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Emerging integrase strand transfer inhibitor drug resistance mutations among children and adults on ART in Tanzania: findings from a national representative HIV drug resistance survey. J Antimicrob Chemother 2023; 78:779-787. [PMID: 36680436 DOI: 10.1093/jac/dkad010] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 01/03/2023] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Despite the scale-up of ART and the rollout in Tanzania of dolutegravir, an integrase strand transfer inhibitor (INSTI), treatment success has not been fully realized. HIV drug resistance (HIVDR), including dolutegravir resistance, could be implicated in the notable suboptimal viral load (VL) suppression among HIV patients. OBJECTIVES To determine the prevalence and patterns of acquired drug resistance mutations (DRMs) among children and adults in Tanzania. METHODS A national cross-sectional HIVDR survey was conducted among 866 children and 1173 adults. Genotyping was done on dried blood spot and/or plasma of participants with high HIV VL (≥1000 copies/mL). HIV genes (reverse transcriptase, protease and integrase) were amplified by PCR and directly sequenced. The Stanford HIVDR Database was used for HIVDR interpretation. RESULTS HIVDR genotyping was performed on blood samples from 137 participants (92 children and 45 adults) with VL ≥ 1000 copies/mL. The overall prevalence of HIV DRMs was 71.5%, with DRMs present in 78.3% of children and 57.8% of adults. Importantly, 5.8% of participants had INSTI DRMs including major DRMs: Q148K, E138K, G118R, G140A, T66A and R263K. NNRTI, NRTI and PI DRMs were also detected in 62.8%, 44.5% and 8% of participants, respectively. All the participants with major INSTI DRMs harboured DRMs targeting NRTI backbone drugs. CONCLUSIONS More than 7 in 10 patients with high HIV viraemia in Tanzania have DRMs. The early emergence of dolutegravir resistance is of concern for the efficacy of the Tanzanian ART programme.
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Designing for two: How enhancing human-centered design with behavioral nudges unlocked breakthroughs to promote young women's psychological safety and access to reproductive care in Tanzania. Soc Sci Med 2023; 320:115683. [PMID: 36709692 PMCID: PMC10798268 DOI: 10.1016/j.socscimed.2023.115683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 01/11/2023] [Accepted: 01/13/2023] [Indexed: 01/16/2023]
Abstract
Adolescent girls and young women (AGYW; ages 15-24) in sub-Saharan Africa face many barriers to accessing preventive sexual and reproductive health (SRH) services. We drew upon the strengths of two complementary approaches, human-centered design and behavioral economics, to craft a holistic, highly-tailored, and empathetic intervention to motivate AGYW to seek contraception and HIV self-test kits at community drug shops. To encourage engagement, we embedded "nudge" strategies at different opportunity points (uncovered during our design research) along the care-seeking and service delivery journey. Our Malkia Klabu intervention is a loyalty program designed to enhance drug shops' role as SRH providers through which AGYW earned punches for shop purchases redeemable for small prizes; free SRH products could be requested at any time. From our 4-month pilot in Shinyanga, Tanzania, we assess the extent to which different behavioral nudge strategies motivated behaviors as predicted by synthesizing findings from (1) in-depth interviews with AGYW and shopkeepers, (2) shop program records, (3) shop observations, and (4) customer exit surveys. Overall, we find that AGYW and shopkeepers were motivated by many intervention features as intended and consistent with hypothesized mechanisms. We found strong evidence of social norms for helping to spread awareness of Malkia Klabu among peers, prize incentives for drawing AGYW back to shops, and the opt-out default membership gift of an HIV self-test kit for encouraging testing uptake and exploration of contraceptives. Shopkeepers in both arms noted increased community status from distributing HIV self-testing kits (ego). Malkia Klabu shopkeepers experienced increased customer traffic and business revenues (incentives), which reduced shopkeepers' gatekeeping tendencies and earned them additional recognition as champions of AGYW well-being. Integrating human-centered design and behavioral economics was effective for developing an innovative and effective intervention that simultaneously met the different needs of economic actors in support of public health priorities.
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HIV virologic response, patterns of drug resistance mutations and correlates among adolescents and young adults: A cross-sectional study in Tanzania. PLoS One 2023; 18:e0281528. [PMID: 36821538 PMCID: PMC9949668 DOI: 10.1371/journal.pone.0281528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 01/25/2023] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND The emergence of HIV drug resistance mutations (DRMs) is of significant threat to achieving viral suppression (VS) in the quest to achieve global elimination targets. We hereby report virologic outcomes and patterns of acquired DRMs and its associated factors among adolescents and young adults (AYA) from a broader HIV drug resistance surveillance conducted in Tanzania. METHODS Data of AYA was extracted from a cross-sectional study conducted in 36 selected facilities using a two-stage cluster sampling design. Dried blood spot (DBS) samples were collected and samples with a viral load (VL) ≥1000 copies/mL underwent genotyping for the HIV-1 pol gene. Stanford HIV database algorithm predicted acquired DRMs, Fisher's exact test and multivariable logistic regression assessed factors associated with DRMs and VS, respectively. FINDINGS We analyzed data of 578 AYA on antiretroviral therapy (ART) for 9-15 and ≥ 36 months; among them, 91.5% and 88.2% had VS (VL<1000copies/mL) at early and late time points, respectively. Genotyping of 64 participants (11.2%) who had VL ≥1000 copies/ml detected 71.9% of any DRM. Clinically relevant DRMs were K103N, M184V, M41L, T215Y/F, L210W/L, K70R, D67N, L89V/T, G118R, E138K, T66A, T97A and unexpectedly absent K65R. Participants on a protease inhibitor (PI) based regimen were twice as likely to not achieve VS compared to those on integrase strand transfer inhibitors (INSTI). The initial VL done 6 months after ART initiation of ≥1000copies/mL was the primary factor associated with detecting DRMs (p = .019). CONCLUSIONS VS amongst AYA is lower than the third UNAIDs target. Additionally, a high prevalence of ADR and high levels of circulating clinically relevant DRMs may compromise the long-term VS in AYA. Furthermore, the first VL result of ≥1000copies/ml after ART initiation is a significant risk factor for developing DRMs. Thus, strict VL monitoring for early identification of treatment failure and genotypic testing during any ART switch is recommended to improve treatment outcomes for AYA.
