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Background: Workers across different occupations vary in their risk of SARS-CoV-2 infection, but the direct contribution of occupation to this relationship is unclear. This study aimed to investigate how infection risk differed across occupational groups in England and Wales up to April 2022, after adjustment for potential confounding and stratification by pandemic phase. Methods: Data from 15,190 employed/self-employed participants in the Virus Watch prospective cohort study were used to generate risk ratios for virologically- or serologically-confirmed SARS-CoV-2 infection using robust Poisson regression, adjusting for socio-demographic and health-related factors and non-work public activities. We calculated attributable fractions (AF) amongst the exposed for belonging to each occupational group based on adjusted risk ratios (aRR). Results: Increased risk was seen in nurses (aRR = 1.44, 1.25–1.65; AF = 30%, 20–39%), doctors (aRR = 1.33, 1.08–1.65; AF = 25%, 7–39%), carers (1.45, 1.19–1.76; AF = 31%, 16–43%), primary school teachers (aRR = 1.67, 1.42- 1.96; AF = 40%, 30–49%), secondary school teachers (aRR = 1.48, 1.26–1.72; AF = 32%, 21–42%), and teaching support occupations (aRR = 1.42, 1.23–1.64; AF = 29%, 18–39%) compared to office-based professional occupations. Differential risk was apparent in the earlier phases (Feb 2020—May 2021) and attenuated later (June—October 2021) for most groups, although teachers and teaching support workers demonstrated persistently elevated risk across waves. Conclusions: Occupational differences in SARS-CoV-2 infection risk vary over time and are robust to adjustment for socio-demographic, health-related, and non-workplace activity-related potential confounders. Direct investigation into workplace factors underlying elevated risk and how these change over time is needed to inform occupational health interventions. [ABSTRACT FROM AUTHOR]

Vaccination constitutes the best long-term solution against Coronavirus Disease-2019; however, vaccine-derived immunity may not protect all groups equally, and the durability of protective antibodies may be short. We evaluate Spike-antibody responses following BNT162b2 or ChAdOx1-S vaccination amongst SARS-CoV2-naive adults across England and Wales enrolled in a prospective cohort study (Virus Watch). Here we show BNT162b2 recipients achieved higher peak antibody levels after two doses; however, both groups experience substantial antibody waning over time. In 8356 individuals submitting a sample ≥28 days after Dose 2, we observe significantly reduced Spike-antibody levels following two doses amongst individuals reporting conditions and therapies that cause immunosuppression. After adjusting for these, several common chronic conditions also appear to attenuate the antibody response. These findings suggest the need to continue prioritising vulnerable groups, who have been vaccinated earliest and have the most attenuated antibody responses, for future boosters. Vaccination can provide reliable and long-lasting protection against COVID-19, however the immune response to vaccination can vary between individuals and can decline over time, leading to differences in protective effects. Here the authors assess the immune response to COVID-19 vaccination across a large cohort of previously uninfected adults and demonstrate lower post-vaccination antibody levels amongst those with immune-suppressing conditions and medications, as well as those with several other more common chronic conditions. [ABSTRACT FROM AUTHOR]

Background: Access to prevention options, including HIV pre-exposure prophylaxis (PrEP), remains a public health priority for gay, bisexual, and other men who have sex with men (MSM), especially in London. We describe PrEP use in a London community sample of MSM before the introduction of a national PrEP programme in October 2020.Methods: From June-August 2019, MSM aged ≥ 18 recruited from London commercial venues were asked to self-complete a sexual health questionnaire and provide an oral fluid sample for anonymous HIV antibody testing. Descriptive analyses of demographic characteristics, service engagement and outcomes, as well as sexual risk and prevention behaviours were examined in the survey population and in those reporting current PrEP use. We performed sequential, multivariate analyses examining current PrEP use in MSM of self-perceived HIV-negative/unknown status with identified PrEP-need defined as the report of condomless anal sex (CAS) in the last three months, or the report of CAS (in the last year) with an HIV-positive/unknown status partner not known to be on HIV treatment, in reflection of UK PrEP guidelines.Results: One thousand five hundred and thirty-fifth questionnaires were completed across 34 venues, where 1408 were analysed. One in five MSM of self-perceived HIV-negative/unknown status reported current PrEP use (19.7%, 242/1230). In men with PrEP-need, 68.2% (431/632) did not report current use. Current PrEP use was associated with age (aOR: 3.52, 95% CI: 1.76-7.02 in men aged 40-44 vs men aged 18-25) and education (aOR: 1.72, 95% CI: 1.01-2.92 in men with ≥ 2 years/still full-time vs no/ < 2 years of education since age 16).Conclusion: Among MSM in London, PrEP use is high but there is indication of unmet PrEP-need in men of younger age and lower levels of post-16 education. National programme monitoring and evaluation will require continued community monitoring to guide interventions ensuring equitable PrEP access and uptake in those who could most benefit from PrEP. [ABSTRACT FROM AUTHOR]

