Cefazolin versus Nafcillin for Methicillin-Sensitive Staphylococcus aureus Bloodstream Infection in a California Tertiary Medical Center.

Recent observational studies have suggested possible reductions in mortality in patients receiving cefazolin versus antistaphylococcal penicillins. We examined 90-day mortality in patients receiving cefazolin compared to nafcillin for methicillin-susceptible Staphylococcus aureus (MSSA) bloodstream infection (BSI). We identified persons with MSSA BSI admitted to San Francisco General Hospital from January 2008 to July 2013 through a hospital-wide infection surveillance system and confirmed 90-day mortality using U.S. national vital registries. We included persons receiving cefazolin or nafcillin as the predominant intravenous antimicrobial agent; all participants received inpatient Infectious Diseases service consultation. We estimated the association between receipt of cefazolin and 90-day risk of death by multivariate logistic regression, including a propensity score for receiving cefazolin as the second predictor. Of 230 MSSA BSI cases, 30 received nafcillin and 70 received cefazolin as the predominant antimicrobial; 10 died within 90 days, 5 from each group. Unadjusted analysis showed substantial but not statistically significant reduced odds of death in those receiving cefazolin (odds ratio, 0.38; 95% confidence interval [CI], 0.10 to 1.44). Multivariate analysis with propensity scores found a similar adjusted odds ratio (0.40; 95% CI, 0.09 to 1.74; P = 0.22). We found a large reduction in 90-day mortality in those receiving cefazolin compared to nafcillin for MSSA BSI, but this finding was not statistically significant. The magnitude of effect seen in this and other studies justifies further study.

Transmission of GB virus type C via transfusion in a cohort of HIV-infected patients.

BACKGROUND: GB virus C (GBV-C) infection is transmitted by blood exposure and associated with lower human immunodeficiency virus (HIV) load and slower HIV disease progression. Few studies describe predictors of acute GBV-C infection following transfusion in HIV-infected patients. METHODS: We used a limited-access database from the National Heart Lung and Blood Institute's Viral Activation Transfusion Study, a randomized controlled trial of leukoreduced versus nonleukoreduced transfusions received by HIV-infected, transfusion-naive patients. Blood samples from 489 subjects were tested for GBV-C markers in pretransfusion and posttransfusion samples. We estimated the risk of acquiring GBV-C RNA and predictors of GBV-C acquisition, using pooled logistic regression. RESULTS: GBV-C RNA was detected ≤120 days following the first transfusion in 22 (7.5%) of 294 subjects who were GBV-C negative before transfusion. The risk of GBV-C RNA acquisition increased with each unit transfused (odds ratio, 1.09; 95% confidence interval, 1.06-1.11). Lower baseline HIV load and use of antiretroviral therapy were associated with subsequent GBV-C RNA acquisition, after control for units of blood transfused. Leukoreduced status of transfused units was not associated with GBV-C transmission. CONCLUSIONS: Blood transfusion is associated with a significant risk of GBV-C acquisition among HIV-infected patients. Transmission of GBV-C by blood transfusion was inversely related to HIV load.

Development of a low-cost system for measuring conditional time-averaged gradients of SO2 and NH3.

A conditional time-averaged gradient (COTAG) system has been developed to provide direct long-term (weekly to monthly) average flux gradient measurements for a range of trace gases, between land and atmosphere. Over daily periods, atmospheric conditions can range from high stability, where the vertical gradients of ambient concentration are enhanced due to very small diffusivity, to highly unstable conditions, in which concentration gradients are small due to the intense turbulent activity of the surface layer. The large vertical gradients generated by high stability would bias the estimate of the actual flux: to avoid this, the COTAG system samples conditionally, within a carefully refined range of stability. A comparison with a continuous flux gradient system suggested that the removal of stable conditions from the sampling period does not substantially modify the evaluation of the long-term fluxes.

A model-based estimate of the mean incubation period for AIDS in homosexual men.

