Risk of hospitalisation or death in households with a case of COVID-19 in England: an analysis using the HOSTED data set.

OBJECTIVE: To determine whether household contacts of confirmed cases of COVID-19 have an increased risk of hospitalisation or death. METHODS: We used the HOSTED data set of index cases of COVID-19 in England between June and November 2020, linked to Secondary Uses Service data on hospital episodes and Office for National Statistics' mortality data. Multivariable logistic regression models of the odds of household contacts being hospitalised or dying within six weeks of an index case, adjusted for case type, age, sex and calendar month were calculated. Excess risk was determined by comparing the first six weeks after the index case with 6-12 weeks after the index case in a survival analysis framework. RESULTS: Index cases were more likely to be hospitalised or die than either secondary cases or non-cases, having adjusted for age and sex. There was an increased risk of hospitalisation for non-cases (adjusted hazard ratio (aHR) 1.10; 95% confidence interval (CI) 1.04, 1.16) and of death (aHR 1.57; 95% CI 1.14, 2.16) in the first six weeks after an index case, compared to 6-12 weeks after. CONCLUSION: Risks of hospitalisation and mortality are predictably higher in cases compared to non-cases. The short-term increase in risks for non-case contacts following diagnosis of the index case may suggest incomplete case ascertainment among contacts, although this was relatively small.

Who is coming back for more chlamydia testing within non-specialist health services and where do they go? England, 2013-2016.

OBJECTIVES: To investigate patient demographics and venue type preferences within community settings associated with re-attendance for chlamydia testing. STUDY DESIGN: Data used for this analysis were obtained from the English National Chlamydia Screening Programme (NCSP) which focuses on prevention, control and treatment of chlamydia in sexually active under-25 year olds. A greater understanding of how young adults attend services helps to inform commissioners regarding where to focus resources within community settings. METHODS: Data from the Chlamydia surveillance system (CTAD) were used to count patient attendances at non-specialist sexual health services (SHSs) among 15-24-year-olds and monitor re-attendance for chlamydia testing within and between community services between 6 and 18 months of their first visit. RESULTS: From January 2013 to December 2016, 866,847 young people underwent 1,041,245 tests for chlamydia. Re-attendance for chlamydia testing was 20.1% (174,398/866,847). Re-attendance rate was 28.5% after a positive test and 19.5% after a negative test. For re-attenders, 64.2% used the same venue type for both visits. General practice (GP) and sexual and reproductive health services (SRH) were the most commonly re-attended services (31.0% and 30.6% respectively). CONCLUSIONS: Only one in five re-attended for chlamydia testing. Re-attendance was associated with having a positive result, accessibility and convenience. Patients are likely to return for testing to services they know. This should be considered by commissioners implementing new re-attendance guidance based on the NCSP.

Exploring why a complex intervention piloted in general practices did not result in an increase in chlamydia screening and diagnosis: a qualitative evaluation using the fidelity of implementation model.

BACKGROUND: Chlamydia trachomatis (chlamydia) is the most commonly diagnosed sexually transmitted infection (STI) in England; approximately 70% of diagnoses are in sexually active young adults aged under 25. To facilitate opportunistic chlamydia screening in general practice, a complex intervention, based on a previously successful Chlamydia Intervention Randomised Trial (CIRT), was piloted in England. The modified intervention (3Cs and HIV) aimed to encourage general practice staff to routinely offer chlamydia testing to all 15-24 year olds regardless of the type of consultation. However, when the 3Cs (chlamydia screening, signposting to contraceptive services, free condoms) and HIV was offered to a large number of general practitioner (GP) surgeries across England, chlamydia screening was not significantly increased. This qualitative evaluation addresses the following aims: a) Explore why the modified intervention did not increase screening across all general practices. b) Suggest recommendations for future intervention implementation. METHODS: Phone interviews were carried out with 26 practice staff, at least 5 months after their initial educational workshop, exploring their opinions on the workshop and intervention implementation in the real world setting. Interview transcripts were thematically analysed and further examined using the fidelity of implementation model. RESULTS: Participants who attended had a positive attitude towards the workshops, but attendee numbers were low. Often, the intervention content, as detailed in the educational workshops, was not adhered to: practice staff were unaware of any on-going trainer support; computer prompts were only added to the female contraception template; patients were not encouraged to complete the test immediately; complete chlamydia kits were not always readily available to the clinicians; and videos and posters were not utilised. Staff reported that financial incentives, themselves, were not a motivator; competing priorities and time were identified as major barriers. CONCLUSION: Not adhering to the exact intervention model may explain the lack of significant increases in chlamydia screening. To increase fidelity of implementation outside of Randomised Controlled Trial (RCT) conditions, and consequently, improve likelihood of increased screening, future public health interventions in general practices need to have: more specific action planning within the educational workshop; computer prompts added to systems and used; all staff attending the workshop; and on-going practice staff support with feedback of progress on screening and diagnosis rates fed back to all staff.

