Ticks and tick-borne diseases from Mallorca Island, Spain.

Ixodid ticks are obligate blood-feeding arthropods and important vectors of pathogens. In Mallorca, almost no data on the tick fauna are available. Herein, we investigated ticks and tick-borne pathogens in ticks collected from dogs, a cat and humans in Mallorca as result of a citizen science project. A total of 91 ticks were received from German tourists and residents in Mallorca. Ticks were collected from March to October 2023 from dogs, cat and humans, morphologically and genetically identified and tested for pathogens by PCRs. Six tick species could be identified: Ixodes ricinus (n = 2), Ixodes ventalloi (n = 1), Hyalomma lusitanicum (n = 7), Hyalomma marginatum (n = 1), Rhipicephalus sanguineus s.l. (n = 71) and Rhipicephalus pusillus (n = 9). Rhipicephalus sanguineus s.l. adults were collected from dogs and four females from a cat and the 16S rDNA sequences identified it as Rh. sanguineus s.s. Hyalomma lusitanicum was collected from 1 human, 1 dog and 5 specimens were collected from the ground in the community of Santanyi, together with one H. marginatum male. This is the first report of Hyalomma marginatum in Mallorca. Both I. ricinus were collected from humans and I. ventalloi female was collected from a dog. All ticks tested negative for Anaplasma phagocytophilum, Coxiella spp., Francisella spp., and piroplasms. In 32/71 (45%) specimens of Rh. sanguineus s.s., Rickettsia spp. could be detected and in 18/32 (56.2%) sequenced tick DNAs R. massiliae was identified. Ixodes ventalloi female and both I. ricinus tested positive in the screening PCR, but the sequencing for the identification of the Rickettsia sp. failed.

Exotic ticks removed from German travelers.

We report the finding of five nymphs and three adult ticks attached to German tourists while traveling the American continents. All eight specimens were morphologically identified and confirmed genetically using the 16S rRNA gene and screened for Rickettsia spp. infections. Five tick species were identified: one Amblyomma mixtum nymph from Ecuador, one Amblyomma varium nymph from Colombia, three Amblyomma coelebs nymphs from Costa Rica, one Amblyomma americanum male from the USA, one Dermacentor andersoni female and one D. andersoni male from Canada. Tick-borne microorganisms screening using the pan-Rickettsia-PCR resulted in two positive and six negative ticks. The A. mixtum nymph was positive for Rickettsia amblyommatis, while the D. andersoni female was positive for Rickettsia peacockii.

Tick-borne encephalitis virus IgG antibody surveillance: vaccination- and infection-induced seroprevalences, south-western Germany, 2021.

BackgroundThe exact epidemiology of tick-borne encephalitis virus (TBEV) infections is unknown because many TBEV infections have an influenza-like or asymptomatic course. Surveillance data are based on patients with any (predominantly neurological) symptoms that prompted diagnostic testing. Infection- and vaccine-induced antibodies against TBEV can be distinguished using an NS1 IgG ELISA.AimIn a seroprevalence study we aimed to investigate TBEV antibody prevalence, incidences, manifestation indices and potential protection rates in a highly endemic district in south-western Germany.MethodsWe analysed 2,220 samples from healthy blood donors collected between May and September 2021. The reported number of TBEV infections was provided on a sub-district level by the local public health authorities. Blood samples were first screened using a TBEV IgG ELISA. In a second step, all positive samples were further analysed with a recently established NS1 IgG ELISA. The presence of specific antibodies against TBEV (excluding cross-reacting antibodies against other flaviviruses) was confirmed by testing screening-positive samples with a microneutralisation assay.ResultsOf 2,220 included samples, 1,257 (57%) tested positive by TBEV IgG ELISA and 125 tested positive for infection-induced TBEV NS1 antibodies, resulting in a TBEV NS1 IgG seroprevalence at 5.6% in our population. The yearly incidence based on the NS1 ELISA findings resulted in 283 cases per 100,000 inhabitants.ConclusionUsing the TBEV NS1 IgG assay, we confirmed a manifestation index of ca 2% and a high incidence of predominantly silent TBEV infections (> 250/100,000/year), which exceeds the incidence of notified cases (4.7/100,000/year) considerably.

