Search

Background: Campylobacter is the most frequently reported cause of acute infectious diarrhea in Germany. Campylobacter outbreaks are rare events. However, their investigation provides useful information on risks of infection and unused prevention potentials., Methods: We analyzed the Hessian database for notifiable diseases for cases of campylobacteriosis reported from 2005 through 2011. For campylobacter outbreaks including five or more cases we prospectively obtained additional information from local public health authorities., Results: From 2005 through 2011, 29,473 cases of campylobacteriosis were reported in Hesse, Germany (approx. 6 million inhabitants), yielding an annual incidence ranging from 53.4 to 81.4 cases per 100,000 inhabitants. Only 236 cases were part of 16 outbreaks with five or more cases. Among these, six outbreaks occurred among groups traveling outside Germany, four were associated with the consumption of raw milk. For eight outbreaks consumption of poultry was considered a probable or - based on the frequent consumption of poultry during group travel - possible vehicle of infection. Two of the raw-milk associated outbreaks were reported among two groups who visited the same farm within 18 days. Five of 14 members of several families and 77 of 117 students fell sick. The local public health authority was only informed when both groups had visited the farm., Conclusion: The reported outbreaks can be attributed to known risk factors for campylobacteriosis - consumption of raw milk and poultry and international travel. This underlines that prevention possibilities are insufficiently used. These include avoiding the consumption of unpasteurized milk and milk products, the hygienically correct handling of raw poultry and timely identification and notification of outbreaks to public health authorities., (© Georg Thieme Verlag KG Stuttgart · New York.)

During the recent outbreak of Shiga toxin-producing Escherichia coli (STEC) O104:H4 in Germany most cases notified in the State of Hesse (6 million inhabitants) were linked to satellite clusters or had travelled to the outbreak area in northern Germany. Intensified surveillance was introduced to rapidly identify cases not linked to known clusters or cases and thus to obtain timely information on possible further contaminated vehicles distributed in Hesse, as well to describe the risk of secondary transmission among known cases. As of 2 August 2011* [corrected], 56 cases of haemolytic uraemic syndrome (HUS) including two fatal cases, and 124 cases of STEC gastroenteritis meeting the national case definitions have been reported in Hesse. Among the 55 HUS and 81 STEC gastroenteritis cases thatmet the outbreak case definition, one HUS case and eight STEC gastroenteritis cases may have acquired their infection through secondary transmission. They include six possible transmissions within the family, two possible nosocomial and one possible laboratory transmission. Our results do not suggest an increased transmissibility of the outbreak strain compared to what is already known about E. coli O157 and other STEC serotypes.

Background: In Germany, surveillance for infectious disease outbreaks is integrated into an electronic surveillance system. For 2007, the national surveillance database contains case-based information on 201,224 norovirus cases, three-quarters of which are linked to outbreaks. We evaluated the data quality of the national database in reflecting nosocomial norovirus outbreak (NNO) data available in 19 Hessian local public health authorities (LPHAs) and the influence of differences between LPHA's follow-up procedures for laboratory notifications of Norovirus positive stool samples on outbreak underascertainment., Methods: Data on NNO beginning in 2007 and notified to the 19 LPHAs were extracted from the national database, investigated regarding internal validity and compared to data collected from LPHAs for a study on NNO control. LPHAs were questioned whether they routinely contacted all persons for whom a laboratory diagnosis of norovirus infection was notified. The number of outbreaks per 1,000 hospital beds and the number of cases within NNOs for acute care and rehabilitation hospitals were compared between counties with and without complete follow-up., Results: The national database contained information on 155 NNOs, including 3,115 cases. Cases were missed in the national database in 58 (37%) of the outbreaks. Information on hospitalisation was incorrect for an estimated 47% of NNO cases. Information on county of infection was incorrect for 24% (199/820) of cases being forwarded between LPHAs for data entry. Reported NNO incidence and number of NNO cases in acute care hospitals was higher in counties with complete follow-up (incidence-rate ratio (IRR) 2.7, 95% CI 1.4-5.7, p-value 0.002 and IRR 2.1, 95% CI 1.9-2.4, p-value 0.001, respectively)., Conclusions: Many NNOs are not notified by hospitals and differences in LPHA procedures have an impact on the number of outbreaks captured in the surveillance system. Forwarding of case-by-case data on Norovirus outbreak cases from the local to the state and national level should not be required.

