Association of known SARS-CoV-2 serostatus and adherence to personal protection measures and the impact of personal protective measures on seropositivity in a population-based cross-sectional study (MuSPAD) in Germany.

BACKGROUND: In 2020/2021 in Germany, several non-pharmacological interventions were introduced to lower the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We investigated to what extent knowledge of prior infection with SARS-CoV-2 or vaccination status influenced the use of personal protection measures (PPM). Further, we were interested in the effect of compliance with PPM on SARS-CoV-2 serostatus. METHODS: Data was based on a sequential, multilocal seroprevalence study (MuSPAD), carried out in eight locations from July 2020 to August 2021. We estimated the association between a known SARS-CoV-2 serostatus (reported positive PCR test or vaccination) and self-reported PPM behavior (hand hygiene, physical distancing, wearing face mask), just as the association of PPM compliance with seropositivity against nucleocapsid (NC), receptor-binding domain (RBD), and spike protein (S) antigens. We identified relevant variables and deduced adjustment sets with directed acyclic graphs (DAG), and applied mixed logistic regression. RESULTS: Out of the 22,297 participants (median age: 54 years, 43% male), 781 were classified as SARS-CoV-2-infected and 3,877 had a vaccinated immune response. Vaccinated individuals were less likely to keep 1.5 m distance [OR = 0.74 (95% CI: 0.57-0.97)] and only partly physically distanced [OR = 0.71 (95% CI: 0.58-0.87)]. Participants with self-reported positive PCR test had a lower chance of adhering partly to physical distancing [OR = 0.70 (95% CI: 0.50-0.99)] in comparison to the reference group. Higher odds of additionally wearing a face mask was observed in vaccinated [OR = 1.28 (95% CI: 1.08-1.51)] even if it was not obligatory. Overall, among unvaccinated participants, we found little evidence of lower odds of seropositivity given mask wearing [OR: 0.91 (95% CI: 0.71-1.16)], physical distancing [OR: 0.84 (95% CI: 0.59-1.20)] and no evidence for completely adhering to hand cleaning [OR: 0.97 (95% CI: 0.29-3.22)]. CONCLUSIONS: A known confirmed prior infection and vaccination may have the potential to influence adherence to PPM.

Country-specific food culture and scientific knowledge transfer events - Do they influence the purchasing behaviour of seafood products?

A positive perception of aquaculture products is essential to boost production by using more sustainable and eco-friendly solutions. However, consumer perception and resulting purchasing decisions remain poorly understood. In most European countries, the consumer perception tends to be rather negative, which is reinforced by knowledge gaps and misleading information from the media. This is believed to have the greatest impact on the current low consumption rate of farmed fish across Europe. Previous research has suggested that consumers may often be reluctant to change their seafood purchasing behaviour despite having a solid scientific understanding of aquaculture products and their mode of production. In this study, we investigated the extent to which country-specific contexts and degree of scientific knowledge contribute to the purchasing behaviour of consumers across Europe. To this end, interactive poster surveys and semi-structured interviews were conducted at eight different knowledge transfer events (KTEs) across three countries, targeting 383 participants. The application of a yet underutilized method, an interactive poster survey, underscored the need to use new approaches to tackle consumer behaviour. Our results indicate that increased scientific knowledge does not lead to changes in purchasing behaviour per se. Perceptions and purchasing habits are very contextual and vary from culture to culture. This points to the highly interlinked nature of country-specific marine food culture that ranges between individual awareness, scientific knowledge, and socio-cultural contexts, all of which renders in resulting individual purchasing decisions. Our results suggest focusing more on the sustainability of a product and emphasising the ongoing transition towards a circular economy approach in the aquaculture sector may be a promising pathway to foster more sustainability-driven purchasing decisions in the seafood sector. Our findings also question whether trying to educate the public about more sustainable purchasing criteria is really the key to foster more sustainable consumption patterns or whether we are working from misleading assumptions that lead to wrong approaches. In conclusion, a lack of clear and easily accessible information appears to be the main barrier to social acceptance of sustainable aquaculture products in Europe.

Interlaboratory proficiency tests for the detection of staphylococcal enterotoxin type A in food.