[Integrating Public Health Expertise in Research: a Series of Workshops about Vector-Borne and Other Zoonotic Diseases]. / ÖGD-Expertise in die Forschung bringen: eine Workshop-Reihe zu vektorübertragenen und weiteren zoonotischen Erkrankungen.

Research groups must understand the needs and requirements of the public health service to be able to develop tools and strategies for supporting it in risk assessment and risk communication. The zoonotic research consortia RoBoPub, Q-GAPS, TBENAGER and ZooBoCo used the format of workshops to include the expertise of the public health service system in their work. We present the results of three workshops that were held with representatives of the German public health service as part of the annual congress of the Federal Association of Physicians of German Public Health Departments in 2018, 2019 and 2022. Each workshop, held in a world-café format, lasted 90 minutes and had its own thematic focus. In the first workshop, information on the goals, problems, solutions and expectations of the public health service from the research consortia concerning exposure to rodent-borne infections during their occupational and leisure-time activities as well as the use of risk maps was collected. In the second and third workshops, participants developed risk communication strategies based on scenarios of outbreaks and identifications of new risk areas. Each workshop had more than 20 participants, of which at least half worked for local public health authorities. Foremost, participants expected practical, target group-specific material for risk communication from the research groups. According to the experience of most participants, direct contact with the affected groups was essential for risk communication. To raise awareness of the situation and establish contact with the relevant target groups, social media can complement traditional media, especially for hard-to-reach groups. However, their use should be considered and planned carefully. The workshop format was appropriate for integrating the public health expertise in the research activities. The expectations of the public health service on material for risk communication could be translated into a guideline, a risk management plan and pathogen descriptions by the research groups. When integrating the expertise of the public health authorities in their work, research groups should consider how to reach a suitable panel of representatives and how to keep the workload for those at an acceptably low level.

[Viral zoonoses in Germany: a One Health perspective]. / Virale Zoonosen in Deutschland aus der One Health-Perspektive.

The COVID-19 pandemic and the increasing occurrence of monkeypox (mpox) diseases outside Africa have illustrated the vulnerability of populations to zoonotic pathogens. In addition, other viral zoonotic pathogens have gained importance in recent years.This review article addresses six notifiable viral zoonotic pathogens as examples to highlight the need for the One Health approach in order to understand the epidemiology of the diseases and to derive recommendations for action by the public health service. The importance of environmental factors, reservoirs, and vectors is emphasized, the diseases in livestock and wildlife are analyzed, and the occurrence and frequency of diseases in the population are described. The pathogens selected here differ in their reservoirs and the role of vectors for transmission, the impact of infections on farm animals, and the disease patterns observed in humans. In addition to zoonotic pathogens that have been known in Germany for a long time or were introduced recently, pathogens whose zoonotic potential has only lately been shown are also considered.For the pathogens discussed here, there are still large knowledge gaps regarding the transmission routes. Future One Health-based studies must contribute to the further elucidation of their transmission routes and the development of prevention measures. The holistic approach does not necessarily include a focus on viral pathogens/diseases, but also includes the question of the interaction of viral, bacterial, and other pathogens, including antibiotic resistance and host microbiomes.

[Tick-Borne Encephalitis (TBE) - Fundamentals]. / Frühsommer-Meningoenzephalitis (FSME).

Tick-Borne Encephalitis (TBE) - Fundamentals Abstract. There is widespread endemicity of tick-borne encephalitis (TBE) in all German-speaking countries. In most regions there is a gradual increase in incidence and further territorial spread. As a proportion of the cases is not diagnosed and since the clinical course is getting worse with growing age, substantial underreporting occurs particularly in the pediatric and adolescent patient population. Infected ticks are transmitting the TBE virus, a flavivirus, within a few minutes after the bite. After an incubation period of 4 to 28 days uncharacteristic flu-like symptoms usually occur during a first viremic phase. This is followed by a brief asymptomatic interval before a minority of patients suffer of a variety of symptoms associated with damage of different parts of the central nervous system. This often results in permanent neurological injury and in about 1% the clinical course is fatal. To establish a diagnosis, it is essential to suspect the infection and to obtain a history of exposure. Depending on the phase of illness IgM and/or IgG antibodies can be detected in the serum and/or in the cerebrospinal fluid. In the early phase of the infection the TBE virus may be detected by PCR.

