Duration of Protection against Mild and Severe Disease by Covid-19 Vaccines.

BACKGROUND: Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (Covid-19), have been used since December 2020 in the United Kingdom. Real-world data have shown the vaccines to be highly effective against Covid-19 and related severe disease and death. Vaccine effectiveness may wane over time since the receipt of the second dose of the ChAdOx1-S (ChAdOx1 nCoV-19) and BNT162b2 vaccines. METHODS: We used a test-negative case-control design to estimate vaccine effectiveness against symptomatic Covid-19 and related hospitalization and death in England. Effectiveness of the ChAdOx1-S and BNT162b2 vaccines was assessed according to participant age and status with regard to coexisting conditions and over time since receipt of the second vaccine dose to investigate waning of effectiveness separately for the B.1.1.7 (alpha) and B.1.617.2 (delta) variants. RESULTS: Vaccine effectiveness against symptomatic Covid-19 with the delta variant peaked in the early weeks after receipt of the second dose and then decreased by 20 weeks to 44.3% (95% confidence interval [CI], 43.2 to 45.4) with the ChAdOx1-S vaccine and to 66.3% (95% CI, 65.7 to 66.9) with the BNT162b2 vaccine. Waning of vaccine effectiveness was greater in persons 65 years of age or older than in those 40 to 64 years of age. At 20 weeks or more after vaccination, vaccine effectiveness decreased less against both hospitalization, to 80.0% (95% CI, 76.8 to 82.7) with the ChAdOx1-S vaccine and 91.7% (95% CI, 90.2 to 93.0) with the BNT162b2 vaccine, and death, to 84.8% (95% CI, 76.2 to 90.3) and 91.9% (95% CI, 88.5 to 94.3), respectively. Greater waning in vaccine effectiveness against hospitalization was observed in persons 65 years of age or older in a clinically extremely vulnerable group and in persons 40 to 64 years of age with underlying medical conditions than in healthy adults. CONCLUSIONS: We observed limited waning in vaccine effectiveness against Covid-19-related hospitalization and death at 20 weeks or more after vaccination with two doses of the ChAdOx1-S or BNT162b2 vaccine. Waning was greater in older adults and in those in a clinical risk group.

Meta-analysis of the human upper respiratory tract microbiome reveals robust taxonomic associations with health and disease.

BACKGROUND: The human upper respiratory tract (URT) microbiome, like the gut microbiome, varies across individuals and between health and disease states. However, study-to-study heterogeneity in reported case-control results has made the identification of consistent and generalizable URT-disease associations difficult. RESULTS: In order to address this issue, we assembled 26 independent 16S rRNA gene amplicon sequencing data sets from case-control URT studies, with approximately 2-3 studies per respiratory condition and ten distinct conditions covering common chronic and acute respiratory diseases. We leveraged the healthy control data across studies to investigate URT associations with age, sex, and geographic location, in order to isolate these associations from health and disease states. CONCLUSIONS: We found several robust genus-level associations, across multiple independent studies, with either health or disease status. We identified disease associations specific to a particular respiratory condition and associations general to all conditions. Ultimately, we reveal robust associations between the URT microbiome, health, and disease, which hold across multiple studies and can help guide follow-up work on potential URT microbiome diagnostics and therapeutics.

Identification of two novel subtypes of hepatitis C virus genotype 8 and a potential new genotype successfully treated with direct acting antivirals.

BACKGROUND: Hepatitis C virus (HCV) has a high genetic diversity and is classified into 8 genotypes and over 90 subtypes with some endemic to specific world regions. This could compromise direct-acting antiviral (DAA) efficacy and global HCV elimination. METHODS: We characterised HCV subtypes 'rare' to the UK (non-1a/1b/2b/3a/4d) by whole genome sequencing via a national surveillance programme. Genetic analyses to determine the genotype of samples with unresolved genotypes were undertaken by comparison with ICTV HCV reference sequences. RESULTS: Two HCV variants were characterised as being closely related to the recently identified genotype 8 (GT8), with >85% pairwise genetic distance similarity to GT8 sequences and within the typical inter-subtype genetic distance range. The individuals infected by the variants were UK residents originally from Pakistan and India. In contrast, a third variant was only confidently identified to be more similar to GT6 compared to other genotypes across 6% of the genome and was isolated from a UK resident originally from Guyana. All three were cured with pangenotypic DAAs (Sofosbuvir + Velpatasvir or Glecaprevir + Pibrentasvir) despite the presence of resistance polymorphisms in NS3 (80 K/168E), NS5A (28 V/30S/62L/92S/93S) and NS5B (159F). CONCLUSIONS: This study expands our knowledge of HCV diversity by identifying two new GT8 subtypes and potentially a new genotype.