Staphylococcal enterotoxins (SEs) are among the leading causes of food intoxications, affecting consumer health even in nanogram (ng) amounts. In the European Union, certain food safety criteria are specified, including the absence of SEs in cheeses, milk powder and whey powder. Until 2019, the analytical reference method used was the European Screening Method, which was replaced by EN ISO 19020. For the official laboratories involved in food control, the German Reference Laboratory for coagulase-positive staphylococci including Staphylococcus aureus organized three interlaboratory proficiency tests (ILPTs) to detect SE type A in food during the years 2013-2018. The selected food products (cream cheese and vanilla pudding) were successfully tested beforehand with regard to easy handling, homogeneity and stability of the added toxin. In 2013, ILPT participants overall were not competent in detecting SE type A in food. The following factors were identified to improve the performance: (i) concentration of sample extract using dialysis; (ii) selection of a sensitive detection kit; and (iii) proper sample handling. By taking these factors into account and instructing and training the laboratories, their competence greatly improved. In 2018, all performance criteria (specificity, sensitivity and accuracy) were >90%, even at very low concentrations of SE type A of approximately 0·01 ng g-1 food.

User preferences for a mobile application to report adverse events following vaccination.

The passive surveillance system is an important tool in pharmacovigilance of vaccines. However, reporting of adverse events following immunization (AEFI) post-marketing has limitations regarding under-reporting, biased reports and lack of exposure data resulting in imprecise estimates. New mobile application technology may provide an opportunity for an enhanced surveillance. A pre-requisite for the use of new app-based technology is to identify practical challenges and end users' preferences for design of app-features. The objectives were (i) to investigate the recruitment and feasibility of an app-based study in Germany, (ii) to assess individuals' motivation to participate in such a study and (iii) to identify app-features for reporting AEFI. We conducted a cross-sectional study among employees of a financial institution who attended the occupational health office during the seasonal influenza vaccination in November 2017. Participants tested feasibility and assessed an app prototype for AEFI reporting by using a case vignette and a questionnaire. Of the 153 attending employees, 65 (42%) agreed to participate and returned the questionnaire. Twenty-three (63%) rated the experience of reporting AEFI with the app prototype to be positive. Among three features offered for gamification, collecting points was most frequently chosen (n=22, 34%). The main reason for declining participation was the apprehension about data protection (n=28, 43%). Results suggest that the app-based technology was well accepted and is a suitable supplement for AEFI reporting and in our study. A convincing data protection concept is likely to enhance acceptability of such a system.

Photosynthetic heat tolerance of shade and sun leaves of three tropical tree species.

Previous studies of heat tolerance of tropical trees have focused on canopy leaves exposed to full sunlight and high temperatures. However, in lowland tropical forests with leaf area indices of 5-6, the vast majority of leaves experience varying degrees of shade and a reduced heat load compared to sun leaves. Here we tested whether heat tolerance is lower in shade than in sun leaves. For three tropical tree species, Calophyllum inophyllum, Inga spectabilis, and Ormosia macrocalyx, disks of fully developed shade and sun leaves were subjected to 15-min heat treatments, followed by measurement of chlorophyll a fluorescence after 48 h of recovery. In two of the three species, the temperature causing a 50% decrease of the fluorescence ratio Fv/Fm (T50) was significantly lower (by ~ 1.0 °C) in shade than in sun leaves, indicating a moderately decreased heat tolerance of shade leaves. In shade leaves of these two species, the rise in initial fluorescence, F0, also occurred at lower temperatures. In the third species, there was no shade-sun difference in T50. In situ measurements of photosynthetic CO2 assimilation showed that the optimum temperature for photosynthesis tended to be lower in shade leaves, although differences were not significant. At supra-optimal temperatures, photosynthesis was largely constrained by stomatal conductance, and the high-temperature CO2 compensation point, TMax, occurred at considerably lower temperatures than T50. Our study demonstrates that the temperature response of shade leaves of tropical trees differs only marginally from that of sun leaves, both in terms of heat tolerance and photosynthetic performance.

A tribute to Ulrich Heber (1930-2016) for his contribution to photosynthesis research: understanding the interplay between photosynthetic primary reactions, metabolism and the environment.