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Risks of Intimate Partner Violence for Women Living with HIV Receiving Cash Transfers: A Qualitative Study in Shinyanga, Tanzania. AIDS Behav 2023:10.1007/s10461-023-03997-2. [PMID: 36692608 DOI: 10.1007/s10461-023-03997-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2023] [Indexed: 01/25/2023]
Abstract
Cash transfers are increasingly used to motivate adherence to HIV care. However, evidence on cash transfers and intimate partner violence (IPV) is mixed and little is known about their safety for women living with HIV. We conducted in-depth interviews with women living with HIV who participated in a randomized trial providing 6 months of cash transfers (~$4.5 or $11 USD) conditional on HIV clinic attendance in Shinyanga, Tanzania to assess how receiving cash affects IPV and relationship dynamics. Eligible participants were 18-49 years, received cash transfers, and in a partnership at baseline. Data were analyzed in Dedoose using a combined inductive-deductive coding approach. 25 interviews were conducted between November 2019-February 2020. Women's employment was found to be a source of household tension and violence. None of the participants reported physical or sexual IPV in relation to cash transfers, however, some women experienced controlling behaviors or emotional violence including accusations and withholding of money, particularly those who were unemployed. Cash transfers were predominantly used for small household expenses and were not viewed as being substantial enough to shift the financial dynamic or balance of power within relationships. Our findings suggest that small, short-term cash transfers do not increase physical or sexual IPV for women living with HIV however can exacerbate controlling behaviors or emotional violence. Modest incentives used as a behavioral nudge to improve health outcomes may affect women differently than employment or larger cash transfers. Nonetheless, consultations with beneficiaries should be prioritized to protect women from potential IPV risks.
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Reaching Adolescent Girls and Young Women With HIV Self-Testing and Contraception at Girl-Friendly Drug Shops: A Randomized Trial in Tanzania. J Adolesc Health 2023; 72:64-72. [PMID: 36241492 PMCID: PMC9893895 DOI: 10.1016/j.jadohealth.2022.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 05/22/2022] [Accepted: 08/17/2022] [Indexed: 12/15/2022]
Abstract
PURPOSE We hypothesized that an intervention designed to create girl-friendly drug shops would increase access to sexual and reproductive health products and services among adolescent girls and young women (AGYW) (ages 15-24 years) in Tanzania. METHODS We conducted a four-month randomized trial at 20 drug shops in Shinyanga, Tanzania from August-December 2019 to determine if the Malkia Klabu ("Queen Club") intervention increased AGYW patronage and the provision of HIV self-testing (HIVST), contraception, and health facility referrals to AGYW (primary outcomes). Drug shops were randomized 1:1 to the intervention or comparison arm. All shops were provided with OraQuick HIVST kits to give to AGYW for free. Intervention shops implemented Malkia Klabu, a loyalty program for AGYW created using human-centered design through which AGYW could also access free contraception. We compared outcomes in intention-to-treat analyses using shop observations and shopkeeper records. RESULTS By endline, shops implementing Malkia Klabu had higher AGYW patronage than comparison shops (rate ratio: 4.4; 95% confidence interval: 2.0, 9.8). Intervention shops distributed more HIVST kits (median per shop: 130.5 vs. 58.5, P = .02) and contraceptives (325.5 vs. 7.0, P < .01) to AGYW and provided more referrals for HIV, family planning, or pregnancy services combined (3.5 vs. 0.5, P = .02) than comparison shops. DISCUSSION The Malkia Klabu intervention increased AGYW patronage and the provision of HIVST kits, contraception, and referrals to AGYW at drug shops, despite HIVST kits being freely available at all participating shops. Enhancing drug shops with girl-friendly services may be an effective strategy to reach AGYW with sexual and reproductive health services.
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Growth mindset, persistence, and self-efficacy in early adolescents: Associations with depression, anxiety, and externalising behaviours. Glob Public Health 2023; 18:2213300. [PMID: 37196667 DOI: 10.1080/17441692.2023.2213300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 05/08/2023] [Indexed: 05/19/2023]
Abstract
ABSTRACTGrowth mindset, persistence, and self-efficacy are important protective factors in understanding adolescent psychopathology, including depression, anxiety, and externalising behaviours. Previous studies have shown that dimensions of self-efficacy (academic, social, and emotional) have differential protective effects with mental health outcomes and these differences vary by sex. This study examines the dimensional mediation of self-efficacy from motivational mindsets on anxiety, depression, and externalising behaviours in a sample of early adolescents ages 10-11. Surveys were administered to participants to measure growth mindset and persistence on internalising and externalising symptoms. The Self-Efficacy Questionnaire for Children (SEQ-C) was used to measure domains of self-efficacy for mediation analysis. Multi-group structural equation modelling by sex indicated that structural paths were not invariant by sex. Significant direct effects were identified from persistence to externalising behaviours in boys, and significant direct effects were identified from growth mindset to depression in girls. In a sample of Tanzanian early adolescents, self-efficacy mediates the protective association between motivational mindsets on psychopathology. Higher academic self-efficacy was associated with reduced externalising problems in both boys and girls. Implications for adolescent programmes and future research are discussed.