Assessing the Quality of Serological Testing in the COVID-19 Pandemic: Results of a European External Quality Assessment (EQA) Scheme for Anti-SARS-CoV-2 Antibody Detection.

External quality assessment (EQA) is a key instrument for achieving harmonization, and thus a high quality, of diagnostic procedures. As reliable test results are crucial for accurate assessment of SARS-CoV-2 infection prevalence, vaccine response, and immunity, and thus for successful management of the ongoing COVID-19 pandemic, the Reference Institute for Bioanalytics (RfB) was the first EQA provider to offer an open scheme for anti-SARS-CoV-2 antibody detection. The main objectives of this EQA were (i) to gain insights into the current diagnostic landscape and the performance of serological tests in Europe and (ii) to provide recommendations for diagnostic improvements. Within the EQA, a blinded panel of precharacterized human serum samples with variable anti-SARS-CoV-2 antibody titers was provided for detection of anti-SARS-CoV-2 IgG, IgA, and IgM antibodies. Across the three distribution rounds in 2020, 284 laboratories from 22 countries reported a total of 3,744 results for anti-SARS-CoV-2 antibody detection using more than 24 different assays for IgG. Overall, 97/3,004 results were false for anti-SARS-CoV-2 IgG, 88/248 for IgA, and 34/124 for IgM. Regarding diagnostic sensitivity and specificity, substantial differences were found between the different assays used, as well as between certified and noncertified tests. For cutoff samples, a drop in the diagnostic sensitivity to 46.3% and high interlaboratory variability were observed. In general, this EQA highlights the current variability of anti-SARS-CoV-2 antibody detection, technical limitations with respect to cutoff samples, and the lack of harmonization of testing procedures. Recommendations are provided to help laboratories and manufacturers further improve the quality of anti-SARS-CoV-2 serological diagnostics.

Tick species from cattle in the Adama Region of Ethiopia and pathogens detected.

Ticks will diminish productivity among farm animals and transmit zoonotic diseases. We conducted a study to identify tick species infesting slaughter bulls from Adama City and to screen them for tick-borne pathogens. In 2016, 291 ticks were collected from 37 bulls in Adama, which were ready for slaughter. Ticks were identified morphologically. Total genomic DNA was extracted from ticks and used to test for Rickettsia spp. with real-time PCR. Species identification was done by phylogenetic analysis using sequencing that targeted the 23S-5S intergenic spacer region and ompA genes. Four tick species from two genera, Amblyomma and Rhipicephalus, were identified. Amblyomma cohaerens was the dominant species (n = 241, 82.8%), followed by Amblyomma variegatum (n = 22, 7.5%), Rhipicephalus pulchellus (n = 19, 6.5%), and Rhipicephalus decoloratus (n = 9, 3.0%). Among all ticks, 32 (11%) were positive for Rickettsia spp. and 15 (5.2%) of these were identified as R. africae comprising at least two genetic clades, occurring in A. variegatum (n = 10) and A. cohaerens (n = 5). The remainder of Rickettsia-positive samples could not be amplified due to low DNA yield. Furthermore, another 15 (5.2%) samples carried other pathogenic bacteria: Ehrlichia ruminantium (n = 9; 3.1%) in A. cohaerens, Ehrlichia sp. (n = 3; 1%) in Rh. pulchellus and A. cohaerens, Anaplasma sp. (n = 1; 0.5%) in A. cohaerens, and Neoehrlichia mikurensis (n = 2; 0.7%) in A. cohaerens. All ticks were negative for Bartonella spp., Babesia spp., Theileria spp., and Hepatozoon spp. We reported for the first time E. ruminatium, N. mikurensis, Ehrlichia sp., and Anaplasma sp. in A. cohaerens. Medically and veterinarily important pathogens were mostly detected from A. variegatum and A. cohaerens. These data are relevant for a One-health approach for monitoring and prevention of tick-borne disease transmission.