Objective: The aim of this report is to investigate the nature of the relationship between depression and condomless sex (CLS) among gay, bisexual and other men who have sex with men (GBMSM).Methods: Data are from the Antiretrovirals, Sexual Transmission Risk and Attitude (ASTRA) study of people living with HIV and attending one of eight HIV outpatient clinics in England (2011-2012) and the Attitudes to and Understanding of Risk of Acquisition of HIV (AURAH) study of HIV-negative/unknown status individuals attending one of 20 genitourinary medicine clinics in England (2013-2014). This analysis included GBMSM only. For each study, the prevalence of depressive symptoms (Patient Health Questionnaire-9 score ≥10) was presented according to three categories of sex in the past 3 months (considering anal/vaginal sex with men/women and anal sex with men in separate definitions): (1) no sex, (2) condom-protected sex only and (3) CLS. Multinomial logistic regression with 'condom-protected sex only' as the reference group was used to adjust for age and (for ASTRA participants) time since HIV diagnosis.Results: There were opposing associations of depression with recent sexual behaviour: the prevalence of depression was higher among those who reported no sex and those who reported CLS, compared with those who reported condom-protected sex only. Among the 2170 HIV-positive GBMSM in ASTRA, considering anal/vaginal sex with men/women, the prevalence of depressive symptoms was 32%, 20% and 28%, respectively, among men reporting no sex (n=783), condom-protected sex only (n=551) and CLS (n=836) (global p<0.001). Among the 1477 HIV-negative GBMSM in AURAH, the prevalence of depressive symptoms was 12%, 8% and 13%, respectively, for no sex (n=137), condom-protected sex only (n=487) and CLS (n=853) (global p=0.017). Patterns were similar after adjustment and when only considering anal sex between men.Conclusions: Depression may be linked both to lack of sexual activity and to sexual risk taking. When investigating associations between depression and CLS, it is important to separate out individuals reporting condom-protected sex only from those reporting no sex. [ABSTRACT FROM AUTHOR]

Aims: To investigate whether the introduction of minimum unit pricing (MUP) in Scotland on 1 May 2018 was reflected in changes in the likelihood of alcohol‐related queries submitted to an internet search engine, and in particular whether there was any evidence of increased interest in purchasing of alcohol from outside Scotland. Design Observational study in which individual queries to the internet Bing search engine for 2018 in Scotland and England were captured and analysed. Fluctuations over time in the likelihood of specific topic searches were examined. The patterns seen in Scotland were contrasted with those in England. Setting: Scotland and England. Participants: People who used the Bing search engine during 2018. Measurements Numbers of daily queries submitted to Bing in 2018 on eight alcohol‐related topics expressed as a proportion of queries on that day on any topic. These daily likelihoods were smoothed using a 14‐day moving average for Scotland and England separately. Findings There were substantial peaks in queries about MUP itself, cheap sources of alcohol and online alcohol outlets at the time of introduction of MUP in May 2018 in Scotland, but not England. These were relatively short‐lived. Queries related to intoxication and alcohol problems did not show a MUP peak, but were appreciably higher in Scotland than in England throughout 2018. Conclusions: Analysis of internet search engine queries appears to show that a fraction of people in Scotland may have considered circumventing minimum unit pricing in 2018 by looking for on‐line alcohol retailers. The overall higher levels of queries related to alcohol problems in Scotland compared with England mirrors the corresponding differences in alcohol consumption and harms between the countries. [ABSTRACT FROM AUTHOR]

Background: The extent of transmission of influenza in hospital settings is poorly understood. Next generation sequencing may improve this by providing information on the genetic relatedness of viral strains. Objectives: We aimed to apply next generation sequencing to describe transmission in hospital and compare with methods based on routinely‐collected data. Methods: All influenza samples taken through routine care from patients at University College London Hospitals NHS Foundation Trust (September 2012 to March 2014) were included. We conducted Illumina sequencing and identified genetic clusters. We compared nosocomial transmission estimates defined using classical methods (based on time from admission to sample) and genetic clustering. We identified pairs of cases with space‐time links and assessed genetic relatedness. Results: We sequenced influenza sampled from 214 patients. There were 180 unique genetic strains, 16 (8.8%) of which seeded a new transmission chain. Nosocomial transmission was indicated for 32 (15.0%) cases using the classical definition and 34 (15.8%) based on genetic clustering. Of the 50 patients in a genetic cluster, 11 (22.0%) had known space‐time links with other cases in the same cluster. Genetic distances between pairs of cases with space‐time links were lower than for pairs without spatial links (P < .001). Conclusions: Genetic data confirmed that nosocomial transmission contributes significantly to the hospital burden of influenza and elucidated transmission chains. Prospective next generation sequencing could support outbreak investigations and monitor the impact of infection and control measures. [ABSTRACT FROM AUTHOR]

