T Charles Witzel

Mr. T Charles Witzel


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

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

Representative Publications

View All Publications
3 December 2020 in BMC Medicine
Verified
Journal Article
Open access
PDF file
TWT Charles Witzel
T Charles Witzel
IEIngrid Eshun-Wilson
Ingrid Eshun-Wilson
MJMuhammad S. Jamil
Muhammad S. Jamil
NTNerissa Tilouche
Nerissa Tilouche
CFCarmen Figueroa
Carmen Figueroa
PWPeter Weatherburn
Peter Weatherburn
Background: We update a previous systematic review to inform new World Health Organization HIV self-testing (HIVST) recommendations. We compared the effects of HIVST to standard HIV testing services to understand which service delivery models are effective for key populations. Methods: We did a systematic review of randomised controlled trials (RCTs) which compared HIVST to standard HIV testing in key populations, published from 1 January 2006 to 4 June 2019 in PubMed, Embase, Global Index Medicus, Social Policy and Practice, PsycINFO, Health Management Information Consortium, EBSCO CINAHL Plus, Cochrane Library and Web of Science. We extracted study characteristic and outcome data and conducted risk of bias assessments using the Cochrane ROB tool version 1. Random effects meta-analyses were conducted, and pooled effect estimates were assessed along with other evidence characteristics to determine the overall strength of the evidence using GRADE methodology. Results: After screening 5909 titles and abstracts, we identified 10 RCTs which reported on testing outcomes. These included 9679 participants, of whom 5486 were men who have sex with men (MSM), 72 were trans people and 4121 were female sex workers. Service delivery models included facility-based, online/mail and peer distribution. Support components were highly diverse and ranged from helplines to training and supervision. HIVST increased testing uptake by 1.45 times (RR=1.45 95% CI 1.20, 1.75). For MSM and small numbers of trans people, HIVST increased the mean number of HIV tests by 2.56 over follow-up (mean difference = 2.56; 95% CI 1.24, 3.88). There was no difference between HIVST and SoC in regard to positivity among tested overall (RR = 0.91; 95% CI 0.73, 1.15); in sensitivity analysis of positivity among randomised HIVST identified significantly more HIV infections among MSM and trans people (RR = 2.21; 95% CI 1.20, 4.08) and in online/mail distribution systems (RR = 2.21; 95% CI 1.14, 4.32). Yield of positive results in FSW was not significantly different between HIVST and SoC. HIVST reduced linkage to care by 17% compared to SoC overall (RR = 0.83; 95% CI 0.74, 0.92). Impacts on STI testing were mixed; two RCTs showed no decreases in STI testing while one showed significantly lower STI testing in the intervention arm. There were no negative impacts on condom use (RR = 0.95; 95% CI 0.83, 1.08), and social harm was very rare. Conclusions: HIVST is safe and increases testing uptake and frequency as well as yield of positive results for MSM and trans people without negative effects on linkage to HIV care, STI testing, condom use or social harm. Testing uptake was increased for FSW, yield of positive results were not and linkage to HIV care was worse. Strategies to improve linkage to care outcomes for both groups are crucial for effective roll-out.

9 September 2016 in PLOS ONE
Verified
Journal Article
Open access
PDF file
TWT Charles Witzel
T Charles Witzel
ARAlison J Rodger
Alison J Rodger
FBFiona M Burns
Fiona M Burns
TRTim Rhodes
Tim Rhodes
PWPeter Weatherburn
Peter Weatherburn
Innovative strategies, such as HIV self-testing (HIVST), could increase HIV testing rates and diagnosis. Evidence to inform the design of an HIVST intervention in the UK is scarce with very little European data on this topic. This study aims to understand values and preferences for HIVST interventions targeting MSM in the UK. We explore the acceptability of HIVST among MSM in the context of known barriers and facilitators to testing for HIV; assess preferences for, and the concerns about, HIVST. Six focus group discussions (FGD) were conducted with 47 MSM in London, Manchester and Plymouth. HIVST as a concept was discussed and participants were asked to construct their ideal HIVST intervention. OraQuickTM and BioSureTM kits were then demonstrated and participants commented on procedure, design and instructions. FGDs were recorded and transcribed verbatim, then analysed thematically. Convenience and confidentiality of HIVST was seen to facilitate testing. Issues with domestic privacy problematised confidentiality. HIVST kits and instructions were thought to be unnecessarily complicated, and did not cater to the required range of abilities. The window period was the most important element of an HIVST, with strong preference for 4th generation testing. Kits which used a blood sample were more popular than those using saliva due to higher perceived accuracy although phobia of needles and/or blood meant some would only access HIVST if a saliva sample option was available. A range of access options was important to maintain convenience and privacy. HIVST kits were assumed to increase frequency of testing, with concerns related to the dislocation of HIVST from sexual health care pathways and services. Utility of HIVST arises from relatively high levels of confidentiality and convenience. Until 4th generation assays are available HIVST will be seen as supplementary in a UK context.