Effects of BNT162b2 Messenger RNA Vaccine and ChAdOx1 Adenovirus Vector Vaccine on Deaths From COVID-19 in Adults Aged ≥70 Years.

We estimated the risk of death from coronavirus disease 2019 in vaccinated compared with unvaccinated patients. The risk of death was reduced 44% after 1 dose of the Pfizer-BioNTech BNT162b2 vaccine, 55% after 1 dose of the Oxford-Astrazeneca ChAdOx1 vaccine, and 69% after 2 doses of the BNT162b2 vaccine. This is above the protection provided against infection.

Mental health in the COVID-19 pandemic: A longitudinal analysis of the CLoCk cohort study.

BACKGROUND: Little is known about the long-term mental health consequences of the pandemic in children and young people (CYP), despite extremely high levels of exposure to the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus and the disruption to schooling and leisure activities due to the resultant restrictions. There are mixed findings from systematic reviews of how the pandemic affected CYP's mental health, which may be due to heterogeneous methods and poor quality studies. Most, but not all, suggest deterioration in mental health but population level studies may obscure the differing experiences of subgroups. The study questions are: (i) are there subgroups of CYP with distinct mental health profiles over the course of the second year of the Coronavirus Disease 2019 (COVID-19) pandemic (between April 2021 and May 2022); and (ii) do vulnerability factors influence CYP's mental health trajectories. METHODS AND FINDINGS: A matched longitudinal cohort study of non-hospitalised test-positive and test-negative 11- to 17-year-old CYP in England were recruited from the UK Health Security Agency having undergone PCR testing for COVID-19. They completed the Strengths and Difficulties Questionnaire (SDQ) at least twice over a 12-month follow-up period. Overall, 8,518 of 17,918 (47.5%) CYP who returned their first SDQ at 3 or 6 months post-testing were included in the analytical sample. Associations between age, sex, ethnicity, socioeconomic status (SES), and an educational health and care plan (EHCP, indicating special educational needs) on SDQ score trajectories were examined separately, after adjusting for PCR test result. Findings from multilevel mixed-effects linear regression model showed that on average mental health symptoms as measured by the total SDQ score increased over time (B = 0.11 (per month), 95% CI = 0.09 to 0.12, p < 0.001) although this increase was small and not clinically significant. However, associations with time varied by age, such that older participants reported greater deterioration in mental health over time (B = 0.12 (per month), 95% CI = 0.10 to 0.14 for 15 to 17y; 0.08 (95% CI = 0.06 to 0.10) for 11 to 14y; pinteraction = 0.002) and by sex, with greater deterioration in girls. Children with an EHCP experienced less deterioration in their mental health compared to those without an EHCP. There was no evidence of differences in rate of change in total SDQ by ethnicity, SES, or physical health. Those with worse prior mental health did not appear to be disproportionately negatively affected over time. There are several limitations of the methodology including relatively low response rates in CLoCk and potential for recall bias. CONCLUSIONS: Overall, there was a statistically but not clinically significant decline in mental health during the pandemic. Sex, age, and EHCP status were important vulnerability factors that were associated with the rate of mental health decline, whereas ethnicity, SES, and prior poor physical health were not. The research highlights individual factors that could identify groups of CYP vulnerable to worsening mental health.

Effectiveness of Covid-19 Vaccines against the B.1.617.2 (Delta) Variant.

