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Dive into the research topics where Helen Ward is active.

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Featured researches published by Helen Ward.


The Lancet | 1997

Epidemics of syphilis in the Russian Federation: trends, origins, and priorities for control

L Tichonova; K. K. Borisenko; Helen Ward; André Meheus; A. Gromyko; Adrian Renton

After continuous decline throughout the 1980s, surveillance-defined estimates of the incidence of syphilis in Russia have shown a rapid and substantial increase during the 1990s. The reasons for this epidemic are unclear, but must be sought among changes both in sexual behaviour and in the patterns of provision, use, and effectiveness of diagnostic, treatment, and contact tracing services. High incidence of sexually transmitted disease causes correspondingly high levels of morbidity and suffering as well as significant health-care and other economic costs. Our current understanding suggests that the transmissibility of HIV is increased by infection with sexually transmitted disease. The syphilis epidemic together with changes in sexual behaviour, increased travel and migration, and rapid increases in injecting drug use may create the conditions for an epidemic of sexually acquired HIV infection in Russia that substantially outstrips those encountered in most Western European countries.


Current Opinion in Hiv and Aids | 2010

Contribution of sexually transmitted infections to the sexual transmission of HIV.

Helen Ward; Minttu Rönn

Purpose of reviewWe review recent evidence about the link between sexually transmitted infections (STI) and HIV transmission and consider implications for control programmes. Recent findingsNew studies and meta-analyses confirm the association of HIV acquisition and transmission with recent STIs, although there is considerable heterogeneity between organisms and populations. Much of the recent evidence relates to herpes simplex virus type 2 (HSV-2), for which the population-attributable risk percentage (PAR%) for HSV-2 is between 25 and 35 in Africa. Mathematical models show how transmission attributable to STI varies with HIV epidemic phase, and HSV-2 becomes increasingly important as the epidemic matures. HSV-2 suppressive therapy reduces HIV concentrations in plasma and the genital tract in people coinfected with HSV-2, in part due to direct inhibition of HIV reverse transcriptase. Recent trials of HSV-2 suppressive therapy have not shown an impact on the risk of HIV acquisition, nor in controlling transmission from dually infected people to their serodiscordant heterosexual partners. SummaryAlthough there is a plausible link between STI and HIV risk, intervention studies continue to be disappointing. This fact does not disprove a causal link, but mechanisms of action and the design and implementation of interventions need to be better understood.


Neuroendocrinology | 2002

The Hypothalamic Mechanisms of the Hypophysiotropic Action of Ghrelin

Alison M. Wren; Caroline J. Small; Charlotte V. Fribbens; Nicola M. Neary; Helen Ward; Leighton J. Seal; Mohammad A. Ghatei; Stephen R. Bloom

Ghrelin is an endogenous ligand for the growth hormone secretagogue (GHS) receptor, expressed in the hypothalamus and pituitary. Ghrelin, like synthetic GHSs, stimulates food intake and growth hormone (GH) release following systemic or intracerebroventricular administration. In addition to GH stimulation, ghrelin and synthetic GHSs are reported to stimulate the hypothalamo-pituitary-adrenal (HPA) axis in vivo. The aims of this study were to elucidate the hypothalamic mechanisms of the hypophysiotropic actions of ghrelin in vitro and to assess the relative contribution of hypothalamic and systemic actions of ghrelin on the HPA axis in vivo. Ghrelin (100 and 1,000 nM) stimulated significant release of GH-releasing hormone (GHRH) from hypothalamic explants (100 nM: 39.4 ± 8.3 vs. basal 18.3 ± 3.5 fmol/explant, n = 49, p < 0.05) but did not affect either basal or 28 mM KCl-stimulated somatostatin release. Ghrelin (10, 100 and 1,000 nM) stimulated the release of both corticotropin-releasing hormone (CRH) (100 nM: 6.0 ± 0.8 vs. basal 4.2 ± 0.5 pmol/explant, n = 49, p < 0.05) and arginine vasopressin (AVP) (100 nM: 49.2 ± 5.9 vs. basal 35.0 ± 3.3 fmol/explant, n = 48, p < 0.05), whilst ghrelin (100 and 1,000 nM) also stimulated the release of neuropeptide Y (NPY) (100 nM: 111.4 ± 25.0 vs. basal 54.4 ± 9.0 fmol/explant, n = 26, p < 0.05) from hypothalamic explants in vitro. The HPA axis was stimulated in vivo following acute intracerebroventricular administration of ghrelin 2 nmol [adrenocorticotropic hormone (ACTH) 38.2 ± 3.9 vs. saline 18.2 ± 2.0 pg/ml, p < 0.01; corticosterone 310.1 ± 32.8 ng/ml vs. saline 167.4 ± 40.7 ng/ml, p < 0.05], but not following intraperitoneal administration of ghrelin 30 nmol, suggesting a hypothalamic site of action. These data suggest that the mechanisms of GH and ACTH regulation by ghrelin may include hypothalamic release of GHRH, CRH, AVP and NPY.