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Associations Between Mobility, Food Insecurity, and Transactional Sex Among Women in Cohabitating Partnerships: An Analysis From 6 African Countries 2016-2017. J Acquir Immune Defic Syndr 2022; 90:388-398. [PMID: 35389376 PMCID: PMC9909688 DOI: 10.1097/qai.0000000000002995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/16/2022] [Indexed: 11/26/2022]
Abstract
BACKGROUND Mobile women are at risk of HIV infection in sub-Saharan Africa, although we lack evidence for HIV risk among women in mobile partnerships, especially in the context of household food insecurity, a growing concern in the region. SETTING Women aged 15-59 years with a cohabitating male partner who participated in population-based HIV impact assessment surveys in Eswatini, Lesotho, Namibia, Tanzania, Uganda, and Zambia. METHODS We evaluated the association between women's and their partner's mobility (being away from home for more than 1 month or staying elsewhere) and transactional sex (selling sex or receiving money or goods in exchange for sex). We examined associations for effect measure modification by food insecurity level in the household in the past month. We used survey-weighted logistic regression, pooled and by country, adjusting for individual, partner, and household-level variables. RESULTS Among women with a cohabitating male partner, 8.0% reported transactional sex, ranging from 2.7% in Lesotho to 13.4% in Uganda. Women's mobility [aOR 1.35 (95% CI: 1.08 to 1.68)], but not their partner's mobility [aOR 0.91 (0.74-1.12)], was associated with transactional sex. Food insecurity was associated with transactional sex independent of mobility [aOR 1.29 (1.10-1.52)]. Among those who were food insecure, mobility was not associated with increased odds of transactional sex. CONCLUSION Food insecurity and women's mobility each increased the odds of transactional sex. Because transactional sex is associated with HIV risk, prevention programs can address the needs of mobile and food-insecure women, including those in cohabitating relationships.
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Correcting for selection bias in HIV prevalence estimates: an application of sample selection models using data from population-based HIV surveys in seven sub-Saharan African countries. J Int AIDS Soc 2022; 25:e25954. [PMID: 35929226 PMCID: PMC9353488 DOI: 10.1002/jia2.25954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 06/09/2022] [Indexed: 11/25/2022] Open
Abstract
Introduction Population‐based biomarker surveys are the gold standard for estimating HIV prevalence but are susceptible to substantial non‐participation (up to 30%). Analytical missing data methods, including inverse‐probability weighting (IPW) and multiple imputation (MI), are biased when data are missing‐not‐at‐random, for example when people living with HIV more frequently decline participation. Heckman‐type selection models can, under certain assumptions, recover unbiased prevalence estimates in such scenarios. Methods We pooled data from 142,706 participants aged 15–49 years from nationally representative cross‐sectional Population‐based HIV Impact Assessments in seven countries in sub‐Saharan Africa, conducted between 2015 and 2018 in Tanzania, Uganda, Malawi, Zambia, Zimbabwe, Lesotho and Eswatini. We compared sex‐stratified HIV prevalence estimates from unadjusted, IPW, MI and selection models, controlling for household and individual‐level predictors of non‐participation, and assessed the sensitivity of selection models to the copula function specifying the correlation between study participation and HIV status. Results In total, 84.1% of participants provided a blood sample to determine HIV serostatus (range: 76% in Malawi to 95% in Uganda). HIV prevalence estimates from selection models diverged from IPW and MI models by up to 5% in Lesotho, without substantial precision loss. In Tanzania, the IPW model yielded lower HIV prevalence estimates among males than the best‐fitting copula selection model (3.8% vs. 7.9%). Conclusions We demonstrate how HIV prevalence estimates from selection models can differ from those obtained under missing‐at‐random assumptions. Further benefits include exploration of plausible relationships between participation and outcome. While selection models require additional assumptions and careful specification, they are an important tool for triangulating prevalence estimates in surveys with substantial missing data due to non‐participation.
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Predictors of loss to follow up from antiretroviral therapy among adolescents with HIV/AIDS in Tanzania. PLoS One 2022; 17:e0268825. [PMID: 35857796 PMCID: PMC9299289 DOI: 10.1371/journal.pone.0268825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 05/09/2022] [Indexed: 11/30/2022] Open
Abstract
Access to Antiretroviral Therapy (ART) is threatened by the increased rate of loss to follow-up (LTFU) among adolescents on ART care. We investigated the rate of LTFU from HIV care and associated predictors among adolescents living with HIV/AIDS in Tanzania. A retrospective cohort analysis of adolescents on ART from January 2014 to December 2016 was performed. Kaplan-Meier method was used to determine failure probabilities and the Cox proportion hazard regression model was used to determine predictors of loss to follow up. A total of 25,484 adolescents were on ART between 2014 and 2016, of whom 78.4% were female and 42% of adolescents were lost to follow-up. Predictors associated with LTFU included; adolescents aged 15–19 years (adjusted hazard ratio (aHR): 1.57; 95% Confidence Interval (CI); 1.47–1.69), having HIV/TB co-infection (aHR: 1.58; 95% CI, 1.32–1.89), attending care at dispensaries (aHR: 1.12; 95% CI, 1.07–1.18) or health center (aHR: 1.10; 95% CI, 1.04–1.15), and being malnourished (aHR: 2.27; 95% CI,1.56–3.23). Moreover, residing in the Lake Zone and having advanced HIV disease were associated with LTFU. These findings highlight the high rate of LTFU and the need for intervention targeting older adolescents with advanced diseases and strengthening primary public facilities to achieve the 2030 goal of ending HIV as a public health threat.