BACKGROUND: The B.1.617.2 (delta) variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (Covid-19), has contributed to a surge in cases in India and has now been detected across the globe, including a notable increase in cases in the United Kingdom. The effectiveness of the BNT162b2 and ChAdOx1 nCoV-19 vaccines against this variant has been unclear. METHODS: We used a test-negative case-control design to estimate the effectiveness of vaccination against symptomatic disease caused by the delta variant or the predominant strain (B.1.1.7, or alpha variant) over the period that the delta variant began circulating. Variants were identified with the use of sequencing and on the basis of the spike (S) gene status. Data on all symptomatic sequenced cases of Covid-19 in England were used to estimate the proportion of cases with either variant according to the patients' vaccination status. RESULTS: Effectiveness after one dose of vaccine (BNT162b2 or ChAdOx1 nCoV-19) was notably lower among persons with the delta variant (30.7%; 95% confidence interval [CI], 25.2 to 35.7) than among those with the alpha variant (48.7%; 95% CI, 45.5 to 51.7); the results were similar for both vaccines. With the BNT162b2 vaccine, the effectiveness of two doses was 93.7% (95% CI, 91.6 to 95.3) among persons with the alpha variant and 88.0% (95% CI, 85.3 to 90.1) among those with the delta variant. With the ChAdOx1 nCoV-19 vaccine, the effectiveness of two doses was 74.5% (95% CI, 68.4 to 79.4) among persons with the alpha variant and 67.0% (95% CI, 61.3 to 71.8) among those with the delta variant. CONCLUSIONS: Only modest differences in vaccine effectiveness were noted with the delta variant as compared with the alpha variant after the receipt of two vaccine doses. Absolute differences in vaccine effectiveness were more marked after the receipt of the first dose. This finding would support efforts to maximize vaccine uptake with two doses among vulnerable populations. (Funded by Public Health England.).

Identifying missed opportunities for hepatitis C virus antenatal testing and diagnosis in England.

New case-finding opportunities are needed to achieve hepatitis C virus (HCV) elimination in England by the year 2030. HCV antenatal testing is not offered universally in England but is recommended for women with risk factors for HCV (e.g. injecting drug use, being born in a high-prevalence country). The aim of this analysis was to investigate the missed opportunities for HCV antenatal testing among women who had given birth and were subsequently diagnosed with HCV at some time after childbirth. By linking data on live births (2010-2020) to laboratory reports of HCV diagnoses (1995-2021), we identified all women who were diagnosed with HCV after the date of their first childbirth. This group was considered to potentially have experienced a missed opportunity for HCV antenatal testing; HCV-RNA testing and treatment outcomes were also obtained for these women. Of the 32,295 women who gave birth between 2010 and 2020 with a linked diagnosis of HCV (median age: 34 years, 72.1% UK-born), over half (n = 17,123) were diagnosed after childbirth. In multivariable analyses, the odds of being diagnosed with HCV after childbirth were higher in those of Asian Bangladeshi, Black African or Chinese ethnicity and among those born in Africa. Over four-fifths (3510/4260) of those eligible for treatment were linked to treatment, 30.7% (747/2435) of whom had a liver scarring level of at least moderate and 9.4% (228/2435) had cirrhosis. Given the potential opportunity to identify cases of HCV with targeted case-finding through antenatal services, universal opt-out testing should be considered in these settings.

Estimating Prevalence and Number of People With Chronic Hepatitis B: A Multiplier Method Based on Public Health Surveillance Data in UK (2015-2021).

Estimates of chronic hepatitis B virus (HBV) prevalence and critically the amount of infection that is undiagnosed or unlinked to care are uncertain-even in countries like UK where vertical transmission and overall prevalence are very low. In the absence of country of birth data, we aim to estimate HBV prevalence through combining public health surveillance data on antenatally screened women by ethnic group and multipliers generated from non-antenatally screened populations by ethnic group with English population denominators. Of 714,287 women aged 16-49 years with ethnic group data tested as part of antenatal care between 2015 and 2021, 4174 (0.6%) were HBsAg-positive; 94% in people of ethnic groups other than White British. Of 1,447,467 people tested for HBsAg with ethnic group data from other testing sources (primary and secondary care excluding occupational health and renal services), 27,628 (1.9%) were HBsAg-positive; 87% in people of ethnic groups other than White British. We estimate that the overall number and prevalence of people with chronic hepatitis B in England is 268,767 (95% CI: 227,896-314,044) and 0.58% (95% CI: 0.50-0.68). Approximately two-thirds were male, one-third female, and 68% were aged under 50. We estimate that over 83% of HBV infections are in people of ethnic groups other than White British, with 23% in people from Black ethnic groups, 21% from other White ethnic groups and 19% in Asian ethnic groups. These estimates are the first step towards establishing whether England can meet World Health Organisation targets to eliminate HBV as a public health problem-using methods that can also be used by other countries.

