Andreas Jansen

Leptospirosis in Germany, 1962–2003

Epidemiologic trends of human leptospirosis in Germany were investigated by analyzing national surveillance data from 1962 to 2003 and by conducting a questionnaire-based survey from 1997 to 2000. After a steady decrease of leptospirosis incidence from 1962 to 1997, surveillance data indicate an increase in disease incidence to 0.06 per 100,000 (1998–2003). Of 102 laboratory-confirmed cases in humans from 1997 to 2000, 30% were related to occupational exposures. Recreational exposures were reported in 30% (including traveling abroad in 16%), whereas residential exposure accounted for 37% of the cases. Direct contact with animals, mostly rats and dogs, was observed in 31% of the cases. We conclude that recent changes in transmission patterns of leptospirosis, partially caused by an expanding rat population and the resurgence of canine leptospirosis, may facilitate the spread of the disease in temperate countries like Germany. Preventive measures should be adapted to the changing epidemiology of leptospirosis.

Major outbreak of hepatitis A associated with orange juice among tourists, Egypt, 2004.

In 2004, a major outbreak of hepatitis A among tourists returning from Egypt involved 351 case-patients from 9 European countries who were infected with a single strain (genotype 1b). The case-control study identified orange juice as the most likely infection vehicle. Vaccination against hepatitis A virus is strongly recommended before travel to disease-endemic areas.

Leptospirosis in Urban Wild Boars, Berlin, Germany

We found antibodies to leptospires in 25 (18%) of 141 wild boars from Berlin (95% confidence interval 12–25). Seropositivity was associated with chronic interstitial nephritis (odds ratio 10.5; p = 0.01), and leptospires were detected in kidney tissues. Wild boars represent a potential source for human leptospirosis in urban environments.

Changing Epidemiology of Human Brucellosis, Germany, 1962-2005

This endemic occupational disease has become a foodborne and travel-associated zoonosis primarily affecting Turkish immigrants.

The Immune Reconstitution Inflammatory Syndrome in Whipple Disease: A Cohort Study

BACKGROUND Whipple disease, which is caused by infection with Tropheryma whipplei, can be treated effectively with antimicrobials. Occasionally, inflammation reappears after initial improvement; this is often interpreted as refractory or recurrent disease. However, polymerase chain reaction for T. whipplei in tissue is sometimes negative during reinflammation, indicating absence of vital bacteria, and this reinflammation does not respond to antimicrobials but does respond to steroids. OBJECTIVE To demonstrate that the immune reconstitution inflammatory syndrome (IRIS) occurs in patients treated for Whipple disease. DESIGN Cohort study. (International Standard Randomised Controlled Trial Number Register registration number: ISRCTN45658456) SETTING 2 academic medical centers in Germany. METHODS 142 patients treated for Whipple disease out of a cohort of 187 were observed for reappearance of inflammatory signs after effective antibiotic therapy. Definitions of IRIS in HIV infection, tuberculosis, and leprosy were adapted for application to Whipple disease. RESULTS On the basis of study definitions, IRIS was diagnosed in 15 of 142 patients. Symptoms included fever, arthritis, pleurisy, erythema nodosum, inflammatory orbitopathy, small-bowel perforation, and a hypothalamic syndrome. Two patients died. There was a positive correlation with previous immunosuppressive treatment and a negative correlation with previous diarrhea and weight loss. LIMITATIONS The study was observational and thus has inherent weaknesses, such as incomplete and potentially selective data recording. CONCLUSION The immune reconstitution inflammatory syndrome was diagnosed in about 10% of patients with Whipple disease in the study cohort; the outcome varied from mild to fatal. Patients who had had previous immunosuppressive therapy were at particular risk. An immune reconstitution syndrome should be considered in patients with Whipple disease in whom inflammatory symptoms recur after effective treatment. Early diagnosis and treatment with steroids may be beneficial; prospective studies are needed. PRIMARY FUNDING SOURCE European Commission and Deutsche Forschungsgemeinschaft.

Ethics of mandatory vaccination for healthcare workers

Healthcare workers (HCWs) are at increased risk of contracting infections at work and further transmitting them to colleagues and patients. Immune HCWs would be protected themselves and act as a barrier against the spread of infections and maintain healthcare delivery during outbreaks, but vaccine uptake rates in HCWs have often been low. In order to achieve adequate immunisation rates in HCWs, mandatory vaccination policies are occasionally implemented by healthcare authorities, but such policies have raised considerable controversy. Here we review the background of this debate, analyse arguments for and against mandatory vaccination policies, and consider the principles and virtues of clinical, professional, institutional and public health ethics. We conclude that there is a moral imperative for HCWs to be immune and for healthcare institutions to ensure HCW vaccination, in particular for those working in settings with high-risk groups of patients. If voluntary uptake of vaccination by HCWs is not optimal, patients’ welfare, public health and also the HCW’s own health interests should outweigh concerns about individual autonomy: fair mandatory vaccination policies for HCWs might be acceptable. Differences in diseases, patient and HCW groups at risk and available vaccines should be taken into consideration when adopting the optimal policy.

