COVID-19 vaccine coverage in health-care workers in England and effectiveness of BNT162b2 mRNA vaccine against infection (SIREN): a prospective, multicentre, cohort study.

BACKGROUND: BNT162b2 mRNA and ChAdOx1 nCOV-19 adenoviral vector vaccines have been rapidly rolled out in the UK from December, 2020. We aimed to determine the factors associated with vaccine coverage for both vaccines and documented the vaccine effectiveness of the BNT162b2 mRNA vaccine in a cohort of health-care workers undergoing regular asymptomatic testing. METHODS: The SIREN study is a prospective cohort study among staff (aged ≥18 years) working in publicly-funded hospitals in the UK. Participants were assigned into either the positive cohort (antibody positive or history of infection [indicated by previous positivity of antibody or PCR tests]) or the negative cohort (antibody negative with no previous positive test) at the beginning of the follow-up period. Baseline risk factors were collected at enrolment, symptom status was collected every 2 weeks, and vaccination status was collected through linkage to the National Immunisations Management System and questionnaires. Participants had fortnightly asymptomatic SARS-CoV-2 PCR testing and monthly antibody testing, and all tests (including symptomatic testing) outside SIREN were captured. Data cutoff for this analysis was Feb 5, 2021. The follow-up period was Dec 7, 2020, to Feb 5, 2021. The primary outcomes were vaccinated participants (binary ever vacinated variable; indicated by at least one vaccine dose recorded by at least one of the two vaccination data sources) for the vaccine coverage analysis and SARS-CoV-2 infection confirmed by a PCR test for the vaccine effectiveness analysis. We did a mixed-effect logistic regression analysis to identify factors associated with vaccine coverage. We used a piecewise exponential hazard mixed-effects model (shared frailty-type model) using a Poisson distribution to calculate hazard ratios to compare time-to-infection in unvaccinated and vaccinated participants and estimate the impact of the BNT162b2 vaccine on all PCR-positive infections (asymptomatic and symptomatic). This study is registered with ISRCTN, number ISRCTN11041050, and is ongoing. FINDINGS: 23 324 participants from 104 sites (all in England) met the inclusion criteria for this analysis and were enrolled. Included participants had a median age of 46·1 years (IQR 36·0-54·1) and 19 692 (84%) were female; 8203 (35%) were assigned to the positive cohort at the start of the analysis period, and 15 121 (65%) assigned to the negative cohort. Total follow-up time was 2 calendar months and 1 106 905 person-days (396 318 vaccinated and 710 587 unvaccinated). Vaccine coverage was 89% on Feb 5, 2021, 94% of whom had BNT162b2 vaccine. Significantly lower coverage was associated with previous infection, gender, age, ethnicity, job role, and Index of Multiple Deprivation score. During follow-up, there were 977 new infections in the unvaccinated cohort, an incidence density of 14 infections per 10 000 person-days; the vaccinated cohort had 71 new infections 21 days or more after their first dose (incidence density of eight infections per 10 000 person-days) and nine infections 7 days after the second dose (incidence density four infections per 10 000 person-days). In the unvaccinated cohort, 543 (56%) participants had typical COVID-19 symptoms and 140 (14%) were asymptomatic on or 14 days before their PCR positive test date, compared with 29 (36%) with typical COVID-19 symptoms and 15 (19%) asymptomatic in the vaccinated cohort. A single dose of BNT162b2 vaccine showed vaccine effectiveness of 70% (95% CI 55-85) 21 days after first dose and 85% (74-96) 7 days after two doses in the study population. INTERPRETATION: Our findings show that the BNT162b2 vaccine can prevent both symptomatic and asymptomatic infection in working-age adults. This cohort was vaccinated when the dominant variant in circulation was B1.1.7 and shows effectiveness against this variant. FUNDING: Public Health England, UK Department of Health and Social Care, and the National Institute for Health Research.