Seroprevalence of immunity to hepatitis A and hepatitis B among gay, bisexual and other men who have sex with men (GBMSM) attending sexual health clinics in London and Leeds, England, 2017-2018.

OBJECTIVES: Although hepatitis A virus (HAV) and hepatitis B virus (HBV) immunisation is recommended in the UK for gay, bisexual and other men who have sex with men (GBMSM), data on immunisation coverage are limited. We aimed to determine the seroprevalence of HAV and HBV immunity among a sample of GBMSM attending sexual health services (SHS) in England. METHODS: Residual serum samples from HIV/syphilis testing for adult GBMSM attending eight SHS in London and one in Leeds were tested for markers of HAV immunity (HAV IgG) and HBV immunity (anti-HBs) using an unlinked anonymous approach. We estimated seroprevalence of HAV and HBV immunity overall and stratified by individuals' characteristics, which we obtained from the Genitourinary Medicine Clinic Activity Dataset Sexually Transmitted Infection (STI) Surveillance System. We used logistic regression to calculate crude and adjusted ORs between seropositivity and demographic and clinical characteristics. RESULTS: Seroprevalence of immunity to HAV (74.5% of 2577) and HBV (77.1% of 2551) was high. In adjusted analysis, HAV IgG seroprevalence varied by clinic and WHO region of birth (global p<0.001 for each), increased with older age (ORs of 1.50 (95% CI 1.18 to 1.86), 2.91 (2.17 to 3.90) and 3.40 (2.44 to 4.75) for ages 26-35, 36-45 and >46 vs 18-25 years (global p<0.001), was higher in those with an STI in the past year (1.58 (1.25 to 2.00); p<0.001) and those who were living with HIV (1.82 (1.25 to 2.64); p<0.001). Anti-HBs seroprevalence varied by clinic (global p<0.001), increased with older age (global p<0.001) and was higher in those with an STI in the past year (1.61 (1.27 to 2.05); p<0.001). CONCLUSION: Our findings provide a baseline seroprevalence from which to monitor serial levels of immunity to HBV and HAV in GBMSM accessing SHS. Levels of immunity for both viruses are high, noting samples were taken after recent widespread outbreaks and vaccination campaigns. High vaccine coverage in all GBMSM should be maintained to prevent further outbreaks.

Prevalence and co-occurrence of cognitive impairment in children and young people up to 12-months post infection with SARS-CoV-2 (Omicron variant).

