Integrated management of HIV, diabetes, and hypertension in sub-Saharan Africa (INTE-AFRICA): a pragmatic cluster-randomised, controlled trial.

BACKGROUND: In sub-Saharan Africa, health-care provision for chronic conditions is fragmented. The aim of this study was to determine whether integrated management of HIV, diabetes, and hypertension led to improved rates of retention in care for people with diabetes or hypertension without adversely affecting rates of HIV viral suppression among people with HIV when compared to standard vertical care in medium and large health facilities in Uganda and Tanzania. METHODS: In INTE-AFRICA, a pragmatic cluster-randomised, controlled trial, we randomly allocated primary health-care facilities in Uganda and Tanzania to provide either integrated care or standard care for HIV, diabetes, and hypertension. Random allocation (1:1) was stratified by location, infrastructure level, and by country, with a permuted block randomisation method. In the integrated care group, participants with HIV, diabetes, or hypertension were managed by the same health-care workers, used the same pharmacy, had similarly designed medical records, shared the same registration and waiting areas, and had an integrated laboratory service. In the standard care group, these services were delivered vertically for each condition. Patients were eligible to join the trial if they were living with confirmed HIV, diabetes, or hypertension, were aged 18 years or older, were living within the catchment population area of the health facility, and were likely to remain in the catchment population for 6 months. The coprimary outcomes, retention in care (attending a clinic within the last 6 months of study follow-up) for participants with either diabetes or hypertension (tested for superiority) and plasma viral load suppression for those with HIV (>1000 copies per mL; tested for non-inferiority, 10% margin), were analysed using generalised estimating equations in the intention-to-treat population. This trial is registered with ISCRTN 43896688. FINDINGS: Between June 30, 2020, and April 1, 2021 we randomly allocated 32 health facilities (17 in Uganda and 15 in Tanzania) with 7028 eligible participants to the integrated care or the standard care groups. Among participants with diabetes, hypertension, or both, 2298 (75·8%) of 3032 were female and 734 (24·2%) of 3032 were male. Of participants with HIV alone, 2365 (70·3%) of 3365 were female and 1000 (29·7%) of 3365 were male. Follow-up lasted for 12 months. Among participants with diabetes, hypertension, or both, the proportion alive and retained in care at study end was 1254 (89·0%) of 1409 in integrated care and 1457 (89·8%) of 1623 in standard care. The risk differences were -0·65% (95% CI -5·76 to 4·46; p=0·80) unadjusted and -0·60% (-5·46 to 4·26; p=0·81) adjusted. Among participants with HIV, the proportion who had a plasma viral load of less than 1000 copies per mL was 1412 (97·0%) of 1456 in integrated care and 1451 (97·3%) of 1491 in standard care. The differences were -0·37% (one-sided 95% CI -1·99 to 1·26; pnon-inferiority<0·0001 unadjusted) and -0·36% (-1·99 to 1·28; pnon-inferiority<0·0001 adjusted). INTERPRETATION: In sub-Saharan Africa, integrated chronic care services could achieve a high standard of care for people with diabetes or hypertension without adversely affecting outcomes for people with HIV. FUNDING: European Union Horizon 2020 and Global Alliance for Chronic Diseases.

Temperature-tunable UV generation using an Alexandrite laser and PPLN waveguides.

We present a simple and novel technique for achieving ultra-violet (UV) wavelength-tunable laser operation in the continuous-wave regime. Wavelength tunable operation in the near infrared is obtained from a compact two-mirror Alexandrite laser cavity by temperature tuning of the laser crystal. Second-harmonic-generation to the UV is then achieved at 376-379 nm and 384-386 nm by temperature tuning of a periodically-poled lithium-niobate (PPLN) waveguide. A maximum UV power of 1.3 mW from 185 mW infra-red pump throughput is obtained from a third-order PPLN Λ=6.1µm grating. These results show promising potential for simple and wavelength tunable access to wavelengths at 360-400 nm.

Short single-frequency self-pulsing Brillouin-Raman distributed feedback fiber laser.

We demonstrate that the stimulated Brillouin scattering of a 250 mm long distributed feedback Raman fiber laser can self-pulse with repetition rates up to 7 MHz, pulse widths of 25 ns, and peak powers of 1.2 W. While both CW and pulsed lasing are produced from a bespoke grating at 1119 nm this laser design could be constructed at almost any wavelength, as the Raman and Brillouin gain regions are relative to the pump wavelength. The laser has a low lasing threshold for a Raman laser of 0.55 W, a peak slope efficiency of 14 %, and a maximum average output of 0.25 W. An investigation of beating between pure Raman and Raman-pumped Brillouin lasing shows that the outputs of the two processes are highly correlated and thus the Brillouin lasing is essentially single-frequency when CW and near transform limited for pulsed operation. A phenomenological model of the Raman-Brillouin interaction shows that the pulsing behaviour of such a cavity is expected and produces very similar pulsing to that the seen in experimental results.

