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The Lancet | 2013

Prevalence, risk factors, and uptake of interventions for sexually transmitted infections in Britain: findings from the National Surveys of Sexual Attitudes and Lifestyles (Natsal).

Pam Sonnenberg; Soazig Clifton; Simon Beddows; Nigel Field; Kate Soldan; Clare Tanton; Catherine H Mercer; Filomeno da Silva; Sarah Alexander; Andrew Copas; Andrew Phelps; Bob Erens; Philip Prah; Wendy Macdowall; Kaye Wellings; Catherine A Ison; Anne M Johnson

Summary Background Population-based estimates of prevalence, risk distribution, and intervention uptake inform delivery of control programmes for sexually transmitted infections (STIs). We undertook the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) after implementation of national sexual health strategies, and describe the epidemiology of four STIs in Britain (England, Scotland, and Wales) and the uptake of interventions. Methods Between Sept 6, 2010 and Aug 31, 2012, we did a probability sample survey of 15u2008162 women and men aged 16–74 years in Britain. Participants were interviewed with computer-assisted face-to-face and self-completion questionnaires. Urine from a sample of participants aged 16–44 years who reported at least one sexual partner over the lifetime was tested for the presence of Chlamydia trachomatis, type-specific human papillomavirus (HPV), Neisseria gonorrhoeae, and HIV antibody. We describe age-specific and sex-specific prevalences of infection and intervention uptake, in relation to demographic and behavioural factors, and explore changes since Natsal-1 (1990–91) and Natsal-2 (1999–2001). Findings Of 8047 eligible participants invited to provide a urine sample, 4828 (60%) agreed. We excluded 278 samples, leaving 4550 (94%) participants with STI test results. Chlamydia prevalence was 1·5% (95% CI 1·1–2·0) in women and 1·1% (0·7–1·6) in men. Prevalences in individuals aged 16–24 years were 3·1% (2·2–4·3) in women and 2·3% (1·5–3·4) in men. Area-level deprivation and higher numbers of partners, especially without use of condoms, were risk factors. However, 60·4% (45·5–73·7) of chlamydia in women and 43·3% (25·9–62·5) in men was in individuals who had had one partner in the past year. Among sexually active 16–24-year-olds, 54·2% (51·4–56·9) of women and 34·6% (31·8–37·4) of men reported testing for chlamydia in the past year, with testing higher in those with more partners. High-risk HPV was detected in 15·9% (14·4–17·5) of women, similar to in Natsal-2. Coverage of HPV catch-up vaccination was 61·5% (58·2–64·7). Prevalence of HPV types 16 and 18 in women aged 18–20 years was lower in Natsal-3 than Natsal-2 (5·8% [3·9–8·6] vs 11·3% [6·8–18·2]; age-adjusted odds ratio 0·44 [0·21–0·94]). Gonorrhoea (<0·1% prevalence in women and men) and HIV (0·1% prevalence in women and 0·2% in men) were uncommon and restricted to participants with recognised high-risk factors. Since Natsal-2, substantial increases were noted in attendance at sexual health clinics (from 6·7% to 21·4% in women and from 7·7% to 19·6% in men) and HIV testing (from 8·7% to 27·6% in women and from 9·2% to 16·9% in men) in the past 5 years. Interpretation STIs were distributed heterogeneously, requiring general and infection-specific interventions. Increases in testing and attendance at sexual health clinics, especially in people at highest risk, are encouraging. However, STIs persist both in individuals accessing and those not accessing services. Our findings provide empirical evidence to inform future sexual health interventions and services. Funding Grants from the UK Medical Research Council and the Wellcome Trust, with support from the Economic and Social Research Council and the Department of Health.