The envelope protein of tick-borne encephalitis virus influences neuron entry, pathogenicity, and vaccine protection.

BACKGROUND: Tick-borne encephalitis virus (TBEV) is considered to be the medically most important arthropod-borne virus in Europe. The symptoms of an infection range from subclinical to mild flu-like disease to lethal encephalitis. The exact determinants of disease severity are not known; however, the virulence of the strain as well as the immune status of the host are thought to be important factors for the outcome of the infection. Here we investigated virulence determinants in TBEV infection. METHOD: Mice were infected with different TBEV strains, and high virulent and low virulent TBEV strains were chosen. Sequence alignment identified differences that were cloned to generate chimera virus. The infection rate of the parental and chimeric virus were evaluated in primary mouse neurons, astrocytes, mouse embryonic fibroblasts, and in vivo. Neutralizing capacity of serum from individuals vaccinated with the FSME-IMMUN® and Encepur® or combined were evaluated. RESULTS: We identified a highly pathogenic and neurovirulent TBEV strain, 93/783. Using sequence analysis, we identified the envelope (E) protein of 93/783 as a potential virulence determinant and cloned it into the less pathogenic TBEV strain Torö. We found that the chimeric virus specifically infected primary neurons more efficiently compared to wild-type (WT) Torö and this correlated with enhanced pathogenicity and higher levels of viral RNA in vivo. The E protein is also the major target of neutralizing antibodies; thus, genetic variation in the E protein could influence the efficiency of the two available vaccines, FSME-IMMUN® and Encepur®. As TBEV vaccine breakthroughs have occurred in Europe, we chose to compare neutralizing capacity from individuals vaccinated with the two different vaccines or a combination of them. Our data suggest that the different vaccines do not perform equally well against the two Swedish strains. CONCLUSIONS: Our findings show that two amino acid substitutions of the E protein found in 93/783, A83T, and A463S enhanced Torö infection of neurons as well as pathogenesis and viral replication in vivo; furthermore, we found that genetic divergence from the vaccine strain resulted in lower neutralizing antibody titers in vaccinated individuals.

Rapid Detection of SARS-CoV-2 by Low Volume Real-Time Single Tube Reverse Transcription Recombinase Polymerase Amplification Using an Exo Probe with an Internally Linked Quencher (Exo-IQ).

BACKGROUND: The current outbreak of SARS-CoV-2 has spread to almost every country with more than 5 million confirmed cases and over 300,000 deaths as of May 26, 2020. Rapid first-line testing protocols are needed for outbreak control and surveillance. METHODS: We used computational and manual designs to generate a suitable set of reverse transcription recombinase polymerase amplification (RT-RPA) primer and exonuclease probe, internally quenched (exo-IQ), sequences targeting the SARS-CoV-2 N gene. RT-RPA sensitivity was determined by amplification of in vitro transcribed RNA standards. Assay selectivity was demonstrated with a selectivity panel of 32 nucleic acid samples derived from common respiratory viruses. To validate the assay against full-length SARS-CoV-2 RNA, total viral RNA derived from cell culture supernatant and 19 nasopharyngeal swab samples (8 positive and 11 negative for SARS-CoV-2) were screened. All results were compared to established RT-qPCR assays. RESULTS: The 95% detection probability of the RT-RPA assay was determined to be 7.74 (95% CI: 2.87-27.39) RNA copies per reaction. The assay showed no cross-reactivity to any other screened coronaviruses or respiratory viruses of clinical significance. The developed RT-RPA assay produced 100% diagnostic sensitivity and specificity when compared to RT-qPCR (n = 20). CONCLUSIONS: With a run time of 15 to 20 minutes and first results being available in under 7 minutes for high RNA concentrations, the reported assay constitutes one of the fastest nucleic acid based detection methods for SARS-CoV-2 to date and may provide a simple-to-use alternative to RT-qPCR for first-line screening at the point of need.

