A cluster of two human cases of tick-borne encephalitis (TBE) transmitted by unpasteurised goat milk and cheese in Germany, May 2016.

In May 2016, two cases of tick-borne encephalitis (TBE) were confirmed by serology (positive IgM and IgG antibodies against TBE virus (TBEV) in serum), with a possible link to raw milk and cheese from a goat farm in a region in Baden-Württemberg, Germany not previously known as TBE-endemic. The outbreak investigation identified 32 consumers of goat dairy products (29 consumers, one farm employee, two owners) of whom none had IgM antibodies against TBEV 3-8 weeks after consumption. Of the 27 notified TBE cases in the State, none reported consumption of raw goat milk or cheese from the suspected farm. Five of 22 cheese samples from 18 different batches were RT-qPCR-positive for TBEV -genome, and two of the five samples were confirmed by virus isolation, indicating viability of TBEV in the cheese. Nine of the 45 goats had neutralising TBEV antibodies, two of them with a high titre indicating recent infection. One of 412 Ixodes ricinus was RT-qPCR-positive, and sequencing of the E gene from nucleic acid extracted from the tick confirmed TBEV. Phylogenetic analyses of tick and cheese isolates showed 100% amino acid homology in the E gene and a close relation to TBEV strains from Switzerland and Austria.

Prevalence of type I sensitization to alpha-gal in forest service employees and hunters.

BACKGROUND: The production of IgE molecules specific to the carbohydrate galactose-α-1,3-galactose (alpha-gal) is known to induce delayed anaphylaxis against mammalian meat. Tick bites constitute the primary sensitization source, as ticks transfer alpha-gal in their saliva to a host during a bite. The reported prevalence of alpha-gal-specific IgE (alpha-gal-sIgE) positivity varies between different populations from diverse geographic regions. OBJECTIVE: To investigate the prevalence of alpha-gal-sIgE positivity in a population of forest service employees who are highly exposed to ticks in comparison with a residential population and a historic sample. METHODS: A cross-sectional study evaluating 300 forest service employees and hunters from southwest Germany was performed. Alpha-gal-sIgE levels were assessed by ImmunoCAP assay. The prevalence of alpha-gal-sIgE-positive individuals was compared with a matched cohort composed of a residential population and blood samples from forest service employees collected 15 years ago. RESULTS: In the study population, the prevalence of alpha-gal-sIgE-positive (≥0.10 kUA /L) individuals was 35.0%, whereas the prevalence of individuals with alpha-gal-sIgE levels ≥0.35 kUA /L was 19.3%. Alpha-gal-sIgE positivity was associated with total IgE levels and recent tick bites. Mammalian meat-induced delayed anaphylaxis was found in 8.6% of the participants with alpha-gal-sIgE levels ≥0.35 kUA /L. For forest service employees and hunters, the odds ratio for alpha-gal-sIgE positivity was 2.48 compared to the residential population. The prevalence of alpha-gal-sIgE positivity in the current and historic cohort was comparable. CONCLUSION: Forest service employees and hunters compose a population with a high prevalence of alpha-gal-sIgE positivity and carry a considerable risk of red meat allergy.

[Chronic skin ulcer in a 24-year-old man after a journey to Southeast Asia]. / Chronisches Ulkus nach Südostasienreise bei 24­jährigem Mann.

Our report concerns a 24-year-old man with a chronic exsudative skin lesion after a journey to Southeast Asia. The diagnosis of melioidosis was made by the identification of Burkholderia pseudomallei from the ichor. The diagnosis was confirmed by polymerase change reaction. The patient was treated with meropenem i. v. for about 10 days and with trimethoprim/sulfamethoxazole for the following 12 weeks. Melioidosis is an endemic disease in Southeast Asia and North Australia which in some cases can run a severe course and can have a high fatality rate. The relevance of melioidosis becomes more important against the background of the increasing global movement of travelers and migration.