Reprogramming RNA processing: an emerging therapeutic landscape.

The production of a mature mRNA requires coordination of multiple processing steps, which ultimately control its content, localization, and stability. These steps include some of the largest macromolecular machines in the cell, which were, until recently, considered undruggable due to their biological complexity. Building from an expanded understanding of the underlying mechanisms that drive these processes, a new wave of therapeutics is seeking to target RNA processing. With a focus on impacting gene regulation at the RNA level, such modalities offer potential for sequence-specific resolution in drug design. Here, we review our current understanding of RNA-processing events and their role in gene regulation, with a focus on the therapeutic opportunities that have emerged within this landscape.

Ethics review of COVID-19 human challenge studies: A joint HRA/WHO workshop.

This report of a joint World Health Organization (WHO) and United Kingdom (UK) Health Research Authority (HRA) workshop discusses the ethics review of the first COVID-19 human challenge studies, undertaken in the midst of the pandemic. It reviews the early efforts of international and national institutions to define the ethical standards required for COVID-19 human challenge studies and create the frameworks to ensure rigorous and timely review of these studies. This report evaluates the utility of the WHO's international guidance document Key criteria for the ethical acceptability of COVID-19 human challenge studies (WHO Key Criteria) as a practical resource for the ethics review of COVID-19 human challenge studies. It also assesses the UK HRA's approach to these complex ethics reviews, including the formation of a Specialist Ad-Hoc Research Ethics Committee (REC) for COVID-19 Human Challenge Studies to review all current and future COVID-19 human challenge studies. In addition, the report outlines the reflections of REC members and researchers regarding the ethics review process of the first COVID-19 human challenge studies. Finally, it considers the potential ongoing scientific justification for COVID-19 human challenge studies, particularly in relation to next-generation vaccines and optimisation of vaccination schedules. Overall, there was broad agreement that the WHO Key Criteria represented an international consensus document that played a powerful role in setting norms and delineating the necessary conditions for the ethical acceptability of COVID-19 human challenge studies. Workshop members suggested that the WHO Key Criteria could be practically implemented to support researchers and ethics reviewers, including in the training of ethics committee members. In future, a wider audience may be engaged by the original document and potential additional materials, informed by the experiences of those involved in the first COVID-19 human challenge studies outlined in this document.

WHO preferred product characteristics for monoclonal antibodies for passive immunization against respiratory syncytial virus (RSV) disease in infants - Key considerations for global use.

World Health Organization (WHO) preferred product characteristics describe preferences for product attributes that would help optimize value and use to address global public health needs, with a particular focus on low- and middle-income countries. Having previously published preferred product characteristics for both maternal and paediatric respiratory syncytial virus (RSV) vaccines, WHO recently published preferred product characteristics for monoclonal antibodies to prevent severe RSV disease in infants. This article summarizes the key attributes from the preferred product characteristics and discusses key considerations for future access and use of preventive RSV monoclonal antibodies.

Duration of effectiveness of vaccines against SARS-CoV-2 infection and COVID-19 disease: results of a systematic review and meta-regression.