Results of the first pilot external quality assessment (EQA) scheme for anti-SARS-CoV2-antibody testing.

Objectives Assessment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection prevalence and immunity is cornerstones in the fight against COVID-19 pandemic. For pandemic control, reliable assays for the detection of anti-SARS-CoV-2 antibodies are required. This pilot external quality assessment (EQA) scheme aimed to independently assess the participants' clinical performance of anti-SARS-CoV-2 testing, to identify shortcomings in clinical practice and to evaluate the suitability of the scheme format. Methods The EQA scheme consisted of eight serum samples with variable reactivity against SARS-CoV-2 intended for the analysis of anti-SARS-CoV-2 immunoglobulin (Ig)G, IgA, and IgM antibodies. Laboratories reported: (1) results for each sample and the respective method, (2) raw data from replicate testing of each sample. Results The 16 selected pilot EQA participants reported 294 interpreted results and 796 raw data results from replicate testing. The overall error rate for the anti-SARS-CoV-2 IgG, IgA, and IgM tests was 2.7, 6.9, and 16.7%, respectively. While the overall diagnostic specificity was rated as very high, sensitivity rates between 67 and 98% indicate considerable quality differences between the manufacturers, especially for IgA and IgM. Conclusions Even the results reported by the small number of participants indicate a very heterogeneous landscape of anti-SARS-CoV-2 serological testing. Differences of available tests and the individual performance of laboratories result in a success rate of 57.1% with one laboratory succeeding for all three antibody-classes. These results are an incentive for laboratories to participate in upcoming open EQA schemes that are needed to achieve a harmonization of test results and to improve serological testing.

Tick burden on European roe deer (Capreolus capreolus) from Saxony, Germany, and detection of tick-borne encephalitis virus in attached ticks.

Southern Germany is known as tick-borne encephalitis (TBE) risk area; however, the north of the country is almost free of human TBE cases. Due to its location in the transition zone between TBE risk areas and areas with only sporadic cases, Saxony is of importance in the surveillance of TBE. Roe deer (Capreolus capreolus), showing high seroprevalence of TBE virus (TBEV) antibodies, are considered to be sentinels for TBE risk assessment. Thus, roe deer could be used as indicators helping to better understand the focality of the TBEV in nature and as a possible source to isolate TBEV. Therefore, the aims of this study were to examine roe deer coats for the presence of ticks to establish the tick burden and to detect the TBEV in attached ticks. One hundred thirty-four roe deer coats were provided by hunters from the Hunting Association in Saxony (August 2017-January 2019). The coats were frozen at - 80 °C and after de-freezing examined on both sides-inside and outside. Attached and nonattached ticks were collected, morphologically identified and tested using real-time RT-PCR for the presence of TBEV. In total, 1279 ticks were found on 48 coats. The predominant species was Ixodes ricinus (99.76%; n = 1276). Three remaining specimens were Ixodes spp. (0.16%, 1 female and 1 nymph) and Dermacentor reticulatus (0.08%, 1 male). The average infestation rate was 26.7 (SD = 69.5), with maximum of 439 ticks per animal. Females were the dominant life stage of ticks (n = 536; 42%), followed by nymphs (n = 397; n = 31.1%), males (n = 175; 13.7%), and larvae (n = 168; 13.2%). Only half of collected ticks were attached (n = 662; 51.8%). TBEV was detected only in one tick out of 1279 tested ticks. It was a female infesting a roe deer from Saxon Switzerland-East Ore Mountain. The results show that the method used in this study is not sufficient as a sentinel marker to predict TBEV spreading in nature. Although previous studies demonstrated the usefulness of serological testing of roe deer in order to trace TBE-endemic regions, using ticks attached to them to get virus isolates is not productive.

Ixodid tick species and two tick-borne pathogens in three areas in the Sudan.

