[The social dimension of tuberculosis in the City of Munich]. / Die soziale Dimension der Tuberkulose in der Stadt München.

Germany is a low-incidence country for tuberculosis, but there is no time for complacency. With an annual incidence of 10 per 100,000 population the City of Munich counts twice as many cases of tuberculosis compared to the national average. Reasons for the concentration of tuberculosis in big cities include the high proportion of migrants from countries with high prevalence of tuberculosis and from socioeconomically disadvantaged populations. Munich's population is growing fast and is expected to exceed 1.5 million in the near future. Migrants looking for employment now come predominantly from Romania, Bulgaria and Poland. The proportion of foreign born patients with tuberculosis increased over the last ten years from 49 to 80 %. Asylum seekers and migrants need special attention from the public tuberculosis services. The proportion of tuberculosis patients with social problems increased from 37 to 55 % over the last 6 years. Demands for medical and social support have increased and the case management is increasingly complex. In 2011 the ambulatory treatment of 6 immigrants was supervised by the public health services in Munich. Increasingly, uninsured patients from southeastern states of the European Union need medical treatment. In Europe the overall number of tuberculosis cases is decreasing. The proportion of multidrug-resistant (MDR) tuberculosis in Eastern Europe is alarming. 15 of worldwide 27 countries with the highest MDR load are located in the European Region. In Munich the number of MDR cases is still low at 1-4 cases each year. But duration, cost and side effects of therapy are strong barriers to treatment success. All patients have the right to get adequate diagnostic work-up and effective treatment no matter in which country they reside. To realize this request with cross-border control and care, is a big challenge to the public health service in a global perspective.

[First exchange of experiences concerning the H1N1 pandemic in Germany 2009/2010: report on a workshop held March 22-23, 2010, in Berlin]. / Erster Erfahrungsaustausch zur H1N1-Pandemie in Deutschland 2009/2010: Bericht über einen Workshop am 22. und 23. März 2010 in Berlin.

In April 2009 the first pandemic of the 21st century developed within a few weeks starting from Mexico. Its first wave reached Germany in autumn 2009 and was responsible for 1.8-3.5 million additional medical consultations. For the public health sector, this pandemic was one of the largest challenges of the last few decades. As a contribution to broader evaluations on national and international level, the Robert Koch Institute invited representatives from different professions involved in the pandemic response to participate in a workshop on 22-23 March 2010. This workshop was structured in short presentations, group work, and plenary discussions. Main experiences were that (a) pandemic preparedness was helpful, (b) the early warning systems were reliable, (c) vaccines were available within a few months, however, in limited amounts. Need for improvement was discussed for (a) effectiveness of vaccination logistics, (b) mechanisms for the reimbursement of the cost of vaccination, (c) availability of surveillance and monitoring systems, (d) integration of physicians in decision-making processes and health education, and (e) proactive communication strategies. Investments in the above mentioned areas can help to improve public health protection in the future.

[The City of Munich's preparations for an influenza pandemic]. / Vorbereitungen der Stadt München auf eine Influenzapandemie.

The publication of the German National Influenza Pandemic Plan initiated many public health activities at state and regional levels to get prepared for an influenza pandemic. Because of their population densities, urban areas will likely be affected earlier und more extensively. Therefore, the City of Munich started its preparations for a crisis situation early. The Division of Health and Environment of the City of Munich is the public health office responsible for putting plans into action. The main responsibilities are coordination and communication. Common measures to prevent and control infections on the basis of the Infectious Disease Control Act have to be implemented in a pandemic situation. The surveillance of influenza including laboratory diagnosis is highly sophisticated in Bavaria. Therapeutic means have developed significantly compared with the last pandemic in 1968. Nevertheless, at the peak of a pandemic, a shortage of personnel, hospital beds, vaccines and medications is expected. Priorities in the distribution of health resources should be defined in advance to help with decision making during the pandemic. Adequate communication with the public and all partners will be critical in order to reduce fear and unforeseen social disruption.

An outbreak of Salmonella München in Germany associated with raw pork meat.

