Case-control study of behavioural and societal risk factors for sporadic SARS-CoV-2 infections, Germany, 2020-2021 (CoViRiS study).

During the COVID-19 pandemic in Germany, a variety of societal activities were restricted to minimize direct personal interactions and, consequently, reduce SARS-CoV-2 transmission. The aim of the CoViRiS study was to investigate whether certain behaviours and societal factors were associated with the risk of sporadic symptomatic SARS-CoV-2 infections. Adult COVID-19 cases and frequency-matched population controls were interviewed by telephone regarding activities that involved contact with other people during the 10 days before illness onset (cases) or before the interview (controls). Associations between activities and symptomatic SARS-CoV-2 infection were analysed using logistic regression models adjusted for potential confounding variables. Data of 859 cases and 1 971 controls were available for analysis. The risk of symptomatic SARS-CoV-2 infection was lower for individuals who worked from home (adjusted odds ratio (aOR) 0.5; 95% confidence interval (CI) 0.3-0.6). Working in a health care setting was associated with a higher risk (aOR: 1.5; 95% CI: 1.1-2.1) as were private indoor contacts, personal contacts that involved shaking hands or hugging, and overnight travelling within Germany. Our results are in line with some of the public health recommendations aimed at reducing interpersonal contacts during the COVID-19 pandemic.

A shift from travel-associated cases to autochthonous transmission with Berlin as epicentre of the monkeypox outbreak in Germany, May to June 2022.

By 22 June 2022, 521 cases of monkeypox were notified in Germany. The median age was 38 years (IQR: 32-44); all cases were men. In Berlin, where 69% of all cases occurred, almost all were men who have sex with men. Monkeypox virus likely circulated unrecognised in Berlin before early May. Since mid-May, we observed a shift from travel-associated infections to mainly autochthonous transmission that predominantly took place in Berlin, often in association with visits to clubs and parties.

Investigation of an international outbreak of multidrug-resistant monophasic Salmonella Typhimurium associated with chocolate products, EU/EEA and United Kingdom, February to April 2022.

An extensive multi-country outbreak of multidrug-resistant monophasic Salmonella Typhimurium infection in 10 countries with 150 reported cases, predominantly affecting young children, has been linked to chocolate products produced by a large multinational company. Extensive withdrawals and recalls of multiple product lines have been undertaken. With Easter approaching, widespread product distribution and the vulnerability of the affected population, early and effective real-time sharing of microbiological and epidemiological information has been of critical importance in effectively managing this serious food-borne incident.

Nationwide outbreak of invasive listeriosis associated with consumption of meat products in health care facilities, Germany, 2014-2019.

OBJECTIVES: Invasive listeriosis is a severe foodborne infection caused by Listeria(L.)monocytogenes. The aim of this investigation was to verify and describe a molecular cluster of listeriosis patients and identify factors leading to this outbreak. METHODS: Whole genome sequencing and core genome multilocus sequence typing were used for subtyping L. monocytogenes isolates from listeriosis cases and food samples in Germany. Patient interviews and investigational tracing of foodstuffs offered in health-care facilities (HCF), where some of the cases occurred, were conducted. RESULTS: We identified a German-wide listeriosis outbreak with 39 genetically related cases occurring between 2014 and 2019. Three patients died as a result of listeriosis. After identification of HCF in different regions of Germany for at least 13 cases as places of exposure, investigational tracing of food supplies in six prioritized HCF revealed meat products from one company (X) as a commonality. Subsequently the outbreak strain was analysed in six isolates from ready-to-eat meat products and one isolate from the production environment of company X. No further Sigma1 cases were detected after recall of the meat products from the market and closure of company X (as of August 2020). CONCLUSIONS: Interdisciplinary efforts including whole genome sequencing, epidemiological investigations in patients and investigational tracing of foods were essential to identify the source of infections, and thereby prevent further illnesses and deaths. This outbreak underlines the vulnerability of hospitalized patients for foodborne diseases, such as listeriosis. Food producers and HCF should minimize the risk of microbiological hazards when producing, selecting and preparing food for patients.

