Mobility and Clinic Switching Among Postpartum Women Considered Lost to HIV Care in South Africa.

This version is the Accepted Manuscript, and was published in final edited form as: J Acquir Immune Defic Syndr. 2017 April 01; 74(4): 383–389. doi:10.1097/QAI.0000000000001284OBJECTIVE: Retention in HIV care, particularly among postpartum women, is a challenge to national antiretroviral therapy programs. Retention estimates may be underestimated because of unreported transfers. We explored mobility and clinic switching among patients considered lost to follow-up (LTFU). DESIGN: Observational cohort study. METHODS: Of 788 women initiating antiretroviral therapy during pregnancy at 6 public clinics in Johannesburg, South Africa, 300 (38.1%) were LTFU (no visit ≥3 months). We manually searched for these women in the South African National Health Laboratory Services database to assess continuity of HIV care. We used geographic information system tools to map mobility to new facilities. RESULTS: Over one-third (37.6%) of women showed evidence of continued HIV care after LTFU. Of these, 67.0% continued care in the same province as the origin clinic. Compared with those who traveled outside of the province for care, these same-province "clinic shoppers" stayed out-of-care longer {median 373 days [interquartile range (IQR): 175-790] vs. 175.5 days (IQR: 74-371)} and had a lower CD4 cell count on re-entry [median 327 cells/μL (IQR: 196-576) vs. 493 cells/μL (IQR: 213-557). When considering all women with additional evidence of care as engaged in care, cohort LTFU dropped from 38.1% to 25.0%. CONCLUSION: We found evidence of continued care after LTFU and identified local and national clinic mobility among postpartum women. Laboratory records do not show all clinic visits and manual matching may have been under- or overestimated. A national health database linked to a unique identifier is necessary to improve reporting and patient care among highly mobile populations

Toxicity of leachate from weathering plastics: An exploratory screening study with Nitocra spinipes

AbstractBetween 60% and 80% of all marine litter is plastic. Leachate from plastics has previously been shown to cause acute toxicity in the freshwater species Daphnia magna. Here, we present an initial screening of the marine environmental hazard properties of leachates from weathering plastics to the marine harpacticoid copepod [Crustacea] Nitocra spinipes. Twenty-one plastic products made of different polymeric materials were leached and irradiated with artificial sunlight. Eight of the twenty-one plastics (38%) produced leachates that caused acute toxicity. Differences in toxicity were seen for different plastic products, and depending on the duration of irradiation. There was no consistent trend in how toxicity of leachate from plastics changed as a function of irradiation time. Leachate from four plastics became significantly more toxic after irradiation, two became significantly less toxic and two did not change significantly. Analysis of leachates from polyvinyl chloride (PVC) by liquid chromatography coupled to a full-scan high-resolution mass spectrometer showed that the leachates were a mixture of substances, but did not show evidence of degradation of the polymer backbone. This screening study demonstrates that leachates from different plastics differ in toxicity to N. spinipes and that the toxicity varies under simulated weathering

Assessment of rates of recanting and hair testing as a biological measure of drug use in a general population sample of young people

AIMS: We investigate the extent of and factors associated with denial of previously reported cannabis and other illicit drug use, and assess the potential of hair testing for measuring substance use in general population samples. DESIGN: Birth cohort study. SETTING: United Kingdom, 1991–present. PARTICIPANTS: A total of 3643 participants who provided hair and self‐report measures of cannabis and other illicit drug use in the Avon Longitudinal Study of Parents and Children (ALSPAC) at age 18 years. MEASUREMENTS: Denial of ever use of cannabis and other illicit drugs at age 18 following previously reported use. Positive hair drug tests for cannabis and other illicit drugs, and expected numbers of false positives and false negatives based on expected sensitivity and specificity. FINDINGS: Cannabis and other illicit drug use was reported by 1223 and 393 individuals, respectively, before age 18 years. Of these 176 (14.4%) and 99 (25.2%), respectively, denied use at age 18. Denial of cannabis use decreased with the reporting of other substances and antisocial behaviour. Cannabis and other illicit drug use at age 18 was reported by 547 (22.5%) and 203 (8.4%) individuals, respectively. Of these, 111 (20.3%) and 13 (6.4%) were hair‐positive for cannabis and other illicit drugs, respectively. Based on hair testing for cannabis use we expect 0 [95% confidence interval (CI) = 0–169] false positives and 394 (95% CI = 323–449) false negatives compared to observed 362 potential false positives and 436 potential false negatives based on self‐report. In hair‐positive individuals, reporting the use of other substances and antisocial behaviour decreased the odds of a negative self‐report. CONCLUSIONS: Hair analysis provides an unreliable marker of substance use in general population samples. People who report more frequent substance use before age 18 are less likely to later deny previous substance use at age 18 than people who report occasional use

Solving the puzzle of discrepant quasar variability on monthly time-scales implied by SDSS and CRTS data sets