Because of the difficulty in identifying the date of exposure to type 1 of the human immunodeficiency virus (HIV-1) infection in persons other than transfusion recipients, studies of the incubation periods for acquired immunodeficiency syndrome (AIDS) have been limited. When data from a cohort of 84 homosexual and bisexual men that provided the information to determine the years of conversion of sera infected with HIV-1 were analyzed, a model for the proportion likely to develop AIDS and the incubation period for AIDS in homosexual men could be derived. The maximum likelihood estimate for the proportion of infected homosexual men developing AIDS is 0.99 (90% confidence interval ranging from 0.38 to 1). Furthermore, the maximum likelihood estimate for the mean incubation period for AIDS in homosexual men is 7.8 years (90% confidence interval ranging from 4.2 years to 15.0 years), which is close to the estimate of 8.2 years for adults developing transfusion-associated AIDS.

A simple screening tool for active tuberculosis in HIV-infected adults receiving antiretroviral treatment in Uganda.

SETTING: Reliable clinical algorithms that screen for active tuberculosis (TB) in human immunodeficiency virus (HIV) infected people initiating or receiving antiretroviral treatment (ART) in sub-Saharan Africa could reduce the need for diagnostic procedures. METHODS: We estimated the utility of six TB-related signs and symptoms, alone or in combination, compared with the Uganda Ministry of Health diagnostic guidelines for participants with prevalent (baseline), early ART (< or = 3 months on ART) and incident TB (>3 months on ART). RESULTS: Of 1995 participants screened for ART eligibility, 71 (3.6%) had prevalent TB. The presence of any one of the following: cough > or = 3 weeks, fever > or = 4 weeks, lymphadenopathy or baseline body mass index < or = 18 kg/m(2) had a sensitivity of 99% (95%CI 96-100), a specificity of 66% (95%CI 64-68) and a negative predictive value (NPV) of 100% (95%CI 99-100) for predicting active TB. During ART follow-up, TB incidence was 2.4 (95%CI 1.6-3.4)/100 person-years. The presence of cough > or = 3 weeks or general weakness was 100% sensitive (95%CI 99-100), 66% specific (95%CI 59-74) and had an NPV of 100% (95%CI 99-100). CONCLUSION: Use of a simple TB screening algorithm can accurately identify, in a resource-poor African setting, HIV-infected individuals who require further procedures to diagnose active TB.

Antiretroviral regimens for patients with HIV who fail first-line antiretroviral therapy.

BACKGROUND: Highly active antiretroviral therapy has reduced the morbidity and mortality of patients with HIV/AIDS. A common first-line ART regimen includes a non-nucleoside reverse transcriptase inhibitor (NNRTI) and two nucleoside reverse transcriptase inhibitors (NRTIs). If treatment failure occurs, a change to second-line therapy is necessary. OBJECTIVES: This meta-analysis aimed to assess the optimum antiretroviral regimen for patients with HIV who fail first-line therapy (ART-naive) with d4T+3TC+NVP; d4T+3TC+EFV; ZDV+3TC+NVP; and ZDV+3TC+EFV. SEARCH STRATEGY: Electronic databases and conference proceedings were searched with relevant search terms without limits to language. SELECTION CRITERIA: Randomised controlled trials of HIV-infected adult patients administered second-line ART after virologic failure of a first-line regimen were included. The primary outcome measure included the proportion of patients achieving undetectable plasma HIV RNA concentration (viral load). Secondary outcome measures included change in mean CD4 cell count, clinical resolution of symptoms, rate of adverse events, rate of change in therapy for failure, rate of change in therapy for toxicity, and mortality. DATA COLLECTION AND ANALYSIS: Two authors assessed each reference for inclusion and exclusion criteria established a priori. Data were abstracted independently using a standardised abstraction form. MAIN RESULTS: Twenty-one records were identified in total, 6 of which were duplicates. None of the records met inclusion criteria. AUTHORS' CONCLUSIONS: There is insufficient evidence to evaluate second-line therapies in patients with HIV who fail first-line treatment with d4T+3TC+NVP; d4T+3TC+EFV; ZDV+3TC+NVP; and ZDV+3TC+EFV. Current recommendations are based on available resources and results from individualised treatment decisions based on resistance testing and clinician choice.

Antiretroviral post-exposure prophylaxis (PEP) for occupational HIV exposure.