[The ecology of ticks, tick-borne diseases and biological tick control in Baden-Württemberg]. / Ökologie von Zecken als Überträger von Krankheitserregern in Baden-Württemberg und biologische Zeckenbekämpfung.

Ticks and tick-borne diseases are of great significance for the health of humans and animals. However, the factors influencing their distribution and dynamics are inadequately known. In a project financed by the Baden-Württemberg Ministry of the Environment, Climate and Energy Industry, as part of the program BWPLUS, interdisciplinary specialists work together to determine the influence of weather, (micro)climate, habitat, land use, human activities, and the population dynamics of host animals on the distribution and abundance of ticks and the diseases that they transmit in Baden-Württemberg. The project comprises four modules: the large-scale distribution of ticks in Baden-Württemberg (module 1), detailed studies of host-tick-pathogen interaction in relation to the microclimate (module 2), and the spatial occurrence of important tick-borne pathogens (module 3). The fourth module involves the comprehensive analysis and synthesis of all data in order to determine the relative importance of the factors studied and to develop a risk model. Recently, intensive investigations into tick control have been undertaken using various entomopathogenic fungi and nematodes as well as a parasitoid wasp. Our aim was to determine whether these natural enemies could be used to effectively reduce the number of free-living ticks.

Network "Rodent-borne pathogens" in Germany: longitudinal studies on the geographical distribution and prevalence of hantavirus infections.

Hantavirus infections are known in Germany since the 1980s. While the overall antibody prevalence against hantaviruses in the general human population was estimated to be about 1-2%, an average of 100-200 clinical cases are recorded annually. In the years 2005 and 2007 in particular, a large increase of the number of human hantavirus infections in Germany was observed. The most affected regions were located in the federal states of Baden-Wuerttemberg, Bavaria, North Rhine Westphalia, and Lower Saxony. In contrast to the well-documented situation in humans, the knowledge of the geographical distribution and frequency of hantavirus infections in their rodent reservoirs as well as any changes thereof was very limited. Hence, the network "Rodent-borne pathogens" was established in Germany allowing synergistic investigations of the rodent population dynamics, the prevalence and evolution of hantaviruses and other rodent-associated pathogens as well as their underlying mechanisms in order to understand their impact on the frequency of human infections. A monitoring of hantaviruses in rodents from endemic regions (Baden-Wuerttemberg, Bavaria, North Rhine Westphalia, Lower Saxony) and regions with a low number of human cases (Mecklenburg Western-Pomerania, Brandenburg, Saxony, Saxony-Anhalt) was initiated. Within outbreak regions, a high prevalence of Puumala virus (PUUV) was detected in bank voles. Initial longitudinal studies in North Rhine Westphalia (city of Cologne), Bavaria (Lower Bavaria), and Lower Saxony (rural region close to Osnabrück) demonstrated a continuing presence of PUUV in the bank vole populations. These longitudinal studies will allow conclusions about the evolution of hantaviruses and other rodent-borne pathogens and changes in their distribution, which can be used for a risk assessment of human infections. This may become very important in order to evaluate changes in the epidemiology of rodent-borne pathogens in the light of expected global climate changes in the future.

First evidence of Babesia gibsoni (Asian genotype) in dogs in Western Europe.

Canine babesiosis in Europe is generally caused by Babesia canis canis and Babesia canis rossi. Here we describe the first two autochthonous cases of Babesia gibsoni (Asian genotype) infection in Germany. Two American pit bull terriers showed clinical and hematologic signs consistent with babesiosis. Polymerase chain reaction (PCR) analysis of the 18S rDNA of blood samples revealed 486 bp fragments. The sequences were 100% identical to each other and 100% identical to Babesia gibsoni (Asian genotype). These results represent the first genetic evidence of Babesia gibsoni (Asian genotype) parasites in dogs in Western Europe.

[Importance of PCR for the diagnostics of canine babesiosis]. / Bedeutung der PCR in der Diagnostik der caninen Babesiose.