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A developmental analysis of dimensions of empathy during early adolescence: Behavioral empathy but not cognitive empathy is associated with lower psychopathology. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0001231. [PMID: 36962683 PMCID: PMC10021927 DOI: 10.1371/journal.pgph.0001231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 10/09/2022] [Indexed: 11/09/2022]
Abstract
Construct definitions of empathy have sought to distinguish between different dimensions of empathetic capacity that are significantly associated with psychological distress or wellbeing. Research has provided substantial evidence differentiating affective and cognitive empathy; however, more recent research has cited the importance of a third domain represented by empathetic behaviors and compassionate intent to comfort others. Examining developmental and maturational stage during the rapid transitional period of early adolescence is needed to model developmental trajectories, mechanisms of change and mental health outcomes. This study aims to assess relationships between pubertal developmental stage, dimensions of empathy, and depression, anxiety and externalizing behaviors among early adolescents. A cross-sectional survey among young adolescents ages 9-12 years was conducted in Dar es Salaam, Tanzania. The relationships between pubertal developmental stage, affective, cognitive, and behavioral empathy scores and internalizing and externalizing symptoms were evaluated using hierarchical regression modeling. Structural equation modeling was used to test a theoretical model of structural paths between these variables. A sample of 579 very young adolescents (270 boys and 309 girls) aged 9-12 years participated in the study. Pubertal development scale scores were associated with affective, cognitive, and behavioral empathy. Adolescents who had greater behavioral empathy scores reported lower internalizing and externalizing symptoms. Adolescents who had transitioned further through puberty and had higher cognitive empathy scores and reported higher internalizing symptoms. These findings support the importance of pubertal developmental stage in assessing risk and protective paths to mental health during adolescence. While empathetic capacity is widely perceived to be a positive trait, dimensional analysis of empathy among early adolescents indicates that behavioral skills and compassionate acts may be particularly protective and promote positive mental health outcomes.
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Acquired HIV drug resistance among children and adults receiving antiretroviral therapy in Tanzania: a national representative survey protocol. BMJ Open 2021; 11:e054021. [PMID: 34921085 PMCID: PMC8689191 DOI: 10.1136/bmjopen-2021-054021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Tanzania is making an enormous effort in scaling-up of antiretroviral therapy (ART). However, people living with HIV (PLHIV) continue to succumb to the challenge of drug resistance. Evidence on drug resistance for a national survey is unavailable in Tanzania. Therefore, we sought to assess viral suppression (vs) rates and magnitude of acquired drug resistance (ADR) among PLHIV. METHODS AND ANALYSIS A national survey will be conducted from 26 July to 29 October 2021 in 22 regions, recruiting 2160 participants. These will include adults on ART for 9-15 months and ≥48 months and children on ART for 9-15 months and ≥36 months. A standardised questionnaire will capture participants' demographic and clinical data. Plasma and dried blood spot will be prepared for viral load testing and drug resistance genotyping. Statistical analyses to determine the burden of ADR, characteristics and factors associated therewith will be done using STATA V.15. ETHICS AND DISSEMINATION Ethical approval has been obtained from the National Health Research Ethics Committee of Tanzania (NIMR/HQ/R.8a/Vol.IX/3432). Appropriate participant informed consent or parental consent and assent will be obtained. Dissemination will include a survey report, conference presentations, policy briefs and peer-reviewed publications.
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Preparing a financial incentive program to improve retention in HIV care and viral suppression for scale: using an implementation science framework to evaluate an mHealth system in Tanzania. Implement Sci Commun 2021; 2:109. [PMID: 34556176 PMCID: PMC8461932 DOI: 10.1186/s43058-021-00214-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 09/06/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Viral suppression is key to ending the HIV epidemic, yet only 58% of people living with HIV (PLHIV) in sub-Saharan Africa are suppressed. Cash transfers are an effective strategy to improve retention in care, but little is known about optimization of implementation; for example, designing effective programs that integrate into existing clinic workflows. We studied implementation of an mHealth system to deliver cash transfers to support retention. METHODS We conducted a mixed-methods study assessing implementation of an mHealth cash transfer study. This was part of a larger, hybrid implementation-effectiveness randomized controlled trial evaluating cash transfers conditional on visit attendance for viral suppression among Tanzanian PLHIV initiating ART. An mHealth system using fingerprint identification and mobile payments was used to automatically disburse mobile money to eligible PLHIV. We used Proctor's framework, assessing implementation of the mHealth system from the perspectives of PLHIV and clinicians. We analyzed mHealth system data and conducted surveys (n = 530) and in-depth interviews (n = 25) with PLHIV, clinic and pharmacy staff (n = 10), and structured clinic observations (n = 2293 visits). RESULTS One thousand six hundred fifty-one cash transfers were delivered to 346 PLHIV in the cash arms, 78% through mobile money. Among those in the cash arms, 81% registered their mobile money account with the mHealth system by study end, signaling high adoption. While acceptability for fingerprinting and mobile payments was high among PLHIV, interviews revealed mixed views: some had privacy concerns while others felt the system was secure and accurate, and provided some legitimacy to the clinical visits. Pharmacists praised system efficiency, but concerns about duplicative recordkeeping and added work arose. Clinic staff voiced excitement for the system's potential to bring the cash program to all patients and simplify workflows; yet concerns about multiple systems, staffing, and intermittent connectivity tempered enthusiasm, highlighting structural issues beyond program scope. Structured observations revealed a steep learning curve; repeat fingerprint scans and manual entry declined as the system improved. CONCLUSIONS Biometric identification and mobile payments were acceptable to most patients and staff. Fingerprinting encountered some feasibility limitations in the first months of testing; however, mobile payments were highly successful. Biometric identification and mobile payments may provide a scalable mechanism to improve patient tracking and efficiently implement financial incentives in low-resource settings. TRIAL REGISTRATION Name of the registry: clinicaltrials.gov Trial registration number: NCT03351556 Date of registration: 11/24/2017 Checklists: StaRI (included with submission). Note CONSORT for cluster-randomized trials was used for the main trial but is not directly applicable to this manuscript.