Lancet Infectious Diseases | 2013

Decreased susceptibility to cephalosporins among gonococci: data from the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) in England and Wales, 2007–2011

Catherine A Ison; Katy Town; Chinelo Obi; Stephanie A. Chisholm; Gwenda Hughes; David M. Livermore; Catherine M Lowndes

BACKGROUNDnEffective treatment of gonorrhoea is fundamental to public health control; however, the ability of Neisseria gonorrhoeae to successively develop resistance to different treatments has hampered control efforts. The extended-spectrum cephalosporins--cefixime and ceftriaxone--have been recommended in the UK for treatment of gonorrhoea since 2005. We looked at surveillance data from England and Wales to ascertain the current usefulness of these drugs and to inform changes to national treatment guidelines.nnnMETHODSnWe obtained data from the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP) for patients attending 26 genitourinary medicine clinics in England and Wales between 2007 and 2011. We did analyses with univariate and multivariable logistic regression methods to identify trends in susceptibility to cephalosporins and risk factors associated with infection with isolates with decreased susceptibility to cefixime, and we assessed changes in prescribing practices. We did molecular typing to investigate genetic relatedness of non-susceptible isolates.nnnFINDINGSnThe prevalence of decreased susceptibility to both cefixime and ceftriaxone rose between 2007 and 2010 but was more noticeable for cefixime (an increase from 1·5% in 2007 to 17·1% in 2010), with a bimodal distribution of minimum inhibitory concentration recorded between 2009 and 2010. By multivariable analysis, isolates with decreased susceptibility to cefixime were associated with infection in men who have sex with men (odds ratio 5·47, 95% CI 3·99-7·48; p<0·0001) and year of isolation (in 2010, 13·08, 7·49-22·8; p<0·0001). Such isolates had a largely clonal population, with most belonging to genogroup G1407 and harbouring the penA mosaic gene. Data from 2011 showed a significant decline in prevalence of isolates with decreased cefixime susceptibility, falling from 17·1% in 2010 to 10·8% in 2011 (p<0·0001), concomitant with the change in prescribing practice in 2010 from cefixime to ceftriaxone plus azithromycin.nnnINTERPRETATIONnGuidance for treatment of gonorrhoea in England and Wales was changed in 2010 to prolong the use of cephalosporins. The decline in prevalence of isolates with decreased cefixime susceptibility cannot be attributed unequivocally to this change in prescribing practice; however, the association is striking.nnnFUNDINGnDepartment of Health (England), Public Health England.


Sexually Transmitted Infections | 2008

Self-taken pharyngeal and rectal swabs are appropriate for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae in asymptomatic men who have sex with men

Sarah Alexander; Catherine A Ison; John V. Parry; Carrie Llewellyn; Sonali Wayal; Daniel Richardson; Alan Phillips; Helen Smith; Martin Fisher

Introduction: Self-taken specimens from men who have sex with men (MSM) could be important in reducing high levels of demand on sexual health services. The performance of self-taken specimens for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) from both pharyngeal and rectal sites in asymptomatic MSM was assessed. Methods: MSM were examined according to clinic protocol: a rectal and pharyngeal swab for GC culture and a rectal swab for the CT strand displacement assay. An extra set of nurse-taken and self-taken pharyngeal and rectal specimens were also requested and were tested using the Aptima Combo 2 assay and the result compared with the routine clinic result, which was considered the gold standard. Results: A total of 272 MSM was recruited and the sensitivity and specificity of nurse-taken and patient-taken swabs, respectively, was as follows: rectal GC: 94.9% and 90.1% (nurse); 92.3% and 87.9% (patient); pharyngeal GC: 88.2% and 91.8% (nurse); 100% and 87.8% (patient); rectal CT: 80.0% and 99.6% (nurse); 91.4% and 98.2% (patient). No significant difference in sensitivity or specificity was observed between the nurse-taken and the patient-taken rectal swabs for either GC or CT. For the detection of GC from the pharynx, comparable sensitivities were achieved between nurse-taken and patient-taken swabs (pu200a=u200a0.5); however, a significant difference in specificity was observed (pu200a=u200a0.006). This was due to a higher number of false GC-positive self-taken pharyngeal swabs from patients with high rates (90.9%; 10/11) of confirmed concurrent GC infection in different anatomical sites. Conclusions: MSM are able to collect self-taken rectal and pharyngeal swabs that are comparable to those taken by clinicians.


