Browsing by Author "Biraro, Sam"
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Item Acceptability and Predictors of Uptake of Anti-Retroviral Pre-Exposure Prophylaxis (Prep) among Fishing Communities in Uganda: A Cross-Sectional Discrete Choice Experiment Survey(AIDS and behavior, 2019) Kuteesa, Monica O.; Quaife, Mathew; Biraro, Sam; Katumba, Kenneth R.; Seeley, Janet; Kamali, Anatoli; Nakanjako, DamalieWe used a discrete choice experiment to assess the acceptability and potential uptake of HIV pre-exposure prophylaxis (PrEP) among 713 HIV-negative members of fishing communities in Uganda. Participants were asked to choose between oral pill, injection, implant, condoms, vaginal ring (women), and men circumcision. Product attributes were HIV prevention effectiveness, sexually transmitted infection (STI) prevention, contraception, waiting time, and secrecy of use. Data were analysed using mixed multinomial logit and latent class models. HIV prevention effectiveness was viewed as the most important attribute. Both genders preferred oral PrEP. Women least preferred the vaginal ring and men the implant. Condom use was predicted to decrease by one third among men, and not to change amongst women. Oral PrEP and other new prevention technologies are acceptable among fishing communities and may have substantial demand. Future work should explore utility of multiple product technologies that combine contraception with HIV and other STI prevention.Item Age-Specific Mortality Patterns in HIV-Infected Individuals: A Comparative Analysis of African Community Study Data(Aids, 2007) Zaba, Basia; Marston, Milly; Crampin, Amelia C.; Isingo, Raphael; Biraro, Sam; Ba¨rnighausen, Till; Lopman, Ben; Lutalo, Tom; Glynn, Judith R.; Todd, JimDescribe age-specific mortality patterns of HIV-infected adults in African communities before introduction of HAART.Mortality data (deaths and person-years observed) for HIV-positive subjects aged 15–65 from six African community studies in five different countries were pooled, combining information from 1793 seroconverters and 8534 HIV positive when first tested. Age-specific mortality hazards were modelled using parametric regression based on the Weibull distribution, to investigate effects of sex, and site-specific measures of mean age at incidence, crude mortality rate of uninfected, and measures of epidemic maturity.The combined studies yielded a total of 31 777 person-years of observation for HIV-positive subjects, during which time 2602 deaths were recorded. Mortality rates rose almost linearly with age, from below 50/1000 at ages < 20 years, up to 150/1000 at 50 years +. There was no significant difference between men and women in level or age pattern of mortality. Weibull regression analysis suggested that intersite variation could be explained by HIV prevalence trend, and by the ratio of HIV proportional mortality to current HIV prevalence. A model representation was constructed with a common age pattern of mortality, but allowing the level to be adjusted by specifying HIV prevalence indicators.The linear age trend of mortality in HIV-infected populations was satisfactorily represented by a Weibull function providing a parametric model adaptable for representing different levels of HIV-related mortality. This model might be simpler to use in demographic projections of HIV-affected populations than models based on survival post-infection.Item Coronavirus Disease 2019 (COVID-19) Mitigation Efforts and Testing During an In-Person Training Event—Uganda, 12–29 October 2020(Clinical Infectious Diseases, 2021) Laws, Rebecca L.; Biraro, Sam; Kirungi, Wilford; Gianetti, Brittany; Aibo, Dorothy; Awor, Anna C.; West, Christine; Sachathep, Karampreet K.; Kiyingi, Herbert; Ward, Jennifer; Mwangi, Christina; Nkurunziza, PeterViral load monitoring (VLM) to identify individuals failing antiretroviral therapy (ART) is not widely available in resource-limited settings. We compared the genotypic resistance patterns between clients with VLM versus immunological monitoring (IM).Between 2004–2008, 559 ART naïve clients were enrolled in a prospective cohort, initiated on ART, and monitored with viral load (VL) and CD4+ cell counts every 6 months (VLM group). From February 2008 through June 2009, 998 clients on ART for 36–40 months (corresponding to the follow-up time of the VLM group) at the same clinic and monitored with CD4+ cell counts every 6 months were recruited into a cross sectional study (IM group). Samples from VLM clients at 12, 24 and 36 months and IM clients at 36–40 months with VL > 2000 copies/ml underwent genotypic drug resistance testing.Baseline characteristics were similar. Virologic failure (VL > 400 copies/ml) at 12, 24 and 36 months in the VLM group were 12%, 6% and 8% respectively, and in the IM group 10% at 36–40 months. Samples from 39 VLM and 70 IM clients were genotyped. 