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Designing drug shops for young women in Tanzania: applying human-centred design to facilitate access to HIV self-testing and contraception. Health Policy Plan 2021; 36:1562-1573. [PMID: 34313728 PMCID: PMC8597958 DOI: 10.1093/heapol/czab084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/31/2021] [Accepted: 07/13/2021] [Indexed: 12/02/2022] Open
Abstract
Adolescent and young adult women in sub-Saharan Africa experience barriers to sexual and reproductive health (SRH) services that elevate their risk of human immunodeficiency virus (HIV) acquisition and unintended pregnancy. Community drug shops may be effective distribution points to connect young women with SRH products. Thus, we used human-centred design (HCD) to create drug shops where young women could access HIV self-testing and contraception in Shinyanga, Tanzania. Enhancing the HCD process with behavioural science, we collected diverse data (i.e. 18 in-depth interviews, 9 ‘shadowing’ interviews, 6 shop observations, 6 focus groups) to understand the latent needs and motivations of young women and drug shopkeepers, brainstormed creative solutions and iteratively refined and tested solutions for acceptability, feasibility and cultural fit. We found a widespread moral imperative to control young women’s behaviour via misinformation about SRH, community gossip and financial control. Young women often engaged in mundane shopping at the behest of others. At drug shops, few SRH products were deemed appropriate for unmarried women, and many reactively sought SRH products only after engaging in higher risk behaviours. In response to these insights, we designed the ‘Malkia Klabu’ (‘Queen Club’) loyalty programme through which young women could earn mystery prizes by shopping at drug shops and discreetly request free SRH products, including HIV self-test kits, by pointing at symbols on loyalty cards. Our HCD approach increases the likelihood that the intervention will address the specific needs and preferences of both drug shopkeepers and young women. We will evaluate its effectiveness in a randomized trial.
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Sales and pricing decisions for HIV self-test kits among local drug shops in Tanzania: a prospective cohort study. BMC Health Serv Res 2021; 21:434. [PMID: 33957903 PMCID: PMC8101213 DOI: 10.1186/s12913-021-06432-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 04/22/2021] [Indexed: 11/14/2022] Open
Abstract
Background Public health initiatives must look for ways to cost-effectively scale critical interventions to achieve high coverage. Private sector distribution channels, can potentially distribute preventive healthcare products to hard-to-reach populations, decongest public healthcare systems, and increase the sustainability of programs by getting customers to share costs. However, little is known about how sellers set prices for new products. By introducing a new product, HIV self-test kits, to local drug shops, we observed whether shops experimented with pricing, charged different buyers different prices, and whether prices converged within the local market over our study period. Methods From August to December 2019, we provided free HIV self-test kits, a new product, to 26 drug shops in Shinyanga, Tanzania to sell to the local community. We measured sales volume, price, customer age and sex using shop records. Using a multiple linear regression model, we conducted F-tests to determine whether shop, age, sex, and time (week) respectively were associated with price. We measured willingness-to-pay to restock test kits at the end of the study. Results 514 test kits were sold over 18 weeks; 69% of buyers were male, 40% were aged 25–34 and 32% aged 35–44. Purchase prices ranged from 1000 to 6000 Tsh (median 3000 Tsh; ~$1.30 USD). Within shops, prices were 11.3% higher for 25–34 and 12.7% higher for 45+ year olds relative to 15–19-year olds (p = 0.029) and 13.5% lower for men (p = 0.023) on average. Although prices varied between shops, prices varied little within shops over time, and did not converge over the study period or cluster geospatially. Mean maximum willingness-to-pay to restock was 2000 Tsh per kit. Conclusions Shopkeepers charged buyers different prices depending on buyers’ age and sex. There was limited variation in prices within shops over time and low demand among shopkeepers to restock at the end of the study. Given the subsidized global wholesale price ($2 USD or ~ 4600 Tsh), further demand creation and/or cost-reduction is required before HIV self-test kits can become commercially viable in drug shops in this setting. Careful consideration is needed to align the motivations of retailers with public health priorities while meeting their private for-profit needs. Supplementary Information The online version contains supplementary material available at 10.1186/s12913-021-06432-1.
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Optimizing the efficiency and implementation of cash transfers to improve adherence to antiretroviral therapy: study protocol for a cluster randomized controlled trial. Trials 2020; 21:963. [PMID: 33228757 PMCID: PMC7684892 DOI: 10.1186/s13063-020-04899-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 11/12/2020] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Antiretroviral therapy (ART) for HIV, taken daily, is an effective strategy to clinically suppress the virus, providing the dual benefit of improved survival and vastly decreasing the risk of transmission. However, this highly effective intervention has not yet reached all who could benefit. Cash transfers are increasingly recognized as an effective strategy to motivate behavior change and improve HIV care and treatment outcomes, including engagement in HIV care and adherence to ART. Despite a growing evidence base and strong theoretical foundation for the cash transfer approach, key questions remain. To address these questions and begin to bridge the "know-do gap" with respect to cash transfers, our team is employing an implementation science approach to iterative development of an incentive-based intervention to promote ART uptake and adherence among people living with HIV (PLHIV) in the Lake Zone region, Tanzania. METHODS We will conduct a type I hybrid implementation-effectiveness trial to test the effectiveness of a cash transfer intervention on the outcome of HIV viral suppression, and concurrently examine the potential for real-world implementation with a mobile health technology (mHealth) system. Specifically, our team will expand the intervention to 32 clinics and enroll 1984 PLHIV to (a) evaluate its effectiveness by conducting a cluster randomized controlled trial with clinics as the unit of randomization and 12-month viral suppression as the primary outcome and (b) evaluate the implementation challenges and successes at multiple levels (patient, provider, clinic). DISCUSSION This trial will provide evidence not only about the real-world effectiveness of cash transfers for retention in HIV care and viral suppression, but also on the implementation challenges and successes that will facilitate or hinder wider scale-up within Tanzania and beyond. TRIAL REGISTRATION ClinicalTrials.gov NCT04201353 . Registered on December 17, 2019.