Invasive pneumococcal disease in children under 16 years of age: Incomplete rebound in incidence after the maximum effect of PCV13 in 2012/13 in Germany.

OBJECTIVE: To identify a potential nadir of the impact of pneumococcal conjugate vaccination (PCV) in infancy on invasive pneumococcal diseases (IPD) in children under 16 in Germany. METHODS: Active surveillance on IPD based on two independent data sources with capture-recapture correction for underreporting. Annual incidence rates by age group, serotypes, site of infection, and relative incidence reduction compared to pre-vaccination period (1997-2001) at nadir and for the most recent season are reported. We calculated vaccine coverage at the age of 24 months using health insurance claims data. RESULTS: 96-97% of children had received at least two doses of PCV since 2009. The maximum impact on overall IPD incidence was achieved in 2012/13 (-48% [95% CI: -55%; -39%]) with a rebound to -26% [95% CI: -36%; -16%] in 2015/16. Non-PCV13 serotypes accounted for 84.1% of the IPD cases in 2015/16. The most frequent non-PCV serotypes in IPD in 2014/15 and 2015/16 were 10A, 24F, 15C, 12F, 38, 22F, 23B, and 15B. The impact at nadir was highest in children 0-1 years of age both in meningitis and non-meningitis cases, whereas the impact for other age groups was higher for meningitis cases. The rebound mainly pertained to non-meningitis cases. CONCLUSION: The maximum impact of pneumococcal conjugate vaccination has been attained and signs of a rebound are apparent. Sustained surveillance for IPD in children is warranted to assess whether these trends will continue. There may be a need for vaccines using antigens common to all serotypes.

Effectiveness of the 23-Valent Pneumococcal Polysaccharide Vaccine (PPV23) against Pneumococcal Disease in the Elderly: Systematic Review and Meta-Analysis.

BACKGROUND: Routine vaccination of elderly people against pneumococcal diseases is recommended in many countries. National guidelines differ, recommending either the 23-valent polysaccharide vaccine (PPV23), the 13-valent conjugate vaccine (PCV13) or both. Considering the ongoing debate on the effectiveness of PPV23, we performed a systematic literature review and meta-analysis of the vaccine efficacy/effectiveness (VE) of PPV23 against invasive pneumococcal disease (IPD) and pneumococcal pneumonia in adults aged ≥60 years living in industrialized countries. METHODS: We searched for pertinent clinical trials and observational studies in databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. We assessed the risk of bias of individual studies using the Cochrane Risk of Bias tool for randomized controlled trials and the Newcastle-Ottawa Scale for observational studies. We rated the overall quality of the evidence by GRADE criteria. We performed meta-analyses of studies grouped by outcome and study design using random-effects models. We applied a sensitivity analysis excluding studies with high risk of bias. RESULTS: We identified 17 eligible studies. Pooled VE against IPD (by any serotype) was 73% (95%CI: 10-92%) in four clinical trials, 45% (95%CI: 15-65%) in three cohort studies, and 59% (95%CI: 35-74%) in three case-control studies. After excluding studies with high risk of bias, pooled VE against pneumococcal pneumonia (by any serotype) was 64% (95%CI: 35-80%) in two clinical trials and 48% (95%CI: 25-63%) in two cohort studies. Higher VE estimates in trials (follow-up ~2.5 years) than in observational studies (follow-up ~5 years) may indicate waning protection. Unlike previous meta-analyses, we excluded two trials with high risk of bias regarding the outcome pneumococcal pneumonia, because diagnosis was based on serologic methods with insufficient specificity. CONCLUSIONS: Our meta-analysis revealed significant VE of PPV23 against both IPD and pneumococcal pneumonia by any serotype in the elderly, comparable to the efficacy of PCV13 against vaccine-serotype disease in a recent clinical trial in elderly people. Due to its broader serotype coverage and the decrease of PCV13 serotypes among adults resulting from routine infant immunization with PCV13, PPV23 continues to play an important role for protecting adults against IPD and pneumococcal pneumonia.

