Publications by authors named "Ralf M Hagen"

Contrawise to mosquitoes, there is no country-wide long-term surveillance of ticks in Germany, leading to large gaps in coverage for distribution data. Here we report on results from two consecutive tick studies in northern Rhineland-Palatinate, western Germany, conducted in 2022 and 2023. In 2022, a new focus of the ornate sheep tick Dermacentor marginatus was detected at a military training area east of Coblenz ("Schmidtenhöhe") which is partially managed as a nature reserve where old races of cattle and horses are grazing.

View Article and Find Full Text PDF

Filtering face piece (FFP) masks according to EN 149 are essential components of personal protective equipment against biological agents from an occupational health and hospital hygiene perspective. Therefore, shortages due to increased demand or supply bottlenecks can lead to staff threats due to the risk of infection. To determine whether FFP masks could be made reusable in a hospital setting, a thermal reprocessing concept (steam at 105 °C with a holding phase of 10 min) was evaluated in a bed reprocessing chamber.

View Article and Find Full Text PDF
Article Synopsis
  • - The study aimed to identify and characterize drug-resistant bacterial pathogens from a war-injured patient in Ukraine by analyzing samples from various body sites during hospital admission screening.
  • - Researchers performed bacterial identification, susceptibility tests, and genetic sequencing to reveal seven distinct Gram-negative bacteria, all resistant to carbapenems, with some also resistant to other crucial antibiotics but susceptible to colistin.
  • - The findings highlighted the presence of diverse clones of multidrug-resistant pathogens with various resistance genes, underscoring the need for effective infection control measures in healthcare settings.
View Article and Find Full Text PDF
Article Synopsis
  • Fungal infections pose significant health risks, especially for individuals with HIV in tropical regions, but data on their prevalence is limited, particularly in Ghana.
  • The study investigates the presence of specific fungi in the gastrointestinal tracts of Ghanaian patients using real-time PCR assays to analyze stool samples from both HIV-positive individuals and controls.
  • Results showed that the targeted fungi were unlikely to be part of the gut microbiota in these populations, suggesting that their detection should not be seen as normal flora and has implications for public health screening strategies.
View Article and Find Full Text PDF
Article Synopsis
  • - The study focuses on the health challenges faced by the indigenous Wiwas of Colombia, particularly concerning a high prevalence of infectious diseases and suspected gaps in their medical treatment.
  • - Data was collected from 2017 to 2018, evaluating local diagnoses using the ICD-10 classification system to identify the types of diseases present and assess the adequacy of medications provided by the indigenous health provider Dusakawi.
  • - Findings revealed that a significant majority of diseases (88%) cannot be adequately treated with the current medications, highlighting the need for improved medical supplies and awareness of neglected diseases in this indigenous community.
View Article and Find Full Text PDF

Multiple microbial detections in stool samples of indigenous individuals suffering from chronic gastroenteric disorder of a likely infectious origin, characterized by recurring diarrhea of variable intensity, in the rural north-east of Colombia are common findings, making the assignment of etiological relevance to individual pathogens challenging. In a population of 773 indigenous people from either the tribe Wiwa or Kogui, collider bias analysis was conducted comprising 32 assessed microorganisms including 10 bacteria ( spp., spp.

View Article and Find Full Text PDF

: For indigenous people in Colombia, high infection rates with Chagas disease (CD) are known. : In 2018 and 2020, nine villages were screened for CD. CD-positive patients could enter a drug observed treatment.

View Article and Find Full Text PDF

Indigenous people live in remote areas of Colombia. Multiple infections with bacteria, protozoa and/or helminths are common, as well as colonization in various forms. This study focused on the question of whether and to what extent various pathogens interact with each other.

View Article and Find Full Text PDF

Medical complications during pregnancy have been frequently reported from Western Africa with a particular importance of infectious complications. Placental tissue can either become the target of infectious agents itself, such as, e.g.

View Article and Find Full Text PDF

Potential etiological relevance for gastroenteric disorders including diarrhea has been assigned to . However, standard routine diagnostic algorithms for stool samples of patients with diarrhea are rarely adapted to the detection of this pathogen and so, is likely to go undetected unless it is specifically addressed, e.g.

View Article and Find Full Text PDF

Extended spectrum beta-lactamases (ESBL) are frequently found in Enterobacterales isolates from Western Africa. However, information on the molecular epidemiology of regional ESBL-positive Enterobacterales strains is scarce. In order to provide epidemiological information, ESBL-positive isolates from stool samples of European soldiers with diarrhea deployed to a field camp in Mali were subjected to whole-genome sequencing (Illumina MiSeq and Oxford Nanopore MinION) and antimicrobial susceptibility testing.

View Article and Find Full Text PDF

Phlebotomine sand flies of the genus Sergentomyia are considered to be of minor importance as vectors of Leishmania parasites pathogenic to humans, but are known to transmit lizard parasites of the subgenus Sauroleishmania, including L. (S.) adleri.

View Article and Find Full Text PDF

An Indigenous agropastoralist population called the Wiwa from the Sierra Nevada de Santa Marta, in North-East Colombia, shows high rates of gastrointestinal infections. Chronic gut inflammatory processes and dysbiosis could be a reason, suggesting an influence or predisposing potential of the gut microbiome composition. The latter was analyzed by 16S rRNA gene amplicon next generation sequencing from stool samples.