23/39 (59%) clients in the VLM group (at 12, 24 or 36 months) compared to 63/70 (90%) in the IM group, (P < 0.0001) had at least 1 non-nucleoside reverse transcriptase mutation. 19/39 (49%) of VLM clients had an M184V mutation compared to 61/70 (87%) in the IM group (P < 0.0001). Only 2/39 (5%) of VLM clients developed thymidine analogue mutations compared to 34/70 (49%) of IM clients (P < 0.0001).Routine VL monitoring reduced the rate of accumulated genotypic resistance to commonly used ART in Uganda.Item Estimating Incidence from Prevalence in Generalised HIV Epidemics: Methods and Validation(PLoS medicine, 2008) Hallett, Timothy B.; Zaba, Basia; Todd, Jim; Lopman, Ben; Mwita, Wambura; Biraro, Sam; Gregson, SimonHIV surveillance of generalised epidemics in Africa primarily relies on prevalence at antenatal clinics, but estimates of incidence in the general population would be more useful. Repeated cross-sectional measures of HIV prevalence are now becoming available for general populations in many countries, and we aim to develop and validate methods that use these data to estimate HIV incidence.Two methods were developed that decompose observed changes in prevalence between two serosurveys into the contributions of new infections and mortality. Method 1 uses cohort mortality rates, and method 2 uses information on survival after infection. The performance of these two methods was assessed using simulated data from a mathematical model and actual data from three community-based cohort studies in Africa. Comparison with simulated data indicated that these methods can accurately estimates incidence rates and changes in incidence in a variety of epidemic conditions. Method 1 is simple to implement but relies on locally appropriate mortality data, whilst method 2 can make use of the same survival distribution in a wide range of scenarios. The estimates from both methods are within the 95% confidence intervals of almost all actual measurements of HIV incidence in adults and young people, and the patterns of incidence over age are correctly captured.It is possible to estimate incidence from cross-sectional prevalence data with sufficient accuracy to monitor the HIV epidemic. Although these methods will theoretically work in any context, we have able to test them only in southern and eastern Africa, where HIV epidemics are mature and generalised. The choice of method will depend on the local availability of HIV mortality data.Item Estimating ‘net’ HIV-related Mortality and the Importance of Background Mortality Rates(AIDS, 2007) Marston, Milly; Todd, Jim; Glynn, Judith R.; Nelson, Kenrad E.; Rangsin, Ram; Lutalo, Tom; Urassa, Mark; Biraro, Sam; Paal, Lieve Van der; Sonnenberg, Pam; Żaba, BasiaTo estimate mortality directly attributable to HIV in HIV-infected adults in low and middle income countries and discuss appropriate methodology.Illustrative analysis of pooled data from six studies across sub-Saharan Africa and Thailand with data on individuals with known dates of seroconversion to HIV.Five of the studies also had data from HIV-negative subjects and one had verbal autopsies. Data for HIV-negative cohorts were weighted by the initial age and sex distribution of the seroconverters. Using the survival of the HIV-negative group to represent the background mortality, net survival from HIV was calculated for the seroconverters using competing risk methods. Mortality from all causes and ‘net’ mortality were modelled using piecewise exponential regression. Alternative approaches are explored in the dataset without information on mortality of uninfected individuals.The overall effect of the net mortality adjustment was to increase survivorship proportionately by 2 to 5% at 6 years post-infection. The increase ranged from 2% at ages 15–24 to 22% in those 55 and over. Mortality rate ratios between sites were similar to corresponding ratios for all-cause mortality.Differences between HIV mortality in different populations and age groups are not explained by differences in background mortality, although this does appear to contribute to the excess at older ages. In the absence of data from uninfected individuals in the same