BACKGROUND: Populations such as healthcare workers (HCWs), injection drug users (IDUs), and people engaging in unprotected sex are all at risk of being infected with the human immunodeficiency virus (HIV). Animal models show that after initial exposure, HIV replicates within dendritic cells of the skin and mucosa before spreading through lymphatic vessels and developing into a systemic infection (CDC 2001). This delay in systemic spread leaves a "window of opportunity" for post-exposure prophylaxis (PEP) using antiretroviral drugs designed to block replication of HIV (CDC 2001). PEP aims to inhibit the replication of the initial inoculum of virus and thereby prevent establishment of chronic HIV infection. OBJECTIVES: To evaluate the effects of antiretroviral PEP post-occupational exposure to HIV. SEARCH STRATEGY: The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, AIDSearch, and the Database of Abstracts of Reviews of Effectiveness were searched from 1985 to January 2005 to identify controlled trials. There were no language restrictions. Because no controlled clinical trials were retrieved, the search was repeated on 31 May 2005 in MEDLINE, AIDSearch and EMBASE using a search strategy to identify analytic observational studies. Handsearches of the reference lists of all pertinent reviews and studies found were also undertaken. Experts in the field of HIV prevention were contacted. SELECTION CRITERIA: Types of studies: All controlled trials (including randomized clinical trials and controlled clinical trials). If no controlled trials were found, analytic studies (e.g. cohort and case-control studies) were considered. Descriptive studies (i.e. studies with no comparison groups) were excluded. Types of participants included:HCWs exposed to any known or potentially HIV contaminated product;anyone exposed to a needlestick contaminated by known or potentially HIV-infected blood or other bodily fluid in an occupational setting; andanyone exposed through the mucous membranes to an HIV-infected or potentially infected substance in occupational setting.Excluded: Sex workers (PEP post-sexual exposure is addressed in another Cochrane review (Martín 2005)). Types of interventions: Any intervention that administered single or combinations of antiretrovirals as PEP to people exposed to HIV through percutaneous injuries and/or occupational mucous membrane exposures when the HIV status of the source patient was positive or unknown. Studies comparing two types of PEP regimens were considered, as were studies comparing PEP with no intervention. Types of outcome measures:Incidence of HIV infection in those given PEP versus those given placebo or a different PEP regimen; Adherence to PEP; Complications of PEPTypes of outcome measures: Incidence of HIV infection in those given PEP versus those given placebo or a different PEP regimen; Adherence to PEP; Complications of PEP DATA COLLECTION AND ANALYSIS: Data concerning outcomes, details of the interventions, and other study characteristics were extracted by two independent authors (TY and JA) using a standardized data extraction form (Table 04). A third author (GK) resolved disagreements. The following information was gathered from each included study: location of study, date, publication status, demographics (e.g. age, gender, occupation, risk behavior, etc.) of participants/exposure modality, form of PEP used, duration of use, and outcomes. Odds ratios with a 95% confidence interval (CI) were used as the measure of effect. A meta-analysis was performed for adverse events where two-drug regimens were compared with three-drug regimens. Due to overlap between Puro 2000 and Puro 2005, the former was not included in the combined analysis. MAIN RESULTS: Effect of PEP on HIV seroconversionNo randomized controlled trials were identified. Only one case-control study was included. HIV transmission was significantly associated with deep injury (OR 15, 95% CI 6.0 to 41), visible blood on the device (OR 6.2, 95% CI 2.2 to 21), procedures involving a needle placed in the source patient's blood vessel (OR 4.3, 95% CI 1.7 to 12), and terminal illness in the source patient (OR 5.6, 95% CI 2.0 to 16). After controlling for these risk factors, no differences were detected in the rates at which cases and controls were offered post-exposure prophylaxis with zidovudine. However, cases had significantly lower odds of having taken zidovudine after exposure compared to controls (OR 0.19, 95%CI 0.06 to 0.52). No studies were found that evaluated the effect of two or more antiretroviral drugs for occupational PEP. Adherence to and complications with PEPEight reports from observational comparative studies confirmed findings that adverse events were higher with a three-drug regimen, especially one containing indinavir. However, discontinuation rates were not significantly different. AUTHORS' CONCLUSIONS: The use of occupational PEP is based on limited direct evidence of effect. However, it is highly unlikely that a definitive placebo-controlled trial will ever be conducted, and, therefore, on the basis of results from a single case-control study, a four-week regimen of PEP should be initiated as soon as possible after exposure, depending on the risk of seroconversion. There is no direct evidence to support the use of multi-drug antiretroviral regimens following occupational exposure to HIV. However, due to the success of combination therapies in treating HIV-infected individuals, a combination of antiretroviral drugs should be used for PEP. Healthcare workers should be counseled about expected adverse events and the strategies for managing these. They should also be advised that PEP is not 100% effective in preventing HIV seroconversion. A randomized controlled clinical trial is neither ethical nor practical. Due to the low risk of HIV seroconversion, a very large sample size would be required to have enough power to show an effect. More rigorous evaluation of adverse events, especially in the developing world, are required. Seeing that current practice is partly based on results from individual primary animal studies, we recommend a formal systematic review of all relevant animal studies.

