Publications by authors named "Katherine K Thomas"
Lipoarabinomannan (LAM) is a promising target biomarker for diagnosing subclinical and clinical tuberculosis (TB). Urine LAM (uLAM) testing using rapid diagnostic tests (RDTs) has been approved for people living with HIV (PLWH), however there is limited data regarding uLAM levels in HIV-negative (HIV-ve) adults with clinical TB. We conducted a clinical study of adults presenting with clinical TB-related symptoms at the National Lung Hospital in Hanoi, Vietnam.
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- Development of a non-sputum test for tuberculosis (TB) using lipoarabinomannan (LAM) biomarker concentrations in urine and blood samples was studied to improve diagnostic accuracy, particularly for individuals with and without HIV.
- A diagnostic study in South Africa evaluated LAM levels in urine, plasma, and serum among adults with TB symptoms, finding urine LAM sensitivity of 62% and specificity of 99% using the S4-20 assay; higher sensitivity was observed in HIV-negative participants.
- The findings suggest that while non-sputum specimens can detect LAM for TB diagnosis, improving analyte concentration or signal amplification may be necessary to meet
Article Synopsis
- - The study aimed to assess the effectiveness of a new point-of-care urine tenofovir (POC TFV) test in improving the accuracy of self-reported adherence to preexposure prophylaxis (PrEP) among sexually active HIV-negative women in Uganda.
- - Over 24 months, participants who took the test reported higher rates of low PrEP adherence and condomless sex during visits with the test compared to those without it, indicating that the test may encourage more honest self-reporting.
- - The accuracy of self-reported PrEP adherence significantly increased when the POC TFV test was utilized, suggesting that the test could foster better communication between patients and healthcare providers.
Bacterial vaginosis (BV) is a dysbiosis of the vaginal microbiome that is prevalent in reproductive-age women worldwide. Adverse outcomes associated with BV include an increased risk of sexually acquired Human Immunodeficiency Virus (HIV), yet the immunological mechanisms underlying this association are not well understood. To investigate BV driven changes to cervicovaginal tract (CVT) and circulating T cell phenotypes, participants with or without BV provided vaginal tract (VT) and ectocervical (CX) tissue biopsies and peripheral blood mononuclear cells (PBMC).
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- Routine HIV viral load testing is crucial for assessing treatment outcomes, but traditional methods face challenges like high costs and slow result delivery.
- The GeneXpert HIV-1 quantification assay is a potential solution, offering faster and cheaper point-of-care testing, although its real-world effectiveness is still under review.
- Analysis of 900 samples from studies in Kenya shows that GeneXpert performs well in terms of specificity and agreement with standard testing but has lower sensitivity, indicating that while it could be a reliable monitoring tool, further investigation is needed to ensure accurate results.
Background: Contraceptive use has complex effects on sexual behaviour and mood, including those related to reduced concerns about unintended pregnancy, direct hormonal effects and effects on endogenous sex hormones. We set out to obtain robust evidence on the relative effects of three contraceptive methods on sex behaviours, which is important for guiding contraceptive choice and future contraceptive developments.
Methods: This is a secondary analysis of data from the Evidence for Contraceptive Options and HIV Outcomes (ECHO) randomized trial in which 7,829 HIV-uninfected women from 12 sites in Eswatini, Kenya, South Africa and Zambia seeking contraception were randomly assigned to intramuscular depot-medroxyprogesterone acetate (DMPA-IM), the copper intrauterine device (Cu-IUD) or the levonorgestrel (LNG) implant.
Article Synopsis
- The STREAM study assessed risk factors for HIV viraemia and retention in care 18 months after starting antiretroviral therapy in 390 participants in Durban, South Africa.
- Approximately 11.5% of participants lost care and 11.8% had viraemia 18 months after treatment, with those having CD4 counts <200 or previous viraemia at higher risk of ongoing viraemia and care issues.
- Early indicators like initial viraemia are crucial for targeting interventions to assist individuals likely to face ongoing health challenges in managing their HIV.
Article Synopsis
- Integrating PrEP with ART programs helps prevent HIV transmission in couples where one partner is HIV-positive before achieving viral suppression.
- The study developed a 24-item scale to measure behavioral modeling among these couples, focusing on how partners influence each other's medication habits.
- A five-factor model was identified, showing that behaviors like attention to partner actions and relationship quality impact medication adherence, highlighting the importance of partner influence in HIV prevention strategies.