In November 2005, an outbreak of tularemia occurred among 39 participants in a hare hunt in Hesse, Germany. Previously reported tularemia outbreaks in Germany dated back to the 1950s. We conducted a retrospective cohort study among participants and investigated the environment to identify risk factors for infection. Ten participants had serologic evidence of acute Francisella tularensis infection; 1 other participant died before laboratory confirmation was obtained. Presence within 5 meters of the place where disemboweled hares were rinsed with a water hose was the risk factor most strongly associated with infection (risk ratio 22.1; 95% confidence interval 13.2-154.3). Swabs taken at the game chamber and water samples were PCR negative for F. tularensis. Eleven of 14 hare parts showed low-level concentrations of F. tularensis, compatible with cross-contamination. More than half of case-patients may have acquired infection through inhalation of aerosolized droplets containing F. tularensis generated during rinsing of infected hares.

For the next influenza season (winter 2009-10) the relative contributions to virus circulation and influenza-associated morbidity of the seasonal influenza viruses A(H3N2), A(H1N1) and B, and the new influenza A(H1N1)v are still unknown. We estimated the chances of seasonal influenza to circulate during the upcoming season using data of the German influenza sentinel scheme from 1992 to 2009. We calculated type and subtype-specific indices for past exposure and the corresponding morbidity indices for each season. For the upcoming season 2009-10 our model suggests that it is unlikely that influenza A(H3N2) will circulate with more than a low intensity, seasonal A(H1N1) with more than a low to moderate intensity, and influenza B with more than a low to median intensity. The probability of a competitive circulation of seasonal influenza A with the new A(H1N1)v is low, increasing the chance for the latter to dominate the next influenza season in Germany.

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 1 b). 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.

During an outbreak in a German day-care centre (DCC) caring for 100 children HAV vaccination was recommended for children, employees and household members of cases. A retrospective cohort study was done to evaluate vaccine uptake and identify possible risk factors for disease. Between 19 December 2004 and 30 January 2005 eight DCC children and seven household members fulfilled the case definition, i.e. had clinical hepatitis (14) or were diagnosed with asymptomatic HAV infection (1). Following the recommendation to vaccinate, given on 23 December 2004, 66.7% (46/69) of DCC children, 15.8% (29/184) of household members and 5/5 of employees were vaccinated, and three vaccinated children and two not vaccinated children fell ill. One of 11 children who received human normal immunoglobulin (HNIG) and four of 58 children who did not receive HNIG fell ill. In households in which the DCC child received HAV vaccine and/or HNIG, seven (5.6%) of 125 household members fulfilled the case definition. In households of non-immunised children none of the 59 household members fell ill. We conclude that, although most vaccinations were administered promptly, they may not have been timely enough to impact the course of the outbreak.

Applied infectious disease epidemiology/field epidemiology involves the application of epidemiologic methods to unexpected health problems when a rapid, on-site investigation is necessary for timely intervention. While field investigations of acute problems share the need of high methodological quality with prospectively planned studies, they may differ in several respects. In particular, because field investigations of ten start without a clear hypothesis, they may require the use of descriptive studies to generate a hypothesis before analytic studies are conducted. There also may be an immediate need to protect the population's health, pressure to intervene may conflict with the need to investigate and publicity may introduce bias. Outbreak investigations are paradigms of the use and methodology of applied infectious disease epidemiology/field epidemiology. The steps of an outbreak investigation include verification, confirming the diagnosis, developing a case definition and case finding, describing the data in terms of time, place and person, risk identification, formulating and testing of a hypothesis, planning for further studies, establishing control measures and communicating the findings.

