Isolde Birdthistle

Dr. Isolde Birdthistle

Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 January 2013 in Journal of the International AIDS Society
Verified
Journal Article
Open access
PDF file
AGAnnabelle Gourlay
Annabelle Gourlay
IBIsolde Birdthistle
Isolde Birdthistle
GMGitau Mburu
Gitau Mburu
KIKate Iorpenda
Kate Iorpenda
AWAlison Wringe
Alison Wringe
Objectives: To investigate and synthesize reasons for low access, initiation and adherence to antiretroviral drugs by mothers and exposed babies for prevention of mother‐to‐child transmission (PMTCT) of HIV in sub‐Saharan Africa.Methods: A systematic literature review was conducted. Four databases were searched (Medline, Embase, Global Health and Web of Science) for studies conducted in sub‐Saharan Africa from January 2000 to September 2012. Quantitative and qualitative studies were included that met pre‐defined criteria. Antiretroviral (ARV) prophylaxis (maternal/infant) and combination antiretroviral therapy (ART) usage/registration at HIV care and treatment during pregnancy were included as outcomes.Results: Of 574 references identified, 40 met the inclusion criteria. Four references were added after searching reference lists of included articles. Twenty studies were quantitative, 16 were qualitative and eight were mixed methods. Forty‐one studies were conducted in Southern and East Africa, two in West Africa, none in Central Africa and one was multi‐regional. The majority (n=25) were conducted before combination ART for PMTCT was emphasized in 2006. At the individual‐level, poor knowledge of HIV/ART/vertical transmission, lower maternal educational level and psychological issues following HIV diagnosis were the key barriers identified. Stigma and fear of status disclosure to partners, family or community members (community‐level factors) were the most frequently cited barriers overall and across time. The extent of partner/community support was another major factor impeding or facilitating the uptake of PMTCT ARVs, while cultural traditions including preferences for traditional healers and birth attendants were also common. Key health‐systems issues included poor staff‐client interactions, staff shortages, service accessibility and non‐facility deliveries.Conclusions: Long‐standing health‐systems issues (such as staffing and service accessibility) and community‐level factors (particularly stigma, fear of disclosure and lack of partner support) have not changed over time and continue to plague PMTCT programmes more than 10 years after their introduction. The potential of PMTCT programmes to virtually eliminate vertical transmission of HIV will remain elusive unless these barriers are tackled. The prominence of community‐level factors in this review points to the importance of community‐driven approaches to improve uptake of PMTCT interventions, although packages of solutions addressing barriers at different levels will be important.

30 January 2008 in AIDS
Verified
Journal Article
Closed access
JHJames R Hargreaves
James R Hargreaves
CBChristopher P Bonell
Christopher P Bonell
TBTania Boler
Tania Boler
DBDelia Boccia
Delia Boccia
IBIsolde Birdthistle
Isolde Birdthistle
JGJudith R Glynn
Judith R Glynn
To assess the evidence that the association between educational attainment and risk of HIV infection is changing over time in sub-Saharan Africa. Systematic review of published peer-reviewed articles. Articles were identified that reported original data comparing individually measured educational attainment and HIV status among at least 300 individuals representative of the general population of countries or regions of sub-Saharan Africa. Statistical analyses were required to adjust for potential confounders but not over-adjust for variables on the causal pathway. Approximately 4000 abstracts and 1200 full papers were reviewed. Thirty-six articles were included in the study, containing data on 72 discrete populations from 11 countries between 1987 and 2003, representing over 200,000 individuals. Studies on data collected prior to 1996 generally found either no association or the highest risk of HIV infection among the most educated. Studies conducted from 1996 onwards were more likely to find a lower risk of HIV infection among the most educated. Where data over time were available, HIV prevalence fell more consistently among highly educated groups than among less educated groups, in whom HIV prevalence sometimes rose while overall population prevalence was falling. In several populations, associations suggesting greater HIV risk in the more educated at earlier time points were replaced by weaker associations later. HIV infections appear to be shifting towards higher prevalence among the least educated in sub-Saharan Africa, reversing previous patterns. Policy responses that ensure HIV-prevention measures reach all strata of society and increase education levels are urgently needed.