Stavudine, lamivudine and nevirapine combination therapy for treatment of HIV infection and AIDS in adults.

BACKGROUND: A favourable regimen for people infected with HIV/AIDS is one that provides optimal efficacy, durability of antiretroviral activity, tolerability, and has low adverse effects and drug-drug interactions. The combination of the non-nucleoside reverse transcriptase inhibitor nevirapine (NVP), and two nucleoside reverse transcriptase inhibitors, stavudine (d4T) and lamivudine (3TC), is widely used as first-line therapy, especially in low-resource countries. Analysis of the efficacy, durability and tolerability of the regimen is thus important to clinicians, consumers and policy-makers living in both rich and poor countries. OBJECTIVES: To examine the efficacy of the stavudine, lamivudine and nevirapine regimen for the treatment of HIV infection and AIDS in adults. SEARCH STRATEGY: We used the comprehensive search strategy developed specifically by the Cochrane HIV/AIDS Review Group to identify HIV/AIDS randomised controlled trials, and searched the following electronic databases: MEDLINE (searched July 2004); Embase (searched October 2004); and CENTRAL (July 2004). This search was supplemented with a search of AIDSearch (April 2005) to identify relevant conference abstracts, as well as searching reference lists of all eligible articles. The search was not limited by language or publication status. SELECTION CRITERIA: Randomised controlled trials of the stavudine, lamivudine and nevirapine regimen, compared with any other regimens for treating HIV/AIDS, in antiretroviral treatment-naive or antiretroviral treatment-experienced adults. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed the methodological quality of the trials and extracted data. MAIN RESULTS: Our search resulted in 1,148 records, of which two studies described trials that met our inclusion criteria. One trial was a small single-centre Australian trial of 70 antiretroviral-naive participants, while the other trial was a large, multicentre trial, conducted in 14 countries, of 1,216 antiretroviral-naive participants. In both trials over 60% of participants were male. As the therapeutic combinations compared in both trials were not identical, it was not possible to conduct a meta-analysis to increase the power of the results. The main findings, therefore, are from the much larger trial, which was of a high quality. This trial found that there was no statistically significant difference in the efficacy (measured by treatment failure) between nevirapine and efavirenz (EFZ), when used in combination with 3TC and d4T (RR = 1.16; 95%CI: 0.95, 1.41). There was no statistically significant difference between once daily or twice-daily dosing of NVP, when used in combination with 3TC and d4T (RR = 1.00; 95%CI: 0.83; 1.21). It also showed that, compared with NVP plus EFZ, 3TC and d4T, a once-daily dosing of NVP, in combination with 3TC and d4T, performs better in averting treatment failure (RR = 0.82; 95%CI: 0.67, 1.00) than does twice-daily dosing of NVP with 3TC and d4T (RR = 0.82; 95%CI: 0.69; 0.97). Frequency of toxicity was higher in participants receiving NVP, compared with EFZ. AUTHORS' CONCLUSIONS: The combination of nevirapine, 3TC and d4T is as efficacious as a combination of efavirenz, 3TC and d4T. Once-daily NVP with twice-daily 3TC and d4T is as efficacious as twice-daily NVP, 3TC and d4T. However, toxicity may be increased in the once-daily NVP regime. Additional trials of sufficient duration are required to provide better evidence for the use of this combination as a first line therapy. Ideally, trials should use standardised assessment measures especially with respect to measuring viral load, so that results can be compared and combined in meta-analyses.