Article Synopsis
- Adolescent girls and young women (AGYW) in East and southern Africa face high rates of HIV infection, and integrating pre-exposure prophylaxis (PrEP) in existing healthcare services, like post-abortion care, is essential to address this issue.* ! -
- A study conducted in Kenya from March 2021 to November 2022 found that 57.4% of AGYW were offered PrEP, with 14.1% actually starting it; factors like consistent PrEP supply and staff training played significant roles in increasing both offers and uptake of PrEP.* ! -
- Successful integration of HIV prevention into reproductive health services will depend on strengthening healthcare systems and ensuring consistent availability of necessary resources like Pr
Article Synopsis
- Intimate partner violence (IPV) has been linked to lower adherence to antiretroviral treatment (ART), particularly in heterosexual serodifferent couples in Uganda, where the partner living with HIV is often female.
- A study of 149 couples showed that those experiencing IPV had significantly lower rates of ART adherence compared to those not exposed to IPV, while PrEP adherence was not notably affected.
- Additionally, individuals in relationships with moderate powerlessness were more likely to adhere to PrEP, suggesting that relationship dynamics can play a role in medication adherence for those in HIV serodifferent partnerships.
Introduction: Lack of viral suppression (VS) among pregnant and breastfeeding women living with HIV poses challenges for maternal and infant health, and viral load (VL) monitoring via centralized laboratory systems faces many barriers. We aimed to determine the impact of point-of-care (POC) VL and targeted drug resistance mutation (DRM) testing in improving VS among pregnant and postpartum women on antiretroviral therapy.
Methods: We conducted a pre/post-intervention prospective cohort study among 820 pregnant women accessing HIV care at five public-sector facilities in western Kenya from 2019 to 2022.
Article Synopsis
- * The study included randomizing children into control and intervention groups, where the latter received more frequent viral load testing and drug resistance testing in response to treatment failures, revealing high rates of major drug-resistant mutations.
- * Key factors associated with increased drug resistance included a history of virologic failure in the past two years and being on ART for less than two years, suggesting these are critical indicators for prioritizing drug resistance testing in affected children.
Article Synopsis
- Many young women globally experience the dual challenges of HIV and unintended pregnancies, highlighting the need for multipurpose prevention technologies.
- A study involving 312 healthy women aged 18-34 randomized participants to use either a tenofovir/levonorgestrel (TFV/LNG), TFV-only, or placebo intravaginal ring to assess safety and effectiveness.
- Results showed that both TFV IVR groups demonstrated significant increases in HIV inhibition in cervicovaginal fluid, with no serious adverse effects linked to the products, indicating their potential as safe prevention methods.
Background: An important cervical cancer prevention strategy in low- and middle-income countries (LMICs) has been single-visit screen-and-treat (SV-SAT) approach, using visual inspection with acetic acid (VIA) and ablative treatment with cryotherapy to manage precancerous lesions. While SV-SAT with VIA and cryotherapy have established efficacy, its population level coverage and impact on reducing cervical cancer burden remains low. In Kenya, the estimated cervical cancer screening uptake among women aged 30-49 is 16% and up to 70% of screen-positive women do not receive treatment.
View Article and Find Full Text PDFImportance: Daily oral HIV preexposure prophylaxis (PrEP) delivery requires quarterly clinic visits for HIV testing and drug refilling that are costly to health systems and clients.
Objective: To evaluate whether 6-month PrEP dispensing supported with interim HIV self-testing (HIVST) results in noninferior PrEP continuation outcomes at 12 months compared with standard quarterly clinic visits.
Design, Setting, And Participants: This randomized noninferiority trial was conducted from May 2018 to May 2021 with 12 months of follow-up among PrEP clients aged 18 years or older who were returning for their first refill at a research clinic in Kiambu County, Kenya.
Article Synopsis
- - The study assessed IUD insertion outcomes by newly trained clinicians at 12 sites in Africa, noting a 5.46% failure rate and a 0.27% perforation rate, particularly higher among breastfeeding women postpartum.
- - Results showed that of 2582 women, 493 experienced expulsions, with lower risk in women over 24 and potential higher risk in nulliparous women; however, breastfeeding did not significantly impact expulsion rates.
- - The findings suggest that effective training and ongoing support for new providers can lead to successful IUD insertions in resource-limited settings, aligning with existing literature on safety and efficacy.
Article Synopsis
- The study examined the impact of South Africa’s CCMDD program on the clinical outcomes of HIV patients, focusing on viral load suppression and patient retention in care compared to traditional clinic-based care.