BACKGROUND: Cognitive impairment is often reported after SARS-CoV-2 infection, yet evidence gaps remain. We aimed to (i) report the prevalence and characteristics of children and young people (CYP) reporting "brain fog" (i.e., cognitive impairment) 12-months post PCR-proven SARS-CoV-2 infection and determine whether differences by infection status exist and (ii) explore the prevalence of CYP experiencing cognitive impairment over a 12-month period post-infection and investigate the relationship between cognitive impairment and poor mental health and well-being, mental fatigue and sleep problems. METHODS: The Omicron CLoCk sub-study, set up in January 2022, collected data on first-time PCR-test-positive and PCR-proven reinfected CYP at time of testing and at 3-, 6- and 12-months post-testing. We describe the prevalence of cognitive impairment at 12-months, indicating when it was first reported. We characterise CYP experiencing cognitive impairment and use chi-squared tests to determine whether cognitive impairment prevalence varied by infection status. We explore the relationship between cognitive impairment and poor mental health and well-being, mental fatigue and trouble sleeping using validated scales. We examine associations at 3-, 6- and 12-months post-testing by infection status using Mann-Whitney U and chi-square tests. RESULTS: At 12-months post-testing, 7.0 % (24/345) of first-positives and 7.5 % (27/360) of reinfected CYP experienced cognitive impairment with no difference between infection-status groups (p = 0.78). The majority of these CYP experienced cognitive impairment for the first time at either time of testing or 3-months post-test (no difference between the infection-status groups; p = 0.60). 70.8 % of first-positives experiencing cognitive impairment at 12-months, were 15-to-17-years-old as were 33.3 % of reinfected CYP experiencing cognitive impairment (p < 0.01). Consistently at all time points post-testing, CYP experiencing cognitive impairment were more likely to score higher on all Strengths and Difficulties Questionnaire subscales, higher on the Chalder Fatigue sub-scale for mental fatigue, lower on the Short Warwick-Edinburgh Mental Wellbeing Scale and report more trouble sleeping. CONCLUSIONS: CYP have a fluctuating experience of cognitive impairment by 12-months post SARS-CoV-2-infection. Cognitive impairment is consistently correlated with poorer sleep, behavioural and emotional functioning over a 12-month period. Clinicians should be aware of cognitive impairment post-infection and its co-occurring nature with poorer sleep, behavioural and mental health symptoms.

Developing survey weights to ensure representativeness in a national, matched cohort study: results from the children and young people with Long Covid (CLoCk) study.

BACKGROUND: Findings from studies assessing Long Covid in children and young people (CYP) need to be assessed in light of their methodological limitations. For example, if non-response and/or attrition over time systematically differ by sub-groups of CYP, findings could be biased and any generalisation limited. The present study aimed to (i) construct survey weights for the Children and young people with Long Covid (CLoCk) study, and (ii) apply them to published CLoCk findings showing the prevalence of shortness of breath and tiredness increased over time from baseline to 12-months post-baseline in both SARS-CoV-2 Positive and Negative CYP. METHODS: Logistic regression models were fitted to compute the probability of (i) Responding given envisioned to take part, (ii) Responding timely given responded, and (iii) (Re)infection given timely response. Response, timely response and (re)infection weights were generated as the reciprocal of the corresponding probability, with an overall 'envisioned population' survey weight derived as the product of these weights. Survey weights were trimmed, and an interactive tool developed to re-calibrate target population survey weights to the general population using data from the 2021 UK Census. RESULTS: Flexible survey weights for the CLoCk study were successfully developed. In the illustrative example, re-weighted results (when accounting for selection in response, attrition, and (re)infection) were consistent with published findings. CONCLUSIONS: Flexible survey weights to address potential bias and selection issues were created for and used in the CLoCk study. Previously reported prospective findings from CLoCk are generalisable to the wider population of CYP in England. This study highlights the importance of considering selection into a sample and attrition over time when considering generalisability of findings.

Histopathological findings from the investigation of paediatric acute hepatitis of unknown aetiology, United Kingdom 2022.

In 2022, there were global reports of increased numbers of acute hepatitis not explained by hepatitis A-E virus infection in children. This manuscript summarises histopathology results from 20 patients in the United Kingdom who underwent liver transplant or had a liver biopsy as part of aetiological investigations. All available histopathological samples were reviewed centrally as part of the outbreak investigation. A working group comprised of infection specialists, hepatologists and histopathologists met virtually to review the cases, presentation, investigations and histopathology. All 20 liver samples had evidence of inflammation without significant interface activity, and submassive confluent pan-lobular or multilobular hepatocellular necrosis. Overall, the predominant histopathological findings were of acute nonspecific hepatitis with submassive hepatic necrosis and central vein perivenulitis and endothelitis. Histopathological findings were a poor indicator of aetiology.

Results from a retrospective case finding and re-engagement exercise for people previously diagnosed with hepatitis C virus to increase uptake of directly acting antiviral treatment.

