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Featured researches published by John V. Parry.


BMJ | 2000

Prevalence of antibodies to hepatitis B, hepatitis C, and HIV and risk factors in Irish prisoners: results of a national cross sectional survey.

Shane Allwright; Fiona Bradley; Jean Long; Joseph Barry; Lelia Thornton; John V. Parry

Abstract Objectives: To determine the prevalence of antibodies to hepatitis B core antigen, hepatitis C virus, and HIV in the prison population of the Republic of Ireland and to examine risk factors for infection. Design: Cross sectional, anonymous, unlinked survey, with self completed risk factor questionnaire and provision of oral fluid specimen for antibody testing. Setting: Nine of the 15 prisons in the Republic of Ireland. Participants: 1366 prisoners, of whom 1205 (57 women) participated. In the smaller prisons all prisoners were surveyed, while in the three largest prisons one half of the population was randomly sampled. Three small prisons believed not to have a problem with injecting drug use were excluded. Main outcome measures: Prevalence of antibodies to hepatitis B core antigen, antibodies to hepatitis C virus, and antibodies to HIV. Self reported risk factor status. Results: Prevalence of antibodies to hepatitis B core antigen was 104/1193 (8.7%; 95% confidence interval 7.2% to 10.5%), to hepatitis C virus, 442/1193 (37%; 34.3% to 39.9%), and to HIV, 24/1193 (2%; 1.3% to 3%). The most important predictor of being positive for hepatitis B and hepatitis C was a history of injecting drug use. Thirty four women (60%) and 474 men (42%) reported ever injecting drugs. A fifth (104) of 501 injecting drug users reported first injecting in prison, and 347 (71%) users reported sharing needles in prison. Conclusions: Infection with hepatitis C secondary to use of injected drugs is endemic in Irish prisons. Better access to harm reduction strategies is needed in this environment.


Addiction | 2011

The impact of needle and syringe provision and opiate substitution therapy on the incidence of Hepatitis C virus in injecting drug users: pooling of UK evidence.

Katherine Mary Elizabeth Turner; Sharon J. Hutchinson; Peter Vickerman; Vivian Hope; Noel Craine; Norah Palmateer; Margaret T May; Avril Taylor; Daniela De Angelis; S. Cameron; John V. Parry; Margaret Lyons; David J. Goldberg; Elizabeth Allen; Matthew Hickman

AIMS To investigate whether opiate substitution therapy (OST) and needle and syringe programmes (NSP) can reduce hepatitis C virus (HCV) transmission among injecting drug users (IDUs). DESIGN Meta-analysis and pooled analysis, with logistic regression allowing adjustment for gender, injecting duration, crack injecting and homelessness. SETTING Six UK sites (Birmingham, Bristol, Glasgow, Leeds, London and Wales), community recruitment. PARTICIPANTS A total of 2986 IDUs surveyed during 2001-09. MEASUREMENT Questionnaire responses were used to define intervention categories for OST (on OST or not) and high NSP coverage (≥100% versus <100% needles per injection). The primary outcome was new HCV infection, measured as antibody seroconversion at follow-up or HCV antibody-negative/RNA-positive result in cross-sectional surveys. FINDINGS Preliminary meta-analysis showed little evidence of heterogeneity between the studies on the effects of OST (I2=48%, P=0.09) and NSP (I2=0%, P=0.75), allowing data pooling. The analysis of both interventions included 919 subjects with 40 new HCV infections. Both receiving OST and high NSP coverage were associated with a reduction in new HCV infection [adjusted odds ratios (AORs)=0.41, 95% confidence interval (CI): 0.21-0.82 and 0.48, 95% CI: 0.25-0.93, respectively]. Full harm reduction (on OST plus high NSP coverage) reduced the odds of new HCV infection by nearly 80% (AOR=0.21, 95% CI: 0.08-0.52). Full harm reduction was associated with a reduction in self-reported needle sharing by 48% (AOR 0.52, 95% CI: 0.32-0.83) and mean injecting frequency by 20.8 injections per month (95% CI: -27.3 to -14.4). CONCLUSIONS There is good evidence that uptake of opiate substitution therapy and high coverage of needle and syringe programmes can substantially reduce the risk of hepatitis C virus transmission among injecting drug users. Research is now required on whether the scaling-up of intervention exposure can reduce and limit hepatitis C virus prevalence in this population.