The dynamic and efficient coordination of primary photosynthetic reactions with leaf energization and metabolism under a wide range of environmental conditions is a fundamental property of plants involving processes at all functional levels. The present historical perspective covers 60 years of research aiming to understand the underlying mechanisms, linking major breakthroughs to current progress. It centers on the contributions of Ulrich Heber who had pioneered novel concepts, fundamental methods, and mechanistic understanding of photosynthesis. An important first step was the development of non-aqueous preparation of chloroplasts allowing the investigation of chloroplast metabolites ex vivo (meaning that the obtained results reflect the in vivo situation). Later on, intact chloroplasts, retaining their functional envelope membranes, were isolated in aqueous media to investigate compartmentation and exchange of metabolites between chloroplasts and external medium. These studies elucidated metabolic interaction between chloroplasts and cytoplasm during photosynthesis. Experiments with isolated intact chloroplasts clarified that oxygenation of ribulose-1.5-bisphosphate generates glycolate in photorespiration. The development of non-invasive optical methods enabled researchers identifying mechanisms that balance electron flow in the photosynthetic electron transport system avoiding its over-reduction. Recording chlorophyll a (Chl a) fluorescence allowed one to monitor, among other parameters, thermal energy dissipation by means of 'nonphotochemical quenching' of the excited state of Chl a. Furthermore, studies both in vivo and in vitro led to basic understanding of the biochemical mechanisms of freezing damage and frost tolerance of plant leaves, to SO2 tolerance of tree leaves and dehydrating lichens and mosses.

Sex- and age patterns in incidence of infectious diseases in Germany: analyses of surveillance records over a 13-year period (2001-2013).

Sex differences in the incidence of infections may indicate different risk factors and behaviour but have not been analysed across pathogens. Based on 3.96 million records of 33 pathogens in Germany, notified from 2001 to 2013, we applied Poisson regression to generate age-standardised incidence rate ratios and assessed their distribution across age and sex. The following trends became apparent: (a) pathogens with male incidence preponderance at infant and child age (meningococcal disease (incidence rate ratio (IRR) = 1.19, 95% CI 1.03-1.38, age = 0-4); influenza (IRR = 1.09, 95% CI 1.06-1.13, age = 0-4)), (b) pathogens with sex-switch in incidence preponderance at puberty (e.g. norovirus (IRR = 1.10, 95% CI 1.02-1.19 in age = 5-14, IRR = 0.96, 95% CI 0.93-0.99, age ⩾ 60), (c) pathogens with general male incidence preponderance (bacterial/parasitic infections with campylobacter, Yersinia and Giardia), (d) pathogens with male incidence preponderance at juvenile and adult age (sexually transmitted or vector-borne infections (combined-IRR = 2.53, 95% CI 2.36-2.71, age = 15-59), (e) pathogens with male preponderance at older age (tick-borne encephalitis - IRR = 2.75, 95% CI 1.21-6.24, listeriosis - IRR = 2.06, 95% CI 1.38-3.06, age ⩾ 60). Risk factor concepts only partly serve to interpret similarities of grouped infections, i.e. transmission-related explanations and sex-specific exposures not consistently explain the pattern of food-borne infections (b). Sex-specific differences in infectious disease incidence are well acknowledged regarding the sexually transmitted diseases. This has led to designing gender-specific prevention strategies. Our data suggest that for infections with other transmission routes, gender-specific approaches can also be of benefit and importance.

Epidemiology and risk factors of peri-implantitis: A systematic review.