BACKGROUND: Direct acting antivirals (DAAs) for the Hepatitis C virus (HCV) have shifted the World Health Organisation global strategic focus to the elimination of HCV by 2030. In England, the UK Health Security Agency (UKHSA) led a national 'patient re-engagement exercise', using routine surveillance data, which was delivered through the HCV Operational Delivery Networks (ODNs) with support from National Health Service England (NHSE), to help find and support people with a positive HCV PCR test result to access treatment. We report a quantitative evaluation of outcomes of this exercise. METHODS: Individuals with a recorded positive HCV antibody or PCR result between 1996 and 2017 were identified using UKHSA's records of HCV laboratory diagnosis. Linkage with established health-care datasets helped to enhance patient identification and minimise attempts to contact deceased or previously treated individuals. From September to November 2018 each ODN was provided with a local list of diagnosed individuals. ODNs were asked to perform further data quality checks through local systems and then write to each individual's GP to inform them that the individual would be contacted by the ODN to offer confirmatory HCV PCR testing, assessment and treatment unless the GP advised otherwise. Outcomes of interest were receipt of treatment, a negative PCR result, and death. Data were collected in 2022. RESULTS: Of 176,555 individuals with a positive HCV laboratory report, 55,329 individuals were included in the exercise following linkage to healthcare datasets and data reconciliation. Participants in the study had a median age of 51 years (IQR: 43, 59), 36,779 (66.5%) were males, 47,668 (86.2%) were diagnosed before 2016 and 11,148 (20.2%) lived in London. Of the study population, 7,442 (13.4%) had evidence of treatment after the re-engagement exercise commenced, 6,435 (11.6%) were reported as PCR negative (96% had no previous treatment records), 4,195 (7.6%) had prescription data indicating treatment before the exercise commenced or were reported to have been treated previously by their ODN, and 2,990 (5.4%) had died. The status of 32,802 (59.3%) people remains unknown. CONCLUSIONS: A substantial number of those included had treatment recorded after the exercise commenced, however, many more remain unengaged. Evaluation of the exercise highlighted areas that could be streamlined to improve future exercises.

Understanding current antenatal Hepatitis C testing and care in maternity services in England.

OBJECTIVES: Universal opt-out antenatal screening for Hepatitis C virus (HCV) is not currently recommened and it is recommended that maternity services offer risk-based testing. We aimed to investigate antenatal HCV testing and adherence to testing guidance. METHODS: A cross-sectional survey was circulated to maternity service providers between November-December 2020 which included testing policy, training for healthcare staff, and management of women found to be HCV positive. Descriptive data are presented. RESULTS: A total of 75 questionnaires were returned, representing 48 % of English maternity service providers. 87 % of providers reported offering antenatal HCV risk-based testing. Risk factors used to identify pregnant women for testing varied. Less than 15 % of respondents considered women that were ever homeless or with history of incarceraton or from higher HCV prevalence areas as high risk. CONCLUSIONS: Current antenatal HCV testing practices are inadequate and HCV infection likely goes undiagnosed in pregnancy, especially among vulnerable population groups. In the absence of universal antenatal screening, re-framing antenatal HCV risk-based testing and management as a quality improvement initiative and developing HCV specific pathway guidance for maternity units is required.

Blood-borne virus testing in emergency departments - a systematic review of seroprevalence, feasibility, acceptability and linkage to care.

BACKGROUND: Blood-borne viruses (BBVs) cause significant morbidity and mortality worldwide. Emergency departments (EDs) offer a point of contact for groups at increased risk of BBVs who may be less likely to engage with primary care. We reviewed the literature to evaluate whether BBV testing in this setting might be a viable option to increase case finding and linkage to care. METHODS: We searched PubMed database for English language articles published until June 2019 on BBV testing in EDs. Studies reporting seroprevalence surveys, feasibility, linkage to care, enablers and barriers to testing were included. Additional searches for grey literature were performed. RESULTS: Eight-nine articles met inclusion criteria, of which 14 reported BBV seroprevalence surveys in EDs, 54 investigated feasibility and acceptability, and 36 investigated linkage to care. Most studies were HIV-focused and conducted in the USA. Seroprevalence rates were in the range 1.5-17% for HCV, 0.7-1.6% for HBV, and 0.8-13% for HIV. For studies that used an opt-in study design, testing uptake ranged from 2% to 98% and for opt-out it ranged from 16% to 91%. There was a wide range of yield: 13-100% of patients received their test result, 21-100% were linked to care, and 50-91% were retained in care. Compared with individuals diagnosed with HIV, linkage to and retention in care were lower for those diagnosed with hepatitis C. Predictors of linkage to care was associated with certain patient characteristics. CONCLUSIONS: Universal opt-out BBV testing in EDs may be feasible and acceptable, but linkage to care needs to be improved by optimizing implementation. Further economic evaluations of hepatitis testing in EDs are needed.