population, model life tables can be used to calculate background rates.Item Food Insecurity and the Risk of HIV Acquisition: Findings from Populationbased Surveys in Six Sub-Saharan African Countries (2016-2017)(medRxiv., 2021) Low, Andrea; Gummerson, Elizabeth; Schwitters, Amee; Bonifacio, Rogerio; Teferi, Mekleet; Mutenda, Nicholus; Ayton, Sarah; Juma, James; Ahpoe, Claudia; Ginindza, Choice; Patel, Hetal; Biraro, Sam; Sachathep, Karam; Hakim, Avi; Barradas, Danielle T.; Hassani, Ahmed Saadani; Kirungi, Wilford; Jackson, Keisha; Goeke, Leah H.; Philip, Neena M.; Mulenga, Lloyd; Ward, Jennifer; Hong, Steven; Rutherford, George; Findley, SallyFood insecurity has a bidirectional relationship with HIV infection, with hunger driving compensatory risk behaviors, while infection can increase poverty. We used a laboratory recency assay to estimate the timing of HIV infection vis-à-vis the timing of severe food insecurity (SFI).Data from population-based surveys in Zambia, Eswatini, Lesotho, Uganda, and Tanzania and Namibia were used. We defined SFI as having no food ≥three times in the past month. Recent HIV infection was identified using the HIV-1 LAg avidity assay, with a viral load (>1000 copies/ml) and no detectable antiretrovirals indicating an infection in the past 6 months. Logistic regression was conducted to assess correlates of SFI. Poisson regression was conducted on pooled data, adjusted by country to determine the association of SFI with recent HIV infection and risk behaviors, with effect heterogeneity evaluated for each country. All analyses were done using weighted data.Of 112,955 participants aged 15-59, 10.3% lived in households reporting SFI. SFI was most common in urban, woman-headed households. Among women and not men, SFI was associated with a two-fold increase in risk of recent HIV infection (adjusted relative risk [aRR] 2.08, 95% CI 1.09-3.97), with lower risk in high prevalence countries (Eswatini and Lesotho). SFI was associated with transactional sex (aRR 1.28, 95% CI 1.17-1.41), a history of forced sex (aRR 1.36, 95% CI 1.11-1.66), and condom-less sex with a partner of unknown or positive HIV status (aRR 1.08, 95% CI 1.02-1.14) in all women, and intergenerational sex (partner ≥10 years older) in women aged 15-24 (aRR 1.23, 95% CI 1.03-1.46), although this was heterogeneous. Recent receipt of food support was protective (aRR 0.36, 95% CI 0.14-0.88).SFI increased risk for HIV acquisition in women by two-fold. Worsening food scarcity due to climactic extremes could imperil HIV epidemic control.Item The General Population Cohort in Rural South Western Uganda: A Platform for Communicable and Non-Communicable Disease Studies(International journal of epidemiology, 2013) Asiki, Gershim; Murphy, Georgina; Miiro, Jessica Nakiyingi; Seeley, Janet; Nsubuga, Rebecca N.; Karabarinde, Alex; Waswa, Laban; Biraro, Sam; Kasamba, Ivan; Pomilla, Cristina; Maher, Dermot; Young, Elizabeth H; Kamali, Anatoli; Sandhu, Manjinder SThe General Population Cohort (GPC) was set up in 1989 to examine trends in HIV prevalence and incidence, and their determinants in rural south-western Uganda. Recently, the research questions have included the epidemiology and genetics of communicable and non-communicable diseases (NCDs) to address the limited data on the burden and risk factors for NCDs in sub-Saharan Africa. The cohort comprises all residents (52% aged ≥13years, men and women in equal proportions) within one-half of a rural sub-county, residing in scattered houses, and largely farmers of three major ethnic groups. Data collected through annual surveys include; mapping for spatial analysis and participant location; census for individual socio-demographic and household socioeconomic status assessment; and a medical survey for health, lifestyle and biophysical and blood measurements to ascertain disease outcomes and risk factors for selected participants. This cohort offers a rich platform to investigate the interplay between communicable diseases and NCDs. There is robust infrastructure for data management, sample processing and storage, and diverse expertise in epidemiology, social and basic sciences. For any data access enquiries you may contact the director, MRC/UVRI, Uganda Research Unit on AIDS by email to mrc@mrcuganda.org or the corresponding author.Item Global Health Leadership Training in Resource-Limited Settings: A Collaborative Approach by Academic Institutions and Local Health Care Programs in Uganda(Human Resources for Health, 