Epidemiology of Trichinellosis in Germany, 1996–2006

The epidemiology of trichinellosis in Germany was investigated by analyzing national surveillance data from 1996-2006. During this period, 95 laboratory-confirmed infections and 12 outbreaks were reported. The highest mean annual incidence was found in immigrants from southeast European countries (0.3 cases/100,000 vs. 0.01 cases/100,000 in the German population) with an incidence rate ratio of 26.0 (95% confidence interval 11.6-51.8). The predominant clinical symptom was muscle pain in 79 patients (83%). Mean diagnostic delay was 49 days. Among patients with reported source of infection (85%; n = 81), the consumption of pork (mostly originating from endemic countries) represented the most frequent exposure (93%; n = 75). In addition, trichinellosis cases were associated with both indigenous (n = 1) and imported (n = 5) wild boar meat. Although domestic pigs in Germany are practically free from Trichinella spp., the parasite was found in German wild animals such as wild boars, foxes, and racoon dogs. We conclude that trichinellosis still remains a public health issue in Germany, especially among individuals with a migrational background. Immigrants from endemic countries need to be educated about the risks of consuming raw or inadequately cooked pork and wild boar products from their homeland. In addition, German healthcare providers need to be aware of trichinellosis, especially in areas with a large immigrant population.

Evidence-based decision-making in infectious diseases epidemiology, prevention and control: matching research questions to study designs and quality appraisal tools.

BackgroundThe Project on a Framework for Rating Evidence in Public Health (PRECEPT) was initiated and is being funded by the European Centre for Disease Prevention and Control (ECDC) to define a methodology for evaluating and grading evidence and strength of recommendations in the field of public health, with emphasis on infectious disease epidemiology, prevention and control. One of the first steps was to review existing quality appraisal tools (QATs) for individual research studies of various designs relevant to this area, using a question-based approach.MethodsThrough team discussions and expert consultations, we identified 20 relevant types of public health questions, which were grouped into six domains, i.e. characteristics of the pathogen, burden of disease, diagnosis, risk factors, intervention, and implementation of intervention. Previously published systematic reviews were used and supplemented by expert consultation to identify suitable QATs. Finally, a matrix was constructed for matching questions to study designs suitable to address them and respective QATs. Key features of each of the included QATs were then analyzed, in particular in respect to its intended use, types of questions and answers, presence/absence of a quality score, and if a validation was performed.ResultsIn total we identified 21 QATs and 26 study designs, and matched them. Four QATs were suitable for experimental quantitative study designs, eleven for observational quantitative studies, two for qualitative studies, three for economic studies, one for diagnostic test accuracy studies, and one for animal studies. Included QATs consisted of six to 28 items. Six of the QATs had a summary quality score. Fourteen QATs had undergone at least one validation procedure.ConclusionsThe results of this methodological study can be used as an inventory of potentially relevant questions, appropriate study designs and QATs for researchers and authorities engaged with evidence-based decision-making in infectious disease epidemiology, prevention and control.

The role and utilisation of public health evaluations in Europe: a case study of national hand hygiene campaigns

BackgroundEvaluations are essential to judge the success of public health programmes. In Europe, the proportion of public health programmes that undergo evaluation remains unclear. The European Centre for Disease Prevention and Control sought to determine the frequency of evaluations amongst European national public health programmes by using national hand hygiene campaigns as an example of intervention.MethodsA cohort of all national hand hygiene campaigns initiated between 2000 and 2012 was utilised for the analysis. The aim was to collect information about evaluations of hand hygiene campaigns and their frequency. The survey was sent to nominated contact points for healthcare-associated infection surveillance in European Union and European Economic Area Member States.ResultsThirty-six hand hygiene campaigns in 20 countries were performed between 2000 and 2012. Of these, 50% had undergone an evaluation and 55% of those utilised the WHO hand hygiene intervention self-assessment tool. Evaluations utilised a variety of methodologies and indicators in assessing changes in hand hygiene behaviours pre and post intervention. Of the 50% of campaigns that were not evaluated, two thirds reported that both human and financial resource constraints posed significant barriers for the evaluation.ConclusionThe study identified an upward trend in the number of hand hygiene campaigns implemented in Europe. It is likely that the availability of the internationally-accepted evaluation methodology developed by the WHO contributed to the evaluation of more hand hygiene campaigns in Europe. Despite this rise, hand hygiene campaigns appear to be under-evaluated. The development of simple, programme-specific, standardised guidelines, evaluation indicators and other evidence-based public health materials could help promote evaluations across all areas of public health.