In summer 2001, an outbreak of Salmonella München occurred in Germany. We conducted descriptive epidemiology and hypothesis-generating interviews among case patients, two retrospective cohort studies, and a case-control study of suboutbreaks. We performed pulsed-field gel electrophoresis (PFGE) from selected patient isolates and a limited trace-back investigation for analytical purposes. Four states were consecutively affected: Saxonia (SX), Brandenburg (BB), Berlin (BE), and Baden-Württemberg (BW). Although hypothesis-generating interviews failed to identify a plausible food item, descriptive data and investigations of the suboutbreaks suggested pork meat as a probable source in three states (SX, BB, and BE) but not in BW. The PFGE profiles from isolates of case patients in the first three states were indistinguishable but differed from PFGE profiles of case patients in BW. Trace-back investigation suggested that contamination of pork meat occurred early in the rearing-production chain. This outbreak demonstrates how contamination early in the production process that can yield different end products may complicate multistate outbreaks. Investigation of suboutbreaks and use of the trace-back method as investigational tools may be useful adjuncts in solving the problem of multistate outbreaks.

Prospective molecular epidemiological study on transmission of pulmonary Tuberculosis and Migration (MuT study) -- an interim report.

INTRODUCTION: In Western Europe prevalence and incidence of tuberculosis in the indigenous population is declining and TB in migrants from high prevalence countries is becoming a major issue of TB control. Resulting changes in transmission patterns need to be investigated to adapt control strategies. The MuT (Migration and Tuberculosis) study a co-operation among federal and local public health services (ODG), the National Surveillance Center (RKI) and the University has been established in Baden-Wuerttemberg to address these issues. OBJECTIVES: The goal of this ongoing study is to determine the transmission dynamics of TB in Baden-Wuerttemberg. Here, we present the first set of data on TB cases and their contacts and discuss strategies to overcome arising difficulties. METHODS: Prospective data collection of culture positive pulmonary tuberculosis cases and their contacts. Analysis of (1) routine data, (2) spatial data, (3) social interaction data, (4) molecular typing data, and (5) observational data of the implementation phase. RESULTS: The study demonstrates the capability of the study consortium to identify clusters. It provides valuable insights into current case detection and case management procedures and shows ways to improve. A set of factors has been identified that (a) facilitate and (b) discourage study participation. CONCLUSION: Collaboration among federal and local public health services (OGD), National Surveillance Center (RKI) and the University is a promising approach to investigate and improve TB control. This model has potentials for other infectious disease control.

Serological and epidemiological analysis of an outbreak of gastroenteritis among military recruits in Germany caused by Cryptosporidium parvum.

BACKGROUND: Cryptosporidium spp. cause enteritic disease worldwide. Besides those patients with an impaired immune system, the general population is also at risk. PATIENTS AND METHODS: Stool samples from participants of a military field exercise were tested for enteritic pathogens and sera were analyzed for Cryptosporidium-antibodies. All participants received a questionnaire for assessing possible risk factors. RESULTS: After a 5-day field training, 201 of a total of 450 soldiers (45%) developed acute gastroenteritis. Immediate microbiological analysis ruled out enteropathogenic bacteria and viruses as the cause of the disease. Only after hospitalization of one of the patients diagnostic procedures were expanded to the identification of parasites and Cryptosporidium parvum was identified. In addition, 14 fecal samples of 217 specimens were subsequently identified in a Cryptosporidium antigen ELISA. A serological analysis of 214 sera revealed 72% positive for specific IgG antibodies compared with 17% of a control group of soldiers who had not participated in the field training (relative risk 3.38; 95% CI 2.39-4.77; p < 0.001). Analysis of specific IgM levels was less conclusive. Epidemiological analysis of questionnaires correlated drinking of tap water, or consumption of various meals with gastroenteritis. However, the source of contamination could not be identified. CONCLUSION: Cryptosporidium spp. can cause acute enteritis even in healthy, young adults as demonstrated by this outbreak. Using serological methods, the extent of the outbreak could be estimated in a retrospective analysis.

Subclass-specific serological reactivity and IgG4-specific antigen recognition in human echinococcosis.

Immunoglobulin (Ig) subclass-specific antibody responses and isotype-specific recognition of E. multilocularis (Em) and E. granulosus (Eg) antigens (Ag) were evaluated in both alveolar echinococcosis (AE) and cystic echinococcosis (CE). AE patients were divided into 3 groups by clinical and therapeutic criteria according to their actual state of infection, i.e. elimination of parasite, and regression or progression of disease, CE patients were either before or after surgery, of in continuous chemotherapy due to parasite persistence. Total IgE was highly elevated in progressive AE cases (7/11), but not in the cases with eliminated infection or regression. In AE patients with active disease, EmAg-specific IgE, total IgG, IgG1, IgG2 and IgG4 were particularly high. Similarly, in 9 of 30 CE patients, total IgE was raised above reference values, indicating progressive disease. CE patients" sera antibody cross-reacted with crude EmAg, and detectable Ig levels of the same isotype were also measured by ELISA. In both AE and CE, parasite-specific antigen recognition was dominated by IgG1 and IgG4. In AE patients with progressive disease, IgG4 distinctively recognized low molecular weight EmAg of Ar 26 kD, 18 kD, 16 kD and 12 kD. As prominent IgG4 and IgE responses develop with chronic helminth infections only, these serological parameters may indicate successful parasite infestation and severe outcome of disease. In summary, analyses of immunoglobulin isotype responses in AE patients by ELISA in combination with immunoblotting are a useful approach for post-treatment follow-up of patients at risk of developing recrudescent disease.