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Cost variations in prevention of mother-to-child HIV transmission services integrated within maternal and child health services in rural Tanzania. Glob Public Health 2020; 16:305-318. [PMID: 32726197 DOI: 10.1080/17441692.2020.1798486] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We estimated the costs of Option B+ for HIV-infected pregnant women in 12 facilities in Morogoro Region, Tanzania, from a provider perspective. Costs of prevention of mother-to-child (PMTCT) HIV services were measured over 12 months to September 2017 to estimate the average costs per HIV testing episode, per HIV-positive case diagnosed, per patient-year on antiretroviral therapy (ART), and per neonatal HIV care. A one-way sensitivity analysis was undertaken to understand how staffing levels and other core resource inputs affected costs. The total number of HIV testing episodes was 25,593 with 279 HIV cases identified yielding a 1.1% positivity rate. The average cost per testing episode was US$5.49 (range US$2.13 to US$13.93), and the average cost per HIV case detected was US$503.29 (range US$230.61 to US$3330.38). The number of pregnant women initiated on ART was 278. The mean cost per patient-year on ART was US$159.89 (range US$100.91 to US$812.23). The average cost of neonatal HIV care was US$90.09 (range US$41.53 to US$180.26). PMTCT service costs varied widely across facilities due to variations in resource use, number of women testing, and HIV prevalence. The study provides further evidence against generalising cost estimates, and that budgeting and planning requires context specific cost information.
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Unpacking Loss to Follow-Up Among HIV-Infected Women Initiated on Option B+ In Northern Tanzania: A Retrospective Chart Review. East Afr Health Res J 2019. [DOI: 10.24248/eahrj.v3i1.593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Unpacking Loss to Follow-Up Among HIV-Infected Women Initiated on Option B+ In Northern Tanzania: A Retrospective Chart Review. East Afr Health Res J 2019; 3:6-15. [PMID: 34308190 PMCID: PMC8279164 DOI: 10.24248/eahrj-d-18-00025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 05/24/2019] [Indexed: 11/20/2022] Open
Abstract
Background: In 2014, Tanzania adopted the Option B+ policy for the prevention of mother-to-child transmission of HIV (PMTCT), which stipulates lifelong antiretroviral therapy (ART) for HIV-infected pregnant, postpartum and breastfeeding women, irrespective of CD4 count or WHO clinical staging. Loss to follow-up (LTFU) during pregnancy and the postpartum period may undermine the effectiveness of Option B+. Factors associated with no follow-up (NFU) care, may differ from those associated with LTFU at later time points. This study aimed to identify factors associated with NFU and LTFU among women who initiate ART under Option B+ in Moshi, Tanzania. Methods: We conducted a retrospective chart review of patients initiating ART on Option B+ between February 2014 and December 2015 in Moshi Municipality, Tanzania. Multivariable log-binomial regression was used to analyse factors associated with NFU. Kaplan-Meier survival functions were used to estimate time to LTFU. Multivariable Cox proportion hazards regression models were used to evaluate variables associated with time to LTFU. Results: Among 468 women initiating ART under the option B+ programme, 109 (23.3%) had NFU after the initial appointment. Factors associated with increased risk of NFU were: age < 25 years (adjusted hazard ratio [aRR] 1.7; 95% CI, 1.2 to 2.3), initiating ART at a hospital compared to a lower level health facilities (aRR 2.9; 95% CI, 2.1 to 3.9), and having no treatment supporter (aRR 1.5; 95% CI, 1.1 to 2.1). LTFU was higher in women aged < 25 years (aHR 1.4; 95% CI, 1.1 to 1.9), and in women with no treatment supporter (aHR 1.8; 95% CI, 1.4 to 2.3). In women who returned to the clinic after ART initiation, no factor was significantly associated with LTFU. Conclusion: The factors associated with NFU (being young, not having a treatment supporter, and being diagnosed at hospitals) reflect a vulnerable and potentially highly mobile population. Additional interventions are needed to support and retain this group at ART initiation on Option B+.
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It helps me live, sends my children to school, and feeds me: a qualitative study of how food and cash incentives may improve adherence to treatment and care among adults living with HIV in Tanzania. AIDS Care 2017; 29:876-884. [PMID: 28397527 DOI: 10.1080/09540121.2017.1287340] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Financial and in-kind incentives have been shown to improve outcomes along the HIV care cascade, however the potential mechanismsthrough which they work remain unclear. To identify the pathways through which incentives improve retention in care and adherence to antiretroviral therapy (ART), we conducted a qualitative study with participants in a trial evaluating conditional food and cash incentives for HIV-positive food insecure adults in Shinyanga, Tanzania. We found that the incentives acted through three pathways to potentially increase retention in care and adherence to ART: (1) addressing competing needs and offsetting opportunity costs associated with clinic attendance, (2) alleviating stress associated with attending clinic and meeting basic needs, and (3) by potentially increasing motivation. Participants did not report any harmful events associated with the incentives, but reported myriad beneficial effects on household welfare. Understanding how incentives are used and how they impact outcomes can improve the design of future interventions.