BMJ | 2009

Assessing the severity of the novel influenza A/H1N1 pandemic

Tini Garske; Judith Legrand; Christl A. Donnelly; Helen Ward; Simon Cauchemez; Christophe Fraser; Neil M. Ferguson; Azra C. Ghani

A major concern about the emergence of the novel strain of influenza A/H1N1 is the severity of illness it causes. Tini Garske and colleagues propose methods to obtain accurate estimates of the case fatality ratio as the pandemic unfolds


Clinical Infectious Diseases | 2007

Lymphogranuloma venereum in the United kingdom.

Helen Ward; Iona M. C. Martin; N Macdonald; Sarah Alexander; Ian Simms; Kevin A. Fenton; Patrick French; Gillian Dean; C Ison

BACKGROUND Over the past 2 years, lymphogranuloma venereum (LGV), caused by L serovars of Chlamydia trachomatis, has emerged as a significant problem among men who have sex with men (MSM). We report on, to our knowledge, the largest case series of LGV to date, with detailed epidemiological and clinical characteristics of the epidemic in the United Kingdom. METHODS A national diagnostic service and surveillance system was established in October 2004. Cases were confirmed by the presence of C. trachomatis and an LGV serovar (L1, L2, or L3) from genotyping. For confirmed cases, an enhanced surveillance questionnaire was sent to the clinician. RESULTS Through February 2006, a total of 327 cases of LGV were confirmed. Cases were diagnosed across the United Kingdom, with the majority from London (71%) and Brighton (13%). Case reports were received for 282 MSM. The majority (96%) had proctitis, many with severe local and systemic symptoms. There was a high level of coinfection with human immunodeficiency virus (76%), hepatitis C (19%), and other sexually transmitted infections (39%). Nine cases of human immunodeficiency virus infection were diagnosed around the same time as LGV. Most cases were acquired within the United Kingdom, although patients with early cases were more likely to report contacts in The Netherlands. CONCLUSIONS We found a significant burden of this once-rare sexually transmitted infection among MSM in the United Kingdom. LGV may be contributing to the epidemic of human immunodeficiency virus infection by facilitating transmission. Further control efforts are required, including awareness campaigns, continued detailed surveillance, and expanded chlamydia testing among MSM.


Hiv Medicine | 2009

Reductions in HIV transmission risk behaviour following diagnosis of primary HIV infection: a cohort of high-risk men who have sex with men.

Julie Fox; Peter White; N Macdonald; Jonathan Weber; Myra O. McClure; Sarah Fidler; Helen Ward

Risk‐reduction counselling is a standard preventive intervention, but behaviour change is difficult to sustain over the duration of HIV infection. However, primary HIV infection (PHI) is highly infectious and plays a key role in transmission – especially through dense sexual networks – but is short term, so even transient risk reduction can mitigate its high infectivity. Targeting behaviour‐change interventions at recently infected individuals may be highly effective, particularly in higher risk groups. We explored the potential impact on HIV transmission‐risk behaviour of PHI diagnosis in men who have sex with men (MSM).


AIDS | 2014

Adherence to antiretroviral therapy in adolescents living with HIV: systematic review and meta-analysis

Sung-Hee Kim; Sarah Gerver; Sarah Fidler; Helen Ward

Objective:Adolescent and young adult (AYA) populations (12–24 years) represent over 40% of new HIV infections globally. Adolescence is sometimes characterized by high-risk sexual behaviour and a lack of engagement with healthcare services that can affect adherence to antiretroviral therapy (ART). Despite adherence to ART being critical in controlling viral replication, maintaining health and reducing onward viral transmission, there are limited data on ART adherence amongst AYA globally. We undertook a systematic review and meta-analysis of published studies reporting adherence to ART for AYA living with HIV. Design and methods:Searches included Embase, Medline and PsychINFO databases up to 14 August 2013. Eligible studies defined adequate adherence as at least 85% on self-report or undetectable blood plasma virus levels. A random effects meta-analysis was performed and heterogeneity examined using meta-regression. Results:We identified 50 eligible articles reporting data from 53 countries and 10 725 patients. Using a pooled analysis of all eligible studies, 62.3% [95% confidence interval (CI) 57.1–67.6; I2 : 97.2%] of the AYA population were adherent to therapy. The lowest average ART adherence was in North America [53% (95% CI 46–59; I2 : 91%)], Europe [62% (95% CI 51–73; I2 : 97%)] and South America [63% (95% CI 47–77; I2 : 85%] and, with higher levels in Africa [84% (95% CI 79–89; I2 : 93%)] and Asia [84% (95% CI 77–91; I2 : 0%]. Conclusion:Review of published literature from Africa and Asia indicate more than 70% of HIV-positive AYA populations receiving ART are adherent to therapy and lower rates of adherence were shown in Europe and North America at 50–60%. The global discrepancy is probably multifactorial reflecting differences between focused and generalised epidemics, access to healthcare and funding.


Sexually Transmitted Infections | 2009

Rectal chlamydia - a reservoir of undiagnosed infection in men who have sex with men.