Ticks are important parasites from economic and public health points of view because of their ability to reduce farm animals' productivity and transmit zoonotic diseases. We conducted this cross-sectional study between January and March 2016 and between March and April 2017 to identify tick species in West Darfur, Al-Jazeera, and the River Nile states in the Sudan and to investigate whether these ticks carry Rickettsia spp. and Crimean-Congo hemorrhagic fever (CCHF) virus. In total, 1593 ticks were collected from 207 animals and identified based on morphology or 16S rRNA gene and tested for Rickettsia spp. and CCHF virus either individually or as pools containing 2 to 10 pooled ticks using molecular methods. Overall, 14 tick species belonging to three genera, namely Amblyomma, Hyalomma, and Rhipicephalus, were identified. Hyalomma anatolicum and Rhipicephalus evertsi evertsi were the most frequent ticks. A total of 561 tests comprised of individual or pooled ticks were conducted and 13.7% (77/561) were positive for Rickettsia spp. which were mostly Rickettsia aeschlimannii and R. africae. The highest positivity was noticed among H. rufipes collected from cattle and camels in West Darfur. However, none of the screened Hyalomma ticks harbored CCHF viral RNA. These findings suggest that there might be a risk of zoonotic transmission of Rickettsia spp. by ticks but zoonotic transmission of CCHF virus is apparently doubtful. An in-depth and a country-wide epidemiological study is needed to better understand the dynamic of Rickettsia spp. and CCHF virus in the Sudan.

Canine Leishmaniasis Control in the Context of One Health.

Dogs are the main reservoir of Leishmania infantum and in some countries have been regularly culled as part of government policy to control visceral leishmaniasis. At the 13th Symposium of the Companion Vector-Borne Diseases World Forum in Windsor, UK, March 19-22, 2018, we consolidated a consensus statement regarding the usefulness of dog culling as a means of controlling visceral leishmaniasis. The statement highlighted the futility of culling infected dogs, whether healthy or sick, as a measure to control the domestic reservoir of L. infantum and reduce the risk for visceral leishmaniasis.

Correlation of Severity of Human Tick-Borne Encephalitis Virus Disease and Pathogenicity in Mice.

We compared 2 tick-borne encephalitis virus strains isolated from 2 different foci that cause different symptoms in tick-borne encephalitis patients, from neurologic to mild gastrointestinal symptoms. We compared neuroinvasiveness, neurovirulence, and proinflammatory cytokine response in mice and found unique differences that contribute to our understanding of pathogenesis.

Development of a pan-rickettsial molecular diagnostic test based on recombinase polymerase amplification assay.

Rickettsioses are zoonotic vector-transmitted bacterial infections leading to flu-like symptoms and can progress to severe illness in humans. The gold standard for diagnosis of rickettsial infections is the indirect immunofluorescence assay, a serological method which is not suitable for pathogen identification during the acute phase of the disease. Therefore, several real-time PCR assays were developed. These assays are very sensitive, but require high-equipped laboratories and well-trained personnel. Hence, in this study, a rapid point-of-need detection method was developed to detect all Rickettsia species. The 23S and 16S rRNA genes were targeted to develop a recombinase polymerase amplification (RPA) assay. Both 23S and 16S_RPA assays required between seven to ten minutes to amplify and detect one or ten DNA molecules/reaction, respectively. The 16S_RPA assay detected all tested species, whereas the 23S_RPA assay identified only species of the spotted fever and transitional rickettsial groups. All results were compared with real-time PCR assays directed against the same rickettsial genes. The RPA assays are easy to handle and produced quicker results in comparison to real-time PCRs. Both RPA assays were implemented in a mobile suitcase laboratory to ease the use in rural areas. This method can help to provide rapid management of rickettsial infections.

Tick-borne pathogens in tick species infesting humans in Sibiu County, central Romania.