BMJ | 2005

Incidence of hepatitis C virus and HIV among new injecting drug users in London: prospective cohort study

Ali Judd; Matthew Hickman; Steve Jones; Tamara McDonald; John V. Parry; Gerry V. Stimson; Andrew J. Hall

In England, the low prevalence of HIV among injecting drug users during the 1990s was attributed in part to the introduction of harm reduction interventions in the late 1980s. Also, the prevalence of hepatitis C virus in the late 1990s was thought to be relatively low compared with other countries, at around 40% overall and 15% among those who had been injecting drugs for less than six years.1 We carried out a prospective cohort study of new injecting drug users in London to estimate the incidence of hepatitis C virus and HIV. In 2001, we recruited from community settings mainly in London, but also in Brighton, 428 injecting drug users who were aged below 30 years or had been injecting for six years or fewer. All had injected in the previous four weeks and could provide addresses for follow up. They completed interviewer administered questionnaires and provided oral fluid specimens and optionally dried capillary blood spots for testing for antibodies to hepatitis C virus and HIV using published methods.2 3 They were followed up 12 months later. …


AIDS | 2002

Explosive spread and high prevalence of Hiv infection among injecting drug users in Togliatti City, Russia

Tim Rhodes; Catherine M. Lowndes; Ali Judd; Larissa Mikhailova; Anya Sarang; A Rylkov; M Tichonov; K Lewis; N Ulyanova; T Alpatova; Karavashkin; Mikhail Khutorskoy; Matthew Hickman; John V. Parry; Adrian Renton

ObjectiveTo establish the prevalence of antibodies to HIV (anti-HIV) and associated risk factors among injecting drug users (IDU) in Togliatti City, Samara Oblast, Russian Federation. DesignAn unlinked anonymous cross-sectional community recruited survey with oral fluid sample collection. MethodsBetween September and October 2001, 426 IDU were recruited by trained fieldworkers. Participants completed an interviewer administered questionnaire, and oral fluid samples were tested for anti-HIV. Univariate and multivariate analyses compared potential risk factors for anti-HIV. ResultsAnti-HIV prevalence was 56% (234/418). Three-quarters of anti-HIV-positive IDU (74%) were unaware of their positive status. In an adjusted model, the odds of HIV infection were higher among IDU who had ever injected home-produced drugs, who reported injecting with used needles and syringes in the past 4 weeks, and who were living in one particular district of the city (Komsomolksii). ConclusionThe high prevalence of HIV, and a recent increase in HIV detected through routine screening tests since 2000, suggests that an explosive epidemic has occurred among IDU in Togliatti City. In the face of currently inadequate HIV prevention coverage among IDU, this has urgent implications for maximizing the distribution of sterile injecting equipment as well as for enhancing sexual risk reduction. Recognizing that it is likely that similar explosive epidemics are taking place in other Russian cities, we recommend community-wide HIV prevention coverage supported by city and state policies oriented to harm reduction.


BMJ | 2001

Prevalence of antibodies to hepatitis B, hepatitis C, and HIV and risk factors in entrants to Irish prisons: a national cross sectional survey

Jean Long; Shane Allwright; Joseph Barry; Sheilagh Reaper-Reynolds; Lelia Thornton; Fiona Bradley; John V. Parry

Abstract Objectives: To determine the prevalence of antibodies to hepatitis B core antigen, hepatitis C virus, and HIV in entrants to Irish prisons and to examine risk factors for infection. Design: Cross sectional, anonymous survey, with self completed risk factor questionnaire and oral fluid specimen for antibody testing. Setting: Five of seven committal prisons in the Republic of Ireland. Participants: 607 of the 718 consecutive prison entrants from 6 April to 1 May 1999. Main outcome measures: Prevalence of antibodies to hepatitis B core antigen, hepatitis C virus, and HIV in prison entrants, and self reported risk factor status. Results: Prevalence of antibodies to hepatitis B core antigen was 37/596 (6%; 95% confidence interval 4% to 9%), to hepatitis C virus was 130/596 (22%; 19% to 25%), and to HIV was 12/596 (2%; 1% to 4%). A third of the respondents had never previously been in prison; these had the lowest prevalence of antibodies to hepatitis B core antigen (4/197, 2%), to hepatitis C (6/197, 3%), and to HIV (0/197). In total 29% of respondents (173/593) reported ever injecting drugs, but only 7% (14/197) of those entering prison for the first time reported doing so compared with 40% (157/394) of those previously in prison. Use of injected drugs was the most important predictor of antibodies to hepatitis B core antigen and hepatitis C virus. Conclusions: Use of injected drugs and infection with hepatitis C virus are endemic in Irish prisons. A third of prison entrants were committed to prison for the first time. Only a small number of first time entrants were infected with one or more of the viruses. These findings confirm the need for increased infection control and harm reduction measures in Irish prisons. What is already known on this topic High rates of using injected drugs, initiation of use of injected drugs, and sharing of injecting equipment occur in Irish prisons Injecting drug users have high rates of infection with hepatitis B and C viruses, and hepatitis C is endemic in injecting drug users and in Irish prisoners What this study adds The prevalence of antibodies to hepatitis B core antigen, to hepatitis C, and to HIV in prison entrants who had previously been imprisoned was similar to that found in the recent national survey of Irish prisoners, but the prevalence of these antibodies was much lower in the third of prison entrants who had never previously been in prison Tattooing in prison is an independent risk factor for hepatitis C infection in prisoners who have never used injected drugs