Long COVID in Children and Young after Infection or Reinfection with the Omicron Variant: A Prospective Observational Study.

To describe the prevalence of long COVID in children infected for the first time (n = 332) or reinfected (n = 243) with Omicron compared with test-negative children (n = 311). Overall, 12%-16% of those infected with Omicron met the research definition of long COVID at 3 and 6 months after infection, with no evidence of difference between cases of first positive and reinfected (Pχ2 = 0.17).

Investigating rates and risk factors for hepatitis C virus reinfection in people receiving antiviral treatment in England.

England has committed to the World Health Organization target to eliminate hepatitis C virus (HCV) as a public threat by the year 2030. Given successful treatments for HCV in recent years, it is unclear whether HCV reinfection will impact England's ability to achieve HCV elimination. We aimed to estimate the HCV reinfection rate among a cohort of patients receiving antiviral treatment using available surveillance data. Linkage between a treatment dataset from 2015 to 2019 and an HCV RNA testing dataset were used to identify people who experienced reinfection using three criteria. A Cox proportional hazards model was used to determine risk factors associated with HCV reinfection among a cohort who received treatment and had follow-up HCV RNA testing. The reinfection rate among those receiving HCV treatment was 7.91 per 100 person-years (PYs, 95% confidence interval (CI) 7.37-8.49) and highest among current injecting drug users (22.55 per 100 PYs, 95% CI 19.98-25.46) and people who had been in prison (20.42 per 100 PYs, 95% CI 17.21-24.24). In the adjusted model, women had a significantly reduced risk of reinfection. Being of younger age, current injecting drug users, and receipt of first treatment in prison were each significantly associated with increased risk of reinfection. Two-fifths of those with reinfection (43%, n = 329/767) were linked to treatment after reinfection, and of those starting treatment, three quarters (75%, n = 222/296) achieved a sustained virologic response. Guidance for testing groups at risk of reinfection and harm reduction strategies to minimize transmission should be implemented if England is to achieve HCV elimination targets.

Retrospective cohort study assessing coverage, uptake and associations with hepatitis B vaccination among females who engage in sex work attending sexual health services in England between 2015 and 2019.

OBJECTIVES: Females who engage in sex work (FSW) are at high risk of hepatitis B virus (HBV) and are eligible for HBV vaccination. The objective of this analysis was to explore coverage, uptake and correlates of HBV vaccination among FSW who attend sexual health services (SHS) in England. METHODS: Data on all attendances at SHS in England were obtained from the GUMCAD STI Surveillance System. Attendees were eligible for inclusion if they were female, had not been previously diagnosed with HIV and sex work was recorded between 2015 and 2019. Bivariable and multivariable logistic regression models were used to investigate sociodemographic factors (age, ethnicity, region of birth and region of residence) associated with having received an HBV vaccination on or after an attendance where sex work was reported. RESULTS: There were 13 769 FSW attending SHS in England between 2015 and 2019 (median age 30 years, 71% white ethnicity). HBV vaccination coverage was 37% (n=5050/13 751, 95% CI 35.9%-37.5%). Among those that first reported sex work between 2015 and 2019, HBV vaccination uptake was 30% (n=3249/10 681, 95% CI 29.6%-31.3%). In multivariable analyses, HBV vaccination uptake was associated with younger age (5-year increase: OR=0.87, 95% CI 0.85, 0.89) and being born in South America (37%, adjusted OR (aOR)=1.40, 95% CI 1.18, 1.66) compared with being born in the UK. Being of Asian ethnicity (19%, aOR=0.63, 95% CI 0.45, 0.89) compared with white ethnicity was associated with reduced odds of HBV vaccination. Sixteen FSW were diagnosed with HBV after their first attendance where sex work was recorded. CONCLUSIONS: To achieve the WHO goals of elimination of HBV as a public health threat by the year 2030, further research is needed to understand the individual and structural barriers to the offering and uptake of HBV vaccination among FSW, as well as using health promotion methods to improve uptake.