The purpose of this systematic review and meta-analysis was to assess the prevalence, incidence and risk factors of peri-implantitis in the current literature. An electronic search was performed to identify publications from January 1980 until March 2016 on 9 databases. The prevalence and incidence of peri-implantitis were assessed in different subgroups of patients and the prevalences were adjusted for sample size (SSA) of studies. For 12 of 111 identified putative risk factors and risk indicators, forest plots were created. Heterogeneity analysis and random effect meta-analysis were performed for selected potential risk factors of peri-implantitis. The search retrieved 8357 potentially relevant studies. Fifty-seven studies were included in the systematic review. Overall, the prevalence of peri-implantitis on implant level ranged from 1.1% to 85.0% and the incidence from 0.4% within 3 years, to 43.9% within 5 years, respectively. The median prevalence of peri-implantitis was 9.0% (SSA 10.9%) for regular participants of a prophylaxis program, 18.8% (SSA 8.8%) for patients without regular preventive maintenance, 11.0% (SSA 7.4%) for non-smokers, 7.0% (SSA 7.0%) among patients representing the general population, 9.6% (SSA 9.6%) for patients provided with fixed partial dentures, 14.3% (SSA 9.8%) for subjects with a history of periodontitis, 26.0% (SSA 28.8%) for patients with implant function time ≥5 years and 21.2% (SSA 38.4%) for ≥10 years. On a medium and medium-high level of evidence, smoking (effect summary OR 1.7, 95% CI 1.25-2.3), diabetes mellitus (effect summary OR 2.5; 95% CI 1.4-4.5), lack of prophylaxis and history or presence of periodontitis were identified as risk factors of peri-implantitis. There is medium-high evidence that patient's age (effect summary OR 1.0, 95% CI 0.87-1.16), gender and maxillary implants are not related to peri-implantitis. Currently, there is no convincing or low evidence available that identifies osteoporosis, absence of keratinized mucosa, implant surface characteristics or edentulism as risk factors for peri-implantitis. Based on the data analyzed in this systematic review, insufficient high-quality evidence is available to the research question. Future studies of prospective, randomized and controlled type including sufficient sample sizes are needed. The application of consistent diagnostic criteria (eg, according to the latest definition by the European Workshop on Periodontology) is particularly important. Very few studies evaluated the incidence of peri-implantitis; however, this study design may contribute to examine further the potential risk factors.

Assembly and function of claudins: Structure-function relationships based on homology models and crystal structures.

The tetra-span transmembrane proteins of the claudin family are critical components of formation and function of tight junctions (TJ). Homo- and heterophilic side-by-side (cis) and intercellular head-to-head (trans) interactions of 27 claudin-subtypes regulate tissue-specifically the paracellular permeability and/or tightness between epithelial or endothelial cells. This review highlights the functional impact that has been identified for particular claudin residues by relating them to structural features and architectural characteristics in the light of structural advances, which have been contributed by homology models, cryo-electron microscopy and crystal structures. The differing contributions to the TJ functionalities by claudins are dissected for the transmembrane region, the first and the second extracellular loop of claudins separately. Their particular impact to oligomerisation and TJ strand- and pore-formation is surveyed. Detailed knowledge about structure-function relationships about claudins helps to reveal the molecular mechanisms of TJ assembly and regulation of paracellular permeability, which is yet not fully understood.

Expanding marine protected areas to include degraded coral reefs.

Marine protected areas (MPAs) are a commonly applied solution to coral reef degradation, yet coral reefs continue to decline worldwide. We argue that expanding the range of MPAs to include degraded reefs (DR-MPA) could help reverse this trend. This approach requires new ecological criteria for MPA design, siting, and management. Rather than focusing solely on preserving healthy reefs, our approach focuses on the potential for biodiversity recovery and renewal of ecosystem services. The new criteria would help identify sites with the highest potential for recovery and the greatest resistance to future threats (e.g., increased temperature and acidification) and sites that contribute to MPA connectivity. The DR-MPA approach is a compliment rather than a substitute for traditional MPA design approaches. We believe that the DR-MPA approach can enhance the natural, or restoration-assisted, recovery of DRs and their ecosystem services; increase total reef area available for protection; promote more resilient and better-connected MPA networks; and improve conditions for human communities dependent on MPA ecosystem services.

Co-location of passive gear fisheries in offshore wind farms in the German EEZ of the North Sea: A first socio-economic scoping.

Worldwide the renewable energy sector is expanding at sea to address increasing demands. Recently the race for space in heavily used areas such as the North Sea triggered the proposal of co-locating other activities such as aquaculture or fisheries with passive gears in offshore wind farms (OWFs). Our interdisciplinary approach combined a quantification of spatial overlap of activities by using Vessel Monitoring System and logbook data with a stakeholder consultation to conclude and verify on the actual feasibility of co-location. In the German Exclusive Economic Zone (EEZ) of the North Sea up to 90% of Danish and 40% of German annual gillnet fleet landings of plaice overlapped with areas where OWFs are developed. Our results indicated further that the international gillnet fishery could lose up to 50% in landings within the North Sea German EEZ when OWF areas are closed entirely for fisheries. No spatial overlap was found for UK potters targeting brown crab in the German EEZ. We further identified a number of key issues and obstacles that to date hinder an actual implementation of co-location as a measure in the marine spatial planning process: defining the legal base; implementation of safety regulations; delineation of minimum requirements for fishing vessels such as capacities, quotas, technical equipment; implementation of a licensing process; and scoping for financial subsidies to set up business. The stakeholder consultation verified the scientific findings and highlighted that all those points need to be addressed in a planning process. In the German EEZ we have shown that the socio-economic importance of spatial overlap varies within planning boundaries. Therefore we recommend an interdisciplinary bottom-up approach when scoping for suitable areas of co-location. Hence, an informed marine spatial planning process requires comprehensive and spatial explicit socio-economic viability studies factoring in also ecological effects of OWFs on target species.