Background: Opportunistic chlamydia screening of <25 year-olds was nationally-implemented in England in 2008 but its impact on chlamydia transmission is poorly understood. We undertook a population-based seroprevalence study to explore the impact of screening on cumulative incidence of chlamydia, as measured by C.trachomatis-specific antibody. Methods: Anonymised sera from participants in the nationally-representative Health Surveys for England (HSE) were tested for C.trachomatis antibodies using two novel Pgp3 enzyme-linked immunosorbent assays (ELISAs) as a marker of past infection. Determinants of being seropositive were explored using logistic regression among 16–44 year-old women and men in 2010 and 2012 (years when sexual behaviour questions were included in the survey) (n = 1,402 women; 1,119 men). Seroprevalence trends among 16–24 year-old women (n = 3,361) were investigated over ten time points from 1994–2012. Results: In HSE2010/2012, Pgp3 seroprevalence among 16–44 year-olds was 24.4% (95%CI 22.0–27.1) in women and 13.9% (11.8–16.2) in men. Seroprevalence increased with age (up to 33.5% [27.5–40.2] in 30–34 year-old women, 18.7% [13.4–25.6] in 35–39 year-old men); years since first sex; number of lifetime sexual partners; and younger age at first sex. 76.7% of seropositive 16–24 year-olds had never been diagnosed with chlamydia. Among 16–24 year-old women, a non-significant decline in seroprevalence was observed from 2008–2012 (prevalence ratio per year: 0.94 [0.84–1.05]). Conclusion: Our application of Pgp3 ELISAs demonstrates a high lifetime risk of chlamydia infection among women and a large proportion of undiagnosed infections. A decrease in age-specific cumulative incidence following national implementation of opportunistic chlamydia screening has not yet been demonstrated. We propose these assays be used to assess impact of chlamydia control programmes. [ABSTRACT FROM AUTHOR]

Objective To assess current and intended future use of pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM) and characterise those attending sexual health clinics, the anticipated PrEP delivery setting. Design Cross-sectional study. Methods Self-administered survey of 842 HIV negative MSM recruited from social venues in London in 2011. Results One in 10 (10.2%, 83/814, 95% CI 8.2% to 12.5%) and one in 50 (2.1%, 17/809, 95% CI 1.2% to 3.3%) reported having ever used post-exposure prophylaxis (PEP) and PrEP respectively. Half reported they would be likely to use PrEP if it became available as a daily pill (50.3%, 386/786, 95% CI 46.7% to 53.9%). MSM were more likely to consider future PrEP use if they were <35 years (adjusted OR (AOR) 1.57, 95% CI 1.16 to 2.14), had unprotected anal intercourse with casual partners (AOR 1.70, 95% CI 1.13 to 2.56), and had previously used PEP (AOR 1.94, 95% CI 1.17 to 3.24). Over half of MSM (54.8% 457/834 95% CI 51.3 to 58.2) attended a sexual health clinic the previous year. Independent factors associated with attendance were age <35 (AOR 2.29, 95% CI 1.68 to 3.13), and ≥10 anal sex partners in the last year (AOR 2.49, 95% CI 1.77 to 3.52). Conclusions The concept of PrEP for HIV prevention in the form of a daily pill is acceptable to half of sexually active MSM in London. MSM reporting higher risk behaviours attend sexual health clinics suggesting this is a suitable setting for PrEP delivery. [ABSTRACT FROM AUTHOR]

Background: Hard-to-reach population subgroups are typically investigated using convenience sampling, which may give biased estimates. Combining information from such surveys, a probability survey and clinic surveillance, can potentially minimize the bias. We developed a methodology to estimate the prevalence of undiagnosed HIV infection among men who have sex with men (MSM) in England and Wales aged 16-44 years in 2003, making fuller use of the available data than earlier work.Methods: We performed a synthesis of three data sources: genitourinary medicine clinic surveillance (11 380 tests), a venue-based convenience survey including anonymous HIV testing (3702 MSM) and a general population sexual behaviour survey (134 MSM). A logistic regression model to predict undiagnosed infection was fitted to the convenience survey data and then applied to the MSMs in the population survey to estimate the prevalence of undiagnosed infection in the general MSM population. This estimate was corrected for selection biases in the convenience survey using clinic surveillance data. A sensitivity analysis addressed uncertainty in our assumptions.Results: The estimated prevalence of undiagnosed HIV in MSM was 2.4% [95% confidence interval (95% CI 1.7-3.0%)], and between 1.6% (95% CI 1.1-2.0%) and 3.3% (95% CI 2.4-4.1%) depending on assumptions; corresponding to 5500 (3390-7180), 3610 (2180-4740) and 7570 (4790-9840) men, and undiagnosed fractions of 33, 24 and 40%, respectively.Conclusions: Our estimates are consistent with earlier work that did not make full use of data sources. Reconciling data from multiple sources, including probability-, clinic- and venue-based convenience samples can reduce bias in estimates. This methodology could be applied in other settings to take full advantage of multiple imperfect data sources. [ABSTRACT FROM AUTHOR]