2015) Nakanjako, Damalie; Namagala, Elizabeth; Semeere, Aggrey; Kigozi, Joanitor; Sempa, Joseph; Ddamulira, John Bosco; Katamba, Achilles; Biraro, Sam; Naikoba, Sarah; Mashalla, Yohana; Farquhar, Carey; Afya Bora Consortium members; Sewankambo, NelsonDue to a limited health workforce, many health care providers in Africa must take on health leadership roles with minimal formal training in leadership. Hence, the need to equip health care providers with practical skills required to lead high-impact health care programs. In Uganda, the Afya Bora Global Health Leadership Fellowship is implemented through the Makerere University College of Health Sciences (MakCHS) and her partner institutions. Lessons learned from the program, presented in this paper, may guide development of in-service training opportunities to enhance leadership skills of health workers in resource-limited settings.The Afya Bora Consortium, a consortium of four African and four U.S. academic institutions, offers 1-year global health leadership-training opportunities for nurses and doctors. Applications are received and vetted internationally by members of the consortium institutions in Botswana, Kenya, Tanzania, Uganda, and the USA. Fellows have 3 months of didactic modules and 9 months of mentored field attachment with 80% time dedicated to fellowship activities. Fellows’ projects and experiences, documented during weekly mentor-fellow meetings and monthly mentoring team meetings, were compiled and analyzed manually using pre-determined themes to assess the effect of the program on fellows’ daily leadership opportunities.Between January 2011 and January 2015, 15 Ugandan fellows (nine doctors and six nurses) participated in the program. Each fellow received 8 weeks of didactic modules held at one of the African partner institutions and three online modules to enhance fellows’ foundation in leadership, communication, monitoring and evaluation, health informatics, research methodology, grant writing, implementation science, and responsible conduct of research. In addition, fellows embarked on innovative projects that covered a wide spectrum of global health challenges including critical analysis of policy formulation and review processes, bottlenecks in implementation of national HIV early infant diagnosis and prevention of mother-to-child HIV-transmission programs, and use of routine laboratory data about antibiotic resistance to guide updates of essential drug lists.In-service leadership training was feasible, with ensured protected time for fellows to generate evidence-based solutions to challenges within their work environment. With structured mentorship, collaborative activities at academic institutions and local health care programs equipped health care providers with leadership skills.Item Increasing incidence of pregnancy among women receiving HIV care and treatment at a large urban facility in western Uganda(Reproductive health, 2014) Kabami, Jane; Turyakira, Eleanor; Biraro, Sam; Bajunirwe, FrancisAntiretroviral treatment restores physical functioning and may have an impact on fertility desires. Counseling is given to HIV positive women to create awareness and to provide information on pregnancy and delivery. The purpose of this study was to determine the incidence of pregnancy and factors that predict pregnancy among women of reproductive age receiving HIV care and treatment at a large urban center in western Uganda.We conducted a retrospective cohort study using routinely collected data at the Immune Suppression (ISS) Clinic of Mbarara Regional Referral Hospital located in Mbarara District, western Uganda collected between January 2006 and June 2010. Women aged 15 to 50 years were eligible for analysis. The primary outcome was incidence of pregnancy calculated as number of pregnancies per 1000 person years (PY). Data was analyzed by calendar year and year of enrolment and used survival analysis to determine the predictors of pregnancy.A total of 3144 women were included with a median follow up of 12.5 months. The overall incidence rate was 90.7 pregnancies per 1000 person years. Incidence increased from 29.8 pregnancies per 1000 PY in 2006 to 122 pregnancies per 1000 PY in 2010 (p < 0.001). Significant predictors for pregnancy were younger age (HR 10.96 95% CI 3.22-37.2), married (HR 2.09 95% CI 1.69-2.64) and single (HR 1.95 95% CI 1.34-2.84) compared to widowed or separated, primary education (HR 1.65 95% CI 1.02-2.66), not knowing the HIV status of the spouse (HR 1.46, 95%CI 1.13-1.93) compared to knowing. The