BACKGROUND: Knowing whether COVID-19 vaccine effectiveness wanes is crucial for informing vaccine policy, such as the need for and timing of booster doses. We aimed to systematically review the evidence for the duration of protection of COVID-19 vaccines against various clinical outcomes, and to assess changes in the rates of breakthrough infection caused by the delta variant with increasing time since vaccination. METHODS: This study was designed as a systematic review and meta-regression. We did a systematic review of preprint and peer-reviewed published article databases from June 17, 2021, to Dec 2, 2021. Randomised controlled trials of COVID-19 vaccine efficacy and observational studies of COVID-19 vaccine effectiveness were eligible. Studies with vaccine efficacy or effectiveness estimates at discrete time intervals of people who had received full vaccination and that met predefined screening criteria underwent full-text review. We used random-effects meta-regression to estimate the average change in vaccine efficacy or effectiveness 1-6 months after full vaccination. FINDINGS: Of 13 744 studies screened, 310 underwent full-text review, and 18 studies were included (all studies were carried out before the omicron variant began to circulate widely). Risk of bias, established using the risk of bias 2 tool for randomised controlled trials or the risk of bias in non-randomised studies of interventions tool was low for three studies, moderate for eight studies, and serious for seven studies. We included 78 vaccine-specific vaccine efficacy or effectiveness evaluations (Pfizer-BioNTech-Comirnaty, n=38; Moderna-mRNA-1273, n=23; Janssen-Ad26.COV2.S, n=9; and AstraZeneca-Vaxzevria, n=8). On average, vaccine efficacy or effectiveness against SARS-CoV-2 infection decreased from 1 month to 6 months after full vaccination by 21·0 percentage points (95% CI 13·9-29·8) among people of all ages and 20·7 percentage points (10·2-36·6) among older people (as defined by each study, who were at least 50 years old). For symptomatic COVID-19 disease, vaccine efficacy or effectiveness decreased by 24·9 percentage points (95% CI 13·4-41·6) in people of all ages and 32·0 percentage points (11·0-69·0) in older people. For severe COVID-19 disease, vaccine efficacy or effectiveness decreased by 10·0 percentage points (95% CI 6·1-15·4) in people of all ages and 9·5 percentage points (5·7-14·6) in older people. Most (81%) vaccine efficacy or effectiveness estimates against severe disease remained greater than 70% over time. INTERPRETATION: COVID-19 vaccine efficacy or effectiveness against severe disease remained high, although it did decrease somewhat by 6 months after full vaccination. By contrast, vaccine efficacy or effectiveness against infection and symptomatic disease decreased approximately 20-30 percentage points by 6 months. The decrease in vaccine efficacy or effectiveness is likely caused by, at least in part, waning immunity, although an effect of bias cannot be ruled out. Evaluating vaccine efficacy or effectiveness beyond 6 months will be crucial for updating COVID-19 vaccine policy. FUNDING: Coalition for Epidemic Preparedness Innovations.

Integrating health services for HIV infection, diabetes and hypertension in sub-Saharan Africa: a cohort study.

BACKGROUND: HIV, diabetes and hypertension have a high disease burden in sub-Saharan Africa. Healthcare is organised in separate clinics, which may be inefficient. In a cohort study, we evaluated integrated management of these conditions from a single chronic care clinic. OBJECTIVES: To determined the feasibility and acceptability of integrated management of chronic conditions in terms of retention in care and clinical indicators. DESIGN AND SETTING: Prospective cohort study comprising patients attending 10 health facilities offering primary care in Dar es Salaam and Kampala. INTERVENTION: Clinics within health facilities were set up to provide integrated care. Patients with either HIV, diabetes or hypertension had the same waiting areas, the same pharmacy, were seen by the same clinical staff, had similar provision of adherence counselling and tracking if they failed to attend appointments. PRIMARY OUTCOME MEASURES: Retention in care, plasma viral load. FINDINGS: Between 5 August 2018 and 21 May 2019, 2640 patients were screened of whom 2273 (86%) were enrolled into integrated care (832 with HIV infection, 313 with diabetes, 546 with hypertension and 582 with multiple conditions). They were followed up to 30 January 2020. Overall, 1615 (71.1%)/2273 were female and 1689 (74.5%)/2266 had been in care for 6 months or more. The proportions of people retained in care were 686/832 (82.5%, 95% CI: 79.9% to 85.1%) among those with HIV infection, 266/313 (85.0%, 95% CI: 81.1% to 89.0%) among those with diabetes, 430/546 (78.8%, 95% CI: 75.4% to 82.3%) among those with hypertension and 529/582 (90.9%, 95% CI: 88.6 to 93.3) among those with multimorbidity. Among those with HIV infection, the proportion with plasma viral load <100 copies/mL was 423(88.5%)/478. CONCLUSION: Integrated management of chronic diseases is a feasible strategy for the control of HIV, diabetes and hypertension in Africa and needs evaluation in a comparative study.

Integrating HIV, diabetes and hypertension services in Africa: study protocol for a cluster randomised trial in Tanzania and Uganda.