1 November 2019 in The Lancet Global Health
Verified
Journal Article
Open access
IBIsolde Birdthistle
Isolde Birdthistle
CTClare Tanton
Clare Tanton
ATAndrew Tomita
Andrew Tomita
KGKristen de Graaf
Kristen de Graaf
SSSusie Schaffnit
Susie Schaffnit
ESEmma Slaymaker
Emma Slaymaker
The roll-out of antiretroviral therapy (ART) has changed contexts of HIV risk, but the influence on HIV incidence among young women is not clear. We aimed to summarise direct estimates of HIV incidence among adolescent girls and young women since ART and before large investments in targeted prevention for those in sub-Saharan Africa. We did a systematic review and meta-analysis. We searched MEDLINE, Embase, Web of Science, Global Health, and CINAHL for studies reporting HIV incidence data from serological samples collected among females aged 15-24 years in ten countries (Kenya, Lesotho, Malawi, Mozambique, South Africa, Swaziland, Tanzania, Uganda, Zambia, and Zimbabwe) that were selected for DREAMS investment in 2015. We only included articles published in English. Our main outcome was to summarise recent levels and trends in HIV incidence estimates collected between 2005 and 2015, published or received from study authors, by age and sex, and pooled by region. 51 studies were identified from nine of the ten DREAMS countries; no eligible studies from Lesotho were identified. Directly observed HIV incidence rates were lowest among females aged 13-19 years in Kumi, Uganda (0·38 cases per 100 person-years); and directly observed HIV incidence rates were highest in KwaZulu-Natal, South Africa (7·79 per 100 person-years among females aged 15-19 years, and 8·63 in those aged 20-24 years), among fishing communities in Uganda (12·40 per 100 person-years in females aged 15-19 years and 4·70 in those aged 20-24 years), and among female sex workers aged 18-24 years in South Africa (13·20 per 100 person-years) and Zimbabwe (10·80). In pooled rates from the general population studies, the greatest sex differentials were in the youngest age groups-ie, females aged 15-19 years compared with male peers in both southern African (pooled relative risk 5·94, 95% CI 3·39-10·44) and eastern African countries (3·22, 1·51-6·87), and not significantly different among those aged 25-29 years in either region. Incidence often peaked earlier (during teenage years) among high-risk groups compared with general populations. Since 2005, HIV incidence among adolescent girls and young women declined in Rakai (Uganda) and Manicaland (Zimbabwe), and also declined among female sex workers in Kenya, but not in the highest-risk communities in South Africa and Uganda. Few sources of direct estimates of HIV incidence exist in high-burden countries and trend analyses with disaggregated data for age and sex are rare but indicate recent declines among adolescent girls and young women. In some of the highest-risk settings, however, little evidence exists to suggest ART availability and other efforts slowed transmission by 2016. Despite wide geographical diversity in absolute levels of incidence in adolescent girls and young women, risk relative to males persisted in all settings, with the greatest sex differentials in the youngest age groups. To end new infections among the growing population of adolescents in sub-Saharan Africa, prevention programmes must address gender inequalities driving excessive risk among adolescent girls. This work was conducted as part of a planning grant funded by the Bill & Melinda Gates Foundation.

11 February 2014 in BMC Medical Research Methodology
Verified
Journal Article
Open access
PDF file
AGAnnabelle Gourlay
Annabelle Gourlay
GMGerry Mshana
Gerry Mshana
IBIsolde Birdthistle
Isolde Birdthistle
GBGrace Bulugu
Grace Bulugu
BZBasia Zaba
Basia Zaba
MUMark Urassa
Mark Urassa
Background: Vignettes are short stories about a hypothetical person, traditionally used within research (quantitative or qualitative) on sensitive topics in the developed world. Studies using vignettes in the developing world are emerging, but with no critical examination of their usefulness in such settings. We describe the development and application of vignettes to a qualitative investigation of barriers to uptake of prevention of mother-to-child transmission (PMTCT) HIV services in rural Tanzania in 2012, and critique the successes and challenges of using the technique in this setting. Methods: Participatory Learning and Action (PLA) group activities (3 male; 3 female groups from Kisesa, north-west Tanzania) were used to develop a vignette representing realistic experiences of an HIV-infected pregnant woman in the community. The vignette was discussed during in-depth interviews with 16 HIV-positive women, 3 partners/relatives, and 5 HIV-negative women who had given birth recently. A critical analysis was applied to assess the development, implementation and usefulness of the vignette. Results: The majority of in-depth interviewees understood the concept of the vignette and felt the story was realistic, although the story or questions needed repeating in some cases. In-depth interviewers generally applied the vignette as intended, though occasionally were unsure whether to steer the conversation back to the vignette character when participants segued into personal experiences. Interviewees were occasionally confused by questions and responded with what the character should do rather than would do; also confusing fieldworkers and presenting difficulties for researchers in interpretation. Use of the vignette achieved the main objectives, putting most participants at ease and generating data on barriers to PMTCT service uptake. Participants’ responses to the vignette often reflected their own experience (revealed later in the interviews). Conclusions: Participatory group research is an effective method for developing vignettes. A vignette was incorporated into qualitative interview discussion guides and used successfully in rural Africa to draw out barriers to PMTCT service use; vignettes may also be valuable in HIV, health service use and drug adherence research in this setting. Application of this technique can prove challenging for fieldworkers, so thorough training should be provided prior to its use.