Clinical standards to confirm babesiosis in dogs include the direct identification of the infectious agent in blood smears and serological assays for Babesia canis-specific antibodies. Here, we demonstrate in seven cases (with data on anamnesis, clinics, laboratory diagnostics, and therapeutic outcomes) that a new diagnostic procedure is required. This is the molecular-genetic identification of babesia by real time PCR allowing an unequivocal identification of the infectious agents. Indeed, all seven patients presenting severe clinical symptoms were PCR-positive, but only two of them had specific antibodies and showed babesia in their bloodstream. Six of the dogs appeared to have acquired babesiosis while travelling abroad, and one in the Swiss canton of Schaffhausen.

[The occurrence of Coxiella burnetii in sheep and ticks of the genus Dermacentor in Baden-Wuerttemberg]. / Untersuchungen zum Vorkommen von Coxiella burnetii bei Schafen und Zecken der Gattung Dermacentor in Baden-Württemberg.

This study examined the occurrence of Coxiella burnetii (C. burnetii), the infectious agent of Q-fever, in sheep and sheep-ticks in Baden-Wuerttemberg, Germany, as a possible source of infection in Q-fever outbreaks. Using PCR, we examined a total of 1066 Dermacentor ticks from 23 herds and 49 samples of tick excrement from 18 herds for C. burnetii. We found the infectious agent in one non-engorged tick and in one sample of tick excrement from the same herd, in Efringen-Kirchen (district Loerrach). Sequencing the PCR-products confirmed the amplifications as specific for C. burnetii. Further serological tests of random samples of the four districts of Baden-Wuerttemberg showed a seroprevalence from 0 to 1.4% using complement fixation test (CFT), as well as a 0.9 to 10.2% seroprevalence, using ELISA test. Serum samples from a Q-fever-suspicious herd resulted, however, in 6% (CFT) and 53% (ELISA) positive reactions. A comparison between CFT and ELISA showed both a correlation of the two test methods that increased with higher CFT titration levels and positive reactions using ELISA for 9.4% of the serums that had tested negative using CFT. The results of the present study reveal that ticks and their excrements are important vectors of transmission of Q-fever in Baden-Wuerttemberg. Investigations on C. burnetii using PCR as well as serological surveys of sheep are important instruments for diagnosis and disease control of Q-fever.

Neotrombicula autumnalis (Acari, Trombiculidae) as a vector for Borrelia burgdorferi sensu lato?

Larvae of the trombiculid mite Neotrombicula autumnalis were collected at 18 sites in and around Bonn, Germany, to be screened for infection with Borrelia burgdorferi s.l. by means of PCR. Questing larvae numbering 1380 were derived from the vegetation and 634 feeding ones were removed from 100 trapped micromammals including voles, mice, shrews and hedgehogs. In a laboratory infection experiment, a further 305 host-seeking larvae from the field were transferred onto Borrelia-positive mice and gerbils, and examined for spirochete infection at various intervals after repletion. In three cases borrelial DNA could be amplified from the mites: (1) from a larva feeding on a wild-caught greater white-toothed shrew (Crocidura russula), (2) from a pool of four larvae feeding on a B. garinii-positive laboratory mouse, and (3) from a nymph that had fed on a B. afzelii-positive laboratory gerbil as a larva. In the first case, borrelial species determination by DNA hybridization of the PCR product was only possible with a B. burgdorferi complex-specific probe but not with a species-specific one. In the second case, probing showed the same borrelial genospecies (B. garinii) as the laboratory host had been infected with. In the latter case, however, DNA hybridization demonstrated B. valaisiana while the laboratory host had been infected with B. afzelii. Subsequent DNA sequencing confirmed much higher similarity of the PCR product to B. valaisiana than to B. afzelii indicating an infection of the mite prior to feeding on the laboratory host. The negligible percentage of positive mites found in this study suggests that either the uptake of borrelial cells by feeding trombiculids is an extremely rare event or that ingested spirochetes are rapidly digested. On the other hand, the results imply a possible transstadial and transovarial transmission of borreliae once they are established in their trombiculid host. However, unless the transmission of borreliae to a given host is demonstrated, a final statement on the vector competence of trombiculid mites is not possible.