A cylindrically symmetric "micro-Mott" electron polarimeter.

A small, novel, cylindrically symmetric Mott electron polarimeter is described. The effective Sherman function, Seff, or analyzing power, for 20 kV Au target bias with a 1.3 keV energy loss window is 0.16 ± 0.01, where uncertainty in the measurement is due primarily to uncertainty in the incident electron polarization. For an energy loss window of 0.5 keV, Seff reaches its maximum value of 0.24 ± 0.02. The device's maximum efficiency, I/Io, defined as the detected count rate divided by the incident particle rate, is 3.7 ± 0.2 × 10(-4) at 20 keV. The figure-of-merit of the device, η, is defined as Seff (2)IIo and equals 9.0 ± 1.6 × 10(-6). Potential sources of false asymmetries due to detector electronic asymmetry and beam misalignment have been investigated. The new polarimeter's performance is compared to published results for similar compact retarding-field Mott polarimeters, and it is concluded that this device has a relatively large Seff and low efficiency. SIMION(®) electron trajectory simulations and Sherman function calculations are presented to explain the differences in performance between this device and previous designs. This design has an Seff that is insensitive to spatial beam fluctuations and, for an energy loss window >0.5 keV, negligible background due to spurious ion and X-ray production at the target.

Feasibility and effectiveness of a brief, intensive phylogenetics workshop in a middle-income country.

There is an increasing role for bioinformatic and phylogenetic analysis in tropical medicine research. However, scientists working in low- and middle-income regions may lack access to training opportunities in these methods. To help address this gap, a 5-day intensive bioinformatics workshop was offered in Lima, Peru. The syllabus is presented here for others who want to develop similar programs. To assess knowledge gained, a 20-point knowledge questionnaire was administered to participants (21 participants) before and after the workshop, covering topics on sequence quality control, alignment/formatting, database retrieval, models of evolution, sequence statistics, tree building, and results interpretation. Evolution/tree-building methods represented the lowest scoring domain at baseline and after the workshop. There was a considerable median gain in total knowledge scores (increase of 30%, p<0.001) with gains as high as 55%. A 5-day workshop model was effective in improving the pathogen-applied bioinformatics knowledge of scientists working in a middle-income country setting.

Antifungal interventions for the primary prevention of cryptococcal disease in adults with HIV.

