Streamflow Prediction in Highly Regulated, Transboundary Watersheds Using Multi-Basin Modeling and Remote Sensing Imagery.

Despite the potential of remote sensing for monitoring reservoir operation, few studies have investigated the extent to which reservoir releases can be inferred across different spatial and temporal scales. Through evaluating 21 reservoirs in the highly regulated Greater Mekong region, remote sensing imagery was found to be useful in estimating daily storage volumes for within-year and over-year reservoirs (correlation coefficients [CC] ≥ 0.9, normalized root mean squared error [NRMSE] ≤ 31%), but not for run-of-river reservoirs (CC < 0.4, 40% ≤ NRMSE ≤ 270%). Given a large gap in the number of reservoirs between global and local databases, the proposed framework can improve representation of existing reservoirs in the global reservoir database and thus human impacts in hydrological models. Adopting an Integrated Reservoir Operation Scheme within a multi-basin model was found to overcome the limitations of remote sensing and improve streamflow prediction at ungauged cascade reservoir systems where previous modeling approaches were unsuccessful. As a result, daily regulated streamflow was predicted competently across all types of reservoirs (median values of CC = 0.65, NRMSE = 8%, and Kling-Gupta efficiency [KGE] = 0.55) and downstream hydrological stations (median values of CC = 0.94, NRMSE = 8%, and KGE = 0.81). The findings are valuable for helping to understand the impacts of reservoirs and dams on streamflow and for developing more useful adaptation measures to extreme events in data sparse river basins.

A scalable, integrated intervention to engage people who inject drugs in HIV care and medication-assisted treatment (HPTN 074): a randomised, controlled phase 3 feasibility and efficacy study.

BACKGROUND: People who inject drugs (PWID) have a high incidence of HIV, little access to antiretroviral therapy (ART) and medication-assisted treatment (MAT), and high mortality. We aimed to assess the feasibility of a future controlled trial based on the incidence of HIV, enrolment, retention, and uptake of the intervention, and the efficacy of an integrated and flexible intervention on ART use, viral suppression, and MAT use. METHODS: This randomised, controlled vanguard study was run in Kyiv, Ukraine (one community site), Thai Nguyen, Vietnam (two district health centre sites), and Jakarta, Indonesia (one hospital site). PWID who were HIV infected (index participants) and non-infected injection partners were recruited as PWID network units and were eligible for screening if they were aged 18-45 years (updated to 18-60 years 8 months into study), and active injection drug users. Further eligibility criteria for index participants included a viral load of 1000 copies per mL or higher, willingness and ability to recruit at least one injection partner who would be willing to participate. Index participants were randomly assigned via a computer generated sequence accessed through a secure web portal (3:1) to standard of care or intervention, stratified by site. Masking of assignment was not possible due to the nature of intervention. The intervention comprised systems navigation, psychosocial counselling, and ART at any CD4 count. Local ART and MAT services were used. Participants were followed up for 12-24 months. The primary objective was to assess the feasibility of a future randomised controlled trial. To achieve this aim we looked at the following endpoints: HIV incidence among injection partners in the standard of care group, and enrolment and retention of HIV-infected PWID and their injection partners and the uptake of the integrated intervention. The study was also designed to assess the feasibility, barriers, and uptake of the integrated intervention. Endpoints were assessed in a modified intention-to-treat popualtion after exclusion of ineligible participants. This trial is registered on ClinicalTrials.gov, NCT02935296, and is active but not recruiting new participants. FINDINGS: Between Feb 5, 2015, and June 3, 2016, 3343 potential index participants were screened, of whom 502 (15%) were eligible and enrolled. 1171 injection partners were referred, and 806 (69%) were eligible and enrolled. Index participants were randomly assigned to intervention (126 [25%]) and standard of care (376 [75%]) groups. At week 52, most living index participants (389 [86%] of 451) and partners (567 [80%] of 710) were retained, and self-reported ART use was higher among index participants in the intervention group than those in the standard of care group (probability ratio [PR] 1·7, 95% CI 1·4-1·9). Viral suppression was also higher in the intervention group than in the standard of care group (PR 1·7, 95% CI 1·3-2·2). Index participants in the intervention group reported more MAT use at 52 weeks than those in the standard of care group (PR 1·7, 95% CI 1·3-2·2). Seven incident HIV infections occurred, and all in injection partners in the standard of care group (intervention incidence 0·0 per 100 person-years, 95% CI 0·0-1·7; standard of care incidence 1·0 per 100 person-years, 95% CI 0·4-2·1; incidence rate difference -1·0 per 100 person-years, 95% CI -2·1 to 1·1). No severe adverse events due to the intervention were recorded. INTERPRETATION: This vanguard study provides evidence that a flexible, scalable intervention increases ART and MAT use and reduces mortality among PWID. The low incidence of HIV in both groups impedes a future randomised, controlled trial, but given the strength of the effect of the intervention, its implementation among HIV-infected PWID should be considered. FUNDING: US National Institutes of Health.