Romania has a highly diverse tick fauna. Consequently, a high diversity of tick-transmitted pathogens might be a potential threat to humans. However, only a limited number of tick species regularly infest humans, and pathogens present in such species are therefore of particular interest from a medical perspective. In this study, 297 ticks were collected from humans during 2013 and 2014. Ixodes ricinus was the predominant tick species, accounting for 272 specimens or 91.6% of the ticks in the study. Nevertheless, other tick species were also found to infest humans: Dermacentor marginatus constituted 7% of the ticks found on humans (21/297), Haemaphysalis punctata 1% (3/297), and Haemaphysalis concinna 0.3% (1/297). Ticks were tested by PCR for a wide range of tick-borne pathogens. In total, 11.8% of the ticks carried human pathogenic bacteria, while no viral or protozoan pathogens were detected. The most frequently detected pathogen was Rickettsia spp., occurring in 5.4% of the ticks (16/297) and comprising three species: Rickettsia (R.) raoultii, R. monacensis, and R. helvetica. Borrelia s.l. occurred in 3% (9/297) of the ticks. "Candidatus Neoehrlichia mikurensis" occurred in 1.7% (5/297) and Anaplasma phagocytophilum in 1.3% (4/297). Anaplasma bovis was detected in an H. punctata and Borrelia miyamotoi in an I. ricinus. These results point to the need for further studies on the medical importance of tick-borne pathogens in Romania.

Forecasting next season's Ixodes ricinus nymphal density: the example of southern Germany 2018.

The castor bean tick, Ixodes ricinus (L.) (Ixodida: Ixodidae), is the principal vector of pathogens causing tick-borne encephalitis or Lyme borreliosis in Europe. It is therefore of general interest to make an estimate of the density of I. ricinus for the whole year at the beginning of the tick season. There are two necessary conditions for making a successful prediction: a long homogeneous time series of observed tick density and a clear biological relationship between environmental predictors and tick density. A 9-year time series covering the period 2009-2017 of nymphal I. ricinus flagged at monthly intervals in southern Germany has been used. With the hypothesis that I. ricinus density is triggered by the fructification of the European beech 2 years before, the mean annual temperature of the previous year, and the current mean winter temperature (December-February), a forecast of the annual nymphal tick density has been made. Therefore, a Poisson regression model was generated resulting in an explained variance of 93.4% and an error of [Formula: see text] ticks per [Formula: see text] (annual [Formula: see text] collected ticks/[Formula: see text]). An independent verification of the forecast for the year 2017 resulted in 187 predicted versus 180 observed nymphs per [Formula: see text]. For the year 2018 a relatively high number of 443 questing I. ricinus nymphs per [Formula: see text] is forecasted, i.e., a "good" tick year.

Long-term kinetics of Zika virus RNA and antibodies in body fluids of a vasectomized traveller returning from Martinique: a case report.

BACKGROUND: The magnitude of the current Zika virus (ZIKV) epidemic has led to a declaration of a Public Health Emergency of International Concern by the WHO. Findings of viable viral particles in semen for several weeks are corroborating reports of sexual transmission of ZIKV. Serious consequences of a positive diagnostic result particularly in the pregnant patient are calling for precise diagnostic tools also at later time points after infection. Currently, recommendations suggest a diagnostic period of direct viral detection of 5 to 7 days after onset of symptoms in serum or plasma, and up to 3 weeks in urine samples. CASE PRESENTATION: A vasectomized 41-year-old German returning from Martinique presented at the outpatient clinic of the Department for Infectious Diseases and Tropical Medicine, Munich, with subfebrile temperature, rash, malaise, severe retro-orbital pain and occipital lymphadenopathy. The main complaints resolved after ten days without specific treatment. We are reporting on clinical course and results of direct and indirect detection methods of ZIKV in different sample types including whole blood, ejaculate, urine, serum, plasma and saliva samples up to 119 days post symptom onset. Ejaculate samples remained PCR positive for ZIKV until day 77, whole blood samples until day 101. CONCLUSIONS: The case presentation adds to the still limited knowledge of kinetics of detection of ZIKV by direct as well as indirect methods. Here, a complete data set including results from PCR, serology and cell culture is provided allowing an improved evaluation of optimum diagnostic periods for testing a variety of sample types. Moreover, a high viral load of ZIKV RNA was detected in ejaculate of the vasectomized patient. This finding sheds new light on the possible localizations of ZIKV replication in the human male reproductive tract.