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Challenges with routine data sources for PMTCT programme monitoring in East Africa: insights from Tanzania. Glob Health Action 2015; 8:29987. [PMID: 26715204 PMCID: PMC4695617 DOI: 10.3402/gha.v8.29987] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 12/01/2015] [Accepted: 12/03/2015] [Indexed: 11/25/2022] Open
Abstract
Routinely collected clinic data have the potential to provide much needed information on the uptake of services to prevent mother-to-child transmission (PMTCT) of HIV, and to measure HIV prevalence in pregnant women. This article describes the methodological challenges associated with using such data, based on the experiences of researchers and programme implementers in Tanzania and drawing from other examples from East Africa. PMTCT data are routinely collected in maternal and child health (MCH) clinics in East Africa using paper-based registers corresponding to distinct services within the PMTCT service continuum. This format has inherent limitations with respect to maintaining and accurately recording unique identifiers that can link patients across the different clinics (antenatal, delivery, child), and also poses challenges when compiling aggregate data. Recent improvements to recording systems include assigning unique identifiers to HIV-positive pregnant women in MCH clinics, although this should ideally be extended to all pregnant women, and recording mother and infant identifiers alongside each other in registers. The use of ‘health passports’, as in Malawi, which maintains the same antenatal clinic identifier over time, also holds promise. Routine data hold tremendous potential for clinic-level patient management, surveillance, and evaluating PMTCT/MCH programmes. Linking clinic data to community research datasets can also provide population-level estimates of coverage with PMTCT services, currently a problematic but vital statistic for monitoring programme performance and negotiating donor funding. Enhancements to indexing and recording of routine PMTCT/MCH data are needed if we are to capitalise on this rich data source.
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Field Resistance to the Ug99 Race Group of the Stem Rust Pathogen in Spring Wheat Landraces. PLANT DISEASE 2013; 97:882-890. [PMID: 30722524 DOI: 10.1094/pdis-02-12-0200-re] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Wheat landraces provide a source of genetic variability for breeding. The emergence and spread of highly virulent races of the stem rust pathogen (Ug99 race group of Puccinia graminis f. sp. tritici) threaten wheat production globally. Spring wheat landraces were screened for resistance in eight field seasons at the Kenya Agricultural Research Institute, Njoro, where the Ug99 race group has become endemic. Accessions showing resistance in one season were retested and screened with molecular markers associated with resistance genes Sr2, Sr24, Sr36, and Lr34/Yr18; two height-reducing genes; and a photoperiod insensitivity allele. Of 2,509 accessions tested, 278 were categorized as resistant based on results from at least two seasons. Of these resistant accessions, 32 were positive for one or more markers for Sr2, Sr36, Rht-B1b, or Rht-D1b, indicating that they do not fit the definition of "landrace" because these genes were likely introduced via modern breeding practices. Thus, 246 resistant "landrace" accessions were identified. Of countries with more than five tested accessions, Afghanistan, Iran, Portugal, Ethiopia, Uzbekistan, Greece, Tajikistan, Bosnia and Herzegovina, and Serbia had at least 10% of tested accessions that were resistant to the Ug99 race group. Future research will characterize the resistance to determine its novelty and incorporate novel genes into improved lines.
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Abstract
Since the mid-1980s, rice cultivation has expanded rapidly in Burundi to reach approximately 50,000 ha in 2011. In 2007, leaf mottling, reduced tillering, and stunting symptoms were observed on rice at Gatumba near Bujumbura, causing small patches in less than 10% of the fields. Rice yellow mottle virus (RYMV, genus Sobemovirus), which has seriously threatened rice cultivation in Africa (1) and was recently described in the neighboring Rwanda (3), was suspected to be involved because of similar symptoms. To identify the pathogen that caused the disease in Burundi, a survey was performed in the major rice-producing regions of Burundi and Rwanda. Six locations in Burundi and four in Rwanda were investigated in April and October 2011. Disease incidence in the fields was estimated to be 15 ± 5%. Symptomatic leaves of 24 cultivated rice plants were collected and tested by double antibody sandwich-ELISA with polyclonal antibodies raised against the RYMV isolate Mg1 (2). All tested samples reacted positively. Four isolates were inoculated on susceptible Oryza sativa cultivar IR64 (2). The typical symptoms of RYMV were reproduced 7 days after inoculation, whereas the noninoculated controls remained healthy. Total RNA was extracted by the RNeasy Plant Mini kit (QIAGEN, Hilden, Germany) from 12 samples. The RYMV coat protein gene was amplified by RT-PCR with primers 5'CGCTCAACATCCTTTTCAGGGTAG3' and 5'CAAAGATGGCCAGGAA3' (3). The sequences were deposited in GenBank (Accession Nos. HE654712 to HE654723). To characterize the isolates, the sequences of the tested samples were compared in a phylogenic tree including a set of 45 sequences of isolates from Rwanda, Uganda, western Kenya, and northern Tanzania (2,3). Six isolates from western Burundi, namely Bu1, Bu2, Bu4, Bu7, Bu10, and Bu13 (Accession Nos. HE654712 to HE654716 and HE654718), and the isolate Rw208 (HE654720) from southwestern Rwanda, belonged to strain S4-lm previously reported near Lakes Malawi and Tanganyika. They fell within the group gathering isolates from the western Bugarama plain of Rwanda (3). The isolates Bu16 (HE654719) and Bu17 (HE654717) from Mishiha in eastern Burundi belonged to strain S4-lv previously reported around Lake Victoria. However, they did not cluster with isolates from the eastern and southern provinces of Rwanda. They were genetically more closely related to isolates of strain S4-lv from northern Tanzania. Overall, the phylogeography of RYMV in Burundi and Rwanda region was similar. In the western plain of the two countries, the isolates belonged to the S4-lm lineage, whereas at the east of the two countries at midland altitude, they belonged to the S4-lv lineage. The presence of RYMV in Burundi should be considered in the future integrative pest management strategies for rice cultivation in the country. References: (1) D. Fargette et al. Annu. Rev. Phytopathol. 44:235, 2006. (2) Z. L. Kanyeka et al. Afr. Crop Sci. J. 15:201, 2007. (3) I. Ndikumana et al. New Dis. Rep. 23:18, 2011.