Judith Stephenson and colleagues report on a cluster randomized trial in London of school-based peer-led sex education and whether it reduced unintended teenage pregnancy. [ABSTRACT FROM AUTHOR]

Objectives: To examine the geographical variations in HIV prevalence (diagnosed and undiagnosed), use of sexual health services, sexually transmitted infections and sexual behaviour in a community sample of men who have sex with men in three cities in England, specifically London, Brighton and Manchester.Methods: Cross-sectional surveys of men visiting gay community venues in three large cities in England. Men self-completed a questionnaire and provided an anonymous oral fluid sample for HIV antibody testing.Results: HIV prevalence ranged from 8.6% to 13.7% in the three cities. Over one-third of HIV infection remained undiagnosed in all sites despite 69% of HIV-positive men reporting attending a genitourinary medicine clinic in the last year. Similar and high levels of risk behaviour were reported in all three cities. 18% of HIV-negative men and 37% of HIV-positive men reported unprotected anal intercourse with more than one partner in the last year. 20% of negative men and 41% of positive men reported an STI in the last year.Conclusions: Across all cities, despite widespread availability of anti-retroviral treatment and national policy to promote HIV testing, many HIV infections remain undiagnosed. Data from this community sample demonstrate high levels of risk behaviour and STI incidence, especially among those who are HIV positive. Renewed efforts are needed to increase diagnosis and to reduce risk behaviour to stem the continuing transmission of HIV. [ABSTRACT FROM AUTHOR]

Background Our aim was to describe surveillance data on HIV transmission and risk behaviours in Camden and Islington, an inner London health district (population 360 000). This information is required to assess the effectiveness of HIV-AIDS prevention. [ABSTRACT FROM PUBLISHER]

Assesses the suitability of herpes simplex virus types 2 as a serological marker of sexual behavior in London population in England. Epidemiology of antibody to herpes simplex virus type 2; Association of antibody with sexual orientation and years of sexual activity of population; Prevalence of antibodies in herpes simplex virus type 2 among respondents. INSET: Epidemiological implications.

Background: In 2000, a 10-year Teenage Pregnancy Strategy was launched in England to reduce conceptions in women younger than 18 years and social exclusion in young parents. We used routinely collected data and data from Britain's National Surveys of Sexual Attitudes and Lifestyles (Natsal) to examine progress towards these goals.Methods: In this observational study, we used random-effects meta-regression to analyse the change in conception rates from 1994-98 to 2009-13 by top-tier local authorities in England, in relation to Teenage Pregnancy Strategy-related expenditure per head, socioeconomic deprivation, and region. Data from similar probability sample surveys: Natsal-1 (1990-91), Natsal-2 (1999-2001), and Natsal-3 (2010-12) were used to assess the prevalence of risk factors and their association with conception in women younger than 18 years in women aged 18-24 years; and the prevalence of participation in education, work, and training in young mothers.Findings: Conception rates in women younger than 18 years declined steadily from their peak in 1996-98 and more rapidly from 2007 onwards. More deprived areas and those receiving greater Teenage Pregnancy Strategy-related investment had higher rates of conception in 1994-98 and had greater declines to 2009-13. Regression analyses assessing the association between Teenage Pregnancy Strategy funding and decline in conception rates in women younger than 18 years showed an estimated reduction in the conception rate of 11.4 conceptions (95% CI 9.6-13.2; p<0.0001) per 1000 women aged 15-17 years for every £100 Teenage Pregnancy Strategy spend per head and a reduction of 8.2 conceptions (5.8-10.5; p<0.0001) after adjustment for socioeconomic deprivation and region. The association between conception in women younger than 18 years and lower socioeconomic status weakened slightly between Natsal-2 and Natsal-3. The prevalence of participation in education, work, or training among young women with a child conceived before age 18 years was low, but the odds of them doing so doubled between Natsal-2 and Natsal-3 (odds ratio 1.99, 95% CI 0.99-4.00).Interpretation: A sustained, multifaceted policy intervention involving health and education agencies, alongside other social and educational changes, has probably contributed to a substantial and accelerating decline in conceptions in women younger than 18 years in England since the late 1990s.Funding: Medical Research Council, Wellcome Trust, Economic and Social Research Council, and Department of Health. [ABSTRACT FROM AUTHOR]

The article compares trends in sexual risk among gay men in London, England and in Glasgow, Scotland. The trends in unprotected anal intercourse (UAI), UAI with partners of unknown/discordant HIV status and UAI with more than 1 partner were analyzed using multivariate logistic regression. Each rose significantly in 1999 and 2002 in London, but only in 2002 in Glasgow. HIV testing levels were lower in Glasgow, while sexual risk was higher in London.