Pericystic metabolic activity in alveolar echinococcosis: assessment and follow-up by positron emission tomography.

Information on parasite viability in alveolar echinococcosis (AE) cannot be obtained by conventional imaging techniques. We evaluated the glucose metabolism of AE lesions by use of [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) in 12 inoperable patients. Eight patients showed either perilesional or focal enhancement ("hot spots"), whereas 4 patients had nonenhancing (metabolically inactive) lesions. With PET, necrotic parasitic lesions and areas of enhanced metabolic activity could be clearly discriminated. Most notably, 3 of 8 patients with metabolically active lesions who were reexamined after chemotherapy treatment clearly showed improvement: the initial surrounding hot spots had disappeared in 2 of them, and had significantly decreased in 1. PET may prove valuable in assessing the efficacy of chemotherapy by showing the disappearance of metabolic activity and may also be useful for timely detection of relapses and metastases. Although costly and not readily available, FDG-PET is a promising tool toward improved management of AE and may thus help lower costs of long-term chemotherapy.

Cytokine and chemokine secretion by human peripheral blood cells in response to viable Echinococcus multilocularis metacestode vesicles.

In human alveolar echinococcosis, asexually proliferating metacestodes of Echinococcus multilocularis progressively infiltrate host tissues and cause serious pathology to the affected organs. This study employed an in vitro culture of E. multilocularis and examined the production of cytokines and chemokines by peripheral blood cells from echinococcosis patients in response to viable proliferating E. multilocularis metacestode vesicles (Em-vesicles). A significant interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) production was elicited in echinococcosis patients when their cells were cocultured with viable Em-vesicles and autologous immune sera. Furthermore, in echinococcosis patients, substantial amounts of cytokines were detected; and the levels of IL-12 and IL-13 found in patients correlated with the actual state of clinical disease. These observations suggest that viable E. multilocularis vesicles will induce significant cellular production of cytokines and chemokines in patients, and that such immune mediators may activate and enhance antibody-dependent cellular effector mechanism against proliferating metacestodes of E. multilocularis.

Experimental onchocerciasis in chimpanzees. Cell-mediated immune responses, and production and effects of IL-1 and IL-2 with Onchocerca volvulus infection.

Nine of eighteen chimpanzees inoculated with infective third-stage larvae of Onchocerca volvulus developed patent infection with microfilariae in skin biopsies. In all infected chimpanzees the in vitro cellular reactivity to O. volvulus adult worm-derived Ag (OvAg) increased significantly after exposure to third-stage larvae. However, during prepatency the in vitro cellular responses to OvAg decreased gradually in subsequently mf positive (patent) animals, and returned with patency to values not different to those before infection. In non-patent chimpanzees cellular responses remained significantly higher than before infection. Stimulation of PBMC in vitro with bacterial Ag and mitogen did not show any differences between the experimental groups through 20 months p.i. The addition of exogenous IL-2 did not restore the impaired responses of PBMC to OvAg in patent animals. Exogenous IL-2 elicited an additive increase of the cellular response to OvAg in nonpatent, and a mitogenic effect to OvAg in patent animals. Selective depletion of adherent, suppressor/cytotoxic (CD8+), NK cells (CD16+) and the use of autologous serum had no effect on antigenic and mitogenic cellular responsiveness. OvAg-induced IL-2 production decreased after patency, whereas, IL-1 production was significantly greater in both patent and nonpatent than in control chimpanzees. In summary, these data demonstrate that experimental O. volvulus infection in chimpanzees stimulated a substantial cell-mediated immune response. In patent chimpanzees an OvAg-specific cellular hyporesponsiveness occurred before onset of patency, possibly due to decreased IL-2 production and responsiveness.

Ivermectin-facilitated immunity in onchocerciasis. Reversal of lymphocytopenia, cellular anergy and deficient cytokine production after single treatment.