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Sources of Resistance to Stem Rust Race Ug99 in Spring Wheat Germplasm. PLANT DISEASE 2011; 95:762-766. [PMID: 30731910 DOI: 10.1094/pdis-12-10-0940] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Wheat stem rust (Puccinia graminis f. sp. tritici) race TTKSK (Ug99), with virulence to the majority of the world's wheat (Triticum aestivum) cultivars, has spread from Uganda throughout eastern Africa, Yemen, and Iran. The identification and spread of variants of race TTKSK with virulence to additional stem rust resistance genes has reminded breeders and pathologists of the danger of deploying major resistance genes alone. In order to protect wheat from this rapidly spreading and adapting pathogen, multiple resistance genes are needed, preferably from improved germplasm. Preliminary screening of over 700 spring wheat breeding lines and cultivars developed at least 20 years ago identified 88 accessions with field resistance to Ug99. We included these resistant accessions in the stem rust screening nursery in Njoro, Kenya for two additional seasons. The accessions were also screened with a bulk of North American isolates of P. graminis f. sp. tritici in the field in St. Paul, MN. In order to further characterize the resistance in these accessions, we obtained seedling phenotypes for 10 races of P. graminis f. sp. tritici, including two races from the race TTKSK complex. This phenotyping led to the identification of accessions with either adult-plant or all-stage resistance to race TTKSK, and often North American races of P. graminis f. sp. tritici as well. These Ug99 resistant accessions can be obtained by breeders and introgressed into current breeding germplasm.
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Detection of Virulence to Resistance Gene Sr36 Within the TTKS Race Lineage of Puccinia graminis f. sp. tritici. PLANT DISEASE 2009; 93:367-370. [PMID: 30764215 DOI: 10.1094/pdis-93-4-0367] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The stem rust resistance gene Sr36 confers a near-immune resistance reaction to many races of Puccinia graminis f. sp. tritici and is highly effective against race TTKSK (syn. Ug99), which possesses unusually broad virulence combinations. Because this gene is widely used in United States soft winter wheat germplasm and cultivars, it has been considered to be an important source of resistance to TTKSK. In 2007, moderately susceptible infection responses were observed on wheat lines and cultivars carrying Sr36 in a field screening nursery for stem rust at Njoro, Kenya. We derived 18 single-pustule isolates from stem rust samples collected from the 2007 Njoro nursery. The isolates were evaluated for virulence on 20 North American stem rust differential lines and on wheat lines and cultivars carrying Sr36, Sr31+Sr36, and Sr24+Sr31. Of the 18 isolates, 10 produced infection types 3+ to 4 on line W2691SrTt-1 (monogenic for Sr36) and other lines that carry Sr36 and belonged to a new virulence phenotype that was not detected in previous years. These isolates were identified as race TTTSK. The remaining eight isolates were identified as races TTKSK (five isolates) and TTKST (three isolates), with avirulence and virulence, respectively, to Sr24. Thirteen simple sequence repeat (SSR) markers were used to examine the genetic relationships among the three races in the TTKS lineage. All isolates in the lineage shared an identical SSR genotype and were clearly different from North American races. In all, 16 wheat cultivars and 60 elite breeding lines, postulated to possess Sr36, were susceptible to race TTTSK. The occurrence of race TTTSK with combined virulence on Sr31 and Sr36 has further broadened the virulence spectrum of the TTKS lineage and rendered an important source of resistance ineffective.
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Characterization of Seedling Infection Types and Adult Plant Infection Responses of Monogenic Sr Gene Lines to Race TTKS of Puccinia graminis f. sp. tritici. PLANT DISEASE 2007; 91:1096-1099. [PMID: 30780647 DOI: 10.1094/pdis-91-9-1096] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Stem rust, caused by Puccinia graminis f. sp. tritici, historically was one of the most destructive diseases of wheat and barley. The disease has been under effective control worldwide through the widespread use of host resistance. A number of stem rust resistance genes in wheat have been characterized for their reactions to specific races of P. graminis f. sp. tritici. Adult plant responses to race TTKS (also known as Ug99) of monogenic lines for Sr genes, a direct measurement of the effectiveness for a given gene, have not been investigated to any extent. This report summarizes adult plant infection responses and seedling infection types for monogenic lines of designated Sr genes challenged with race TTKS. High infection types at the seedling stage and susceptible infection responses in adult plants were observed on monogenic lines carrying Sr5, 6, 7a, 7b, 8a, 8b, 9a, 9b, 9d, 9g, 10, 11, 12, 15, 16, 17, 18, 19, 20, 23, 30, 31, 34, 38, and Wld-1. Monogenic lines of resistance genes Sr13, 22, 24, 25, 26, 27, 28, 32, 33, 35, 36, 37, 39, 40, 44, Tmp, and Tt-3 were effective against TTKS both at the seedling and adult plant stages. The low infection types to race TTKS observed for these resistance genes corresponded to the expected low infections of these genes to other incompatible races of P. graminis f. sp. tritici. The level of resistance conferred by these genes at the adult plant stage varied between highly resistant to moderately susceptible. The results from this study were inconclusive for determining the effectiveness of resistance genes Sr9e, 14, 21, and 29 against race TTKS. The understanding of the effectiveness of individual Sr genes against race TTKS will facilitate the utilization of these genes in breeding for stem rust resistance in wheat.
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