INTRODUCTION: HIV programmes in sub-Saharan Africa are well funded but programmes for diabetes and hypertension are weak with only a small proportion of patients in regular care. Healthcare provision is organised from stand-alone clinics. In this cluster randomised trial, we are evaluating a concept of integrated care for people with HIV infection, diabetes or hypertension from a single point of care. METHODS AND ANALYSIS: 32 primary care health facilities in Dar es Salaam and Kampala regions were randomised to either integrated or standard vertical care. In the integrated care arm, services are organised from a single clinic where patients with either HIV infection, diabetes or hypertension are managed by the same clinical and counselling teams. They use the same pharmacy and laboratory and have the same style of patient records. Standard care involves separate pathways, that is, separate clinics, waiting and counselling areas, a separate pharmacy and separate medical records. The trial has two primary endpoints: retention in care of people with hypertension or diabetes and plasma viral load suppression. Recruitment is expected to take 6 months and follow-up is for 12 months. With 100 participants enrolled in each facility with diabetes or hypertension, the trial will provide 90% power to detect an absolute difference in retention of 15% between the study arms (at the 5% two-sided significance level). If 100 participants with HIV infection are also enrolled in each facility, we will have 90% power to show non-inferiority in virological suppression to a delta=10% margin (ie, that the upper limit of the one-sided 95% CI of the difference between the two arms will not exceed 10%). To allow for lost to follow-up, the trial will enrol over 220 persons per facility. This is the only trial of its kind evaluating the concept of a single integrated clinic for chronic conditions in Africa. ETHICS AND DISSEMINATION: The protocol has been approved by ethics committee of The AIDS Support Organisation, National Institute of Medical Research and the Liverpool School of Tropical Medicine. Dissemination of findings will be done through journal publications and meetings involving study participants, healthcare providers and other stakeholders. TRIAL REGISTRATION NUMBER: ISRCTN43896688.

Evaluation of post-introduction COVID-19 vaccine effectiveness: Summary of interim guidance of the World Health Organization.

Phase 3 randomized-controlled trials have provided promising results of COVID-19 vaccine efficacy, ranging from 50 to 95% against symptomatic disease as the primary endpoints, resulting in emergency use authorization/listing for several vaccines. However, given the short duration of follow-up during the clinical trials, strict eligibility criteria, emerging variants of concern, and the changing epidemiology of the pandemic, many questions still remain unanswered regarding vaccine performance. Post-introduction vaccine effectiveness evaluations can help us to understand the vaccine's effect on reducing infection and disease when used in real-world conditions. They can also address important questions that were either not studied or were incompletely studied in the trials and that will inform evolving vaccine policy, including assessment of the duration of effectiveness; effectiveness in key subpopulations, such as the very old or immunocompromised; against severe disease and death due to COVID-19; against emerging SARS-CoV-2 variants of concern; and with different vaccination schedules, such as number of doses and varying dosing intervals. WHO convened an expert panel to develop interim best practice guidance for COVID-19 vaccine effectiveness evaluations. We present a summary of the interim guidance, including discussion of different study designs, priority outcomes to evaluate, potential biases, existing surveillance platforms that can be used, and recommendations for reporting results.

Global diarrhoea-associated mortality estimates and models in children: Recommendations for dataset and study selection.

BACKGROUND: Multiple factors contribute to variation in disease burden, including the type and quality of data, and inherent properties of the models used. Understanding how these factors affect mortality estimates is crucial, especially in the context of public health decision making. We examine how the quality of the studies selected to provide mortality data, influence estimates of burden and provide recommendations about the inclusion of studies and datasets to calculate mortality estimates. METHODS: To determine how mortality estimates are affected by the data used to generate model outputs, we compared the studies used by The Institute of Health Metrics and Evaluation (IHME) and Maternal and Child Epidemiology Estimation (MCEE) modelling groups to generate enterotoxigenic Escherichia coli (ETEC) and Shigella-associated mortality estimates for 2016. Guided by an expert WHO Working Group, we applied a modified Newcastle-Ottawa Scale (NOS) to evaluate the quality of studies used by both modelling groups. RESULTS: IHME and MCEE used different sets of ETEC and Shigella studies in their models and the majority of studies were high quality. The distribution of the NOS scores was similar between the two modelling groups. We observed an overrepresentation of studies from some countries in SEAR, AFR and WPR compared to other WHO regions. CONCLUSION: We identified key differences in study inclusion and exclusion criteria used by IHME and MCEE and discuss their impact on datasets used to generate diarrhoea-associated mortality estimates. Based on these observations, we provide a set of recommendations for future estimates of mortality associated with enteric diseases.

Novel vaccine safety issues and areas that would benefit from further research.

Vaccine licensure requires a very high safety standard and vaccines routinely used are very safe. Vaccine safety monitoring prelicensure and postlicensure enables continual assessment to ensure the benefits outweigh the risks and, when safety problems arise, they are quickly identified, characterised and further problems prevented when possible. We review five vaccine safety case studies: (1) dengue vaccine and enhanced dengue disease, (2) pandemic influenza vaccine and narcolepsy, (3) rotavirus vaccine and intussusception, (4) human papillomavirus vaccine and postural orthostatic tachycardia syndrome and complex regional pain syndrome, and (5) RTS,S/adjuvant system 01 malaria vaccine and meningitis, cerebral malaria, female mortality and rebound severe malaria. These case studies were selected because they are recent and varied in the vaccine safety challenges they elucidate. Bringing these case studies together, we develop lessons learned that can be useful for addressing some of the potential safety issues that will inevitably arise with new vaccines.