Improved coverage and timing of childhood vaccinations in two post-Soviet countries, Armenia and Kyrgyzstan.

BACKGROUND: Timing of childhood vaccinations has received close attention in many countries. Little is known about the trends in correctly timed vaccination in former Soviet countries. We examined trends in vaccination coverage and correct timing of vaccination in two post-Soviet countries, Armenia and Kyrgyzstan, and analyzed factors associated with delayed vaccinations. METHODS: We used data from the Demographic and Health Surveys; the surveys were conducted in 2000 (n = 1726), 2005 (n = 1430) and 2010 (n = 1473) in Armenia and in 1997 (n = 1127) and 2012 (n = 4363) in Kyrgyzstan. We applied the Kaplan-Meier method to estimate age-specific vaccination coverage with diphtheria, tetanus and pertussis (DTP) vaccine and a measles-containing vaccine (MCV). A Cox proportional hazard regression with shared frailty was used to examine factors associated with delayed vaccinations. RESULTS: Vaccination coverage for all three doses of the DTP vaccine increased in Armenia from 92 % in 2000 to 96 % in 2010. In Kyrgyzstan, DTP coverage was 96 % and 97 % in 1997 and 2012, respectively. Vaccination coverage for MCV increased from 89 % (Armenia, 2000) and 93 % (Kyrgyzstan, 1997) to 97 % (Armenia, 2010) and 98 % (Kyrgyzstan, 2012). The proportion of children with correctly timed vaccinations increased over time for all examined vaccinations in both countries. For example, the proportion of children in Armenia with correctly timed first DTP dose (DTP1) increased from 46 % (2000) to 66 % (2010). In Kyrgyzstan, the proportion of correctly timed DTP1 increased from 75 % (1997) to 87 % (2012). In Armenia, delays in the third DTP dose (DTP3) and MCV vaccinations were less likely to occur in the capital, whereas in Kyrgyzstan DTP3 and MCV start was delayed in the capital compared to other regions of the country. Also, in Armenia living in urban areas was associated with delayed vaccinations. CONCLUSIONS: Vaccination coverage and timing of vaccination improved over the last years in both countries. Further efforts are needed to reduce regional differences in timely vaccinations.

Surveillance and Outbreak Response Management System (SORMAS) to support the control of the Ebola virus disease outbreak in West Africa.

In the context of controlling the current outbreak of Ebola virus disease (EVD), the World Health Organization claimed that 'critical determinant of epidemic size appears to be the speed of implementation of rigorous control measures', i.e. immediate follow-up of contact persons during 21 days after exposure, isolation and treatment of cases, decontamination, and safe burials. We developed the Surveillance and Outbreak Response Management System (SORMAS) to improve efficiency and timeliness of these measures. We used the Design Thinking methodology to systematically analyse experiences from field workers and the Ebola Emergency Operations Centre (EOC) after successful control of the EVD outbreak in Nigeria. We developed a process model with seven personas representing the procedures of EVD outbreak control. The SORMAS system architecture combines latest In-Memory Database (IMDB) technology via SAP HANA (in-memory, relational database management system), enabling interactive data analyses, and established SAP cloud tools, such as SAP Afaria (a mobile device management software). The user interface consists of specific front-ends for smartphones and tablet devices, which are independent from physical configurations. SORMAS allows real-time, bidirectional information exchange between field workers and the EOC, ensures supervision of contact follow-up, automated status reports, and GPS tracking. SORMAS may become a platform for outbreak management and improved routine surveillance of any infectious disease. Furthermore, the SORMAS process model may serve as framework for EVD outbreak modeling.