Effectiveness, immunogenicity and safety of 23-valent pneumococcal polysaccharide vaccine revaccinations in the elderly: a systematic review.

BACKGROUND: In many industrialized countries routine vaccination with the 23-valent pneumococcal polysaccharide vaccine (PPSV-23) is recommended to prevent pneumococcal disease in the elderly. However, vaccine-induced immunity wanes after a few years, and there are controversies around revaccination with PPSV-23. Here, we systematically assessed the effectiveness and safety of PPSV-23 revaccination. METHOD: We conducted a systematic literature review in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials from inception to June 2015. We included all study types that compared effectiveness, immunogenicity and/or safety of PPSV-23 as a primary vs. a revaccination dose in persons aged 50 years and older. With respect to immunogenicity, we calculated the ratio of geometric mean antibody concentrations and opsonophagocytic indexes at identical time-points after primary and revaccination. Additionally, we compared rates and severity of adverse events (AEs) after primary and revaccination. RESULTS: We included 14 observational studies. 10 studies had a prospective design and analysed data on (i) the same individuals after a first and a second dose of PPSV-23 given 1 to 10 years later (n = 5) or (ii) two groups consisting of participants receiving PPSV-23 who were either vaccine-naïve or had received a first PPSV-23 dose 3 to 13 years earlier (n = 5). Three studies used electronic data bases to compare AEs after primary vs. revaccination doses of PPSV-23 after 1 to 10 years and one study had a cross-sectional design. Number of participants in the non-register-based and register-based studies ranged from 29 to 1414 and 360 to 316,000, respectively. 11 out of 14 included studies were at high risk of bias, three studies had an unclear risk of bias. None of the studies reported data on clinical effectiveness. Immunogenicity studies revealed that during the first two months antibody levels tended to be lower after revaccination as compared to primary vaccination. Thereafter, no obvious differences in antibody levels were observed. Compared to primary vaccination, revaccination was associated with an increased risk of local and systemic AEs, which, however, were usually mild and self-limiting. The risk and severity of AEs appeared to decrease with longer intervals between primary and revaccination. CONCLUSION: Data comparing the effectiveness of primary vs. revaccination with PPSV-23 are still lacking, because there are no studies with clinical endpoints. Data from observational studies indicates that revaccination with PPSV-23 is likely to induce long-term antibody levels that are comparable to those after primary vaccination. Given the high disease burden and the waning of vaccine-induced immunity, revaccination with PPSV-23 could be considered in the elderly. The increased risk of local and systemic AEs can likely be mitigated when giving revaccination at least five years after the primary dose. Adequately powered randomized controlled trials using clinical endpoints are urgently needed.

Effectiveness of Pneumococcal Conjugate Vaccines (PCV7 and PCV13) against Invasive Pneumococcal Disease among Children under Two Years of Age in Germany.