BACKGROUND: Cryptococcal disease is an opportunistic infection that causes significant morbidity and mortality in adults with HIV. Primary prophylaxis with antifungal interventions may decrease cryptococcal disease incidence and associated mortality. OBJECTIVES: To assess the efficacy of antifungal interventions for the primary prevention of cryptococcal disease in adults with HIV. SEARCH STRATEGY: We searched the following databases: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), ClinicalTrials.gov, Database of Abstracts of Reviews of Effectiveness (DARE), Latin American and Caribbean Literature on the Health Sciences (LILACS), and the Cochrane Controlled Trials Register (CCTR). We reviewed abstracts from the following relevant conferences: International AIDS Conference, International AIDS Society Conference on HIV Pathogenesis and Treatment, and Conference on Retroviruses and Opportunistic Infections. We searched reference lists for all primary and other pertinent articles identified. We attempted to contact experts in the field, particularly primary authors of included studies, to better ensure completeness of included studies. We also approached pharmaceutical companies for any available and relevant unpublished data. The time period searched was from 1980 to August 2004. We placed no language restrictions on the search. Key words used include: meningitis, cryptococcal, cryptococcus, cryptococcosis, acquired immunodeficiency syndrome, human immunodeficiency virus, prophylaxis, chemoprevention, antifungal agents, and the Cochrane screen for randomized controlled trials. SELECTION CRITERIA: Randomized controlled trials using antifungal interventions for the primary prevention of cryptococcal disease in adults with HIV were selected. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial eligibility and quality. Trial authors, experts, and pharmaceutical companies were contacted for additional and/or missing information. Data were abstracted by two reviewers. Data were pooled, where appropriate, to yield summary estimates. MAIN RESULTS: Five studies (N=1316) were identified. All study patients had CD4 cell counts <300 cells/microl, and the majority of patients had CD4 cell counts <150 cells/microl. When all five studies are analyzed as a single group (N=1316), the incidence of cryptococcal disease was decreased in those taking primary prophylaxis (RR 0.21, 95% CI 0.09, 0.46) compared to those taking placebo. However, there was no significant difference in overall mortality observed (RR 1.01, 95% CI 0.71, 1.44). When the three studies using itraconazole as the intervention were analyzed together (N=798), the incidence of cryptococcal disease was decreased in those taking itraconazole for primary prophylaxis (RR 0.12, 95% CI 0.03, 0.51) compared to those taking placebo; however, there was no significant difference in overall mortality (RR 1.12, 95% CI 0.70, 1.80). When the two studies using fluconazole as the intervention were analyzed together (N=518), the incidence of cryptococcal disease was decreased in those taking fluconazole for primary prophylaxis (RR 0.25, 95% CI 0.07, 0.87) compared to those taking placebo; however, there was no significant difference in overall mortality (RR 0.59, 95% CI 0.14, 2.62). AUTHORS' CONCLUSIONS: Antifungal primary prophylaxis with either itraconazole or fluconazole is effective in reducing the incidence of cryptococcal disease in adults with advanced HIV disease. However, neither of these interventions has a clear effect on overall mortality. Further research is needed to better understand these interventions and the populations in which they may be most effective.

Evaluation of AIDS prevention and control programs.

PIP: To date, no full-scale community-based trials of acquired immunodeficiency syndrome (AIDS) prevention interventions with appropriate controls have been conducted and the true effect of such programs on the community-wide incidence of human immunodeficiency virus (HIV) infection cannot be measures. A review of the literature indicates, however, that some AIDS prevention programs are building in an evaluation component, including baseline studies and needs assessments, pre- and post-test measures of knowledge, attitude, and behavioral changes, and biomedical indicators of program-related effects such as HIV serostatus. The literature from the period July 1988-June 1989 reveals a trend toward interventions targeted at high-risk populations such as racial and ethnic minorities, prostitutes, prison inmates, substance abusers, and adolescents. Evaluations of programs aimed at specific populations commonly measure the impact of one or more types of interventions on the knowledge and practice of behaviors known to reduce the risk of HIV transmission. Programs that give participants the skills needed for the initiation and maintenance of risk-reduction behaviors appear to be more effective than programs emphasizing cognitive or affective learning alone. The literature confirms the benefits of use of indigenous health communicators in program planning and implementation and of a multi-faceted (e.g., mass media, community, and individual-level interventions) strategy.^ieng

The epidemiology of AIDS in Asian and Pacific Islander populations in San Francisco.

To evaluate the epidemiology of HIV infection in Asian and Pacific Islander populations in San Francisco, we compared cases of AIDS reported in Asians and Pacific Islanders with those reported in other racial and ethnic groups. The incidence of AIDS in Asians and Pacific Islanders was significantly lower than in Whites, Blacks, Latinos and American Indians and Alaska natives. AIDS cases among Asians and Pacific Islanders have increased 177% since 1985 compared with 54% in other racial and ethnic groups, with the greatest increase in homosexual and bisexual men and transfusion recipients. Among Asian and Pacific Islander ethnic groups, the incidence of AIDS was 168 cases per 100,000 in Polynesians, 141 per 100,000 in Japanese, 92 per 100,000 in 100 Filipinos, 72 per 100,000 in southeast Asians, and 21 per 100,000 in Chinese. We conclude that AIDS cases are disproportionately increasing in Asians and Pacific Islanders in San Francisco.

