Geographic Information Systems (GIS) and spatial analysis are emerging tools for global health, but it is unclear to what extent they have been applied to HIV research in Africa. To help inform ...researchers and program implementers, this scoping review documents the range and depth of published HIV-related GIS and spatial analysis research studies conducted in Africa.
A systematic literature search for articles related to GIS and spatial analysis was conducted through PubMed, EMBASE, and Web of Science databases. Using pre-specified inclusion criteria, articles were screened and key data were abstracted. Grounded, inductive analysis was conducted to organize studies into meaningful thematic areas.
The search returned 773 unique articles, of which 65 were included in the final review. 15 different countries were represented. Over half of the included studies were published after 2014. Articles were categorized into the following non-mutually exclusive themes: (a) HIV geography, (b) HIV risk factors, and (c) HIV service implementation. Studies demonstrated a broad range of GIS and spatial analysis applications including characterizing geographic distribution of HIV, evaluating risk factors for HIV, and assessing and improving access to HIV care services.
GIS and spatial analysis have been widely applied to HIV-related research in Africa. The current literature reveals a diversity of themes and methodologies and a relatively young, but rapidly growing, evidence base.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Tuberculosis (TB) incidence in South Africa is among the highest globally. Initial loss to follow-up (ILFU), defined as not starting on TB treatment within 28 days of testing positive, is undermining ...control efforts. We assessed the feasibility, acceptability, and potential of a mHealth application to reduce ILFU.
An mHealth application was developed to capture patients TB investigation data, provide results and monitor treatment initiation. This was implemented in two primary health clinics (PHC) in inner-city Johannesburg. Feasibility was assessed by comparing documentation of personal details, specimen results for same individuals during implementation period (paper register and Mhealth application). Effectiveness was assessed by comparing proportion of patients with results within 48 hours, and proportion started on treatment within 28 days of testing TB positive during pre- implementation (paper register) and implementation (mHealth application) periods. In-depth interviews with patients and providers were conducted to assess acceptability of application.
Pre-implementation, 457 patients were recorded in paper registers 195 (42.7%) male, median age 34 years (interquartile range IQR (28-40), 45 (10.5%) sputum Xpert positive. During implementation, 319 patients were recorded in paper register and the mHealth application 131 (41.1%) male, median age 32 years (IQR 27-38), 33 (10.3%) sputum Xpert positive. The proportion with complete personal details: mHealth 95.0% versus paper register 94.0%, (p = 0.54) and proportion with documented results: mHealth 97.4% versus paper register 97.8%, (p = 0.79) were not different in the two methods. The proportion of results available within 48 hours: mHealth 96.8% versus paper register 68.6%), (p <0.001), and the proportion on treatment within 28 days mHealth 28/33 (84.8%) versus paper register 30/44 (68.2%), (p = 0.08) increased during implementation but was not statistically significant. In-depth interviews showed that providers easily integrated the mHealth application into routine TB investigation and patients positively received the delivery of results via text message. Time from sputum collection to TB treatment initiation decreased from 4 days (pre-implementation) to 3 days but was not statistically significant.
We demonstrated that implementation of the mHealth application was feasible, acceptable to health care providers and patients, and has potential to reduce the time to TB treatment initiation and ILFU in PHC settings.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
HIV prevalence varies markedly throughout Africa, and it is often presumed areas of higher HIV prevalence (i.e., hotspots) serve as sources of infection to neighboring areas of lower prevalence. ...However, the small-scale geography of migration networks and movement of HIV-positive individuals between communities is poorly understood. Here, we use population-based data from ~22,000 persons of known HIV status to characterize migratory patterns and their relationship to HIV among 38 communities in Rakai, Uganda with HIV prevalence ranging from 9 to 43%. We find that migrants moving into hotspots had significantly higher HIV prevalence than migrants moving elsewhere, but out-migration from hotspots was geographically dispersed, contributing minimally to HIV burden in destination locations. Our results challenge the assumption that high prevalence hotspots are drivers of transmission in regional epidemics, instead suggesting that migrants with high HIV prevalence, particularly women, selectively migrate to these areas.