A longitudinal investigation has been conducted into the cell-mediated immune responses of onchocerciasis patients after a single-dose treatment with ivermectin. Untreated patients tested for delayed cutaneous hypersensitivity (DCH) to seven recall antigens showed lower responses than infection-free control individuals (P less than 0.01), but 6 and 14 months after treatment DCH reactions increased to similar levels to those seen in the controls. The in vitro cellular reactivity to Onchocerca volvulus-derived antigen (OvAg) was reduced in untreated patients as compared with controls, and the lymphocyte blastogenic responses to OvAg and streptolysin-O clearly improved up to 14 months after treatment. Peripheral blood mononuclear cells (PBMC) from untreated patients produced IL-1 beta, tumour necrosis factor-alpha (TNF-alpha) and IL-6 in response to mitogenic stimulation with phytohaemagglutinin (PHA), only low levels of IL-1 beta, IL-2 and TNF-alpha in response to OvAg, but higher amounts of IL-4 and interferon-gamma (IFN-gamma) in response to OvAg than control individuals. After ivermectin treatment, the OvAg-induced production of IL-1 beta and TNF-alpha increased significantly 1 and 14 months after treatment. The PHA-induced production of IL-2 and IL-4 increased 1 month after treatment and remained significantly elevated until 14 months after treatment, whereas the OvAg-specific secretion of IL-2, IL-4 and IFN-gamma did not change after ivermectin treatment. Flow cytometric analysis of lymphocyte-subsets in the peripheral blood of untreated patients revealed a relative and absolute (P less than 0.01) diminution of CD4+ cells and a significantly smaller CD4+/CD8+ cell ratio as compared with controls. By 4 weeks after treatment and thereafter, CD4+ T cells increased relatively and absolutely (P less than 0.01); likewise there was an absolute increase in T-helper-inducer cells (CD4+CD45RO+) and a temporarily improved CD4+/CD8+ cell ratio (P = 0.001). The expression of the low-affinity receptor for IgE (CD23) on total lymphocytes decreased from 14% to 7% by 14 months after treatment. The CD8+ cells and CD3+TCR gamma delta + cells were higher in patients than in controls and both remained elevated until 14 months after treatment. These results suggest a distinctly improved cellular immunity in human onchocerciasis that was facilitated by ivermectin therapy.

Experimental onchocerciasis in chimpanzees. Antibody response and antigen recognition after primary infection with Onchocerca volvulus.

Nine of 18 chimpanzees inoculated with 250 infective third-stage larvae (L3) each developed patent (i.e., positive for microfilariae) Onchocerca volvulus infection. Four of 6 infected chimpanzees that received 200 micrograms/kg ivermectin at 28 days postinfection (pi) became patent, whereas, when ivermectin was given concurrently with L3 challenge only 1 of 6 infected animals developed patent infection. The antibody response to O. volvulus adult worm-derived antigens (OvAg) showed clear differences between patent and nonpatent chimpanzees. Three months pi, all sera detected several OvAg in the range of M(r) 35-120 k. Sera collected 6 mo pi from later patent animals recognized increasing numbers of OvAg, especially in the lower MW range of M(r) 13 to 33 k. Beginning 10 months pi Onchocerca-antigens of M(r) 21, 24, 26, and 28 k were detected only by patent chimpanzee's sera. The antibody response in nonpatent chimpanzees consistently recognized fewer OvAg, most of which were limited to the higher M(r) range (35-120 k). The reactivity of sera from infected chimpanzees to a low molecular weight fraction (LMW) of total OvAg doubled within 6 months pi, and increased continuously in patent animals from 13 until 30 months pi. Serological reactivity of nonpatent animals to LMW-OvAg remained low. The titers of circulating IgG directed against total OvAg increased in all infected chimpanzees, and continued to rise with patency. In nonpatent chimpanzees the antibody production gradually returned to preinfection values. Total and OvAg-specific IgE increased in patent and nonpatent chimpanzees. Also, during prepatency the granulocyte and antibody-mediated in vitro killing of microfilariae of O. volvulus increased in subsequently patent chimpanzees. The in vitro immobilization of L3 remained low.

Ivermectin-facilitated immunity in onchocerciasis; activation of parasite-specific Th1-type responses with subclinical Onchocerca volvulus infection.