From July to October 2001, 215 cases of aseptic meningitis occurred among the inhabitants of the German city of Kassel and neighbouring counties. A matched case-control study identified bathing in a public, nature-like pond during the beginning of the outbreak as a risk factor for disease [matched odds ratio (mOR) 44.8, 95% confidence interval (CI) 3.9-515.6]. Among bathers, patients with meningitis spent more time in the water (mOR 18.8, 95% CI 2.0-174.1) and swallowed water more frequently (mOR = 7.3, 95% CI 0.7-81.8). Of 30 cerebrospinal fluid samples tested, echovirus 30 was cultured from 16, and echovirus 13 from seven. An echovirus 30 sequence obtained from one pond water sample showed a 99% nucleotide and 100% amino-acid homology with patient isolates. This outbreak demonstrates the potential of nature-like swimming ponds to cause widespread community infection with substantial public health impact.

Background: This report describes a large international chocolate-associated Salmonella outbreak originating from Germany., Methods: We conducted epidemiologic investigations including a case-control study, and food safety investigations. Salmonella (S.) Oranienburg isolates were subtyped by the use of pulsed-field gel electrophoresis (PFGE)., Results: From 1 October 2001 through 24 March 2002, an estimated excess of 439 S. Oranienburg notifications was registered in Germany. Simultaneously, an increase in S. Oranienburg infections was noted in other European countries in the Enter-net surveillance network. In a multistate matched case-control study in Germany, daily consumption of chocolate (matched odds ratio [MOR]: 4.8; 95% confidence interval [CI]: 1.3-26.5), having shopped at a large chain of discount grocery stores (MOR: 4.2; CI: 1.2-23.0), and consumption of chocolate purchased there (MOR: 5.0; CI: 1.1-47.0) were associated with illness. Subsequently, two brands from the same company, one exclusively produced for that chain, tested positive for S. Oranienburg. In two other European countries and in Canada chocolate from company A was ascertained that also contained S. Oranienburg. Isolates from humans and from chocolates had indistinguishable PFGE profiles. No source or point of contamination was identified. Epidemiological identification of chocolate as a vehicle of infections required two months, and was facilitated by proxy measures., Conclusions: Despite the use of improved production technologies, the chocolate industry continues to carry a small risk of manufacturing Salmonella-containing products. Particularly in diffuse outbreak-settings, clear associations with surrogates of exposure should suffice to trigger public health action. Networks such as Enter-net have become invaluable for facilitating rapid and appropriate management of international outbreaks.

Reported here is an outbreak of Salmonella enterica subsp. enterica serovar Madelia infection that occurred among 44 persons attending a silver anniversary reception in Hesse, Germany. Isolates of Salmonella Madelia are extremely unusual, and no outbreaks associated with this serotype have been reported previously. Forty-two attendees were interviewed and information was obtained from each of them regarding demographic and clinical characteristics and food consumed at the reception. Twenty-four attendees submitted stool samples for microbiological testing, and 10 of these were culture-positive for S. Madelia. Twenty-three attendees met the case definition of infection, while 18 met the clinical case definition (i.e. vomiting or diarrhoea within 3 days of consuming food at the reception) and five had asymptomatic infection with S. Madelia. The most likely vehicles of infection were tortellini and a red pesto sauce.

In the week following a carnival during 19-24 February 1998, an outbreak of meningococcal disease occurred in a rural German county. The available isolates belonged to phenotype C:2a:P1.2,5 and were clonally related by pulsed-field gel electrophoresis. A case-control study was done to identify risk factors for the outbreak and to define possible vaccination target groups. Five persons aged 13-16 years who fell ill during 24-27 February were included in the study. Four of 5 cases and 10 of 32 controls visited local discotheques (OR = 8.8; P = 0.06). Cases also visited discotheques more frequently than controls (chi2 for trend, P = 0.0002). Multiple discotheques during the carnival may have been predominant locations of transmission in this outbreak. Because this risk factor was limited in time, a mass community vaccination campaign was not initiated.