[Tick-borne encephalitis and Lyme borreliosis. Spread of pathogens and risk of illness in a tick-borne encephalitis region]. / FSME und Lyme-Borreliose. Erregerverbreitung in Zecken und Erkrankungsrisiken in einem FSME-Risikogebiet.

A knowledge of the distribution of tick-borne agents and the related risks of contracting diseases are essential to ensure an appropriate response between hysteria and disregard, and to decide the appropriateness of vaccination. Illustrated by the German town of Lohr a. M. (Bavaria), the prevalence of TBE-virus and Borrelia burgdorferi in ticks was investigated and compared, and the respective risk of contracting disease from a bite assessed. Using the polymerase chain reaction (PCR), a total of 1657 ticks obtained from five different biotopes around Lohr were examined for the TBE-virus, and 408 ticks for Borrelia burgdorferi. The results were compared with earlier findings in other regions of Germany. The risk of contracting illness was estimated on the basis of transmission and manifestation rates, together with epidemiological data from the region. The prevalence of TBE-virus was 0.12% (95% CI: 0.05-0.44%) in the ticks investigated. This is comparable with that in 4 other regions rated as TBE-risk regions, but significantly lower than that in rated high-risk regions. Borrelia burgdorferi was detected in 14.9% (11.8-19.0%) of adult ticks, roughly twice the prevalence found in nymphs (7.2%, range 4.6-11.7%). On the basis of these prevalences, the risk of contracting meningitis/encephalitis from a tick bite is about 1:10,000, and the risk for Lyme Borreliosis is about 1:100, the latter requiring that the tick remains attached for at least 2-3 days.

[Epidemiology of hantaviruses in Baden-Wurttemberg]. / Epidemiologie von Hantaviren in Baden-Württemberg.

Hantavirus, originally named after the Hantaan River in Korea, is the aetiologic agent for the Hemorrhagic Fever with Renal Syndrome (HFRS) in the asian region, in the Americas for the Hantavirus Pulmonary Syndrome (HPS). In Middle Europe hantaviruses are responsible for the "Nephropathia Epidemica" (NE), a mild form of HFRS. Hantaviruses belong to the family of Bunyaviridae. Like other members of this family their genome consists of three segments of single stranded RNA (ss-RNA) leading to various subtypes, strongly associated with different rodent hosts. There are two major groups, the hantaan lineage harbored by murine rodents and the Puumala lineage harbored by arvicolidae ("old world") and sigmodontidae ("new world"). Infected rodents may develop chronic infections for months or even life-long and may shed infectious virus with urine and feces. The primary mode of infection of man occurs by inhaling contaminated aerosols or soil particles. The collection of epidemiologic data in the state of Baden-Württemberg was realized in three different steps: Collection and localisation of clinical cases (n = 62): A concentration of clinical cases in the middle of the state was found. The examination of the seroprevalence of exposed persons: By the examination of 4000 sera from forest workers, a seroprevalence with an average of 2.1% was found. In the districts of Reutlingen and Tübingen seroprevalences up to 9% were found. This leads to the assumption that there are endemic areas. Epidemiologic studies of reservoir hosts: Serologic surveys of rodents (n = 1150) in the described areas yielded to a seroprevalence up to 10-30%. Virus carriers were determined with RT-PCR and nested-PCR testing. The prevalence in the rodent population showed an average of 10%. The isolated subtypes were all identified as members of the Puumala-lineage. The origin of sporadic infections with Hantavirus of the Hantaan-lineage in Baden-Wuerttemberg is still unknown.

Detection and molecular typing of Borrelia burgdorferi sensu lato in Ixodes ricinus ticks and in different patient samples from southwest Germany.