Background: Chemsex (the use of psychoactive drugs in sexual contexts) has been associated with HIV acquisition and other STIs, so there is benefit in identifying those most likely to start chemsex to offer risk reduction interventions such as pre-exposure prophylaxis (PrEP). To date, there have been no data from a longitudinal study analysing factors most associated with starting and stopping chemsex., Methods: The prospective cohort study, Attitudes to and Understanding Risk of Acquisition of HIV over Time (AURAH2), collected 4 monthly and annual online questionnaire data from men who have sex with men (MSM) from 2015 to 2018. We investigate the association of sociodemographic factors, sexual behaviours and drug use with starting and stopping chemsex among 622 men who completed at least one follow-up questionnaire. Poisson models with generalised estimating equations were used to produce risk ratios (RRs) accounting for multiple starting or stopping episodes from the same individual. Multivariable analysis was adjusted for age group, ethnicity, sexual identity and university education., Findings: In the multivariable analysis, the under 40 age group was significantly more likely to start chemsex by the next assessment (RR 1.79, 95% CI 1.12 to 2.86). Other factors which showed significant association with starting chemsex were unemployment (RR 2.10, 95% CI 1.02 to 4.35), smoking (RR 2.49, 95% CI 1.63 to 3.79), recent condomless sex (CLS), recent STI and postexposure prophylaxis (PEP) use in the past year (RR 2.10, 95% CI 1.33 to 3.30). Age over 40 (RR 0.71, 95% CI 0.51 to 0.99), CLS, and use of PEP (RR 0.64, 95% CI 0.47 to 0.86) and PrEP (RR 0.47, 95% CI 0.29 to 0.78) were associated with lower likelihood of stopping chemsex by the next assessment., Interpretation: Knowledge of these results allows us to identify men most likely to start chemsex, thus providing an opportunity for sexual health services to intervene with a package of risk mitigation measures, especially PrEP use., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: The coronavirus (COVID-19) pandemic has caused significant global mortality and impacted lives around the world. Virus Watch aims to provide evidence on which public health approaches are most likely to be effective in reducing transmission and impact of the virus, and will investigate community incidence, symptom profiles and transmission of COVID-19 in relation to population movement and behaviours., Methods and Analysis: Virus Watch is a household community cohort study of acute respiratory infections in England and Wales and will run from June 2020 to August 2021. The study aims to recruit 50 000 people, including 12 500 from minority ethnic backgrounds, for an online survey cohort and monthly antibody testing using home fingerprick test kits. Nested within this larger study will be a subcohort of 10 000 individuals, including 3000 people from minority ethnic backgrounds. This cohort of 10 000 people will have full blood serology taken between October 2020 and January 2021 and repeat serology between May 2021 and August 2021. Participants will also post self-administered nasal swabs for PCR assays of SARS-CoV-2 and will follow one of three different PCR testing schedules based on symptoms., Ethics and Dissemination: This study has been approved by the Hampstead National Health Service (NHS) Health Research Authority Ethics Committee (ethics approval number 20/HRA/2320). We are monitoring participant queries and using these to refine methodology where necessary, and are providing summaries and policy briefings of our preliminary findings to inform public health action by working through our partnerships with our study advisory group, Public Health England, NHS and government scientific advisory panels., Competing Interests: Competing interests: AH serves on the UK New and Emerging Respiratory Virus Threats Advisory Group. AMJ was a governor of Wellcome Trust from 2011 to 2018 and is chair of the Committee for Strategic Coordination for Health of the Public Research., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.)