Naa Torshie Annan; Ann Sullivan; Achyuta Nori; Polia Naydenova; Sarah Alexander; Alex McKenna; B Azadian; Sundhiya Mandalia; Marco Rossi; Helen Ward; Nneka Nwokolo

Objective: To determine the prevalence of rectal chlamydia infection in a cohort of men who have sex with men (MSM) and the proportion of infection that would be missed without routine screening. Methods: MSM presenting to four HIV/GUM outpatient clinics at the Chelsea & Westminster Hospital NHS Foundation Trust between 1 November 2005 and 29 September 2006 were offered testing for rectal chlamydia infection in addition to their routine screen for sexually transmitted infections (STIs). Chlamydia trachomatis (CT) tests were performed using the Beckton-Dickinson Probe-Tec Strand Displacement Assay. Positive samples were re-tested at the Sexually Transmitted Bacteria Reference Laboratory, to confirm the result and identify lymphogranuloma venereum (LGV)-associated serovars. Results: A total of 3076 men were screened. We found an 8.2% prevalence of infection with CT (LGV and non-LGV serovars) in the rectum and 5.4% in the urethra. The HIV and rectal chlamydia co-infection rate was 38.1%. The majority of rectal infections (69.2%, (171/247)) were asymptomatic and would have been missed if routine screening had not been undertaken. Of the samples re-tested, 94.2% (227/242) rectal and 91.8% (79/86) urethral specimens were confirmed CT positive and 36 cases of LGV were identified. Conclusion: Our data show a high rate of rectal chlamydia infection, in the majority of cases it was asymptomatic. We recommend routine screening for rectal chlamydia in men at risk, as this may represent an important reservoir for the onward transmission of infection.


The Journal of Infectious Diseases | 1998

Effect on Normal Vaginal Flora of Three Intravaginal Microbicidal Agents Potentially Active against Human Immunodeficiency Virus Type 1

Isobel Rosenstein; Michael K. Stafford; Valerie S. Kitchen; Helen Ward; Jonathan Weber; David Taylor-Robinson

The effect on normal vaginal flora of three intravaginal microbicides potentially active against human immunodeficiency virus type 1 was examined. Volunteers received dextrin sulfate (D2S), nonoxynol-9 (N-9), or docusate sodium in separate placebo-controlled studies. High vaginal swabs were obtained for bacterial culture before and after microbicide application. D2S did not affect the vaginal flora. However, lactobacilli decreased by > or = 10(2) cfu/mL in 9 (56%) of 16 women given N-9 and in 5 (63%) of 8 women given docusate sodium. Women using N-9 were also significantly more likely to become colonized abnormally (usually with aerobic gram-negative rods) than were those using placebo, as were women using docusate sodium. Women with reduced lactobacilli were less likely to regain normal flora than were those whose lactobacilli were unaffected. However, coliform colonization occurred whether lactobacilli produced H2O2 or not. Continuous use of N-9 could induce susceptibility to urinary and gynecological infection. It is essential that potential microbicides are examined for activity against normal vaginal flora.


Sexually Transmitted Infections | 2009

The prevalence of lymphogranuloma venereum infection in men who have sex with men: results of a multicentre case finding study

Helen Ward; Sarah Alexander; Caroline Carder; Gillian Dean; Patrick French; Dan Ivens; Clare Ling; John Paul; William Tong; John White; C Ison

Objective: To determine the prevalence of lymphogranuloma venereum (LGV) and non-LGV associated serovars of urethral and rectal Chlamydia trachomatis (CT) infection in men who have sex with men (MSM). Design: Multicentre cross-sectional survey. Setting: Four genitourinary medicine clinics in the United Kingdom from 2006–7. Subjects: 4825 urethral and 6778 rectal samples from consecutive MSM attending for sexual health screening. Methods: Urethral swabs or urine and rectal swabs were tested for CT using standard nucleic acid amplification tests. Chlamydia-positive specimens were sent to the reference laboratory for serovar determination. Main outcome: Positivity for both LGV and non-LGV associated CT serovars; proportion of cases that were symptomatic. Results: The positivity (with 95% confidence intervals) in rectal samples was 6.06% (5.51% to 6.66%) for non-LGV CT and 0.90% (0.69% to 1.16%) for LGV; for urethral samples 3.21% (2.74% to 3.76%) for non-LGV CT and 0.04% (0.01% to 0.16%) for LGV. The majority of LGV was symptomatic (95% of rectal, one of two urethral cases); non-LGV chlamydia was mostly symptomatic in the urethra (68%) but not in the rectum (16%). Conclusions: Chlamydial infections are common in MSM attending for sexual health screening, and the majority are non-LGV associated serovars. We did not identify a large reservoir of asymptomatic LGV in the rectum or urethra. Testing for chlamydia from the rectum and urethra should be included for MSM requesting a sexual health screen, but serovar-typing is not indicated in the absence of symptoms. We have yet to identify the source of most cases of LGV in the UK.

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Peter White

Imperial College London

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C Ison

Health Protection Agency

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Minttu Rönn

Imperial College London

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Ian Simms

Public Health England

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