AIDS | 2010

Determinants of HIV-1 transmission in men who have sex with men: a combined clinical, epidemiological and phylogenetic approach

Martin Fisher; David Pao; Alison E. Brown; Darshan Sudarshi; O Noel Gill; Patricia A. Cane; Andrew J. Buckton; John V. Parry; Anne M Johnson; Caroline Sabin; Deenan Pillay

Objectives:To identify biological factors associated with HIV transmission in men who have sex with men (MSM). Design:A longitudinal phylogenetic analysis of HIV-1 from an MSM cohort, incorporating clinical and epidemiological data. Methods:Potential individuals were HIV-infected MSM attending a sexual health clinic between 2000 and 2006. Individuals were classified such that they could move from recent to chronic infection categories. HIV-1 pol gene sequences were obtained from plasma virus or proviral DNA and clusters estimated by maximum likelihood and conservative genetic distance differences. The single most likely transmitter generating each recent infection was ascertained and risk factors around time of likely transmission explored using Poisson regression modelling. Results:Out of 1144 HIV-infected MSM, pol sequence data were obtained for 859 (75%); 159 out of 859 (19%) were recently HIV infected at diagnosis. A single most likely transmitter was identified for 41 out of 159 (26%), of which 11 were recently infected (27%) and 30 chronically infected. Factors associated with transmission in multivariable analysis were: younger age {rate ratio per 5 years older 0.68 [95% confidence interval (CI) 0.54–0.86], P = 0.0009}, higher viral load [rate ratio per log higher 1.61 (95% CI 1.15–2.25), P = 0.005], recent infection [rate ratio 3.88 (95% CI 1.76–8.55), P = 0.0008] and recent sexually transmitted disease [rate ratio 5.32 (95% CI 2.51–11.29), P = 0.0001]. HAART was highly protective in a univariable model, RR 0.14 (95% CI 0.07–0.27, P = 0.0001). Conclusion:Onward transmission of HIV among MSM is significantly associated with recent infection, sexually transmitted diseases and higher viral load, and reduced by effective HAART. The majority of new infections appear to occur from individuals whose infection was undiagnosed at the time of transmission.


Sexually Transmitted Infections | 2004

Increasing risk behaviour and high levels of undiagnosed HIV infection in a community sample of homosexual men

Julie Dodds; D Mercey; John V. Parry; Anne M Johnson

Objectives: To estimate changes in sexual behaviour over time. To examine the proportion of undiagnosed HIV infection in a community sample of homosexual men. To explore the relation between HIV status, diagnosis, and sexual behaviour. Methods: Five cross sectional surveys of men attending selected gay community venues in London between 1996 and 2000 (n = 8052). Men were recruited in 45 to 58 social venues (including bars, clubs, and saunas) across London. Participants self completed an anonymous behavioural questionnaire. In 2000, participants in community venues provided anonymous saliva samples for testing for anti-HIV antibody. Results: The proportion of men having unprotected anal intercourse (UAI) increased significantly each year from 30% in 1996 to 42% in 2000 (p<<0.001). In 2000, 132 of 1206 (10.9%) saliva samples were HIV antibody positive. Of the HIV saliva antibody positive samples, 43/132 (32.5%) were undiagnosed. Around half of both diagnosed and undiagnosed HIV saliva positive men reported UAI in the past year. Of the 83% of men who reported their current perceived HIV status, 4.1% reported an incorrect status. HIV antibody positivity was associated with increasing numbers of UAI partners, and having a sexually transmitted infection (STI) in the past year (OR 2.15). Conclusions: Homosexual men continue to report increasing levels of UAI. HIV prevalence is high in this group, with many infections remaining undiagnosed. The high level of risky behaviour in HIV positive men, regardless of whether they are diagnosed, is of public health concern, in an era when HIV prevalence, antiretroviral resistance, and STI incidence are increasing.