Background: There is little information on the prevalence of recreational drug use among UK heterosexual men and women, in particular on use of drugs associated with 'chemsex' within gay communities. The aim of this study was to examine among HIV-negative and HIV-positive heterosexual men and women in England: (i) the prevalence of recreational drug use (including use of drugs associated with chemsex), (ii) socio-economic/lifestyle correlates of drug use, and (iii) the association of drug use with sexual behavior measures and mental health symptoms., Methods: Data are from the AURAH study of HIV-negative individuals attending sexual health clinics across England (2013-2014) and the ASTRA study of HIV-positive individuals attending HIV outpatient clinics in England (2011-2012). Prevalence of recreational drug use (past three months) and associations are presented separately among the four sample groups: HIV-negative (N = 470) and HIV-positive (N = 373) heterosexual men and HIV-negative (N = 676) and HIV-positive (N = 637) women., Results: The age standardized prevalence of any drug use was 22.9%, 17.1%, 15.3%, and 7.1% in the four sample groups respectively. In all groups, cannabis was the drug most commonly used (range from 4.7% to 17.9%) followed by cocaine (1.6% to 8.5%). The prevalence of use of drugs associated with chemsex was very low among HIV-negative participants (1.0% heterosexual men, 0.2% women) and zero among HIV-positive men and women. In age-adjusted analysis, factors linked to drug use overall and/or to cannabis and cocaine use specifically in the four sample groups included Black/mixed Caribbean and white (vs. Black/mixed African) ethnicity, lower level of education , cigarette smoking, and higher risk alcohol consumption. Associations of recreational drug use with measures of condomless sex, depression, and anxiety were observed in the four groups, but were particularly strong/apparent among women., Conclusion: Providers need to be aware of cannabis and cocaine use and its potential link with sexual risk behavior and symptoms of depression and anxiety among heterosexual men and women attending sexual health and HIV clinics., Competing Interests: Declarations of Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier B.V.)

Introduction: Partner notification (PN) is a process aiming to identify, test and treat the sex partners of people (index patients) with sexually transmitted infections (STIs). Accelerated partner therapy (APT) is a PN method whereby healthcare professionals assess sex partners, by telephone consultation, before giving the index patient antibiotics and STI self-sampling kits to deliver to their sex partner(s). The Limiting Undetected Sexually Transmitted infections to RedUce Morbidity programme aims to determine the effectiveness of APT in heterosexual women and men with chlamydia and determine whether APT could affect Chlamydia trachomatis transmission at population level., Methods and Analysis: This protocol describes a cross-over cluster randomised controlled trial of APT, offered as an additional PN method, compared with standard PN. The trial is accompanied by an economic evaluation, transmission dynamic modelling and a qualitative process evaluation involving patients, partners and healthcare professionals. Clusters are 17 sexual health clinics in areas of England and Scotland with contrasting patient demographics. We will recruit 5440 heterosexual women and men with chlamydia, aged ≥16 years.The primary outcome is the proportion of index patients testing positive for C. trachomatis 12-16 weeks after the PN consultation. Secondary outcomes include: proportion of sex partners treated; cost effectiveness; model-predicted chlamydia prevalence; experiences of APT.The primary outcome analysis will be by intention-to-treat, fitting random effects logistic regression models that account for clustering of index patients within clinics and trial periods. The transmission dynamic model will be used to predict change in chlamydia prevalence following APT. The economic evaluation will use mathematical modelling outputs, taking a health service perspective. Qualitative data will be analysed using interpretative phenomenological analysis and framework analysis., Ethics and Dissemination: This protocol received ethical approval from London-Chelsea Research Ethics Committee (18/LO/0773). Findings will be published with open access licences., Trial Registration Number: ISRCTN15996256., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Objectives: Including questions about sexual health in the annual Health Survey for England (HSE) provides opportunities for regular measurement of key public health indicators, augmenting Britain's decennial National Survey of Sexual Attitudes and Lifestyles (Natsal). However, contextual and methodological differences may limit comparability of the findings. We examine the extent of these differences between HSE 2010 and Natsal-3 and investigate their impact on parameter estimates., Methods: Complex survey analyses of data from men and women in the 2010 HSE (n = 2,782 men and 3,588 women) and Natsal-3 undertaken 2010-2012 (n = 4,882 men and 6,869 women) aged 16-69y and resident in England, both using probability sampling, compared their characteristics, the amount of non-response to, and estimates from, sexual health questions. Both surveys used self-completion for the sexual behaviour questions but this was via computer-assisted self-interview (CASI) in Natsal-3 and a pen-and-paper questionnaire in HSE 2010., Results: The surveys achieved similar response rates, both around 60%, and demographic profiles largely consistent with the census, although HSE participants tended to be less educated, and reported worse general health, than Natsal-3 participants. Item non-response to the sexual health questions was typically higher in HSE 2010 (range: 9-18%) relative to Natsal-3 (all <5%). Prevalence estimates for sexual risk behaviours and STI-related indicators were generally slightly lower in HSE 2010 than Natsal-3., Conclusions: While a relatively high response to sexual health questions in HSE 2010 demonstrates the feasibility of asking such questions in a general health survey, differences with Natsal-3 do exist. These are likely due to the HSE's context as a general health survey and methodological limitations such as its current use of pen-and-paper questionnaires. Methodological developments to the HSE should be considered so that its data can be interpreted in combination with those from dedicated sexual health surveys, thus improving our ability to monitor trends in sexual health.