PIP: In Asia and in people of Asian and Pacific Islander ancestry in the United States, AIDS is a rare disease. San Francisco, with the highest incidence of AIDS in the United States, also has the highest percentage (21%) of Asians and Pacific Islanders. To understand the potential for AIDS in this select population, trends over time and the demographics of reported AIDS cases among the select population in San Francisco were analyzed. Records were reviewed of AIDS cases reported to the San Francisco Department of Health, which had a substantiated 98% report rate. As of March 31,1988, 83 (1.8%) of the 4689 cases and 42 (1.5%) of the 2831 deaths reported were among the select population. The incidence of AIDS among the select population (58.5/100,000) was significantly lower than among whites (1108.8/100,000), blacks (368.9/100,000), and latinos (421.0/100,000). Among the select population, however, AIDS increased more rapidly since 1985 than among the whites, blacks, or latinos. Of the 83 cases reported, 69 were homosexual or bisexual men without intravenous drug use, 3 homosexual or bisexual men with histories of intravenous drug use, 6 were transfusion recipients, 3 were heterosexual intravenous drug users, 1 was a heterosexual contact of a person at risk for AIDS, and 1 was a hemophiliac. Comparison of transmission categories of the select population with those of the other racial and ethnic groups showed a significantly greater (P 0.001) number of transfusion recipients and a significantly lower (P 0.02) number of homosexual and bisexual intravenous drug users. The greatest increase in cases among the select population was in homosexual and bisexual men without histories of intravenous drug use, which was greater than the increase among nonAsian or Pacific Islander homosexual and bisexual men (P 0.10). These findings support the theory that HIV entered the select population communities later than it did nonAsian or Pacific Islander communities.

Effect of the revised AIDS case definition on AIDS reporting in San Francisco: evidence of increased reporting in intravenous drug users.

To examine the effect of the revision of the US national AIDS case definition in September 1987, we compared demographic and clinical information for AIDS patients diagnosed and reported to the San Francisco Department of Public Health between 1 September 1987 and 31 October 1989. Of the 3167 patients diagnosed and reported during the study period, 584 (18%) met the revised case definition only, increasing AIDS case reporting in San Francisco by 23%. One hundred and thirty-four of these 584 patients (23%) subsequently developed diagnoses meeting the old definition. After adjusting for this proportion, the revised case definition increased reporting by 17%. The mean time between initial diagnosis with a disease meeting the revised definition and subsequent development of a disease meeting the old definition was 18.5 months. Patients who met the revised case definition only were slightly older and more likely to be Black, female, and intravenous drug users (IVDUs) than those meeting the old case definition. The majority of patients who met the revised case definition only had initial diagnoses of HIV wasting syndrome (26%), HIV encephalopathy (21%), and presumptive Pneumocystis carinii pneumonia (19%). The revised AIDS case definition has significantly increased the reporting of severe morbidity associated with HIV infection, particularly among IVDUs.

Determinants of survival in adult Brazilian AIDS patients, 1982-1989. The Brazilian State AIDS Program Co-Ordinators.

OBJECTIVE: Little has been published about the length and determinants of survival for persons with AIDS in developing countries. This study examined the survival experience of Brazilian AIDS patients from 1982 to 1989. DESIGN: A retrospective cohort study involving record review of reported AIDS cases. METHODS: We obtained information about 2135 adult AIDS patients in Brazil. Local health officials supplied data regarding demographic and clinical characteristics and length of survival. Statistical techniques of survival analysis were applied. RESULTS: Median survival was 5.1 months, much shorter than in developed countries, and there was no improvement in survival for cases diagnosed more recently. Younger patients and those in the intravenous drug use exposure category lived longer than other AIDS patients. Those presenting with Kaposi's sarcoma, esophageal candidiasis, and tuberculosis fared relatively well, while those presenting with multiple diagnoses or toxoplasmosis did more poorly. CONCLUSIONS: These results tend to confirm the predictors of AIDS survival previously reported from developed countries and to document the poor survival of AIDS patients in the developing world.

Truck drivers in Brazil: prevalence of HIV and other sexually transmitted diseases, risk behavior and potential for spread of infection.