14 September 2016 in BMJ Open
Verified
Journal Article
Open access
PDF file
TWT Charles Witzel
T Charles Witzel
GMG J Melendez-Torres
G J Melendez-Torres
FHFord Hickson
Ford Hickson
PWPeter Weatherburn
Peter Weatherburn
Objectives The British HIV Association's (BHIVA) testing guidelines recommend men who have sex with men (MSM) test annually or more frequently if ongoing risk is present. We identify which groups of MSM in England are less likely to have tested for HIV and their preferences for future tests by testing model, in order to inform health promotion programmes. Methods Data come from the Gay Men's Sex Survey 2014, a cross-sectional survey of MSM, aged 16 years or older and living in the UK. Only men who did not have diagnosed HIV and were living in England were included in this analysis. We used logistic regression models to understand how social determinants of health were associated with not testing for HIV in the past 12 months, and never having tested. We then cross-tabulated preferred testing location by demographic characteristics. Results Younger men, older men and men who were not gay identified were least likely to have tested for HIV. Higher educational attainment, migrancy, Black ethnicity and being at higher of risk were associated with greater levels of HIV testing. Men who were less likely to have tested for HIV preferred a wider range of options for future HIV testing. Conclusions If the BHIVA's HIV testing policy of 2008 was used to guide testing priorities among MSM focus would be on increasing the rate of annual testing among MSM at less risk of HIV (ie, younger men, older men and non-gay identified MSM). Instead the promotion of more frequent testing among the groups most at risk of infection should be prioritised in order to reduce the time between infection and diagnosis.

12 March 2024 in eClinicalMedicine
Verified
Journal Article
Open access
TWT Charles Witzel
T Charles Witzel
AGAndrew Ghobrial
Andrew Ghobrial
RPRomain Palich
Romain Palich
HCHannah Charles
Hannah Charles
ARAlison J. Rodger
Alison J. Rodger
JSJohn Saunders
John Saunders
The 2022–2024 global mpox outbreak, occurring primarily in the sexual networks of gay, bisexual and other men who have sex with men (GBMSM), has not been accompanied by a focus on patient perspectives of illness. We explore the experiences of GBMSM diagnosed with mpox in England to understand needs for social and clinical support. In-depth interviews (March/July 2023) were conducted with 22 GBMSM diagnosed with mpox in 2022, randomly selected from a national mpox surveillance database, and 4 stakeholders from clinical/community-based organisations. Interviews covered experiences of illness, testing, diagnosis, treatment and contact tracing, and were recorded, transcribed and analysed with a thematic framework. Media coverage drawing on homophobic stereotypes around sex between men contributed to feelings of stigma and shame. GBMSM living with HIV appeared to cope better with mpox stigma, drawing on their experiences of being diagnosed with HIV for resilience. Younger GBMSM with less experience of stigmatising illness found mpox diagnosis more traumatic and sometimes required support beyond what was provided. Accessing testing could be complicated when healthcare professionals did not recognise mpox symptoms. Men felt information on course of illness, isolation and vaccination after recovery was often inconsistent and contradictory. GBMSM described that care from sexual health and infectious disease units usually better met their emotional and medical needs. This was frequently linked by men to these services having skills in working with the GBMSM community and managing infection risk sensitively. General hospital services and centralised contact tracing could increase feelings and experiences of stigma as some staff were perceived to lack skills in supporting GBMSM and, sometimes, clinical knowledge. Long-term impacts described by men included mental health challenges, urethral/rectal symptoms and life-changing disability. In this study stigma was a central feature of mpox illness among GBMSM and could be exacerbated or lessened depending on the clinical and social support provided. Involving communities affected by outbreaks in co-producing, planning and delivering care (including contact-tracing) may help improve support provided. TCW, AJR, AS and FMB received support from the 10.13039/501100000272 National Institute for Health and Care Research (NIHR) under its Programme Grants for Applied Research Programme (Ref: NIHR202038). CS and JS receive support from the National Institute for Health and Care Research Health Protection Research Unit (NIHR HPRU) in Blood Borne and Sexually Transmitted Infections at UCL in partnership with UKHSA; RV receives support from the NIHR HPRU in Emerging and Zoonotic Infections and NIHR HPRU in Gastrointestinal Infections. The views expressed are those of the author(s) and not necessarily those of the 10.13039/501100000272 NIHR , UK Health Security Agency, 10.13039/100004423 World Health Organization or the 10.13039/501100000276 Department of Health and Social Care .