Rationale: A high proportion of influenza infections are asymptomatic. Animal and human challenge studies and observational studies suggest T cells protect against disease among those infected, but the impact of T-cell immunity at the population level is unknown., Objectives: To investigate whether naturally preexisting T-cell responses targeting highly conserved internal influenza proteins could provide cross-protective immunity against pandemic and seasonal influenza., Methods: We quantified influenza A(H3N2) virus-specific T cells in a population cohort during seasonal and pandemic periods between 2006 and 2010. Follow-up included paired serology, symptom reporting, and polymerase chain reaction (PCR) investigation of symptomatic cases., Measurements and Main Results: A total of 1,414 unvaccinated individuals had baseline T-cell measurements (1,703 participant observation sets). T-cell responses to A(H3N2) virus nucleoprotein (NP) dominated and strongly cross-reacted with A(H1N1)pdm09 NP (P < 0.001) in participants lacking antibody to A(H1N1)pdm09. Comparison of paired preseason and post-season sera (1,431 sets) showed 205 (14%) had evidence of infection based on fourfold influenza antibody titer rises. The presence of NP-specific T cells before exposure to virus correlated with less symptomatic, PCR-positive influenza A (overall adjusted odds ratio, 0.27; 95% confidence interval, 0.11-0.68; P = 0.005, during pandemic [P = 0.047] and seasonal [P = 0.049] periods). Protection was independent of baseline antibodies. Influenza-specific T-cell responses were detected in 43%, indicating a substantial population impact., Conclusions: Naturally occurring cross-protective T-cell immunity protects against symptomatic PCR-confirmed disease in those with evidence of infection and helps to explain why many infections do not cause symptoms. Vaccines stimulating T cells may provide important cross-protective immunity.

Introduction: Abdominal Aortic Aneurysm (AAA) involves dilatation of the abdominal aorta, with a natural history of expansion and eventual rupture. We have previously shown that AAA patients form denser clots with smaller pores, which are more resistant to fibrinolysis. The aim of this study was to use functional polymorphisms of the fibrinolytic system to identify how changes to proteins involved in fibrinolysis may play a role in the development of AAA., Methods: Caucasian subjects ≥ 55 years (602 AAA patients and 490 matched controls) were genotyped for four polymorphisms (α-2-antiplasmin α2AP Arg6Trp and Arg407Lys, Thrombin-activatable fibrinolysis inhibitor TAFI Thr325Ile and tissue plasminogen activator tPA 7351C→T). DNA was extracted from blood, and genotype identified using real time PCR. Fibrin clot structure was analysed by permeation and turbidity in a subset of patients and controls., Results: Genotypes across the study population were in Hardy-Weinberg Equilibrium. The two α2AP polymorphisms, Arg6Trp and Arg407Lys were in linkage disequilibrium (P<0.0001), and possession of a 407Lys allele negatively associated with AAA (odds ratio 0.833, CI95 0.7-0.991, P=0.040). The TAFI Thr325Ile and the tPA 7351C→T polymorphisms were not associated with AAA. The α2AP 407Lys allele was not associated with in-vitro fibrinolysis times in plasma from patients with AAA., Conclusion: Possession of the α2AP 407Lys allele was negatively associated with AAA, and thus changes in α2AP may affect aneurysm growth and development. These data indicate that the regulation of plasmin activity (through binding to α2AP), rather than plasmin generation (TAFI, tPA), may play a role in AAA., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: Assessment of the effect of influenza on populations, including risk of infection, illness if infected, illness severity, and consultation rates, is essential to inform future control and prevention. We aimed to compare the community burden and severity of seasonal and pandemic influenza across different age groups and study years and gain insight into the extent to which traditional surveillance underestimates this burden., Methods: Using preseason and postseason serology, weekly illness reporting, and RT-PCR identification of influenza from nasal swabs, we tracked the course of seasonal and pandemic influenza over five successive cohorts (England 2006-11; 5448 person-seasons' follow-up). We compared burden and severity of seasonal and pandemic strains. We weighted analyses to the age and regional structure of England to give nationally representative estimates. We compared symptom profiles over the first week of illness for different strains of PCR-confirmed influenza and non-influenza viruses using ordinal logistic regression with symptom severity grade as the outcome variable., Findings: Based on four-fold titre rises in strain-specific serology, on average influenza infected 18% (95% CI 16-22) of unvaccinated people each winter. Of those infected there were 69 respiratory illnesses per 100 person-influenza-seasons compared with 44 per 100 in those not infected with influenza. The age-adjusted attributable rate of illness if infected was 23 illnesses per 100 person-seasons (13-34), suggesting most influenza infections are asymptomatic. 25% (18-35) of all people with serologically confirmed infections had PCR-confirmed disease. 17% (10-26) of people with PCR-confirmed influenza had medically attended illness. These figures did not differ significantly when comparing pandemic with seasonal influenza. Of PCR-confirmed cases, people infected with the 2009 pandemic strain had markedly less severe symptoms than those infected with seasonal H3N2., Interpretation: Seasonal influenza and the 2009 pandemic strain were characterised by similar high rates of mainly asymptomatic infection with most symptomatic cases self-managing without medical consultation. In the community the 2009 pandemic strain caused milder symptoms than seasonal H3N2., Funding: Medical Research Council and the Wellcome Trust., (Copyright © 2014 Hayward et al. Open Access article distributed under the terms of CC BY. Published by .. All rights reserved.)