BACKGROUND: In this study we calculate the effectiveness of pneumococcal conjugate vaccines (PCV) against invasive pneumococcal disease (IPD) among children under the age of two years using the indirect cohort method. We also discuss the timeliness of vaccination and the residual cases of vaccine type IPD. METHODS AND FINDINGS: From July 2006 until June 2015, 921 IPD cases were reported and for 618 children (67.1%), the vaccination status at the time of infection could be accurately determined. Of these, 379 (61.3%) were vaccinated and 239 (38.7%) were not vaccinated. The adjusted vaccine effectiveness (VE) of PCV7 for all included serotypes + 6A was 80% (95% CI: 63-89) for at least one dose, 97% (89-100) after three primary doses (post primary) and 95% (57-100) post booster. The adjusted overall VE of PCV13 was 86% (74-93) for at least one dose, 85% (62-94) post primary and 91% (61-99) post booster. For the additional serotypes included in PCV13, the adjusted VE was 82% (66-91), 80% (46-93) and 90% (54-98) respectively. The serotype specific VE for at least one dose was high for serotypes 1 (83%; 15-97), 3 (74%; 2-93), 7F (84%; 18-98) and 19A (77%; 47-90). Only 39.5% of children with IPD obtained their first dose of PCV7 according to schedule (2nd dose: 32.9%, 3rd dose: 22.0%, booster dose: 63.6%). For children vaccinated with PCV13 values were slightly better: 43.8%, 33.5%, 26.3% and 74.3% respectively. Among 90 residual cases with PCV7 serotypes, 73 (81.1%) were in unvaccinated children, and 15 (16.7%) in children who had not obtained the number of doses recommended for their age, and only two (2.2%) in children vaccinated according to age. Of 82 cases with PCV13 serotypes occurring after the switch from PCV7 to PCV13, 56 (68.3%) were not vaccinated, 22 (26.8%) were incompletely vaccinated, and four (4.9%) were vaccinated according to age. CONCLUSIONS: Our data show a high effectiveness of pneumococcal conjugate vaccination in Germany. However, the administration of vaccine doses among children with IPD is often delayed, resulting in many vaccine type cases in non- or incompletely-vaccinated children. Whether the recently-implemented change to a 2+1 schedule will improve the timeliness of vaccination should be subject to careful monitoring.

[Polio vaccination and stool screening in German reception centers for asylum seekers, November 2013-January 2014 : What was implemented?]. / Polioimpfung und Stuhlscreening in deutschen Erstaufnahmeeinrichtungen für Asylsuchende, November 2013-Januar 2014 : Was wurde umgesetzt?

BACKGROUND: Following the polio outbreak in Syria and the rising number of Syrian asylum seekers in Germany in 2013, the Robert Koch Institute recommended - within the context of existing vaccination recommendations for asylum seekers - on 01/11/2013 to prioritize polio vaccination of Syrian asylum seekers and stool screening in a target group of Syrian asylum seekers aged less than three years. OBJECTIVES: The article evaluates the implementation of this recommendation in German asylum seeker reception centres (RC) to gain further knowledge on the vaccination practices in RCs and to identify opportunities for improving future recommendations. METHODS: The electronic questionnaire was sent by email to all German RCs, asking for general information on the RC, existing vaccination efforts, the main obstacles for implementation of the recommendations, the number of incoming and vaccinated asylum seekers, and asylum seekers screened for poliovirus in the period from 01/11/2013 to 31/01/2014. The RCs rated the feasibility of the recommendation and the provided multilingual information material. RESULTS AND CONCLUSION: All of the 20 identified RCs responded. During the study period, 33.874 asylum seekers arrived in the RCs. Of those with available information about possession of a vaccination record, on average 1.6 % did have one. All RCs offered timely vaccination to Syrian asylum seekers younger than three years. In this target group, eight RC achieved vaccination coverages of ≥ 80 %. Stool screening coverage was ≥ 80 % in five of 19 RCs. Eleven RCs rated the recommendation as very well/well implementable. Staff shortages and language barriers were mentioned as the main implementation obstacles. Similar future recommendations for asylum seekers in RCs should be accompanied by informational material in additional languages. Staff shortages hampering implementation could be overcome through collaborations with non-governmental organizations.

Hepatitis B immune status in adolescents vaccinated during infancy: A retrospective cohort study from a pediatric practice in Germany.