Outbreak of uncommon O4 non-agglutinating Salmonella typhimurium linked to minced pork, Saxony-Anhalt, Germany, January to April 2013.

INTRODUCTION: In January 2013, the National Reference Centre for Salmonella (NRC) detected a salmonellosis cluster in Saxony-Anhalt, Germany, caused by uncommon O4 non-agglutinating, monophasic Salmonella (S.) Typhimurium DT193. Circulating predominant monophasic S. Typhimurium DT193 clones typically display resistance phenotype ASSuT. We investigated common exposures to control the outbreak, and conducted microbiological investigations to assess the strains' phenotype. METHODS: We conducted a case-control study defining cases as persons living or working in Saxony-Anhalt diagnosed with the O4 non-agglutinating strain between January and March 2013. We selected two controls contemporarily reported with norovirus infection, frequency-matched on residence and age group, per case. We interviewed regarding food consumption, especially pork and its place of purchase. We calculated odds ratios (ORs) with 95% confidence intervals (95% CI) using logistic regression. The NRC investigated human and food isolates by PCR, SDS-PAGE, MLST, PFGE, MLVA and susceptibility testing. RESULTS: Altogether, 68 O4 non-agglutinating human isolates were confirmed between January and April 2013. Of those, 61 were assigned to the outbreak (median age 57 years, 44% female); 83% cases ≥ 60 years were hospitalized. Eating raw minced pork from butcheries within 3 days was associated with disease (31 cases, 28 controls; OR adjusted for sex: 3.6; 95% CI: 1.0-13). Phage type DT193 and MLST ST34 were assigned, and isolates' lipopolysaccharide (LPS) matched control strains. Isolates linked to Saxony-Anhalt exhibited PFGE type 5. ASSuT- and ACSSuT phenotype proportions were 34 and 39% respectively; 54% were resistant to chloramphenicol. Three pork isolates matched the outbreak strain. DISCUSSION: Raw minced pork was the most likely infection vehicle in this first reported outbreak caused by O4 non-agglutinating, mostly chloramphenicol-resistant S. Typhimurium DT193. High hospitalization proportions demand awareness on the risk of consumption of raw pork among elderly. LPS analysis indicated O4 expression; therefore, testing with antisera from different lots is recommendable in unexpected agglutination reactions.

Effectiveness of the 2012/13 trivalent live and inactivated influenza vaccines in children and adolescents in Saxony-Anhalt, Germany: a test-negative case-control study.

A live attenuated influenza vaccine has been available in Germany since the influenza season 2012/13, which is approved for children aged 2-17 years. Using data from our laboratory-based surveillance system, we described the circulation of influenza and non-influenza respiratory viruses during the influenza season 2012/13 in Saxony-Anhalt. We estimated the effectiveness of live and inactivated trivalent influenza vaccines in preventing laboratory-confirmed cases among children and adolescents. From week 40/2012 to 19/2013, sentinel paediatricians systematically swabbed acute respiratory illness patients for testing of influenza and 5 non-influenza viruses by PCR. We compared influenza cases and influenza-negative controls. Among children aged 2-17 years, we calculated overall and vaccine type-specific effectiveness against laboratory-confirmed influenza, stratified by age group (2-6; 7-17 years). We used multivariable logistic regression to adjust estimates for age group, sex and month of illness. Out of 1,307 specimens, 647 (35%) were positive for influenza viruses and 189 (15%) for at least one of the tested non-influenza viruses. For vaccine effectiveness estimation, we included 834 patients (mean age 7.3 years, 53% males) in our analysis. Of 347 (42%) influenza-positive specimens, 61 (18%) were positive for A(H1N1)pdm09, 112 (32%) for A(H3N2) and 174 (50%) for influenza B virus. The adjusted overall vaccine effectiveness including both age groups was 38% (95% CI: 0.8-61%). The adjusted effectiveness for inactivated vaccines was 37% (95% CI: -35-70%) and for live vaccines 84% (95% CI: 45-95%). Effectiveness for the live vaccine was higher in 2-6 year-old children (90%, 95% CI: 20-99%) than in children aged 7-17 years (74%, 95% CI: -32-95%). Our study of the strong influenza season in 2012/13 suggests a high preventive effect of live attenuated influenza vaccine especially among young children, which could not be reached by inactivated vaccines. We recommend the use of live attenuated influenza vaccines in children unless there are contraindications.