Supporting general practices to provide sexual and reproductive health services: protocol for the 3Cs & HIV programme.

OBJECTIVES: Sexually transmitted infections, HIV and unplanned pregnancies continue to be a major public health problem in England, especially in young adults. Strengthening the provision of free condoms, HIV testing, chlamydia screening and contraception within primary care will contribute to reducing poor sexual and reproductive health outcomes. Recent research demonstrated the benefit for general practices of educational support visits based on behaviour change theory. Public Health England (PHE) has piloted an educational training programme to improve the delivery of sexual health services and HIV testing within general practice. STUDY DESIGN & METHODS: The 3Cs & HIV programme used practice based workshops to improve staffs' awareness and skills in order to increase opportunistic offers of chlamydia testing, provision of contraceptive service information and free condoms (the '3Cs') to 15-24 year olds and HIV testing according to national guidelines. The programme was based on the theory of planned behaviour and has been implemented using a stepped wedge design. Process evaluation, testing and diagnosis data, plus qualitative interviews were all used in the evaluation. The primary outcome measures were chlamydia testing and diagnosis rates. Secondary outcome measures were HIV testing and diagnoses rates within each practice and rates of consultations where long acting reversible contraceptives had been discussed. CONCLUSION: A key strength of the 3Cs & HIV programme has been the evidence base underpinning the development of the resources and the formal process evaluation of its implementation. The programme was designed to encourage sustainable relationships between general practice staff and local sexual health services as well as the knowledge, awareness and behaviours cultivated during the programme.

Intravenous drug use: not a barrier to achieving a sustained virological response in HCV infection.

Hepatitis C virus (HCV) is commonly transmitted by intravenous drug use (IDU) but drug users are under represented in many treatment cohorts, this is because of the assumption of lowered treatment success. We assessed HCV treatment outcomes in active intravenous drug users and patients on opiate substitution therapy. The Tayside HCV treatment database was retrospectively analysed for consecutively treated patients based on risk factor for acquisition of HCV. Primary end point was sustained virological response (SVR). Two hundred and ninety-one consecutively treated patients were assessed. The overall SVR rate was 55.3%. The SVR rates by risk factor were; Non-IDU 61.4%, Ex-IDU 54.8% and Active IDU 47.1% (P = n/s). In the groups G1 patients SVR was; Non-IDU 52.7%, Ex-IDU 30.7% and active IDU 35.4% (P = n/s). In the non-G1 patients: non-IDU 65.1%, Ex-IDU 76.7% and active IDU 53.5%. Ex-IDU had a significantly better SVR than active IDU, other differences were not significant. Our results demonstrate that SVR rates in the active drug users and those on opiate substitution therapy can be achieved which are comparable with non-IDU infected individuals. Intravenous drug use in those engaged with treatment services should not be seen as a barrier to treatment of HCV.

Public health on-call in Scotland: how much experience is sufficient?