OBJECTIVES: To determine the prevalence of HIV and syphilis and related risk behavior in a sample of truck drivers in Santos, Brazil. SUBJECTS AND METHODS: A cross-sectional study was performed of 300 male truck drivers recruited in the port of Santos, Brazil, including a face-to-face interview and blood sampling for HIV and syphilis serology. RESULTS: Of 300 subjects, 4 (1.3%) were positive for HIV, 25 (8.3%) for syphilis by the Venereal Disease Research Laboratory (VDRL) test and 38 (13%) were positive for syphilis by the fluorescent treponemal antibody (absorbed) test (FTA-Abs). Seventy-one per cent had been employed as truck drivers for more than 10 years and 93% lived outside of Santos. Most participants were married (72%); 40% reported having more than one sex partner; 21% reported sex with commercial sex workers; 14% reported sex with girls that they met on the road; 16% had sex with other men's wives; and 3.3% reported sex with men during the past year. The use of rebite, an oral stimulant, was reported by 43% and was associated with being FTA-Abs-positive (P = 0.04). Being HIV-positive was associated with having sex with friends (P = 0.04), partners usually considered 'safe' by truck drivers. Being syphilis-positive (VDRL) was significantly associated with sex with partners also considered as 'safe', namely primary sex partners, steady partners and other men's wives. DISCUSSION: This is the first study to determine HIV and syphilis seroprevalence among truck drivers in South America. Findings confirm that this group has a high potential risk for HIV infection and other sexually transmitted diseases, and thus currently presents an opportunity for prevention.

Estimating AIDS infection rates in the San Francisco cohort.

Between 1978 and 1980 a cohort of approximately 6700 homosexual and bisexual men were recruited from the San Francisco City Clinic to participate in studies of sexually transmitted hepatitis B. Testing frozen blood specimens collected at intervals from these patients provides a means of tracking the spread of the AIDS virus since 1978. The rate of spread of HIV was estimated by fitting different survival curves to interval-censored serological data using maximum likelihood techniques. The curves were compared using the Akaike Information Criterion (AIC) to select that which best describes the data. The best was found to be a log-logistic model, which suggested that between 1978 and 1981 the virus spread rapidly, infecting 44% of the then uninfected cohort members. More recently the rate of spread has declined, with an additional 32% of the cohort becoming infected between 1981 and 1987.

Survival following diagnosis of Kaposi's sarcoma for AIDS patients in San Francisco.

To evaluate survival for AIDS patients diagnosed with Kaposi's sarcoma (KS), we calculated survival for 1,015 patients reported in San Francisco between July 1981 and December 31, 1987, representing 22% of total patients reported. These patients had a definitive initial diagnosis of KS, and developed no other diseases within 3 months of diagnosis. Patients were followed prospectively through December 31, 1988. All patients evaluated in this study were men. Survival was evaluated for subgroups based on age, race and ethnicity, year of diagnosis, and transmission category. The median survival for patients diagnosed with KS alone was 17.0 months, with a 5-year survival rate of 8.7%. Poorer prognosis was found for patients with older age at diagnosis and with later year of diagnosis. Proportional hazards analysis indicated that age (p less than 0.001) and year of diagnosis (p less than 0.05) were significant independent predictors of survival, while race or ethnicity and risk group were not.

The epidemiology of AIDS-related Kaposi's sarcoma in San Francisco.

To clarify further the epidemiology of AIDS-related Kaposi's sarcoma (KS) in San Francisco, we reviewed AIDS cases reported to the San Francisco Department of Public Health through August 31, 1990. Of the 7,119 patients reported, 2,346 (33%) had been diagnosed as having KS: 1,716 (73%) as their presenting clinical manifestation of AIDS and 648 (27%) as a later manifestation. Of these 2,364 KS patients, 2,075 (88%) were homosexual or bisexual men without histories of intravenous drug use, and 273 (12%) were homosexual or bisexual intravenous drug users. From 1981 to August 1989, the proportion of AIDS patients presenting with KS declined from 55 to 19% (p less than 0.001). However, the number of patients being diagnosed with KS has increased along with the overall number of AIDS patients, but this increase was less than the increase in number of patients with other opportunistic infections and malignancies. KS patients were less likely than patients without KS to be reported through an active surveillance system and less likely to be found through retrospective reviews of medical records, death certificates, and obituaries. We conclude that the proportion of AIDS patients with KS is continuing to decline in San Francisco and that this decline is not an artifact of the AIDS surveillance system.