In Germany, vaccination of infants against hepatitis B is recommended since 1995. However, data on long-term immunity is sparse and the necessity of a booster dose remains uncertain. Aims of this study were to assess the long-term persistence of antibodies to the hepatitis B surface antigen (anti-HBs) after immunization during infancy and the effect of a subsequent hepatitis B booster vaccination during adolescence on anti-HBs levels. Patients from a private pediatric practice who had received a full vaccination course of hepatitis B as infants and who were quantitatively tested for anti-HBs during adolescence (pre-booster levels) were included. In those participants who received a hepatitis B booster, post-booster anti-HBs levels were measured. Univariate analyses were conducted to determine factors associated with pre- and post-booster anti-HBs levels, respectively. 106 participants (53% male) were included in the study. At an average of 13.7 y after primary vaccination, 14% of participants had an anti-HBs level of ≥100 IU/l, while 46% were at 10-99 IU/l and 40% had anti-HBs levels of <10 IU/l. In total, 34 received a booster vaccination. Of those, 97% (33/34) had post-booster anti-HBs levels ≥ 100 IU/l, which were independent from pre-booster levels. No other patient characteristics were associated with pre-booster or post-booster anti-HBs≥ 100 IU/l. Although almost half of study participants showed low anti-HBs levels at follow-up, robust responses to booster vaccination suggest that adolescents who received the full vaccination course during infancy are still protected against hepatitis B infection.

Incidence of invasive pneumococcal disease in 5-15 year old children with and without comorbidities in Germany after the introduction of PCV13: Implications for vaccinating children with comorbidities.

OBJECTIVE: To describe the burden of suffering from IPD in children aged 5-15 years with and without comorbidities up to 5 years after the introduction of PCV13 in Germany and to identify the potential benefit for PCV13 and PPV23 vaccination. METHODS: The surveillance of IPD for children <16 years was based on two independently reporting sources: active surveillance in pediatric hospitals and a laboratory-based sentinel surveillance system. CASE DEFINITION: IPD with cultural detection of pneumococci at a physiologically sterile site in children from 2010 to 2014 in Germany. Incidence was estimated by capture-recapture analysis with stratification by absence/presence of comorbidities. Coverage of the observed serotypes by different vaccines was assessed. RESULTS: 142 (Capture recapture-corrected: 437) cases were reported: 72.5% were healthy children and 27.5% had a comorbidity. The incidence of IPD related to children with comorbidities was 0.2 per 100,000. One third of these cases had serotypes not included in either vaccine. The remaining cases might benefit from pneumococcal vaccination but one third of all cases was not vaccinated. The additional potential benefit of PPV23 compared to PCV13 with respect to coverage was 10%. CONCLUSION: The incidence of IPD in children with comorbidities in Germany is low. Pneumococcal vaccination uptake in children with comorbidities should be increased, although only about two-thirds of the cases might be preventable by presently available vaccines.

Effects of Infant Pneumococcal Conjugate Vaccination on Serotype Distribution in Invasive Pneumococcal Disease among Children and Adults in Germany.

This study describes the effects of the introduction of universal infant pneumococcal conjugate vaccination in 2006 on invasive pneumococcal disease (IPD) among children and adults in Germany with a focus on the dynamics of serotype distribution in vaccinated and non-vaccinated age groups. Over a period of 22 years (1992-2014), microbiological diagnostic laboratories from all over Germany have been sending isolates of IPD cases to the German National Reference Center for Streptococci on a voluntary basis. Streptococcus pneumoniae isolates were serotyped using Neufeld's Quellung method. Among children <16 years, the proportion of PCV7 serotypes among isolates from IPD cases decreased from 61.8% before vaccination (1997-2006) to 23.5% in the early vaccination period (2007-2010; p = 1.30E-72) and sank further to 5.2% in the late vaccination period (2010-2014; p = 4.59E-25). Similar reductions were seen for the separate age groups <2 years, 2-4 years and 5-15 years. Among adults, the proportion of PCV7 serotypes decreased from 43.4% in the pre-vaccination period (1992-2006) to 24.7% (p = 3.78E-88) in the early vaccination period and 8.2% (p = 5.97E-161) in the late vaccination period. Both among children and among adults, the non-PCV7 serotypes 1, 3, 7F and 19A significantly increased in the early vaccination period. After the switch from PCV7 to PVC10/PCV13 for infant vaccination in 2010, serotypes 1, 6A and 7F significantly decreased. A decrease in serotype 19A was only observed in 2013-2014, as compared to 2010-2011 (children p = 4.16E-04, adults p = 6.98E-06). Among adults, serotype 3, which strongly increased in the early vaccination period (p = 4.44E-15), remained at a constant proportion in the late vaccination period. The proportion of non-PCV13 vaccine serotypes increased over the whole vaccination period, with serotypes 10A, 12F, 23B, 24F and 38 most significantly increasing among children and serotypes 6C, 12F, 15A, 22F and 23B increasing among adults. Eight years of childhood pneumococcal conjugate vaccination have had a strong effect on the pneumococcal population in Germany, both among the target group for vaccination as well as among older children and adults.

