Publications by authors named "Kremsner P"

Antibody glycosylation patterns can affect antibody functionality and thereby contribute to protection against invading pathogens. During pregnancy, maternal antibodies can be transferred through the placenta and contribute to modulating both the mother's and her child's immune responses. Although several studies of IgG glycosylation during pregnancy have been carried out, very few cohorts studied were from sub-Saharan Africa, where exposure to microorganisms and parasites is high.

View Article and Find Full Text PDF

Background: SARS-CoV-2 has been associated with a higher proportion of asymptomatic infections and lower mortality in sub-Saharan Africa than high-income countries. However, there is currently a lack of data on cellular immune responses to SARS-CoV-2 in people living in Africa compared with people in high-income regions of the world. We aimed to assess geographical variation in peripheral and mucosal immune responses.

View Article and Find Full Text PDF
Article Synopsis
  • The Prime-2-CoV_Beta is a new COVID-19 vaccine designed to target the SARS-CoV-2 spike and nucleocapsid antigens, and was tested in a phase I clinical trial involving 60 healthy adults in Germany from June 2022 to June 2023.
  • The trial showed that the vaccine had a good safety profile with only mild to moderate side effects, such as pain at the injection site, fatigue, and headache, and no serious adverse events were reported.
  • Immunization resulted in strong immune responses, particularly at higher doses, leading to significant increases in antibodies against SARS-CoV-2 and its variants, indicating the vaccine's potential for broader protection
View Article and Find Full Text PDF

Background: Insecticides are a crucial component of vector control. However, resistance constitute a threat on their efficacy and the gains obtained over the years through malaria vector control. In Gabon, little data on phenotypic insecticide resistance in Anopheles vectors are published, compromising the rational implementation of resistance management strategies.

View Article and Find Full Text PDF

Objectives: Despite evidence of praziquantel's (PZQ) safety for treating schistosomiasis in pregnancy, many countries withhold treatment. Only two randomized controlled trials have investigated PZQ in pregnancy, none involving Schistosoma haematobium.

Methods: Pregnant women during the second trimester in Lambaréné (Gabon) were screened for S.

View Article and Find Full Text PDF
Article Synopsis
  • The PfSPZ Vaccine shows promise as a malaria vaccine, effectively providing sterile protection in both malaria-naïve and exposed adults, relying on immune responses to early liver-stage parasites.
  • A study involving 21 Tanzanian adults analyzed their immune responses to the vaccine and subsequent malaria infection, revealing robust IgG and IgM reactions to specific protein targets, regardless of HIV infection status.
  • The findings highlight PfMSP5 as a significant target for vaccine-induced immunity, indicating that protecting against malaria might be possible without interference from HIV, and underscoring the need for further exploration of this immunogen.
View Article and Find Full Text PDF
Article Synopsis
  • * A study in Vietnam involving 330 patients compared the BioFire FilmArray Meningitis/Encephalitis (FAME) Panel to traditional diagnostic methods, with FAME showing an 87% agreement rate and detecting 19% of specimens.
  • * While FAME offers rapid pathogen detection, it's not a complete replacement for traditional methods and should be tailored to local disease patterns to improve healthcare outcomes.
View Article and Find Full Text PDF

Unlabelled: Malaria rapid diagnostic tests (RDTs), which detect (Pf)-specific histidine-rich protein-2 (HRP2), have increasing importance for the diagnosis and control of malaria, especially also in regions where routine diagnosis by microscopy is not available. HRP2-based RDTs have a similar sensitivity to expert microscopy, but their reported low specificity can lead to high false positivity rates, particularly in high-endemic areas. Despite the widespread use of RDTs, models investigating the dynamics of HRP2 clearance following Pf treatment focus rather on short-term clearance of the protein.

View Article and Find Full Text PDF

Purpose: The consequent use of malaria rapid diagnostic tests (RDTs) preceding a treatment decision has improved the global management of malaria. A combination RDT, including an inflammation marker to potentially guide antibiotic prescription, could improve the management of acute febrile illness (AFI).