Effects of COVID-19 Pandemic Response on Service Provision for Sexually Transmitted Infections, HIV, and Viral Hepatitis, England.

Since the coronavirus disease pandemic response began in March 2020, tests, vaccinations, diagnoses, and treatment initiations for sexual health, HIV, and viral hepatitis in England have declined. The shift towards online and outreach services happened rapidly during 2020 and highlights the need to evaluate the effects of these strategies on health inequalities.

SARS-CoV-2 infection rates of antibody-positive compared with antibody-negative health-care workers in England: a large, multicentre, prospective cohort study (SIREN).

BACKGROUND: Increased understanding of whether individuals who have recovered from COVID-19 are protected from future SARS-CoV-2 infection is an urgent requirement. We aimed to investigate whether antibodies against SARS-CoV-2 were associated with a decreased risk of symptomatic and asymptomatic reinfection. METHODS: A large, multicentre, prospective cohort study was done, with participants recruited from publicly funded hospitals in all regions of England. All health-care workers, support staff, and administrative staff working at hospitals who could remain engaged in follow-up for 12 months were eligible to join The SARS-CoV-2 Immunity and Reinfection Evaluation study. Participants were excluded if they had no PCR tests after enrolment, enrolled after Dec 31, 2020, or had insufficient PCR and antibody data for cohort assignment. Participants attended regular SARS-CoV-2 PCR and antibody testing (every 2-4 weeks) and completed questionnaires every 2 weeks on symptoms and exposures. At enrolment, participants were assigned to either the positive cohort (antibody positive, or previous positive PCR or antibody test) or negative cohort (antibody negative, no previous positive PCR or antibody test). The primary outcome was a reinfection in the positive cohort or a primary infection in the negative cohort, determined by PCR tests. Potential reinfections were clinically reviewed and classified according to case definitions (confirmed, probable, or possible) and symptom-status, depending on the hierarchy of evidence. Primary infections in the negative cohort were defined as a first positive PCR test and seroconversions were excluded when not associated with a positive PCR test. A proportional hazards frailty model using a Poisson distribution was used to estimate incidence rate ratios (IRR) to compare infection rates in the two cohorts. FINDINGS: From June 18, 2020, to Dec 31, 2020, 30 625 participants were enrolled into the study. 51 participants withdrew from the study, 4913 were excluded, and 25 661 participants (with linked data on antibody and PCR testing) were included in the analysis. Data were extracted from all sources on Feb 5, 2021, and include data up to and including Jan 11, 2021. 155 infections were detected in the baseline positive cohort of 8278 participants, collectively contributing 2 047 113 person-days of follow-up. This compares with 1704 new PCR positive infections in the negative cohort of 17 383 participants, contributing 2 971 436 person-days of follow-up. The incidence density was 7·6 reinfections per 100 000 person-days in the positive cohort, compared with 57·3 primary infections per 100 000 person-days in the negative cohort, between June, 2020, and January, 2021. The adjusted IRR was 0·159 for all reinfections (95% CI 0·13-0·19) compared with PCR-confirmed primary infections. The median interval between primary infection and reinfection was more than 200 days. INTERPRETATION: A previous history of SARS-CoV-2 infection was associated with an 84% lower risk of infection, with median protective effect observed 7 months following primary infection. This time period is the minimum probable effect because seroconversions were not included. This study shows that previous infection with SARS-CoV-2 induces effective immunity to future infections in most individuals. FUNDING: Department of Health and Social Care of the UK Government, Public Health England, The National Institute for Health Research, with contributions from the Scottish, Welsh and Northern Irish governments.