Seroincidence of human infections with nontyphoid Salmonella compared with data from public health surveillance and food animals in 13 European countries.

We developed a model that enabled a back-calculation of the annual salmonellosis seroincidence from measurements of Salmonella antibodies and applied this model to 9677 serum samples collected from populations in 13 European countries. We found a 10-fold difference in the seroincidence, which was lowest in Sweden (0.06 infections per person-year), Finland (0.07), and Denmark (0.08) and highest in Spain (0.61), followed by Poland (0.55). These numbers were not correlated with the reported national incidence of Salmonella infections in humans but were correlated with prevalence data of Salmonella in laying hens (P < .001), broilers (P < .001), and slaughter pigs (P = .03). Seroincidence also correlated with Swedish data on the country-specific risk of travel-associated Salmonella infections (P = .001). Estimates based on seroepidemiological methods are well suited to measure the force of transmission of Salmonella to human populations, in particular relevant for assessments where data include notifications from areas, states or countries with diverse characteristics of the Salmonella surveillance.

Serological follow-up after non-typhoid salmonella infection in humans using a mixed lipopolysaccharide ELISA.

In industrialized countries, non-typhoid salmonella are a frequent cause of bacterial gastroenteritis. Diagnosis is usually made by stool culture, which is labour-intensive and time-consuming. Sensitivity depends on handling of stool samples and delay from illness onset to sampling. We developed an indirect mixed enzyme-linked immunosorbent assay (ELISA) for the detection of human serum antibodies against lipopolysaccharide antigens of the two predominant serovars, Salmonella serovar Enteritidis (S. Enteritidis) and S. Typhimurium. We measured IgA, IgM and IgG in 964 sera from 302 patients with stool culture-confirmed acute salmonella gastroenteritis, in 300 sera from healthy blood donors, and in 147 sera from patients with antibodies against other bacteria. Patient sera were collected within 1 month and approximately 3, 6, and 12 months after illness onset. For sera collected ≤ 30 days of onset, sensitivity of the ELISA was 92% for S. Enteritidis and 86% for S. Typhimurium, with a specificity of 95% for both serovars. The mixed ELISA is a useful additional tool for the diagnosis of acute salmonella gastroenteritis. It allows rapid analysis of multiple samples, thus can be used for sero-epidemiological studies of large population-based serum collections in order to estimate the population incidence of salmonella infections. Another application is aetiological diagnostics in patients with suspected post-infectious complications such as reactive arthritis, even when faecal shedding of salmonella has ceased.

MRSA transmission on a neonatal intensive care unit: epidemiological and genome-based phylogenetic analyses.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) may cause prolonged outbreaks of infections in neonatal intensive care units (NICUs). While the specific factors favouring MRSA spread on neonatal wards are not well understood, colonized infants, their relatives, or health-care workers may all be sources for MRSA transmission. Whole-genome sequencing may provide a new tool for elucidating transmission pathways of MRSA at a local scale. METHODS AND FINDINGS: We applied whole-genome sequencing to trace MRSA spread in a NICU and performed a case-control study to identify risk factors for MRSA transmission. MRSA genomes had accumulated sequence variation sufficiently fast to reflect epidemiological linkage among individual patients, between infants and their mothers, and between infants and staff members, such that the relevance of individual nurses' nasal MRSA colonization for prolonged transmission could be evaluated. In addition to confirming previously reported risk factors, we identified an increased risk of transmission from infants with as yet unknown MRSA colonisation, in contrast to known MRSA-positive infants. CONCLUSIONS: The integration of epidemiological (temporal, spatial) and genomic data enabled the phylogenetic testing of several hypotheses on specific MRSA transmission routes within a neonatal intensive-care unit. The pronounced risk of transmission emanating from undetected MRSA carriers suggested that increasing the frequency or speed of microbiological diagnostics could help to reduce transmission of MRSA.