The disease burden of hepatitis B, influenza, measles and salmonellosis in Germany: first results of the burden of communicable diseases in Europe study.

Setting priorities in the field of infectious diseases requires evidence-based and robust baseline estimates of disease burden. Therefore, the European Centre for Disease Prevention and Control initiated the Burden of Communicable Diseases in Europe (BCoDE) project. The project uses an incidence- and pathogen-based approach to measure the impact of both acute illness and sequelae of infectious diseases expressed in disability-adjusted life years (DALYs). This study presents first estimates of disease burden for four pathogens in Germany. The number of reported incident cases adjusted for underestimation served as model input. For the study period 2005-2007, the average disease burden was estimated at 33 116 DALYs/year for influenza virus, 19 115 DALYs/year for Salmonella spp., 8708 DALYs/year for hepatitis B virus and 740 DALYs/year for measles virus. This methodology highlights the importance of sequelae, particularly for hepatitis B and salmonellosis, because if omitted, the burden would have been underestimated by 98% and 56%, respectively.

[Seasonal and pandemic influenza vaccination: coverage and attitude among private physicians in Germany]. / Saisonale und pandemische Influenzaimpfung: Impfquoten und Einstellung niedergelassener Ärzte in Deutschland.

BACKGROUND: General practitioners serve as important multipliers for seasonal influenza vaccination in risk groups such as elderly or chronically ill persons, for whom vaccination is recommended in Germany by the Standing Committee on Vaccination (STIKO). Moreover, physicians are a target group for influenza vaccination themselves. METHODS: Data from 1 590 telephone interviews were analysed. The study population comprised private physicians from 4 different disciplines (general and internal medicine, gynaecology, paediatrics). We assessed seasonal and pandemic vaccination coverage, attitudes and informational needs related to vaccination in general, and opinions about the pandemic situation 2009. RESULTS: Of the interviewed physicians, 61% stated that they have been vaccinated against seasonal influenza regularly. Main reasons for not/only occasionally having received a flu shot were: the belief that seasonal influenza vaccination is not necessary for them (78%) or having forgotten about the vaccination (28%). The interviewed physicians expressed a great demand for active information on STIKO recommendations and certain aspects of the seasonal influenza vaccination. There was a significant association between physicians' own influenza vaccination status and the provision of vaccination information materials, utilisation of a data management system for the vaccination of patients, and active vaccination reminders in the physicians' office. In 2009/10, almost 60% had received a pandemic influenza A(H1N1) vaccination. A major barrier to vaccine uptake was the mistrust in the safety of H1N1 vaccines (stated by 54% of non-vaccinees). Information for the public and physicians by the German public health authorities during the pandemic was rather critically appraised by the respondents. CONCLUSION: Compared to other subgroups of health-care workers, among private physicians seasonal and pandemic vaccine uptake was rather high. The physicians' need for more information on vaccination topics can be met by intensified publishing and communication activities of STIKO and by using existing physician-information channels.

Web-based questionnaires to capture acute infections in long-term cohorts : findings of a feasibility study.

BACKGROUND: Incidence of acute respiratory infections (ARI) and gastrointestinal infections (GII) are difficult to assess due to high frequency episodes, limited severity and short duration. Retrospective assessments therefore are particularly prone to recall bias, while prospective assessment with conventional questionnaires requires high discipline from participants which is difficult to maintain over longer time periods. Web-based questionnaires (WQ) allow integration of a recall system and thus carry the potential to prospectively capture acute infections. We investigated the feasibility of a weekly WQ assessing symptoms of ARI and GII among participants of the German National Cohort (GNC). MATERIAL AND METHODS: In the study centres Hamburg and Bremen of the GNC participants of the Pretest 1 phase (September to November 2011) were invited to additionally take part in this feasibility study testing the WQ. Every Monday participants received an e-mail, containing a link to the WQ, asking for occurrence of ARI or GII symptoms during the past 7 days. The study took place from the beginning of February until mid-July 2012. We calculated the overall proportion of participation, weekly participation and the number of weekly reports per participant and we estimated incidences of ARI, ILI and GII. RESULTS: Of 200 Pretest 1 participants 171 (86 %) reported having an email address and thus were eligible for the web-based study. A total of 167 (98 %) agreed to participate. Participants of the web-based study were younger and better educated than non-participants. Access to Internet decreased with increasing age. Of the 167 participants in the feasibility study, 144 (86 %) responded at least once during the study period of 23 weeks, 5 persons (3 %) had non-functioning email addresses and 18 (11 %) did not respond at all. The weekly response varied between 62 % and 81 %, the median was 74 % (IQR: 71-77 %). Weekly median reports per person were 20 (IQR: 14-22; range 1-23). More than 90 % of participants responded during the first 3 days. The following mean incidence rates were found: ARI, 12 %; ILI, 0.49 %; and GII, 3 %. CONCLUSION: Use of WQ in prospective studies seems well possible, as Internet access is frequent among study participants and major technical problems did not occur. We observed high participation during the study period of 6 months and low drop out numbers. Participants of the web-based study were slightly younger and better educated than non-participants, so selection bias is possible and must be kept in mind when discussing generalizability of the results.