23 April 2021 in Journal of Medical Internet Research
Verified
Journal Article
Open access
RMRebecca Meiksin
Rebecca Meiksin
GMG J Melendez-Torres
G J Melendez-Torres
JFJane Falconer
Jane Falconer
TWT Charles Witzel
T Charles Witzel
PWPeter Weatherburn
Peter Weatherburn
CBChris Bonell
Chris Bonell
Background: Men who have sex with men (MSM) face disproportionate risks concerning HIV and other sexually transmitted infections, substance use, and mental health. These outcomes constitute an interacting syndemic among MSM; interventions addressing all 3 together could have multiplicative effects. eHealth interventions can be accessed privately, and evidence from general populations suggests these can effectively address all 3 health outcomes. However, it is unclear how useable, accessible, or acceptable eHealth interventions are for MSM and what factors affect this. Objective: We undertook a systematic review of eHealth interventions addressing sexual risk, substance use, and common mental illnesses among MSM and synthesized evidence from process evaluations. Methods: We searched 19 databases, 3 trials registers, OpenGrey, and Google, and supplemented this by reference checks and requests to experts. Eligible reports were those that discussed eHealth interventions offering ongoing support to MSM aiming to prevent sexual risk, substance use, anxiety or depression; and assessed how intervention delivery or receipt varied with characteristics of interventions, providers, participants, or context. Reviewers screened citations on titles, abstracts, and then full text. Reviewers assessed quality of eligible studies, and extracted data on intervention, study characteristics, and process evaluation findings. The analysis used thematic synthesis. Results: A total of 12 reports, addressing 10 studies of 8 interventions, were eligible for process synthesis. Most addressed sexual risk alone or with other outcomes. Studies were assessed as medium and high reliability (reflecting the trustworthiness of overall findings) but tended to lack depth and breadth in terms of the process issues explored. Intervention acceptability was enhanced by ease of use; privacy protection; use of diverse media; opportunities for self-reflection and to gain knowledge and skills; and content that was clear, interactive, tailored, reflective of MSM’s experiences, and affirming of sexual-minority identity. Technical issues and interventions that were too long detracted from acceptability. Some evidence suggested that acceptability varied by race or ethnicity and educational level; findings on variation by socioeconomic status were mixed. No studies explored how intervention delivery or receipt varied by provider characteristics. Conclusions: Findings suggest that eHealth interventions targeting sexual risk, substance use, and mental health are acceptable for MSM across sociodemographic groups. We identified the factors shaping MSM’s receipt of such interventions, highlighting the importance of tailored content reflecting MSM’s experiences and of language affirming sexual-minority identities. Intervention developers can draw on these findings to increase the usability and acceptability of integrated eHealth interventions to address the syndemic of sexual risk, substance use, and mental ill health among MSM. Evaluators of these interventions can draw on our findings to plan evaluations that explore the factors shaping usability and acceptability.

1 February 2021 in eClinicalMedicine
Verified
Journal Article
Open access
TWT Charles Witzel
T Charles Witzel
TWTalen Wright
Talen Wright
LMLeanne McCabe
Leanne McCabe
MGMichelle M. Gabriel
Michelle M. Gabriel
AWAedan Wolton
Aedan Wolton
ARAlison J. Rodger
Alison J. Rodger
Globally, trans people are disproportionately affected by HIV, but research on strategies to increase testing are limited. SELPHI is a randomised-controlled-trial (RCT) of 10,135 cis men, trans men, and trans women reporting lifetime anal intercourse with male partners (cis or trans), evaluating whether the offer of free HIV self-testing (HIVST) increases diagnosis. This subgroup analysis from the SELPHI RCT aims to describe key HIVST outcomes and HIVST acceptability for trans people. SELPHI recruited using social networking and trans focused social media. Participants were randomised 60/40 to baseline HIVST (Biosure™) (BT) vs no baseline HIVST (nBT); and at 3-months (if completed the survey and reported recent CAI) 50/50 to 3-monthly HIVST (RT) vs no repeat HIVST (nRT). Outcomes were self-reported through online surveys. We conducted a qualitative study of semi-structured peer-led participant interviews (n = 20) exploring HIVST motivations and experiences. These were analysed using a framework approach. SELPHI recruited and randomised 118 trans men and trans women (94 trans men, 24 trans women), of whom 20 (16 trans men, 4 trans women) underwent the second randomisation. Median age at baseline was 29 (IQR: 22, 37), 79% were white, 79% were UK born, 37% had degree level education, and 31% had never tested for HIV. 62% (n = 59) of trans men completed the 3-month survey, but survey completion by trans women in nBT was too low (1/11) for randomised comparison. In trans men HIV testing uptake by 3 months was significantly higher in BT (95% 36/38) vs nBT (29%, 6/21) (RR=3.32 (1.68, 6.55) p<0.001). Trans people randomised to RT reported 3 times higher rate of HIV testing compared to nRT during the two-year follow-up (IRR 3.66 (1.86, 8.01) p<0.0001). STI testing frequency (mean number of tests during each 13 week period/ 2-year follow-up) was not significantly different across interventions: RT (0.03) and nRT (0.01) (IRR=1.86 95%CI; 0.77, 5.15; p = 0.15). Social harms were rare. Acceptability was very high in BT: 97% (38/39) found instructions easy to understand, 97% (37/38) found the HIVST simple to use and 100% (39/39) reported good overall experience. In interviews, reported HIVST benefits included increased autonomy, privacy, convenience and avoidance of health care providers perceived to be discriminatory and services that increased dysphoria. Minor lancet and test processing issues were reported. HIVST significantly increased testing uptake and frequency in trans men and trans people overall, although recruitment and retention of trans women was low. HIVST acceptability was high and indicates easy access to this novel technology may increase HIV testing access for this key population.