use of family planning (HR 0.23 95% CI 0.18- 0.30) and an increase in CD4 count between baseline and most recent count were protective against pregnancy. ART use was not a significant predictor.Incidence of pregnancy among women receiving routine HIV care and treatment has increased and is almost comparable to that in the general population. Thus routine HIV care should integrate reproductive health needs for these women.Item Model-Based Small Area Estimation Methods and Precise District-Level HIV Prevalence Estimates in Uganda(PloS one, 2021) Ouma, Joseph; Jeffery, Caroline; Awor, Colletar Anna; Muruta, Allan; Musinguzi, Joshua; Wanyenze, Rhoda K.; Biraro, Sam; Levin, Jonathan; Valadez, Joseph J.Model-based small area estimation methods can help generate parameter estimates at the district level, where planned population survey sample sizes are not large enough to support direct estimates of HIV prevalence with adequate precision. We computed district-level HIV prevalence estimates and their 95% confidence intervals for districts in Uganda.Our analysis used direct survey and model-based estimation methods, including Fay-Herriot (area-level) and Battese-Harter-Fuller (unit-level) small area models. We used regression analysis to assess for consistency in estimating HIV prevalence. We use a ratio analysis of the mean square error and the coefficient of variation of the estimates to evaluate precision. The models were applied to Uganda Population-Based HIV Impact Assessment 2016/2017 data with auxiliary information from the 2016 Lot Quality Assurance Sampling survey and antenatal care data from district health information system datasets for unit-level and area-level models, respectively.Estimates from the model-based and the direct survey methods were similar. However, direct survey estimates were unstable compared with the model-based estimates. Area-level model estimates were more stable than unit-level model estimates. The correlation between unit-level and direct survey estimates was (β1 = 0.66, r2 = 0.862), and correlation between area-level model and direct survey estimates was (β1 = 0.44, r2 = 0.698). The error associated with the estimates decreased by 37.5% and 33.1% for the unit-level and area-level models, respectively, compared to the direct survey estimates.Although the unit-level model estimates were less precise than the area-level model estimates, they were highly correlated with the direct survey estimates and had less standard error associated with estimates than the area-level model. Unit-level models provide more accurate and reliable data to support local decision-making when unit-level auxiliary information is available.Item The proportion of HIV incidence due to unsafe injections, unsafe blood transfusions and mother to child transmission in rural Masaka, Uganda(Proc Natl Acad Sci USA, 2007) White, Richard G.; Kedhar, Anusha; Orroth, Kate K.; Biraro, Sam; Baggaley, Rebecca; Whitworth, Jimmy; Korenromp, Eline L.; Boily, Marie-Claude; Hayes, Richard J.To estimate the proportion of all-age HIV incidence attributable to unsafe injections, unsafe blood transfusions and mother-to-child transmission (MTCT) in rural Masaka, Uganda, during the early 1990s.Observed HIV incidence and prevalence, and injection and transfusion rates were calculated using data from a general population cohort study in Masaka (1989-2000). Injection and blood transfusion safety was estimated from observational surveys within Uganda and East Africa. HIV transmission probabilities were estimated from scientific literature review. Model: A model was used to estimate the incidence via unsafe injections (assuming random or age-dependent mixing of injection equipment) and unsafe transfusions. An age-specific model of fertility was used to estimate the incidence via MTCT.Unsafe injections accounted for 5.1% [95% uncertainty bounds (UB) 0.0-10.3] or 12.4% [95%UB 0.0-27.0] of all-age HIV incidence in the random and age-dependent mixing scenarios respectively. Unsafe blood transfusions accounted for 0.4% [95%UB 0.2-0.6], and MTCT accounted for 23.4% [95%UB 15.3-31.5]. 