Barriers to pandemic influenza vaccination and uptake of seasonal influenza vaccine in the post-pandemic season in Germany.

BACKGROUND: In Germany, annual vaccination against seasonal influenza is recommended for certain target groups (e.g. persons aged ≥60 years, chronically ill persons, healthcare workers (HCW)). In season 2009/10, vaccination against pandemic influenza A(H1N1)pdm09, which was controversially discussed in the public, was recommended for the whole population. The objectives of this study were to assess vaccination coverage for seasonal (seasons 2008/09-2010/11) and pandemic influenza (season 2009/10), to identify predictors of and barriers to pandemic vaccine uptake and whether the controversial discussions on pandemic vaccination has had a negative impact on seasonal influenza vaccine uptake in Germany. METHODS: We analysed data from the 'German Health Update' (GEDA10) telephone survey (n=22,050) and a smaller GEDA10-follow-up survey (n=2,493), which were both representative of the general population aged ≥18 years living in Germany. RESULTS: Overall only 8.8% of the adult population in Germany received a vaccination against pandemic influenza. High socioeconomic status, having received a seasonal influenza shot in the previous season, and belonging to a target group for seasonal influenza vaccination were independently associated with the uptake of pandemic vaccines. The main reasons for not receiving a pandemic vaccination were 'fear of side effects' and the opinion that 'vaccination was not necessary'. Seasonal influenza vaccine uptake in the pre-pandemic season 2008/09 was 52.8% among persons aged ≥60 years; 30.5% among HCW, and 43.3% among chronically ill persons. A decrease in vaccination coverage was observed across all target groups in the first post-pandemic season 2010/11 (50.6%, 25.8%, and 41.0% vaccination coverage, respectively). CONCLUSIONS: Seasonal influenza vaccination coverage in Germany remains in all target groups below 75%, which is a declared goal of the European Union. Our results suggest that controversial public discussions about safety and the benefits of pandemic influenza vaccination may have contributed to both a very low uptake of pandemic vaccines and a decreased uptake of seasonal influenza vaccines in the first post-pandemic season. In the upcoming years, the uptake of seasonal influenza vaccines should be carefully monitored in all target groups to identify if this trend continues and to guide public health authorities in developing more effective vaccination and communication strategies for seasonal influenza vaccination.

Serological cross-sectional studies on salmonella incidence in eight European countries: no correlation with incidence of reported cases.

BACKGROUND: Published incidence rates of human salmonella infections are mostly based on numbers of stool culture-confirmed cases reported to public health surveillance. These cases constitute only a small fraction of all cases occurring in the community. The extent of underascertainment is influenced by health care seeking behaviour and sensitivity of surveillance systems, so that reported incidence rates from different countries are not comparable. We performed serological cross-sectional studies to compare infection risks in eight European countries independent of underascertainment. METHODS: A total of 6,393 sera from adults in Denmark, Finland, France, Italy, Poland, Romania, Sweden, and The Netherlands were analysed, mostly from existing serum banks collected in the years 2003 to 2008. Immunoglobulin A (IgA), IgM, and IgG against salmonella lipopolysaccharides were measured by in-house mixed ELISA. We converted antibody concentrations to estimates of infection incidence ('sero-incidence') using a Bayesian backcalculation model, based on previously studied antibody decay profiles in persons with culture-confirmed salmonella infections. We compared sero-incidence with incidence of cases reported through routine public health surveillance and with published incidence estimates derived from infection risks in Swedish travellers to those countries. RESULTS: Sero-incidence of salmonella infections ranged from 56 (95% credible interval 8-151) infections per 1,000 person-years in Finland to 547 (343-813) in Poland. Depending on country, sero-incidence was approximately 100 to 2,000 times higher than incidence of culture-confirmed cases reported through routine surveillance, with a trend for an inverse correlation. Sero-incidence was significantly correlated with incidence estimated from infection risks in Swedish travellers. CONCLUSIONS: Sero-incidence estimation is a new method to estimate and compare the incidence of salmonella infections in human populations independent of surveillance artefacts. Our results confirm that comparison of reported incidence between countries can be grossly misleading, even within the European Union. Because sero-incidence includes asymptomatic infections, it is not a direct measure of burden of illness. But, pending further validation of this novel method, it may be a promising and cost-effective way to assess infection risks and to evaluate the effectiveness of salmonella control programmes across countries or over time.