Test-retest reliability of an infectious disease questionnaire and evaluation of self-assessed vulnerability to infections : findings of Pretest 2 of the German National Cohort.

INTRODUCTION/OBJECTIVES: Large scale population-based studies focusing on infectious diseases are scarce. This may be explained by methodological obstacles concerning ascertainment of data on infectious diseases requiring, e.g. collection of data on relatively short-termed symptoms and/or collection of biosamples for pathogen identification during a narrow time window. In the German National Cohort (GNC), a novel self-administered questionnaire will be used in addition to biosampling to collect data on selected infectious diseases and symptoms. The aim of this study was to evaluate in Pretest 2 of the GNC newly added items on self-assessed vulnerability to several infectious diseases and to assess test-retest reliability of the questionnaire. METHODS: The study was conducted in two study centres (Hamburg and Hanover) during Pretest 2 of the GNC. A self-administered paper questionnaire was applied. In Hamburg, participants were asked to fill in the questionnaire during their regular visit at the study centre. For test-retest reliability, participants in Hanover filled in the same questionnaire at home twice. To evaluate agreement, item-related percentage agreement and kappa (κ) were calculated. In addition, we computed Bennet's S and Krippendorf's alpha (α). Items on self-assessed vulnerability to infections were evaluated by comparing them with the corresponding self-reported frequency of infections. An explanatory factor analysis was applied to construct the scores of self-reported infection frequency and self-assessed vulnerability to infections. RESULTS: The evaluation of the internal consistency of the five-item instrument of self-assessed vulnerability to infections resulted in a Cronbach's α of 0.78. The factor analysis yielded evidence of one factor. The factor was divided into three groups (lowest quintile classified as "less prone to infections" compared to peers; second, middle and fourth quintiles classified as "similarly prone to infections" and highest quintile classified as "more prone to infections"). Participants classified as "less prone to infections" reported fewer infections than participants classified as "more prone to infections". Spearman's correlation of the two scores (self-reported infection frequency and self-assessed vulnerability to infection) was 0.50 (p < 0.0001). For quantifying reliability, 88 participants with a median time of 8 days between filling in both questionnaires could be included in the analysis; for items sensitive to disease occurrence between both questionnaires only participants with no relevant disease in this time interval were included (n = 75). The weighted κ ranged between 0.65 and 0.87 for the items on infectious disease frequency in the last 12 months, for items on symptom frequency in the past 12 months between 0.77 and 0.90, and for items on vulnerability compared to peers between 0.68 and 0.76. CONCLUSION: A five-item instrument on self-assessed vulnerability to infections seems to be promising, but requires further evaluation. Overall, the questionnaire on self-reported infectious diseases used in Pretest 2 of the GNC is a moderately reliable instrument and, thus, can be applied in future studies on infectious diseases.

Collection of vaccination data in the German National Cohort : Findings of a feasibility study in three study centers.