30 March 2008 in AIDS
Verified
Journal Article
Closed access
IBIsolde Birdthistle
Isolde Birdthistle
SFSian Floyd
Sian Floyd
AMAuxillia Machingura
Auxillia Machingura
NMNetsai Mudziwapasi
Netsai Mudziwapasi
SGSimon Gregson
Simon Gregson
JGJudith R Glynn
Judith R Glynn
Background: Despite the 15 million children orphaned by AIDS, and fears of sexual vulnerability, little is known about the link between orphanhood and HIV risk. Methods: A random sample of 1283 15 to 19-year-old girls in a high-density suburb of Harare was identified in a cross-sectional survey in 2004. A total of 863 agreed to be interviewed and 839 provided a specimen for HIV and herpes simplex virus type-2 (HSV-2) testing. Sexual health outcomes, sexual behaviours and marriage were assessed by type and timing of orphanhood. Results: Half of the participants were single or double orphans. Prevalence of HIV and/or HSV-2 was higher among orphans than non-orphans [17 versus 12%; age-adjusted odds ratio (aOR) = 1.5; 95% confidence interval (CI) 1.0–2.3]. Associations with orphan status were only significant among the 743 never-married participants. In comparison with non-orphaned peers, increased sexual risk (defined as HSV2-positive, HIV-positive or ever pregnant) was seen among maternal orphans (aOR = 3.6; 95% CI, 1.7–7.8), double orphans (aOR = 2.4; 95% CI, 1.2–4.9), and girls who lost their father before age 12 (aOR = 2.1; 95% CI, 0.9–4.8) but not later (aOR = 0.8; 95% CI, 0.3–2.2). Maternal and double orphans were most likely to initiate sex early and to have had multiple partners. Maternal orphans were least likely to have used a condom at first sex, and to have a regular sexual partner. Experience of forced sex was high in all groups. Conclusions: In urban Zimbabwe, female adolescent orphans are at increased risk of HIV and HSV-2 infection. Infection rates vary by type and age of orphanhood, and marital status, and are associated with high-risk sexual behaviours.

25 July 2018 in BMC Public Health
Verified
Journal Article
Open access
PDF file
IBIsolde Birdthistle
Isolde Birdthistle
SSSusie Schaffnit
Susie Schaffnit
DKDaniel Kwaro
Daniel Kwaro
MSMaryam Shahmanesh
Maryam Shahmanesh
ZZZiraba Ziraba
Ziraba Ziraba
SFSian Floyd
Sian Floyd
HIV risk remains unacceptably high among adolescent girls and young women (AGYW) in southern and eastern Africa, reflecting structural and social inequities that drive new infections. In 2015, PEPFAR (the United States President’s Emergency Plan for AIDS Relief) with private-sector partners launched the DREAMS Partnership, an ambitious package of interventions in 10 sub-Saharan African countries. DREAMS aims to reduce HIV incidence by 40% among AGYW over two years by addressing multiple causes of AGYW vulnerability. This protocol outlines an impact evaluation of DREAMS in four settings. To achieve an impact evaluation that is credible and timely, we describe a mix of methods that build on longitudinal data available in existing surveillance sites prior to DREAMS roll-out. In three long-running surveillance sites (in rural and urban Kenya and rural South Africa), the evaluation will measure: (1) population-level changes over time in HIV incidence and socio-economic, behavioural and health outcomes among AGYW and young men (before, during, after DREAMS); and (2) causal pathways linking uptake of DREAMS interventions to ‘mediators’ of change such as empowerment, through to behavioural and health outcomes, using nested cohort studies with samples of ~ 1000–1500 AGYW selected randomly from the general population and followed for two years. In Zimbabwe, where DREAMS includes an offer of pre-exposure HIV prophylaxis (PrEP), cohorts of young women who sell sex will be followed for two years to measure the impact of ‘DREAMS+PrEP’ on HIV incidence among young women at highest risk of HIV. In all four settings, process evaluation and qualitative studies will monitor the delivery and context of DREAMS implementation. The primary evaluation outcome is HIV incidence, and secondary outcomes include indicators of sexual behavior change, and social and biological protection. DREAMS is, to date, the most ambitious effort to scale-up combinations or ‘packages’ of multi-sectoral interventions for HIV prevention. Evidence of its effectiveness in reducing HIV incidence among AGYW, and demonstrating which aspects of the lives of AGYW were changed, will offer valuable lessons for replication.