The present study examined the quantitative and qualitative changes registered in the parasite-specific antibody response, cellular reactivity and cytokine production profile in onchocerciasis patients repeatedly treated with ivermectin over a period of 8 years. The densities of Onchocerca volvulus microfilariae (mf) in treated patients remained significantly reduced, whereas the number of permanently amicrofilaridermic patients (subclinical infection) increased with repeated treatments. In vitro cellular responses to O. volvulus antigen (OvAg) were highest (P < 0.01) in untreated control individuals exposed to infection, but negative for mf of O. volvulus (endemic normals). Cellular reactivity in repeatedly treated patients was higher at 84 than at 36 months post initial treatment (p.i.t); furthermore, the proliferative responses to OvAg, mycobacterial purified protein derivative (PPD) and streptococcal SL-O were greater (P < 0.05) at 84 months p.i.t. in amicrofilaridermic than in microfilaria-positive onchocerciasis patients. In amicrofilaridermic patients such reactivity approached the magnitude observed in endemic normals. Peripheral blood mononuclear cells (PBMC) from patients and endemic normals produced equivalent amounts of IL-2, IL-4 and interferon-gamma (IFN-gamma) in response to mitogenic stimulation with phytohaemagglutinin (PHA); in response to OvAg, however, significantly more IL-2 and IFN-gamma were produced by PBMC from subclinical amicrofilaridermic patients or endemic normals than by mf-positive patients. OvAg-specific production of IL-4 by PBMC from treated patients was lower at 84 than at 36 months p.i.t. At three months p.i.t. the titres of circulating OvAg-specific IgG1-3 had increased (P < 0.05), but they then continuously declined with repeated treatments. Only IgG1 and IgG4 bound to OvAg of mol. wt 2-12 kD at 1 month p.i.t., while recognition of OvAg of mol. wt 10-200 kD by IgG1, IgG2 and IgG4 reached a maximum intensity at 3-6 months p.i.t., with the overall intensity of binding to OvAg gradually weakening thereafter. These results suggest that onchocerciasis-associated immunosuppression is reversible following ivermectin-induced permanent clearance of microfilariae from the skin; and that a vigorous parasite-specific cellular reactivity and a sustained production of IL-2 and IFN-gamma in amicrofilaridermic individuals may contribute to controlling O. volvulus infection.

The diverse expression of immunity in humans at distinct states of Onchocerca volvulus infection.

This study examined the development and persistence of immunity in humans presenting defined states of Onchocerca volvulus infection, i.e. in exposed endemic control individuals without microfilaridermia and clinical disease, in patients with patent or post-patent onchocerciasis, and in patients concurrently infected with Mansonella perstans. Onchocerca volvulus antigen (OvAg)-specific cellular reactivity was significantly diminished in microfilariae (mf)-positive patients, while the highest reactivity was measured in exposed but mf-negative endemic controls, those being free of any clinical signs of onchocercal disease. In patients who became post-patent, responses to OvAg were significantly augmented, but did not approach entirely the magnitude observed in endemic controls. In onchocerciasis patients with concurrent mansonelliasis, cellular unresponsiveness to OvAg persisted, even when mf of O. volvulus were eliminated permanently by repeated ivermectin therapy. Cells from mf-positive onchocerciasis patients produced significantly less interferon-gamma (IFN-gamma) (P < 0.01) and interleukin-5 (IL-5) (P < 0.05) in response to OvAg than those taken from endemic controls or post-patent individuals in whom IFN-gamma and IL-5 production was similarly high. In contrast, both OvAg-driven as well as spontaneous IL-10 secretion was higher in mf-positive patients than in endemic controls or post-patent cases. In all individuals examined, serological recognition of OvAg by immunoglobulins was dominated by IgG4; in mf-positive patients OvAg of 205,000-12,000 molecular weight (MW) were strongly bound. In post-patent individuals, and similarly in endemic controls. OvAg recognition by IgG4 varied from intense (with numerous antigens being recognized) to weak or absent antigen binding. Significantly elevated OvAg-specific IgG isotypes were measured in mf-positive onchocerciasis patients in comparison with endemic controls or post-patent individuals (with the exception of IgG3). IgG1, IgG2 and IgE were higher, but IgG4 was lower in endemic controls compared with post-patent onchocerciasis patients. The ratios of IgG4/IgG1 differed (P < 0.001) between endemic controls and mf-positive or post-patent onchocerciasis patients, with IgG4/IgG1 ratios of R < 3.0 being characteristic for endemic controls and post-patent O. volvulus infection. In conclusion, this cross-sectional immunoepidemiological investigation showed that distinct states of O. volvulus infection correlate with a particular cellular and humoral immune response. The mf-free condition appeared to be associated with a vigorous parasite-specific cellular reactivity and a particular cytokine production profile, while concurrent M. perstans infection depressed OvAg-specific cellular responsiveness. Antibody responses, in all likelihood, reflected the intensity and state of infection, and not the degree of acquired immunity protective against parasite aggregation.