A prospective "test-and-treat" demonstration project among people who inject drugs in Vietnam.

INTRODUCTION: Modelling suggests that early diagnosis and immediate antiretroviral therapy (ART) among key populations would have a substantial impact in reducing HIV transmission and mortality in Vietnam. An implementation research project of "test-and-treat" among people who inject drugs (PWID) was developed to inform effective roll-out of such interventions. METHODS: "Test-and-treat" was offered to PWID in two high burden provinces, Thai Nguyen and Thanh Hoa. The interventions comprised the offer of biannual HIV testing and immediate ART, irrespective of CD4 count. PWID were enrolled between April 2014 and July 2015 and followed up for 12 months, and retention, HIV viral load (VL) and risk behaviours were assessed. Retention in care of this prospective cohort was compared with the retention among men enrolled in care in the preceding period (April 2012 to March 2013) at the same clinics when ART was initiated at CD4 cell count ≤350 cells/mm3 . RESULTS: In total, 287 HIV positive PWID started immediate ART. The majority (98%) were men; median age was 34; and median (interquartile range) CD4 count was 199 (50 to 402) cells/mm3 . After 12 months, 238 participants (83%) were retained on ART, and 205 achieved viral suppression (<1000 copies/mL) (92% among those in whom VL was measured, 71% overall). Baseline CD4 count ≤100 cells/mm3 and history of imprisonment were associated with lower retention and viral suppression, while engagement in methadone maintenance was associated with higher retention. Retention in care was higher in the "test-and-treat" cohort (83%) compared with men enrolled in care in the preceding period (78%), primarily because lost-to-follow-up during pre-ART care was eliminated. No decline in consistent condom use and clean needle use was observed. CONCLUSIONS: Early ART initiation resulted in successful treatment outcomes among PWID, with no observed increase in self-reported risk behaviours, suggesting feasibility and potential effectiveness of "test-and-treat" approach. The results also call for differentiated care for PWID, including promoting early diagnosis and engagement in methadone maintenance therapy while enhancing care for those with advanced HIV disease and history of imprisonment.

The potential impact of expanding antiretroviral therapy and combination prevention in Vietnam: towards elimination of HIV transmission.

BACKGROUND: Few studies have assessed the effects of antiretroviral therapy (ART) to prevent HIV transmission in Asian HIV epidemics. Vietnam has a concentrated HIV epidemic with the highest prevalence among people who inject drugs. We investigated the impact of expanded HIV testing and counseling (HTC) and early ART, combined with other prevention interventions on HIV transmission. METHODS: A deterministic mathematical model was developed using HIV prevalence trends in Can Tho province, Vietnam. Scenarios included offering periodic HTC and immediate ART with and without targeting subpopulations and examining combined strategies with methadone maintenance therapy and condom use. RESULTS: From 2011 to 2050, maintaining current interventions will incur an estimated 18,115 new HIV infections and will cost US $22.1 million (reference scenario). Annual HTC and immediate treatment, if offered to all adults, will reduce new HIV infections by 14,513 (80%) and will cost US $76.9 million. Annual HTC and immediate treatment offered only to people who inject drugs will reduce new infections by 13,578 (75%) and will cost only US $23.6 million. Annual HTC and immediate treatment for key populations, combined with scale-up of methadone maintenance therapy and condom use, will reduce new infections by 14,723 (81%) with similar costs (US $22.7 million). This combination prevention scenario will reduce the incidence to less than 1 per 100,000 in 14 years and will result in a relative cost saving after 19 years. CONCLUSIONS: Targeted periodic HTC and immediate ART combined with other interventions is cost-effective and could lead to potential elimination of HIV in Can Tho.