OBJECTIVES: To quantify the out-of-hours experience obtained by public health trainees in Scotland and to assess whether this is sufficient to meet the Faculty of Public Health guidelines. STUDY DESIGN: Prospective survey. METHODS: All public health trainees in Scotland were invited to participate in a prospective survey of out-of-hours experience. Data were collected from March 2009 to March 2010. The variation in the experience between trainees was compared according to the size, urban/rural mix, and deprivation of the population for which they were responsible. The variation in the experiences gained were then compared to the requirements of the Faculty of Public Health. RESULTS: 18 trainees participated from 6 areas, collecting data on 391 shifts and a total of 276 calls. For every 50 shifts the median number of notifications of probable meningococcus was 3.7 and the median number of chemical incidents and Escherichia coli O157 notifications was 0.0. This variation is difficult to interpret because some trainees collected data for only a short period. The variation between trainees was not significantly related to population size, deprivation or rurality. Pooling the data from all trainees, there was a mean of 2.9 probable meningococcus notifications, 2.4 E coli O157 calls, and 0.3 chemical incident calls per 50 shifts. CONCLUSIONS: There is a large and unpredictable degree of variation in the on-call experience of Scottish trainees. The minimum recommended number of on-call shifts may not be adequate to ensure a high proportion of trainees are prepared for unsupervised on-call.

World Congress of Epidemiology 2011: themes and highlights.

Modern-day epidemiologists are confronted with huge changes, such as the rise in the global population due to reduced mortality, migration within and across countries, massive shifts in economic standing and lifestyles, and environmental degradation. With over 1000 posters, more than 100 oral presentations, 16 workshops, four lunchtime symposia, many exhibitions and immeasurable discussions, the task of capturing all highlights of the International Epidemiology Association (IEA) World Congress of Epidemiology 2011 is impossible, but this article has provided a sample. Many presenters showed that the challenges facing global health are complex, changing and in demand of measurement, and they demonstrated the central role of epidemiology. The cutting-edge methodologies theme promised the emergence of a more transparent, better balanced, but also more critical approach to dealing with bias. Preceding the United Nations high-level meeting on non-communicable diseases (New York, 19th-20th September 2011), the Congress's chronic diseases stream was especially timely. The neglected conditions theme illustrated inspiring work battling against apathy, inertia and ignorance; perhaps the special challenge of the 'neglected conditions epidemiologist'. Translating epidemiology's insights into effective policies and programmes to prevent diseases or reduce their impact is not easy. Speakers highlighted the common failure of epidemiologists to contribute actively to improving the health of the populations they serve, especially the poor and disadvantaged, but also provided many examples where they had done so. The 'other' theme ensured that important studies were not lost from the programme just because they did not fit easily into the specific themes. The studies focused on identified risk factors throughout the life course. A variety of methods were used to identify factors that altered the rate of birth, disease and death. Ongoing epidemiology is not only broad but is also deep, and ever more so as collaborative pooling of expertise, data, populations and ideas has emerged, accelerated by modern-day communication technologies. Epidemiology, and epidemiologists, seem poised for tomorrow's world.

HOSTED-England's Household Transmission Evaluation Dataset: preliminary findings from a novel passive surveillance system of COVID-19.

BACKGROUND: Household transmission of SARS-CoV-2 is an important component of the community spread of the pandemic. Little is known about the factors associated with household transmission, at the level of the case, contact or household, or how these have varied over the course of the pandemic. METHODS: The Household Transmission Evaluation Dataset (HOSTED) is a passive surveillance system linking laboratory-confirmed COVID-19 cases to individuals living in the same household in England. We explored the risk of household transmission according to: age of case and contact, sex, region, deprivation, month and household composition between April and September 2020, building a multivariate model. RESULTS: In the period studied, on average, 5.5% of household contacts in England were diagnosed as cases. Household transmission was most common between adult cases and contacts of a similar age. There was some evidence of lower transmission rates to under-16s [adjusted odds ratios (aOR) 0.70, 95% confidence interval (CI) 0.66-0.74). There were clear regional differences, with higher rates of household transmission in the north of England and the Midlands. Less deprived areas had a lower risk of household transmission. After controlling for region, there was no effect of deprivation, but houses of multiple occupancy had lower rates of household transmission [aOR 0.74 (0.66-0.83)]. CONCLUSIONS: Children are less likely to acquire SARS-CoV-2 via household transmission, and consequently there was no difference in the risk of transmission in households with children. Households in which cases could isolate effectively, such as houses of multiple occupancy, had lower rates of household transmission. Policies to support the effective isolation of cases from their household contacts could lower the level of household transmission.