Detection of antibodies to Campylobacter in humans using enzyme-linked immunosorbent assays: a review of the literature.

Campylobacteriosis is the most common cause of bacterial foodborne illness in the European Union and the United States. Infection with Campylobacter spp. is frequently associated with different sequelae including neuropathies and reactive arthritis. Diagnosis is mainly by bacterial culturing which is time consuming, expensive, and not well suited for diagnosing sequelae or identifying infections from stool samples with nonviable bacteria. Serologic assays, in particular ELISAs, are well suited for this purpose, but, at present, there is no international consensus on antibody assays for human campylobacteriosis. In an extensive literature review, 19 studies validating such assays were identified of which 13 were more than 10 years old. We conclude that the best validated of these assays are developed and used in-house for research purposes rather than for routine diagnostics. Considering the burden of disease and potential long-term severity of Campylobacter infections, developing a standardized, commercially available antibody assay could be of great benefit for diagnostic and surveillance purposes worldwide.

Four years of universal pneumococcal conjugate infant vaccination in Germany: impact on incidence of invasive pneumococcal disease and serotype distribution in children.

INTRODUCTION: Vaccination with pneumococcal conjugate vaccine (PCV) for all children <2 years was recommended in Germany in July 2006. Initially PCV7 was exclusively used; PCV10 became available from April 2009 and PCV7 was replaced by PCV13 in December 2009. OBJECTIVE: To compare the incidence and serotype distribution of invasive pneumococcal disease (IPD) for pneumococcal meningitis and non-meningitis IPD in children from 2007 to 2010 with reference to the pre-vaccination period from 1997 to 2001. METHODS: Nationwide surveillance of IPD for children <16 years in Germany was based on two independent reporting sources: active surveillance in paediatric hospitals and passive web-based surveillance through microbiological laboratories. Serotyping was performed using the Neufeld Quellung reaction. CASE DEFINITION: isolation of Streptococcus pneumoniae from a normally sterile body site. IPD incidence was estimated by capture-recapture analysis. Rate ratios comparing post- to pre-vaccination incidence were calculated as well as PCV7 and non-PCV7 serotype specific incidences. RESULTS: While PCV7 incidence decreased by 88% (95%CI: 83 to 91) in children <16 years both in pneumococcal meningitis and non-meningitis IPD, an increase in Non-PCV7 serotypes was observed which was more pronounced in non-meningitis cases (168%; 95%CI: 140-257) than in pneumoccocal meningitis (65%; 95%CI: 23-123). The changes in incidence after four years were: <16 years: -35% (95%CI: -49 to -19), <2 years: -46% (95%CI: -61 to -27) for pneumococcal meningitis and+11% (95%CI: -4 to +29) and -26% (95%CI: -41 to -7) for non-meningitis IPD respectively. CONCLUSION: Infant PCV7 vaccination in Germany prompted a decrease in the incidence of pneumococcal meningitis similar to that observed in England/Wales. In non-meningitis IPD the decrease was smaller and confined to the age group <2 years with no change or an increase in incidence in other age groups pointing to potential ascertainment bias due to increased blood-culturing.