Antibodies against Rickettsia spp. in Hunters, Germany

To the Editor: A number of emerging Rickettsia species have been recently described (1). One of these, R. helvetica, was first isolated in Switzerland in 1979 and was implicated in perimyocarditis and nonspecific febrile disease in humans (2–5). PCR showed its prevalence in 1,187 Ixodes ricinus ticks in southern Germany to be 8.9% (6). This finding raises the question whether autochthonous transmission of rickettsiae to humans may occur in Germany. To help answer this question, we conducted a cross-sectional study of the presence of antibodies against Rickettsia spp. in a population in Germany presumably exposed to ticks. On February 4–5, 2006, we used convenience sampling to enroll 286 hunters at a national hunting fair in Dortmund, Germany. All study participants gave written, informed consent. The Ethics Committee of the Charite approved the study. Every participant completed a standardized questionnaire. Serum samples were collected from all hunters and analyzed by immunofluorescence assay for 9 Rickettsia species (R. conorii, R. slovaca, R. helvetica, R. massiliae, R. mongolitimonae, R. israelensis, R. aeschlimannii, R. felis, and R. typhi) as described previously (7). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by using SPSS software version 14 (SPSS, Inc., Chicago, IL, USA). We considered p<0.05 to be significant. Of the 286 hunters, 252 (88.1%) were male; median age was 46 years (range 17–79 years). Positive antibody titers (immunoglobulin [Ig] G, IgM, or both) against any Rickettsia spp. were found for 26 (9.1%) hunters (95% CI 6.2–13.0). Antibodies against different Rickettsia spp. were found for 18 hunters; species-specific antibodies against R. helvetica were found for 2 hunters and against R. aeschlimannii for 6 (Table). Seropositive and seronegative hunters did not differ significantly with respect to sex, age, and total years of hunting. Neither hunting nor traveling in a foreign country within the past 5 years was significantly associated with seropositivity. Neither of the 2 hunters with R. helvetica–specific antibody titers had traveled outside Germany in the 5 years before the study, but 3 of the 6 hunters with specific titers against R. aeschlimannii had traveled and hunted in countries with unknown endemicity for R. aeschlimannii (Russia, Romania, Namibia). A total of 212 (74.1%) hunters had received at least 1 tick bite in the year before the study; median was 4 tick bites/year. Living in the southern parts of Germany (below 50°N) was significantly related to seropositivity (OR 4.1, 95% CI 1.3–12.3, p = 0.02). Although the 26 persons with positive serologic results for Rickettsia spp. reported arthralgia with higher frequency than did seronegative persons (50% vs. 37%, respectively), their reports of arthralgia and of other clinical signs did not differ significantly: temperature >38.5°C (8% vs. 2%), enlarged lymph nodes (12% vs. 9%). No seropositive hunter reported having had an eschar. Table Positive immunofluorescence assay results for antigens to 9 Rickettsia spp. in 26 hunters, Germany, 2006* This study provides data for Germany on the seroprevalence of Rickettsia spp. in persons highly exposed to ticks. Our results suggest that Rickettsia spp. are endemic to southern Germany and may cause autochthonous infections. Although most seropositive hunters exhibited reactivity to several rickettsial antigens, some had species-specific titers for R. helvetica. Six hunters exhibited specific reactivity to R. aeschlimannii. Serologic cross-reactions are frequently noted among spotted fever group rickettsiae, and 1 of the best indicators of species identity remains the geographic origin of the infection (7). Until now, R. aeschlimannii had not been detected in Germany or neighboring countries. We therefore suggest that the specific titers against R. aeschlimannii in our study population may be partly related to traveling or hunting abroad and that the observed seroprevalence for other rickettsial species is most likely caused by R. helvetica, or, alternatively, by R. monacensis, which was recently isolated from a tick in the English Garden in Munich (9). Cutoff titers for IgM and IgG were chosen to achieve a specificity >98%; sensitivity varied between different rickettsial antigens. However, if we assume a sensitivity of only 50% (with a prevalence of 9.1%), the positive predictive value of our test would still be 74%. In addition, a test with high specificity and low sensitivity underestimates the true seroprevalence; the proportion of seropositive hunters in our study group is likely higher. Although hunters with positive immunofluorescence assay results reported having had symptoms compatible with rickettsioses more frequently than did seronegative hunters, these differences were not significant. A similar situation has been noted for persons who were tested for antibodies against Borrelia burgdorferi and human granulocytic anaplasmosis; the findings may reflect the mild and poorly defined clinical picture that is typical for each of these diseases (10). To conclude, we report the presence of Rickettsia spp. antibodies in a high-risk group from Germany. Final proof that human rickettsiosis occurs in Germany, however, will require the isolation of the agent from patients.