The prevalence of different genospecies of Borrelia burgdorferi sensu lato in infected ticks could be a determinant for the risk of acquiring Lyme borreliosis (LB) and its clinical presentation. A total of 7373 ticks and 2761 samples from LB patients from the same area in southwest Germany were analyzed by PCR to assess the frequency of the occurrence of LB-associated genospecies. Fifteen percent of the tick samples and 19% of the human samples were found positive for the presence of B. burgdorferi sensu lato. Further identification of 1106 B. burgdorferi sensu lato positive tick samples by reverse line blotting and 125 positive patient samples by nested PCR using species-specific primers revealed the occurrence of B. afzelii, B. burgdorferi sensu stricto, B. garinii and B. valaisiana. Both single-species and mixed infections were noted and a similar distribution of the different genospecies was found in ticks compared with human samples. It was also the purpose of this study to obtain more information about a possible correlation between the distribution of Borrelia species and clinical syndromes of LB. Skin biopsies of 59 patients with acrodermatitis chronica atrophicans and cerebrospinal fluid samples from 78 patients with possible neuroborreliosis were analyzed. In conclusion, the distribution of the different genospecies in ticks is the decisive factor for the occurrence of the different Borrelia genospecies in samples from LB patients. Borrelia afzelii is the predominant genospecies in all kind of samples from the observed area and there seems to be no association of particular Borrelia genospecies with distinct clinical manifestations of LB.

Transmission risk of Borrelia burgdorferi sensu lato from Ixodes ricinus ticks to humans in southwest Germany.

The risk of Borrelia burgdorferi infection and the value of antibiotic prophylaxis after tick bite are controversial. In this study, performed in two areas of southwestern Germany, ticks were collected from 730 patients and examined by the polymerase chain reaction (PCR) for B. burgdorferi. To assess whether transmission of B. burgdorferi occurred, the patients were clinically and serologically examined after tick removal and during follow-up examinations. Data from all tick bites gave a total transmission rate of 2.6% (19 patients). Eighty-four ticks (11.3%) were PCR positive. Transmission occurred to 16 (26.7%) of 60 patients who were initially seronegative and could be followed up after the bite of an infected tick. These results indicate that the transmission rate from infected ticks in Europe is higher than previously assumed. Examination of ticks and antibiotic prophylaxis in the case of positivity appears to be indicated.

Mutation analysis of beta-thalassemia genes in a German family reveals a rare transversion in the first intron.

Thalassemia major is a rare disorder in the German population. We describe here the characterization of the beta-globin genes of a German patient homozygous for beta-thalassemia. Gene cloning and sequencing revealed a G to T transversion at the intron 1 donor site of the beta-globin gene on both chromosomes.

Haemoglobin Freiburg: direct detection by synthetic oligonucleotide probes.

The molecular defect leading to Haemoglobin (Hb) Freiburg has been analysed using synthetic oligonucleotides. Oligonucleotide probes 19 residues and 16 residues long, corresponding to the normal and mutant beta-globin gene sequences, respectively, were used to develop a direct assay for the beta F-globin gene, which codes for an unstable haemoglobin. Under the conditions described here the use of the respective synthetic oligonucleotides should aid in the determination of all Hb Freiburg genotypes in families at risk with a high level of confidence.

[Experiences with prenatal diagnosis of sickle cell anemia and thalassemias in the first trimester of pregnancy: various aspects for the obstetrician]. / Erfahrungen mit der pränatalen Diagnostik von Sichelzellenanämie und Thalassämien im ersten Schwangerschaftstrimenon: Aspekte für den Frauenarzt.

After an extensive educational campaign for the medical community in the area of the Westf. Wilhelms-University Münster five pregnancies at risk for sickle cell anemia and thalassemias were investigated during the first trimester of pregnancy. Following chorionic villi sampling in one case a sickle cell anemia and in two other cases a beta-thalassemia could be excluded. In two additional cases a homozygous beta-thalassemia was proven and in one of the cases the first trimester diagnosis was confirmed in the second trimester by fetal blood sampling. Because of the migration patterns in Europe there is currently a considerable demand for prenatal diagnosis of beta-thalassemias in West-Germany after proper information of the population at risk.