactigen lacks specificity, as well.

Infection of hemodialysis patients with nontuberculous mycobacteria (NTM) has been associated with water used in reprocessing hemodialyzers. This study was conducted to determine the prevalence of NTM and other bacteria in water samples collected over a 13-week period from 115 randomly selected dialysis centers in the United States. Total viable counts were determined by membrane filter assays; increased recovery of NTM was obtained by dosing a portion of each water sample with 1% formaldehyde (HCHO) before filtering. NTM were widely distributed and occurred with a high frequency in water supplies in dialysis centers. NTM were detected in water from 95 centers (83%), and 50% of all samples examined contained NTM. The results of this study support recommendations to use 4% HCHO or a chemical germicidal equivalent for disinfecting dialyzers that are to be reused.