International Journal of Epidemiology | 2015

Epidemiology of Mycoplasma genitalium in British men and women aged 16–44 years: evidence from the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3)

Pam Sonnenberg; Catherine A Ison; Soazig Clifton; Nigel Field; Clare Tanton; Kate Soldan; Simon Beddows; Sarah Alexander; Rumena Khanom; Pamela Saunders; Andrew Copas; Kaye Wellings; Catherine H Mercer; Anne M Johnson

Background: There are currently no large general population epidemiological studies of Mycoplasma genitalium (MG), which include prevalence, risk factors, symptoms and co-infection in men and women across a broad age range. Methods: In 2010-–12, we conducted the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3), a probability sample survey in Britain. Urine from 4507 sexually-experienced participants, aged 16–44 years, was tested for MG. Results: MG prevalence was 1.2% [95% confidence interval (CI): 0.7–1.8%] in men and 1.3% (0.9–1.9%) in women. There were no positive MG tests in men aged 16–19, and prevalence peaked at 2.1% (1.2–3.7%) in men aged 25–34 years. In women, prevalence was highest in 16–19 year olds, at 2.4% (1.2–4.8%), and decreased with age. Men of Black ethnicity were more likely to test positive for MG [adjusted odds ratio (AOR) 12.1; 95% CI: 3.7–39.4). For both men and women, MG was strongly associated with reporting sexual risk behaviours (increasing number of total and new partners, and unsafe sex, in the past year). Women with MG were more likely to report post-coital bleeding (AOR 5.8; 95%CI 1.4–23.3). However, the majority of men (94.4%), and over half of women (56.2%) with MG did not report any sexually transmitted infection (STI) symptoms. Men with MG were more likely to report previously diagnosed gonorrhoea, syphilis or non-specific urethritis, and women previous trichomoniasis. Conclusions: This study strengthens evidence that MG is an STI. MG was identified in over 1% of the population, including in men with high-risk behaviours in older age groups that are often not included in STI prevention measures.


Sexually Transmitted Infections | 2013

Current and future treatment options for gonorrhoea

Catherine A Ison; Carolyn Deal; Magnus Unemo

The delivery of effective antimicrobial therapy is essential for public health control of gonorrhoea, in the absence of a suitable vaccine. The antimicrobial agent chosen should have high efficacy and quality, lack toxicity and give >95% success when given empirically. Guidelines, which are informed by surveillance data, are used to aid clinicians in their choice of appropriate agent. Historically, gonorrhoea treatment has been delivered as a single, directly observed dose but this has resulted in failure of successive antimicrobial agents which have been replaced by a new antimicrobial to which resistance has been rare or non-existing. Following the drift towards decreased susceptibility and treatment failure to the extended spectrum cephalosporins, and the lack of ‘new’ alternative antimicrobials, the threat of difficult to treat or untreatable gonorrhoea has emerged. The challenge of maintaining gonorrhoea as a treatable infection has resulted in national, regional and global response or action plans. This review discusses different approaches to the future treatment of gonorrhoea including; use of ceftriaxone, the injectable cephalosporin at increased dosage; dual antimicrobial therapy; use of drugs developed for other infections and use of older agents, directed by rapid point of care tests, to susceptible infections. Finally, it is considered whether the time is right to readdress the possibility of developing an effective gonococcal vaccine, given the major advances in our understanding of natural infection, molecular pathogenesis and the revolution in molecular biology techniques.


Eurosurveillance | 2014

Emerging cephalosporin and multidrug-resistant gonorrhoea in Europe

Michelle Cole; Gianfranco Spiteri; S A Chisholm; Steen Hoffmann; Catherine A Ison; Magnus Unemo; M J W van de Laar