Key criteria for the ethical acceptability of COVID-19 human challenge studies: Report of a WHO Working Group.

This report of the WHO Working Group for Guidance on Human Challenge Studies in COVID-19 outlines ethical standards for COVID-19 challenge studies. It includes eight Key Criteria related to scientific justification, risk-benefit assessment, consultation and engagement, co-ordination of research, site selection, participant selection, expert review, and informed consent. The document aims to provide comprehensive guidance to scientists, research ethics committees, funders, policymakers, and regulators in deliberations regarding SARS-CoV-2 challenge studies by outlining criteria that would need to be satisfied in order for such studies to be ethically acceptable.

Upconversion detection of 1.25 Gb/s mid-infrared telecommunications using a silicon avalanche photodiode.

With an ever-increasing interest in secure and reliable free-space optical communication, upconversion detectors enabled through nonlinear optical processes are an attractive route to transmitting data as a mid-infrared signal. This spectral region is known to have a higher transmissivity through the atmosphere. In this work, we present an upconversion scheme for detection in the silicon absorption band using magnesium-oxide doped periodically poled lithium niobate to generate 21 mW of a 3.4 µm signal from commercial laser sources using a difference frequency generation process. Following a further nonlinear frequency conversion, via sum-frequency generation, the resulting signal at 809 nm is detected. We achieve >50 µW of signal and bit error rates of 10-7 from a single-pass nonlinear conversion for both the transmitter and receiver systems without the need for additional optical amplifiers at the receiving end. The error rates due to potentially reduced laser powers at the receiver end are investigated and laser noise transfer through our system is discussed.

213 nm laser written waveguides in Ge-doped planar silica without hydrogen loading.

In this paper we present the first example of waveguides fabricated by UV writing in non-hydrogen loaded Ge-doped planar silica with 213 nm light. Single mode waveguides were fabricated and the numerical apertures and mode field diameters were measured for a range of writing fluences. A peak index change of 5.3 x 10-3 was inferred for the waveguide written with 70 kJ cm-2. The refractive index change is sufficient to match the index structure of standard optical fiber. Uniformity of the written structures was measured and a propagation loss of 0.39 ± 0.03 dB cm-1 was determined through cutback measurements.

CW demonstration of SHG spectral narrowing in a PPLN waveguide generating 2.5 W at 780†nm.

Periodically poled lithium niobate (PPLN) waveguides are a proven and popular means for efficient wavelength conversion. However, conventional PPLN waveguides typically have small mode field diameters (MFD) (≲6 µm) or significant insertion and/or propagation losses, limiting their ability to operate at multi-watt power levels. In this work we utilise zinc indiffused PPLN ridge waveguides that have a larger MFD, favourable pump/SHG modal overlap, and low insertion losses. Here for the first time, we have demonstrated continuous wave (CW) spectral narrowing from a PPLN waveguide, both with high efficiency and multi-watt second harmonic generation (SHG). 2.5 W of 780 nm has been produced by SHG of an amplified 1560 nm telecom laser with a device efficiency of 58% in a 4.0-cm long ridge waveguide. We have modelled conversion efficiency and applied experimentally measured waveguide parameters to show excellent agreement to the SHG spectra. Spectral narrowing of the full width half maximum (FWHM) of 35.7% has been measured as the nonlinear drive is increased. This work demonstrates that single-pass, multi-watt, CW SHG at 780 nm is feasible from our PPLN waveguide in the large conversion regime.

Highly-chirped Bragg gratings for integrated silica spectrometers.

A blazed chirped Bragg grating in a planar silica waveguide device was used to create an integrated diffractive element for a spectrometer. The grating diffracts light from a waveguide and creates a wavelength dependent focus in a manner similar to a bulk diffraction grating spectrometer. An external imaging system is used to analyse the light, later device iterations plan to integrate detectors to make a fully integrated spectrometer. Devices were fabricated with grating period chirp rates in excess of 100 nm mm-1, achieving a focal length of 5.5 mm. Correction of coma aberrations resulted in a device with a footprint of 20 mm×10 mm, a peak FWHM resolution of 1.8 nm, a typical FWHM resolution of 2.6 nm and operating with a 160 nm bandwidth centered at 1550 nm.