Human resource limitations are a challenge to the delivery of antiretroviral therapy (ART) in low-resource settings. We conducted a cluster randomized trial to assess the effect of community-based ...peer health workers (PHW) on AIDS care of adults in Rakai, Uganda.
15 AIDS clinics were randomized 2:1 to receive the PHW intervention (n = 10) or control (n = 5). PHW tasks included clinic and home-based provision of counseling, clinical, adherence to ART, and social support. Primary outcomes were adherence and cumulative risk of virologic failure (>400 copies/mL). Secondary outcomes were virologic failure at each 24 week time point up to 192 weeks of ART. Analysis was by intention to treat. From May 2006 to July 2008, 1336 patients were followed. 444 (33%) of these patients were already on ART at the start of the study. No significant differences were found in lack of adherence (<95% pill count adherence risk ratio RR 0.55, 95% confidence interval CI 0.23-1.35; <100% adherence RR 1.10, 95% CI 0.94-1.30), cumulative risk of virologic failure (RR 0.81, 95% CI 0.61-1.08) or in shorter-term virologic outcomes (24 week virologic failure RR 0.93, 95% CI 0.65-1.32; 48 week, RR 0.83, 95% CI 0.47-1.48; 72 week, RR 0.81, 95% CI 0.44-1.49). However, virologic failure rates >or=96 weeks into ART were significantly decreased in the intervention arm compared to the control arm (96 week failure RR 0.50, 95% CI 0.31-0.81; 120 week, RR 0.59, 95% CI 0.22-1.60; 144 week, RR 0.39, 95% CI 0.16-0.95; 168 week, RR 0.30, 95% CI 0.097-0.92; 192 week, RR 0.067, 95% CI 0.0065-0.71).
A PHW intervention was associated with decreased virologic failure rates occurring 96 weeks and longer into ART, but did not affect cumulative risk of virologic failure, adherence measures, or shorter-term virologic outcomes. PHWs may be an effective intervention to sustain long-term ART in low-resource settings.
ClinicalTrials.gov NCT00675389.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Summary The promise of combination HIV prevention—the application of multiple HIV prevention interventions to maximise population-level effects—has never been greater. However, to succeed in ...achieving significant reductions in HIV incidence, an additional concept needs to be considered: combination implementation. Combination implementation for HIV prevention is the pragmatic, localised application of evidence-based strategies to enable high sustained uptake and quality of interventions for prevention of HIV. In this Review, we explore diverse implementation strategies including HIV testing and counselling models, task shifting, linkage to and retention in care, antiretroviral therapy support, behaviour change, demand creation, and structural interventions, and discusses how they could be used to complement HIV prevention efforts such as medical male circumcision and treatment as prevention. HIV prevention and treatment have arrived at a pivotal moment when combination efforts might result in substantial enough population-level effects to reverse the epidemic and drive towards elimination of HIV. Only through careful consideration of how to implement and operationalise HIV prevention interventions will the HIV community be able to move from clinical trial evidence to population-level effects.
Antenatal alcohol use is linked to adverse maternal and neonatal outcomes. Uganda has one of the highest rates of alcohol use in sub-Saharan Africa, but the prevalence of antenatal alcohol use has ...not been reported in the Rakai region.
We used cross-sectional data from pregnant women in the Rakai Community Cohort Study between March 2017 and September 2018. Using bivariate and multivariable analyses, we assessed associations between self-reported antenatal alcohol use and sociodemographic characteristics, intimate partner violence (IPV), and HIV status.
Among 960 pregnant women, the median age was 26 years, 35% experienced IPV in the past 12 months, 13% were living with HIV, and 33% reported alcohol use during their current pregnancy. After adjusting for marital status, education, smoking, and HIV status; Catholic religion (AOR: 3.54; 95% CI: 1.89-6.64; compared to other), bar/restaurant work (AOR: 2.40; 95% CI: 1.17-4.92; compared to agriculture), >one sex partner in past year (AOR: 1.92; 95% CI: 1.17-3.16), a partner that drank before sex in past year (AOR: 2.01; 95% CI: 1.48-2.74), and past year IPV (AOR: 1.55; 95% CI: 1.14-2.11) were associated with antenatal alcohol use.