64-71% of all-age HIV incidence was left unexplained by these three routes of transmission. Among 13+ year olds, unsafe injections accounted for 1.4% [95%UB 0.0-2.8] or 12.1% [95%UB 0.0- 26.5] of HIV incidence in the random and age-dependent mixing scenarios respectively. Unsafe blood transfusions accounted for 0.3% [95%UB 0.1-0.4], leaving 87.6-98.3% of HIV incidence left unexplained by these three routes of transmission.This study does not support the hypothesis that unsafe injections or blood transfusions played a major role in HIV transmission in this population during the study period. The safety of both injections and transfusions should be improved to reduce HIV transmission via these routes still further, but particular efforts should be made to reduce the larger proportion of HIV transmission due to MTCT, and among 13+ year olds, the unexplained incidence, presumably primarily due to sexual transmission.Item Quantifying HIV-1 Transmission due to Contaminated Injections(Proceedings of the National Academy of Sciences, 2007) White, Richard G.; Cooper, Ben S.; Kedhar, Anusha; Biraro, SamAssessments of the importance of different routes of HIV-1 (HIV) transmission are vital for prioritization of control efforts. Lack of consistent direct data and large uncertainty in the risk of HIV transmission from HIV-contaminated injections has made quantifying the proportion of transmission caused by contaminated injections in sub-Saharan Africa difficult and unavoidably subjective. Depending on the risk assumed, estimates have ranged from 2.5% to 30% or more. We present a method based on an age-structured transmission model that allows the relative contribution of HIV-contaminated injections, and other routes of HIV transmission, to be robustly estimated, both fully quantifying and substantially reducing the associated uncertainty. To do this, we adopt a Bayesian perspective, and show how prior beliefs regarding the safety of injections and the proportion of HIV incidence due to contaminated injections should, in many cases, be substantially modified in light of age-stratified incidence and injection data, resulting in improved (posterior) estimates. Applying the method to data from rural southwest Uganda, we show that the highest estimates of the proportion of incidence due to injections are reduced from 15.5% (95% credible interval) (0.7%, 44.9%) to 5.2% (0.5%, 17.0%) if random mixing is assumed, and from 14.6% (0.7%, 42.5%) to 11.8% (1.2%, 32.5%) under assortative mixing. Lower, and more widely accepted, estimates remain largely unchanged, between 1% and 3% (0.1–6.3%). Although important uncertainty remains, our analysis shows that in rural Uganda, contaminated injections are unlikely to account for a large proportion of HIV incidence. This result is likely to be generalizable to many other populations in sub-Saharan Africa.Item Unawareness of HIV Infection Among Men Aged 15–59 Years in 13 Sub-Saharan African Countries: Findings From the Population-Based HIV Impact Assessments, 2015–2019(JAIDS Journal of Acquired Immune Deficiency Syndromes, 2021) West, Christine A.; Chang, Gregory C.; Currie, Dustin W.; Bray, Rachel; Biribonwoha, Harriet Nuwagaba; Kingwara, Leonard; Remera, Eric; Rwibasira, Gallican N.; Mugisha, Veronicah; Kirungi, Wilford L.; Biraro, Sam; Mugurungi, OwenIdentifying men living with HIV in sub-Saharan Africa (SSA) is critical to end the epidemic. We describe the underlying factors of unawareness among men aged 15–59 years who ever tested for HIV in 13 SSA countries.Using pooled data from the nationally representative Population-based HIV Impact Assessments, we fit a log-binomial regression model to identify characteristics related to HIV positivity among HIV-positive unaware and HIV-negative men ever tested for HIV.A total of 114,776 men were interviewed and tested for HIV; 4.4% were HIV-positive. Of those, 33.7% were unaware of their HIV-positive status, (range: 20.2%–58.7%, in Rwanda and Cote d’Ivoire). Most unaware men reported they had ever received an HIV test (63.0%). Age, region, marital status, and education were significantly associated with HIV positivity. Men who had HIV-positive sexual partners (adjusted prevalence ratio [aPR]: 5.73; confidence interval [95% CI]: 4.13 to 7.95) or sexual partners with unknown HIV status (aPR: 2.32; 95% CI: 1.89 to 2.84) were more likely to be HIV-positive unaware, as were men who tested more than 12 months compared with HIV-negative men who tested within 12 months before the interview (aPR: 1.58; 95% CI: 1.31 to 1.91). Tuberculosis diagnosis and not being circumcised were also associated with HIV positivity.Targeting subgroups of men at risk for infection who once tested negative could improve yield of testing programs. Interventions include improving partner testing, frequency of testing, outreach and educational strategies, and availability of HIV testing where men are accessing routine health services.