Effectiveness of routine and booster pertussis vaccination in children and adolescents, federal state of Brandenburg, Germany, 2002-2012.

BACKGROUND: In Germany, whole-cell pertussis vaccines were rapidly replaced by high-concentration acellular pertussis-containing vaccines (3+1 doses from 2 months of age) starting in 1995. Boosters were recommended for 9- to 17-year-olds (2000) and for 5- to 6-year-olds (2006). Pertussis incidence remains high despite rising vaccination coverage (VC). Therefore, we analyzed VC and vaccine effectiveness (VE) in the federal state of Brandenburg. METHODS: In a stratified case-cohort analysis, we compared VC of reported pertussis cases with VC assessed in schools and kindergartens in the following strata: Children aged 2-3 years born 2005-2009 (toddlers), 5-7 years born 1995-2006 (pre-schoolers) and 15-16 years born 1995-1996 (adolescents). We calculated VE for primary and booster vaccination using Poisson regression. RESULTS: Four-dose VE decreased from 96.9% in toddlers [95% confidence interval (CI): 72.2-99.3] to 87.8% in pre-schoolers (95% CI: 79.7-92.7) to 81.7% in adolescents (95% CI: 40.6-92.8). Four-dose VE was lower in pre-schoolers born after 1996 (75.4%) than in those born 1995-1996, ~1% and ~21% of whom had received ≥1 dose of whole-cell pertussis vaccines, respectively. VE was higher in pre-schoolers and adolescents who received a booster (92.8%and 96.5%, respectively). However, overall booster VC was only 19% and 76% in these age groups, respectively. CONCLUSIONS: We observed high VE of routine pertussis vaccination, with evidence of waning over time and improved VE after booster vaccination. Increased uptake and monitoring of recommended pertussis boosters is urgently recommended to decrease high pertussis morbidity particularly in older children and adolescents.

An outbreak of gastroenteritis linked to seafood consumption in a remote Northern Aegean island, February-March 2010.

INTRODUCTION: Raw seafood consumption has frequently been linked to gastroenteritis and Norovirus is a common cause. In February and March 2010, there was an increase cases of gastroenteritis on the remote island of Agios Efstratios in the Northern Aegean Sea, Greece. A massive increase in seafood consumption associated with a religious festival a few days prior to the outbreak suggested seafood as the vehicle of transmission. METHODS: An outbreak investigation team visited the island in order to document the outbreak and find epidemiological evidence for its source. The whole island was used as a cohort in the retrospective cohort study that was conducted. RESULTS: Sixty-four of the 181 participants reported having had symptoms of gastroenteritis, of which 34 were considered primary cases. People who consumed any raw seafood imported to the island were 21.5 times (95% CI: 8.95-51.8) more likely to develop symptoms of gastroenteritis in the 72 hours following exposure. Consumption of local seafood was not found to be a risk factor. CONCLUSION: Despite the lack of laboratory evidence, all four Kaplan's criteria were met and the outbreak was thought to have been caused by Norovirus. The outbreak investigation demonstrates epidemiological methods for use in a remote setting, where the means for laboratory and environmental investigation may be absent or limited.

Occupational blood exposure accidents in the Netherlands.