Neisseria gonorrhoeae has consistently developed resistance to antimicrobials used therapeutically for gonorrhoea and few antimicrobials remain for effective empiric first-line therapy. Since 2009 the European gonococcal antimicrobial surveillance programme (Euro-GASP) has been running as a sentinel surveillance system across Member States of the European Union (EU) and European Economic Area (EEA) to monitor antimicrobial susceptibility in N. gonorrhoeae. During 2011, N. gonorrhoeae isolates were collected from 21 participating countries, and 7.6% and 0.5% of the examined gonococcal isolates had in vitro resistance to cefixime and ceftriaxone, respectively. The rate of ciprofloxacin and azithromycin resistance was 48.7% and 5.3%, respectively. Two (0.1%) isolates displayed high-level resistance to azithromycin, i.e. a minimum inhibitory concentration (MIC) ≥256 mg/L. The current report further highlights the public health need to implement the European response plan, including further strengthening of Euro-GASP, to control and manage the threat of multidrug resistant N. gonorrhoeae.


Sexually Transmitted Infections | 2013

The European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP)-a sentinel approach in the European Union (EU)/European Economic Area (EEA)

Gianfranco Spiteri; Michelle Cole; Magnus Unemo; Steen Hoffmann; Catherine A Ison; Marita van de Laar

Antimicrobial resistance in Neisseria gonorrhoeae is monitored in the European Union/European Economic Area through the European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP) coordinated by the European Centre for Disease Prevention and Control. Euro-GASP includes a sentinel surveillance programme which aims to detect in a timely manner changes in resistance patterns and inform treatment guidelines. The programme aims to test a representative number of isolates from each European Union/European Economic Area member state per year for a range of therapeutically relevant antimicrobials through a biannual hybrid centralised/decentralised system. Testing is supported by an External Quality Assurance programme and a laboratory training programme. Participation in the programme has increased to 21 countries in 2012. Euro-GASP has been able to detect the rapid spread of isolates with decreased susceptibility to cefixime across Europe in 2010 and 2011. Results from the programme have informed changes in European treatment guidelines for gonorrhoea and led to the development of the ‘Response plan to control and manage the threat of multidrug resistant gonorrhoea in Europe’. Future challenges for Euro-GASP include supporting countries to participate in Euro-GASP through decentralised testing, improving timeliness and epidemiological data quality, and increasing participation from Eastern Europe.


Sexually Transmitted Infections | 2013

Gonorrhoea and gonococcal antimicrobial resistance surveillance networks in the WHO European Region, including the independent countries of the former Soviet Union

Magnus Unemo; Catherine A Ison; Michelle Cole; Gianfranco Spiteri; Marita van de Laar; Lali Khotenashvili

Antimicrobial resistance (AMR) in Neisseria gonorrhoeae has emerged for essentially all antimicrobials following their introduction into clinical practice. During the latest decade, susceptibility to the last remaining options for antimicrobial monotherapy, the extended-spectrum cephalosporins (ESC), has markedly decreased internationally and treatment failures with these ESCs have been verified. In response to this developing situation, WHO and the European Centre for Disease Prevention and Control (ECDC) have published global and region-specific response plans, respectively. One main component of these action/response plans is to enhance the surveillance of AMR and treatment failures. This paper describes the perspectives from the diverse WHO European Region (53 countries), including the independent countries of the former Soviet Union, regarding gonococcal AMR surveillance networks. The WHO European Region has a high prevalence of resistance to all previously recommended antimicrobials, and most of the first strictly verified treatment failures with cefixime and ceftriaxone were also reported from Europe. In the European Union/European Economic Area (EU/EEA), the European gonococcal antimicrobial surveillance programme (Euro-GASP) funded by the ECDC is running. In 2011, the Euro-GASP included 21/31 (68%) EU/EEA countries, and the programme is further strengthened annually. However, in the non-EU/EEA countries, internationally reported and quality assured gonococcal AMR data are lacking in 87% of the countries and, worryingly, appropriate support for establishment of a GASP is still lacking. Accordingly, national and international support, including political and financial commitment, for gonococcal AMR surveillance in the non-EU/EEA countries of the WHO European Region is essential.