View Article and Find Full Text PDF

Colonization and infection with bacteria with acquired antibiotic resistance are among the risks for soldiers on international deployments. Enterobacterales with resistance against third-generation cephalosporines are amongst the most frequently imported microorganisms. To contribute to the scarcely available epidemiological knowledge on deployment-associated resistance migration, we assessed the molecular epidemiology of third-generation cephalosporine-resistant isolated between 2007 and 2016 from German soldiers after deployments, with a particular focus on the African Sahel region.

View Article and Find Full Text PDF

Intestinal amoebiasis in a 35-year-old German patient with a 3 weeks travel history in Indonesia was initially misidentified as non-steroidal anti-inflammatory-drug associated colitis in colonoscopy and histopathological analysis. Furthermore, initial stool examination by microscopy and Entamoeba faecal antigen ELISA did not reveal any protozoan infection. When cessation of non-steroidal anti-inflammatory drug (NSAID) use and mesalazine treatment did not lead to clinical improvement, the patient presented to a specialist for tropical diseases.

View Article and Find Full Text PDF

Background: Salmonella enterica is among the major burdens for public health at global level. Typing of salmonellae below the species level is fundamental for different purposes, but traditional methods are expensive, technically demanding, and time-consuming, and therefore limited to reference centers. Fourier transform infrared (FTIR) spectroscopy is an alternative method for bacterial typing, successfully applied for classification at different infra-species levels.

View Article and Find Full Text PDF

The suitability of incubated blood culture material for forensic molecular malaria diagnosis was assessed for non-endemic settings for cases in which the differential diagnosis malaria was initially overlooked. For the proof-of-principle assessment, residual blood culture materials from febrile patients from tropical Ghana were investigated by real-time PCR and compared with available historic microscopic results. In 2114 samples, for which microscopical results and real-time PCR results were available, microscopical results comprised 711 detections, 7 detections, 1 microscopically not-further-discriminable spp.

View Article and Find Full Text PDF

The study was performed to provide an overview of the molecular epidemiology of carbapenem-resistant in Afghanistan isolated by the German military medical service during the Afghanistan conflict. A total of 18 isolates were collected between 2012 and 2018 at the microbiological laboratory of the field hospital in Camp Marmal near Mazar-e Sharif, Afghanistan, from Afghan patients. The isolates were subjected to phenotypic and genotypic differentiation and antimicrobial susceptibility testing as well as to a core genome multi-locus sequence typing (cgMLST) approach based on whole-genome next-generation sequence (wgNGS) data.

View Article and Find Full Text PDF

Rickettsiae may cause febrile infections in humans in tropical and subtropical regions. From Madagascar, no molecular data on the role of rickettsioses in febrile patients are available. Blood samples from patients presenting with fever in the area of the capital Antananarivo were screened for the presence of rickettsial DNA.

View Article and Find Full Text PDF

is a coccidian parasite associated with acute or chronic gastroenteritis in immunocompromised patients. Dissatisfactory sensitivity of microscopy as the diagnostic standard approach has been described. Here, we comparatively evaluated two real-time PCRs targeting ribosomal RNA gene sequences of in stool in a test comparison without a reference standard applying latent class analysis.

View Article and Find Full Text PDF
Article Synopsis
  • PCR (Polymerase Chain Reaction) testing from serum is a less invasive diagnostic method for visceral leishmaniasis compared to more invasive techniques like bone marrow examination.
  • A study compared three PCR tests targeting different genetic materials, finding that kinetoplast DNA-PCR was the most sensitive (93.3%) for diagnosing the disease in initial samples.
  • All PCR tests showed 100% specificity in samples from individuals without leishmaniasis, confirming kinetoplast DNA-PCR as an effective method for diagnosis and post-therapy follow-ups.
View Article and Find Full Text PDF

The application of modern PCR approaches for the diagnosis of bacterial gastrointestinal pathogens is on the rise due to their rapidly available results combined with high sensitivity. While multiple studies describe the ongoing implementation of this technique for routine diagnostic purposes in laboratories in Western industrialized countries, reports on successful and also sustainable respective approaches in resource-poor tropical settings are still scarce. In order to shed light on potential reasons for this marked discrepancy, this narrative review summarizes identified challenges for the application of diagnostic PCR targeting bacterial gastrointestinal pathogens from stool samples in the tropics.

View Article and Find Full Text PDF

Typhoidal and para-typhoidal are major causes of bacteraemia in resource-limited countries. Diagnostic alternatives to laborious and resource-demanding serotyping are essential. Fourier transform infrared spectroscopy (FTIRS) is a rapidly developing and simple bacterial typing technology.

View Article and Find Full Text PDF

At the Bundeswehr Hospitals of Hamburg and Westerstede, patients repatriated from subtropical war and crisis zones of Northern Africa and the Middle East were medically treated, including microbiological assessment. Within a six-year interval, 16 spp. strains, including 14 (Ab) isolates with resistance against carbapenems and origins in Afghanistan ( = 4), Iraq ( = 2), Libya ( = 2), and Syria ( = 8) were collected.

View Article and Find Full Text PDF