We present an improved photometric error analysis for the 7 100 CRTS (Catalina Real-Time Transient Survey) optical light curves for quasars from the SDSS (Sloan Digital Sky Survey) Stripe 82 catalogue. The SDSS imaging survey has provided a time-resolved photometric data set, which greatly improved our understanding of the quasar optical continuum variability: Data for monthly and longer time-scales are consistent with a damped random walk (DRW). Recently, newer data obtained by CRTS provided puzzling evidence for enhanced variability, compared to SDSS results, on monthly time-scales. Quantitatively, SDSS results predict about 0.06 mag root-mean-square (rms) variability for monthly time-scales, while CRTS data show about a factor of 2 larger rms, for spectroscopically confirmed SDSS quasars. Our analysis has successfully resolved this discrepancy as due to slightly underestimated photometric uncertainties from the CRTS image processing pipelines. As a result, the correction for observational noise is too small and the implied quasar variability is too large. The CRTS photometric error correction factors, derived from detailed analysis of non-variable SDSS standard stars that were re-observed by CRTS, are about 20–30 per cent, and result in reconciling quasar variability behaviour implied by the CRTS data with earlier SDSS results. An additional analysis based on independent light curve data for the same objects obtained by the Palomar Transient Factory provides further support for this conclusion. In summary, the quasar variability constraints on weekly and monthly time-scales from SDSS, CRTS and PTF surveys are mutually compatible, as well as consistent with DRW model

Socioeconomic factors and other sources of variation in the prevalence of genital chlamydia infections: A systematic review and meta-analysis

BACKGROUND: The success of chlamydia screening programmes relies on their ability to effectively target those with greatest need. Young people from disadvantaged backgrounds may be at greater need for chlamydia screening, but existing evidence on the variation of prevalence with social position is inconclusive. We carried out a systematic review to examine variation in chlamydia prevalence in populations and possible sources of this variation. METHODS: Studies were eligible if they reported chlamydia prevalence derived from population-based samples that included young people aged 15–24 years from Europe, North America or Australia. Systematic searches of the following databases were undertaken from their inception to November 2014: MEDLINE, Embase, Web of Science and PsychINFO. There were no restrictions by language or publication date. Independent screening for eligibility and data extraction were carried out by two reviewers. Where possible, data were pooled in a meta-analysis using a random effects model. Heterogeneity was further investigated using meta-regression techniques. RESULTS: Of 1248 unique titles and abstracts and 263 potentially relevant full texts, 29 studies were eligible for inclusion. There was relatively strong evidence that disadvantaged young people had an increased risk of having a chlamydia infection across multiple measures of disadvantage, including lower educational attainment (OR 1.94, 95 % CI: 1.52 to 2.47), lower occupational class (OR 1.49, 95 % CI: 1.07 to 2.08) and residence in deprived areas (OR 1.76, 95 % CI: 1.15 to 2.71) with an overall OR of 1.66 (95 % CI: 1.37 to 2.02). Socioeconomic disadvantage was associated with chlamydia infection in both men and women. There was weaker evidence that prevalence estimates also varied by gender and age. CONCLUSIONS: This review provides evidence of a consistent association between socioeconomic disadvantage and higher risk of Chlamydia infection. This association may reflect a number of factors including social variation in engagement with Chlamydia control programmes. Chlamydia screening could therefore reduce or increase health inequalities, depending on service provision and uptake by different socioeconomic groups. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12889-015-2069-7) contains supplementary material, which is available to authorized users

Prevalence of HIV in workforces in southern Africa, 2000 - 2001

Objectives. Most data on HIV prevalence in low-risk populations in sub-Saharan Africa are drawn from sentinel surveys of pregnant women attending antenatal clinics and are not representative of formal sector workforces. We surveyed workforces in southern Africa to determine HIV prevalence among formally employed, largely male populations. Methods. Voluntary, anonymous, unlinked seroprevalence surveys of 34 workforces with 44 000 employees were carried out in South Africa, Botswana, and Zambia in 2000 - 2001. Results were stratified to obtain estimates of prevalence by industrial sector, location, age, sex, and job level. Results. Average HIV prevalence for the entire sample was 16.6% (95% CI: 16.3 - 17.0%). Country-wide prevalence was 14.5% (14.1 - 14.9%) in South Africa, 17.9% (17.1 - 18.7%) in Zambia, and 24.6% (23.6 - -25.7%) in Botswana. Among industrial sectors, mining (18.0%, 17.6 - 18.5%) and metal processing (17.3%, 15.9 - 18.7%) had the highest infection rates. Males, who comprised 85% of participants of known sex, were more likely (16.3%, 15.3 - 17.4%) to be infected than were females (10.7%, 8.7 - 12.7%). Contract (23%, 21.9 - 24.1%), unskilled (18.3%, 17.5 - 19.1%), and semi-skilled workers (18.7%, 18.1 - 19.4%) were much more likely to be infected than were skilled workers (10.5%, 9.5 - 11.4%) and managers (4.5%, 3.4 - 5.6%). Participation in the surveys averaged 63% of eligible employees. Conclusions. HIV prevalence among formally employed workers in southern Africa shows different patterns than among antenatal clinic attendees. Anonymous workplace surveys generate prevalence estimates for demographic groups that are not represented in antenatal surveys and can strengthen support for prevention and treatment interventions. S Afr Med J 2004; 94: 125-130