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-1pol 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.

Rates of hospital-acquired staphylococcal infection increased throughout the 1990s; however, information is limited on trends in community-onset staphylococcal disease in the United Kingdom. We used Hospital Episode Statistics to describe trends in hospital admissions for community-onset staphylococcal disease and national general practice data to describe trends in community prescribing for staphylococcal disease. Hospital admission rates for staphyloccocal septicemia, staphylococcal pneumonia, staphylococcal scalded-skin syndrome, and impetigo increased >5-fold. Admission rates increased 3-fold for abscesses and cellulitis and 1.5-fold for bone and joint infections. In primary care settings during 1991-2006, floxacillin prescriptions increased 1.8-fold and fusidic acidprescriptions 2.5-fold. The increases were not matched by increases in admission rates for control conditions. We identified a previously undescribed but major increase in pathogenic community-onset staphylococcal disease over the past 15 years. These trends are of concern given the international emergence of invasive community-onset staphylococcal infections.

Objectives: To quantify the contribution of patient delay, provider delay, and diversion between services to delayed access to genitourinary medicine (GUM) clinics. To describe the factors associated with delay, and their contribution to STI transmission., Methods: Cross-sectional survey of 3184 consecutive new patients attending four GUM clinics purposively selected from across England to represent different types of population. Patients completed a short written questionnaire that collected data on sociodemographics, access, and health-seeking behaviour. Questionnaires were then linked to routinely collected individual-level demographic and diagnostic data., Results: Patient delay is a median of 7 days, and does not vary by demographic or social characteristics, or by clinic. However, attendance at a walk-in appointment was associated with a marked reduction in patient delay and provider delay. Among symptomatics, 44.8% of men and 58.0% of women continued to have sex while awaiting treatment, with 7.0% reporting sex with >1 partner; 4.2% of symptomatic patients reported sex without using condoms with new partner(s) since their symptoms had begun. Approximately 25% of all patients had already sought or received care in general practice, and these patients experienced greater provider delay., Conclusions: Walk-in services are associated with a reduction in patient and provider delay, and should be available to all populations. Patients attending primary care require clear care pathways when referred on to GUM clinics. Health promotion should encourage symptomatic patients to seek care quickly, and to avoid sexual contact before treatment.

Purpose: To describe variations in age differences (ADs) between partners at first heterosexual intercourse and to examine associations between this AD, sociodemographic characteristics, and circumstances of first heterosexual intercourse, by gender., Methods: A total of 3277 men and 4734 women aged 25-44 years who reported ever having heterosexual intercourse in a probability survey of the British population to obtain an unbiased sample of ADs at first intercourse. Face-to-face interviews collected sociodemographic data and information on first intercourse. Gender-specific cumulative distributions of ADs categorized respondents reporting relatively younger first partners (below fifth percentile) and those reporting relatively older first partners (above 95th percentile)., Results: Relatively older first partners were six years older than men and 10 years older than women. Relatively younger first partners were three years younger than men and one year younger than women. Men and women with relatively older first partners were more likely to have just met their partner (odds ratios adjusted for sociodemographic characteristics [AOR] 1.8, 95% confidence interval [CI] 1.2-2.7, and 3.1, 95% CI 2.1-4.6, respectively); had a more willing first partner (AOR 2.1, 95% CI 1.2-3.8, and 1.6, 95% CI 1.2-2.2, respectively); not used condoms at first sex (AOR 1.9, 95% CI 1.2-3.0, and 1.5, 95% CI 1.1-2.0, respectively); and reported a non-autonomous reason for first sex (AOR 1.6, 95% CI 1.1-2.4, women only). Men with relatively younger first partners were more likely to regret the timing of the first occasion (AOR 2.1, 95% CI 1.0-4.5)., Conclusions: First partnerships involving relatively older or younger partners are associated with adverse circumstances of first intercourse. Condoms and other reliable contraception are less likely to be used, and age differences may reflect unequal power relations. Promoting effective communication and negotiation skills may be particularly important for those with relatively older or younger first partners.