Sexually Transmitted Infections | 2016

Is chlamydia screening and testing in Britain reaching young adults at risk of infection? Findings from the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3)

Sarah C Woodhall; Kate Soldan; Pam Sonnenberg; Catherine H Mercer; Soazig Clifton; Pamela Saunders; Filomeno da Silva; Sarah Alexander; Kaye Wellings; Clare Tanton; Nigel Field; Andrew Copas; Catherine A Ison; Anne M Johnson

Background In the context of widespread opportunistic chlamydia screening among young adults, we aimed to quantify chlamydia testing and diagnosis among 16–24 year olds in Britain in relation to risk factors for prevalent chlamydia infection. Methods Using data from sexually experienced (≥1 lifetime sexual partner) 16-year-old to 24-year-old participants in Britains third National Survey of Sexual Attitudes and Lifestyles (conducted 2010–2012), we explored socio-demographic and behavioural factors associated with prevalent chlamydia infection (detected in urine; n=1832), self-reported testing and self-reported diagnosis in the last year (both n=3115). Results Chlamydia prevalence was 3.1% (95% CI 2.2% to 4.3%) in women and 2.3% (1.5% to 3.4%) in men. A total of 12.3% of women and 5.3% men had a previous chlamydia diagnosis. Factors associated with prevalent infection were also associated with testing and diagnosis (eg, increasing numbers of sexual partners), with some exceptions. For example, chlamydia prevalence was higher in women living in more deprived areas, whereas testing was not. In men, prevalence was higher in 20–24 than 16–19 year olds but testing was lower. Thirty per cent of women and 53.7% of men with ≥2 new sexual partners in the last year had not recently tested. Conclusions In 2010–2012 in Britain, the proportion of young adults reporting chlamydia testing was generally higher in those reporting factors associated with chlamydia. However, many of those with risk factors had not been recently tested, leaving potential for undiagnosed infections. Greater screening and prevention efforts among individuals in deprived areas and those reporting risk factors for chlamydia may reduce undiagnosed prevalence and transmission.


PLOS ONE | 2015

Home sampling for sexually transmitted infections and HIV in men who have sex with men: a prospective observational study

Martin Fisher; Sonali Wayal; Helen Smith; Carrie Llewellyn; Sarah Alexander; Catherine A Ison; John V. Parry; Garth Singleton; Nicky Perry; Daniel Richardson

To determine uptake of home sampling kit (HSK) for STI/HIV compared to clinic-based testing, whether the availability of HSK would increase STI testing rates amongst HIV infected MSM, and those attending a community-based HIV testing clinic compared to historical control. Prospective observational study in three facilities providing STI/HIV testing services in Brighton, UK was conducted. Adult MSM attending/contacting a GUM clinic requesting an STI screen (group 1), HIV infected MSM attending routine outpatient clinic (group 2), and MSM attending a community-based rapid HIV testing service (group 3) were eligible. Participants were required to have no symptomatology consistent with STI and known to be immune to hepatitis A and B (group 1). Eligible men were offered a HSK to obtain self-collected specimens as an alternative to routine testing. HSK uptake compared to conventional clinic-based STI/HIV testing in group 1, increase in STI testing rates due to availability of HSK compared to historical controls in group 2 and 3, and HSK return rates in all settings were calculated. Among the 128 eligible men in group 1, HSK acceptance was higher (62.5% (95% CI: 53.5–70.9)) compared to GUM clinic-based testing (37.5% (95% CI: 29.1–46.5)), (p = 0.0004). Two thirds of eligible MSM offered an HSK in all three groups accepted it, but HSK return rates varied (highest in group 1, 77.5%, lowest in group 3, 16%). HSK for HIV testing was acceptable to 81% of men in group 1. Compared to historical controls, availability of HSK increased the proportion of MSM testing for STIs in group 2 but not in group 3. HSK for STI/HIV offers an alternative to conventional clinic-based testing for MSM seeking STI screening. It significantly increases STI testing uptake in HIV infected MSM. HSK could be considered as an adjunct to clinic-based services to further improve STI/HIV testing in MSM.

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Nigel Field

University College London

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Anne M Johnson

University College London

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Clare Tanton

University College London

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Pam Sonnenberg

University College London

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Soazig Clifton

University College London

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