AIDS | 1994

Risk behaviour and HIV prevalence in international travellers

Sarah Hawkes; Graham Hart; Anne M Johnson; Carol Shergold; Emma Ross; Karen M. Herbert; Philip P. Mortimer; John V. Parry; David Mabey

ObjectiveTo assess risk factors for infection and to determine HIV prevalence in a sample of international travellers. DesignA cross-sectional survey of new patients attending a hospital outpatient clinic, and self-completion of an anonymous questionnaire on sexual behaviour prior to and during travel. Urine samples were tested for the presence of antibodies to HIV. SettingThe Hospital for Tropical Diseases, London, UK. SubjectsAll new patients over a 6-month period. ResultsOf 782 people approached, 757 (97%) agreed to participate: 141 (18.6%) had had new sexual partners during their most recent trip abroad. Almost two-thirds of those having sex abroad did not use condoms on every occasion with a new partner, and 5.7% contracted a sexually transmitted disease (STD) during their most recent trip; 26% of men from World Health Organization Pattern I countries who had new sexual partners abroad paid for sex. Sixteen out of 731 (2.2%) participants were HIV-antibody-positive. HIV positivity was associated with being born in east, central or southern Africa, having symptoms of an STD since arriving in the United Kingdom and being treated for an STD since arrival. ConclusionThe rates of unsafe sex and payment for sex abroad reported by these international travellers indicate the potential for contracting and transmitting STD, including HIV, in both their foreign and domestic sexual partnerships. With the increasing HIV incidence in Asia (the most common destination for UK travellers after sub-Saharan Africa), the number of cases of HIV contracted abroad may rise in the future.


Journal of Clinical Microbiology | 2004

Performance of Commercially Available Enzyme Immunoassays for Detection of Antibodies against Herpes Simplex Virus Type 2 in African Populations

Eddy. Van Dyck; Anne Buvé; Helen A. Weiss; Judith R. Glynn; David W. Brown; Bénédicte De Deken; John V. Parry; Richard Hayes

ABSTRACT Data are accumulating on the performance of enzyme immunoassays (EIAs) for the detection of herpes simplex virus type 2 (HSV-2) infection in North America and Europe, but little is known about their performance in other populations. Nine test kits were evaluated with 330 serum samples from sub-Saharan Africa. The tests were first compared to the monoclonal antibody (MAb) EIA (Central Public Health Laboratory, London, United Kingdom). Samples that gave discordant results in the MAb EIA and in the three tests that performed best compared to the MAb EIA were tested by Western blotting (University of Washington, Seattle). A random sample of concordant samples was also tested, and the sensitivities and specificities of the different tests were calculated, taking into account this sampling strategy. The sensitivities of the tests ranged from 86 to 100%; the specificities ranged from 47 to 99%. The tests that performed best were the Gull Premier EIA (sensitivity, 86.3%; specificity, 97.6%) and the Kalon Biological (sensitivity, 92.3%; specificity, 97.7%) and Biokit (sensitivity, 86.7%; specificity, 92.6%) tests. It cannot be assumed that enzyme immunoassays for the detection of HSV-2 infection that perform well in industrialized countries will perform equally well in other populations.


Journal of Viral Hepatitis | 2008

Increasing the uptake of hepatitis C virus testing among injecting drug users in specialist drug treatment and prison settings by using dried blood spots for diagnostic testing: a cluster randomized controlled trial

Matthew Hickman; Tamara McDonald; Ali Judd; T. Nichols; Hope; S Skidmore; John V. Parry

Summary.  The objective of this study was to assess whether introducing dried blood spot testing can increase hepatitis C virus (HCV) diagnostic testing. A cluster randomized controlled trial was conducted. Sites were matched into pairs, with one site in each pair randomly allocated to receive the intervention (training and use of dried blood spot). Data were collected from all sites for 6 months before and 6 months after the start of the intervention. The participants were 22 specialist drug clinics and six prisons in England and Wales. The main outcome measure of this study was percentage point difference in individuals tested for HCV (the difference between the percentage of patients tested 6 months after and 6 months before the introduction of dried blood spot tests). Before the trial, 8% of patients at control and intervention sites had been tested for HCV, with 16 sites testing less than 5% of their caseload. The average percentage point difference between intervention and control sites was 14.5% (95% CI 1.3–28%, paired t‐test, P = 0.03); with 13 of the 14 pairs contributing to the positive effect of the intervention (Wilcoxon matched‐pairs signed‐rank‐test, P = 0.002). The size of the difference between intervention and control sites varied considerably. The study provides preliminary supporting evidence that dried blood spot testing may increase the uptake of HCV diagnostic testing, by increasing the opportunity for patients to be offered testing. Additional trials with a larger number of sites are justified, ideally in the context of drug and treatment policies that gave clearer priority (and targets) to infection control and testing.

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Vivian Hope

Liverpool John Moores University

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Ali Judd

University College London

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Gary Murphy

Health Protection Agency

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Keith R. Perry

Public health laboratory

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