We found that alcohol use during pregnancy was common and associated with religion, occupation, higher numbers of past year sex partners, having a partner who drank before sex in the past 12 months, and IPV experience. More research is needed to understand the quantity, frequency, and timing of antenatal alcohol use; and potential impacts on neonates; and to identify services that are acceptable and effective among pregnant women.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
After HIV diagnosis, timely entry into HIV medical care and retention in that care are essential to the provision of effective antiretroviral therapy (ART). Adherence to ART is among the key ...determinants of successful HIV treatment outcome and is essential to minimize the emergence of drug resistance. The International Association of Physicians in AIDS Care convened a panel to develop evidence-based recommendations to optimize entry into and retention in care and ART adherence for people with HIV.
A systematic literature search was conducted to produce an evidence base restricted to randomized, controlled trials and observational studies with comparators that had at least 1 measured biological or behavioral end point. A total of 325 studies met the criteria. Two reviewers independently extracted and coded data from each study using a standardized data extraction form. Panel members drafted recommendations based on the body of evidence for each method or intervention and then graded the overall quality of the body of evidence and the strength for each recommendation.
Recommendations are provided for monitoring entry into and retention in care, interventions to improve entry and retention, and monitoring of and interventions to improve ART adherence. Recommendations cover ART strategies, adherence tools, education and counseling, and health system and service delivery interventions. In addition, they cover specific issues pertaining to pregnant women, incarcerated individuals, homeless and marginally housed individuals, and children and adolescents, as well as substance use and mental health disorders. Recommendations for future research in all areas are also provided.
The need for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) next-generation vaccines has been highlighted by the rise of variants of concern (VoCs) and the long-term threat of emerging ...coronaviruses. Here, we design and characterize four categories of engineered nanoparticle immunogens that recapitulate the structural and antigenic properties of the prefusion SARS-CoV-2 spike (S), S1, and receptor-binding domain (RBD). These immunogens induce robust S binding, ACE2 inhibition, and authentic and pseudovirus neutralizing antibodies against SARS-CoV-2. A spike-ferritin nanoparticle (SpFN) vaccine elicits neutralizing titers (ID50 > 10,000) following a single immunization, whereas RBD-ferritin nanoparticle (RFN) immunogens elicit similar responses after two immunizations and also show durable and potent neutralization against circulating VoCs. Passive transfer of immunoglobulin G (IgG) purified from SpFN- or RFN-immunized mice protects K18-hACE2 transgenic mice from a lethal SARS-CoV-2 challenge. Furthermore, S-domain nanoparticle immunization elicits ACE2-blocking activity and ID50 neutralizing antibody titers >2,000 against SARS-CoV-1, highlighting the broad response elicited by these immunogens.
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•Iterative structure-based design of SARS-CoV-2 ferritin nanoparticle immunogens•Elicitation of potent neutralizing activity against SARS-CoV-2, VoCs, and SARS-CoV-1•Passively transferred immune-IgG protects K18-hACE2 mice from SARS-CoV-2 challenge
Joyce et al. generate four categories of engineered SARS-CoV-2 ferritin nanoparticle immunogens using structure-based vaccine design that recapitulate the prefusion SARS-CoV-2 spike, S1, and RBD. These immunogens induce robust and protective neutralizing antibody responses against SARS-CoV-2 and elicit potent neutralization against variants of concern and the heterologous SARS-CoV-1.
Timing of HIV-1 reservoir formation is important for informing HIV cure efforts. It is unclear how much of the variability seen in dating reservoir formation is due to sampling and gene-specific ...differences. We used a Bayesian extension of root to tip regression (bayroot) to re-estimate formation date distributions in participants from Swedish and South African cohorts, and assessed the impact of variable timing, frequency, and depth of sampling on these estimates. Significant shifts in formation date distributions were only observed with use of faster-evolving genes, while timing, frequency, and depth of sampling had minor or no significant effect on estimates.
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