BACKGROUND: Data about the vaccination status of participants are required in epidemiological cohort studies whenever infection or immunity is considered as potential exposure or outcome. Within Pretest 2 of the German National Cohort (GNC) we therefore investigated the acceptance and feasibility of extracting vaccination status from vaccination certificates provided by the participants of the study. METHODS: This study was conducted in three study centers (Bremen, n = 73; Hamburg, n = 200; Hannover, n = 193). In order to test if an additional reminder would prevent participants from forgetting their vaccination certificates at home persons willing to participate in Pretest 2 were randomly assigned to one of three invitation groups (IG). About one third of the participants received either no further reminder (IG1), a reminder card together with the appointment letter (IG2) or a separate reminder card 4 days before the appointment (IG3). At the study center, vaccination data were scanned or copied and entered into a database using a unique identification number. Participants were also asked to fill in a short questionnaire to assess the completeness of the provided vaccination data. Additionally, in one of the three participating study centers, general practitioners (GP) were asked to provide vaccination data from their records following respective participants' consent. Finally, we compared the influenza data from the vaccination certificates with the influenza data obtained from participants in Pretest 2 by use of a self-administered questionnaire (ID-Screen). RESULTS: Due to different starting dates of the study the intended reminder procedure was implemented only in Hamburg and Hannover. In Hamburg, significantly more vaccination certificates were submitted by the group which received the reminder card separately 4 days before the examination (IG3) compared to IG1 and IG2 (p = 0.04). In Hannover, in contrast, most vaccination certificates were brought by those who received the reminder card together with the appointment letter. Overall, the use of a reminder card had a positive but not significant effect as 89 % (185/209) of participants who received the reminder card submitted vaccination data versus 81 % (84/104) of participants who did not receive any reminder card (p = 0.06). Of all Pretest 2 participants in Hannover, 62 % (120/193) gave written consent for data collection by the GPs. In total, 114 practices were contacted of which 49 (43 %) sent vaccination data. All in all, 360 vaccination certificates with 5065 documented vaccinations were entered into a database, of which 4830 (95 %) were valid for analysis covering a period from 1946 to 2012. The comparison of influenza vaccination data from vaccination certificates to the remembered data from a self-completed questionnaire showed an agreement of data in 46 % (84/184) of cases (Kappa = 0.48). Influenza vaccinations were underreported in 4 % (7/170) of self-completed questionnaires. CONCLUSION: The reliable documentation of vaccinations within the context of the GNC proved to be feasible and thus recommendable at a large scale within the GNC as participants showed high willingness and compliance in providing available vaccination documents. An additional validation by means of documents provided by physicians seems to be possible for more than a quarter of participants. In order to maximize the likelyhood of participants' of bringing their vaccination certificates it would be sufficient to send a reminder card together with the appointment letter.

Comparison of stool collection on site versus at home in a population-based study : feasibility and participants' preference in Pretest 2 of the German National Cohort.

BACKGROUND: For certain laboratory investigations it is necessary to obtain native stool samples and process them within a narrow time window at the point of contact or a nearby laboratory. However, it is not known whether it is feasible to obtain stool samples from asymptomatic individuals during an appointment in a study center (SC). We therefore compared participants' preference, feasibility and acceptance of stool sample collection during the appointment at the study center (on-site sampling) to collection at home after the appointment. METHODS: The study was conducted at two sites in Northern Germany (Bremen, n = 156; Hannover, n = 147) during the Pretest 2 phase of the German National Cohort (GNC), drawing upon a randomly selected population supplemented by a small convenience sample. In the study center, the participants were given the choice to provide a stool sample during the appointment or to collect a sample later at home and return it by mail. RESULTS: In all, 303 of the 351 participants (86 %) of Pretest 2 at these sites participated in this feasibility study. Only 7.9 % (24/303) of the participants chose on-site collection, whereas 92 % (279/303) chose at-home collection. There were significant differences between the two study sites in that 14 % (21/147) of participants in Hannover and 2 % (3/156) of participants in Bremen chose on-site collection. Compliance was high in both groups, as 100 % (24/24) and 98 % (272/279) of participants in the on-site and at-home groups, respectively, provided complete samples. Both methods were highly accepted, as 92 % of the participants in each group (22/24 and 227/248) stated that stool collection at the respective site was acceptable. CONCLUSION: When given a choice, most participants in this population-based study preferred home collection of stool samples to collection in the study center. Thus, native stool samples for immediate processing in the study center may potentially be obtained only from a subpopulation of participants, which may lead to selection bias. Home collection, on the other hand, proved to be a highly feasible method for studies that do not require freshly collected native stool.