Diagnostic accuracy of a prototype rapid chlamydia and gonorrhoea recombinase polymerase amplification assay: a multicentre cross-sectional preclinical evaluation.

OBJECTIVES: Rapid and accurate sexually transmitted infection diagnosis can reduce onward transmission and improve treatment efficacy. We evaluated the accuracy of a 15-minute run-time recombinase polymerase amplification-based prototype point-of-care test (TwistDx) for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). METHODS: Prospective, multicentre study of symptomatic and asymptomatic patients attending three English sexual health clinics. Research samples provided were additional self-collected vulvovaginal swab (SCVS) (female participants) and first-catch urine (FCU) aliquot (female and male participants). Samples were processed blind to the comparator (routine clinic CT/NG nucleic acid amplification test (NAAT)) results. Discrepancies were resolved using Cepheid CT/NG GeneXpert. RESULTS: Both recombinase polymerase amplification and routine clinic NAAT results were available for 392 male and 395 female participants. CT positivity was 8.9% (35/392) (male FCU), 7.3% (29/395) (female FCU) and 7.1% (28/395) (SCVS). Corresponding NG positivity was 3.1% (12/392), 0.8% (3/395) and 0.8% (3/395). Specificity and positive predictive values were 100% for all sample types and both organisms, except male CT FCU (99.7% specificity (95% confidence interval (CI) 98.4-100.0; 356/357), 97.1% positive predictive value (95% CI 84.7-99.9; 33/34)). For CT, sensitivity was ≥94.3% for FCU and SCVS. CT sensitivity for female FCU was higher (100%; 95% CI, 88.1-100; 29/29) than for SCVS (96.4%; 95% CI, 81.7-99.9; 27/28). NG sensitivity and negative predictive values were 100% in FCU (male and female). CONCLUSIONS: This prototype test has excellent performance characteristics, comparable to currently used NAATs, and fulfils several World Health Organization ASSURED criteria. Its rapidity without loss of performance suggests that once further developed and commercialized, this test could positively affect clinical practice and public health.

A 30-Min Nucleic Acid Amplification Point-of-Care Test for Genital Chlamydia trachomatis Infection in Women: A Prospective, Multi-center Study of Diagnostic Accuracy.

BACKGROUND: Rapid Point-Of-Care Tests for Chlamydia trachomatis (CT) may reduce onward transmission and reproductive sexual health (RSH) sequelae by reducing turnaround times between diagnosis and treatment. The io® single module system (Atlas Genetics Ltd.) runs clinical samples through a nucleic acid amplification test (NAAT)-based CT cartridge, delivering results in 30min. METHODS: Prospective diagnostic accuracy study of the io® CT-assay in four UK Genito-Urinary Medicine (GUM)/RSH clinics on additional-to-routine self-collected vulvovaginal swabs. Samples were tested "fresh" within 10days of collection, or "frozen" at -80°C for later testing. Participant characteristics were collected to assess risk factors associated with CT infection. RESULTS: CT prevalence was 7.2% (51/709) overall. Sensitivity, specificity, positive and negative predictive values of the io® CT assay were, respectively, 96.1% (95% Confidence Interval (CI): 86.5-99.5), 97.7% (95%CI: 96.3-98.7), 76.6% (95%CI: 64.3-86.2) and 99.7% (95%CI: 98.9-100). The only risk factor associated with CT infection was being a sexual contact of an individual with CT. CONCLUSIONS: The io® CT-assay is a 30-min, fully automated, high-performing NAAT currently CE-marked for CT diagnosis in women, making it a highly promising diagnostic to enable specific treatment, initiation of partner notification and appropriately intensive health promotion at the point of care.

Genetic epidemiology.

The field of genetic epidemiology has advanced considerably over the past decade. The falling costs of genome-wide association studies have allowed the identification of many common genetic variants associated with risk of illness. This has advanced the understanding of disease pathogenesis but has not led to widespread changes in care. As these studies have become more common, a framework for reporting findings in the literature has been developed to ensure clinicians can accurately interpret the research. In future, whole genome genetic sequencing will likely lead to the identification of rarer variants more strongly associated with illness. Currently large resources for research, such as the UK Biobank project, are being developed which will allow detailed exploration of not only genes but the way their actions are controlled.