- Out of 390 patients assessed for the program, 116 participated, demonstrating high levels of adherence and timely ART distribution at 93% of visits.
- Results showed no significant differences in viral load suppression and retention between those who participated in the CCMDD program and those who did not, suggesting the community-based model is effective for maintaining HIV care outcomes.
Importance: Variants of SARS-CoV-2 have sequence variations in the viral genome that may alter the accuracy of rapid diagnostic tests.
Objective: To assess the analytical and clinical accuracy of 2 rapid diagnostic tests for detecting SARS-CoV-2 during 3 phases of variants.
Design, Setting, And Participants: This diagnostic study included participants aged 18 years or older who reported onset of COVID-19-like symptoms within the prior 5 days and were tested at multiple COVID-19 testing locations in King County, Washington, from February 17, 2021, to January 11, 2022, during 3 distinct phases of SARS-CoV-2 infection (pre-Delta, Delta, and Omicron).
Background: Global scale-up of HIV pre-exposure prophylaxis (PrEP) includes services to HIV-negative people in partnerships with people living with HIV (serodifferent couples). Data are needed on HIV outcomes, including uptake and adherence to PrEP and antiretroviral treatment (ART), to describe the impact of integrating PrEP into an existing HIV program.
Methods: Using a stepped-wedge cluster randomized trial design, we launched PrEP delivery for HIV-negative members of serodifferent couples in Uganda by integrating PrEP into existing ART programs for people living with HIV.
Article Synopsis
- The Opt4Kids study in Kenya aimed to improve viral suppression in HIV-positive children (aged 1-14) on antiretroviral therapy by testing point-of-care viral load and drug resistance mutation.* -
- The study enrolled 704 children and randomly assigned them to either the intervention group (which received additional testing every 3 months) or standard care, with virological suppression measured 12 months later.* -
- Results showed that at 12 months, virological suppression rates were similar between the intervention group (90%) and control group (92%), indicating no significant benefit of the additional testing in this context.*
Background: Oral pre-exposure prophylaxis (PrEP) for HIV prevention is highly effective and is being implemented at scale at health clinics throughout sub-Saharan Africa. However, barriers to clinic-based PrEP delivery remain. We aimed to establish the efficiency of semiannual PrEP clinic visits supplemented with interim home-based HIV self-testing (HIVST) versus standard of care for HIV testing, drug refilling, and adherence among PrEP users.
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- South Africa has the highest HIV burden globally, and understanding factors contributing to HIV acquisition is essential for improving national prevention strategies and future trials, as investigated in the ECHO study.
- The study followed 5,768 HIV-negative women aged 16-35 who sought contraceptive services between 2015 and 2018, with a total of 345 new HIV infections observed during the study.
- Key risk factors for incident HIV included being 24 years or younger, having a history of sexually transmitted infections, a BMI of 30 or less, and having new or multiple sexual partners prior to enrollment, highlighting the need for better integration of STI management with contraceptive services.
Understanding Pre-Exposure Prophylaxis Adherence in Young Women in Kenya.
J Acquir Immune Defic Syndr
March 2022
Article Synopsis
- The study aimed to analyze long-term PrEP use and related behaviors among young Kenyan women aged 18 to 24 at high risk for HIV in Kisumu and Thika.
- Over two years, researchers tracked 348 women, finding that PrEP adherence significantly dropped from 100% to 54% and electronically monitored adherence decreased from 65% to 15%.
- While some factors like clinic access influenced adherence, the overall low HIV incidence (0.7 per 100 person-years) suggests that participants may have utilized various protective strategies beyond PrEP.
Article Synopsis
- The study investigates how male sex influences the likelihood of testing positive for SARS-CoV-2, experiencing severe COVID-19, and mortality rates using data from a cohort at the University of Washington Medicine from March to September 2020.
- In the cohort of 67,652 individuals, males were found to be 14% more likely to test positive, had an 80% higher risk of severe COVID-19, and a 58% higher risk of death compared to females after considering age and race/ethnicity.
- The research suggests that while inflammation may play a role in the increased risk for severe COVID-19 in males, the effects through socioeconomic status and comorbidities were not significant.
Article Synopsis
- * The ECHO Trial studied young women (ages 16-35) from four African nations to understand factors affecting their initiation of ART after seroconversion.
- * Of 304 women monitored, only 61.2% started ART within 90 days, with common reasons for delay being a lack of readiness and the stress of a new diagnosis, despite receiving thorough counseling.