BACKGROUND: To make proper evaluation of prevention policies possible, data on the incidence and associated medical costs of occupational blood exposure accidents in the Netherlands are needed. METHODS: Descriptive analysis of blood exposure accidents and risk estimates for occupational groups. Costs of handling accidents were calculated. RESULTS: Each year, an estimated 13,000-15,000 blood exposure accidents are reported in the Netherlands, 95% in occupational settings. Hepatitis B (HBV) vaccination is offered free of charge only to people in risk groups, the seroprevalence of HBV, hepatitis C (HCV) and human immunodeficiency virus (HIV) is low and few infections are related to blood exposure accidents. High-risk accidents occur mainly in hospitals. In nursing homes and home care settings, the majority of the accidents are low-risk. Limited data are available about occurrence of accidents in other occupational groups. Associated medical costs from occupational blood exposure accidents are mainly determined by the initial risk management. CONCLUSIONS: Accidents must be managed effectively to prevent infection and reduce anxiety in injured employees. While strategies to reduce HCV and HIV infection should be primarily aimed at reducing the occurrence of high-risk accidents, vaccination can prevent HBV infection and cut the costs of handling low-risk accidents. The implementation of vaccination strategies, safe working policies and the proper use of safe equipment should be monitored better.

A prospective, randomized comparison of adrenaline injection in combination with detachable snare versus adrenaline injection alone in the prevention of postpolypectomy bleeding in large colonic polyps.

OBJECTIVES: Our study sought to compare the efficacy of adrenaline injection in combination with detachable snare versus adrenaline injection alone in the prevention of postpolypectomy bleeding in large colonic polyps. METHODS: At the time of colonoscopy, patients with at least one colonic polyp > or =2 cm were randomized to receive treatment either by the injection of a 1:10.000 solution of adrenaline and the position of a detachable snare followed by a conventional snare polypectomy (group A) or injection of adrenaline followed by a conventional snare polypectomy (group B). A total of 159 consecutive patients were randomly assigned to one of the above groups. Out of them, 84 patients (47 men, 37 women, mean age 61 yr) were assigned to group A and 75 (37 men, 38 women, mean age 64 yr) to group B. Early (<24 h) and late (>24 h-30 days) bleeding complications were assessed. RESULTS: Overall bleeding complications occurred in 10/159 (6.2%) of the patients. There were two cases of bleeding in group A (2.3%), and eight in group B (10.6%) (P= 0.04). The number of early bleeding episodes was significantly reduced in group A patients (1 case) compared to that of group B (7 cases) (P= 0.02). In contrast, there was no significant difference between group A and B as far as late bleeding is concerned. CONCLUSIONS: Our data suggest that the use of adrenaline injection in combination with detachable snare may significantly decrease the number of early postpolypectomy bleeding episodes in patients with large colonic polyps.

Herpes simplex virus type 1 in peptic ulcer disease: an inverse association with Helicobacter pylori.

AIM: To assess the frequency of herpes simplex virus type I in upper gastrointestinal tract ulcers and normal mucosa with the modern and better assays and also with a larger number of well characterized patients and controls and its relationship to Helicobacter pylori(H pylori). METHODS: Biopsy specimens from 90 patients (34 with gastric ulcer of the prepyloric area and 56 with duodenal ulcer) were evaluated. Biopsies from 50 patients with endoscopically healthy mucosa were considered as the control group. The method used to identify herpes simplex virus-1 (HSV-1) was polymerase chain reaction. H pylori was detected by the CLO-test and by histological method. RESULTS: Herpes simplex virus-1 was detected in 28 of 90 patients with peptic ulcer (31%) [11 of 34 patients with gastric ulcer (32.4%) and 17 of 56 with duodenal ulcer (30.4%)] exclusively close to the ulcerous lesion. All control group samples were negative for HSV-1. The likelihood of H pylori negativity among peptic ulcer patients was significantly higher in HSV-1 positive cases than in HSV-1 negative cases (P = 0.009). Gastric ulcer patients with HSV-1 positivity were strongly associated with an increased possibility of Helicobacter pylori negativity compared to duodenal ulcer patients (P = 0.010). CONCLUSION: HSV-1 is frequent in upper gastro-intestinal tract ulcers but not in normal gastric and duodenal mucosa. There is an inverse association between HSV-1 and H pylori infection.