Methods: We performed a prospective, cross-sectional study in Gabon evaluating the STANDARD Malaria/CRP DUO (S-DUO) RDT.

View Article and Find Full Text PDF

Background: Unlike adults, children experienced stronger and longer vector replication in plasma and shedding in saliva following rVSVΔG-ZEBOV-GP vaccination. The resulting risks of immunosuppression or immune hyperactivation leading to increased Adverse Events (AEs) and altered antibody responses are concerns that have been addressed in the present manuscript.

Methods: Children aged 1-12 years living in Gabon received either rVSVΔG-ZEBOV-GP (ERVEBO®) vaccine or the varicella-zoster virus (VZV) vaccine (VZV).

View Article and Find Full Text PDF

Background And Objectives: Point-of-care testing using nonsputum samples like serum or plasma proteins can improve tuberculosis (TB) patients access to a definitive diagnosis, especially in resource-constrained and remote areas. Recently, approximately 400 proteins were identified as playing a role in the pathogenesis of TB, offering a translational clinical research repository for TB. In a previous manuscript, we proved the potential use of these proteins for point-of-care testing for active TB diagnosis.

View Article and Find Full Text PDF

Cellular metabolism is a key determinant of immune cell function. Here we found that CD14 monocytes from Sub-Saharan Africans produce higher levels of IL-10 following TLR-4 stimulation and are bioenergetically distinct from monocytes from Europeans. Through metabolomic profiling, we identified the higher IL-10 production to be driven by increased baseline production of NADPH oxidase-dependent reactive oxygen species, supported by enhanced pentose phosphate pathway activity.

View Article and Find Full Text PDF

Immunization through repeated direct venous inoculation of Plasmodium falciparum (Pf) sporozoites (PfSPZ) under chloroquine chemoprophylaxis, using the PfSPZ Chemoprophylaxis Vaccine (PfSPZ-CVac), induces high-level protection against controlled human malaria infection (CHMI). Humoral and cellular immunity contribute to vaccine efficacy but only limited information about the implicated Pf-specific antigens is available. Here, we examined Pf-specific antibody profiles, measured by protein arrays representing the full Pf proteome, of 40 placebo- and PfSPZ-immunized malaria-naïve volunteers from an earlier published PfSPZ-CVac dose-escalation trial.

View Article and Find Full Text PDF

Background: More than 20 million people are infected with L. loa, and around 40 million live in high or intermediate-risk areas in West- and Central Africa. Although loiasis is associated with significant morbidity and excess mortality, little is known about the perception of loiasis by affected communities.

View Article and Find Full Text PDF

Vaccination of malaria-naive volunteers with a high dose of Plasmodium falciparum sporozoites chemoattenuated by chloroquine (CQ) (PfSPZ-CVac [CQ]) has previously demonstrated full protection against controlled human malaria infection (CHMI). However, lower doses of PfSPZ-CVac [CQ] resulted in incomplete protection. This provides the opportunity to understand the immune mechanisms needed for better vaccine-induced protection by comparing individuals who were protected with those not protected.

View Article and Find Full Text PDF

Snakebite envenoming (SBE) is a neglected tropical disease (NTD). Community-based studies from sub-Saharan Africa are urgently required as data on the incidence are scarce. This study aimed to determine the lifetime prevalence of snakebites in rural Gabon by preparing the conduct of a larger regional survey.

View Article and Find Full Text PDF

Following a 2-week trip to Kazakhstan, a 42-year-old woman presented at the emergency department in Germany with fever, headache, nausea, and neurological symptoms. An infection with Plasmodium falciparum was rapidly diagnosed. The patient was immediately treated with intravenous artesunate and transferred to an intensive care unit.

View Article and Find Full Text PDF

Background: While the gut microbiome modulates the pathogenesis of enteric viruses, how infections caused by rotavirus A (RVA), with or without diarrhoea, alter the gut microbiota has been sparsely studied.

Methods: From a cohort of 224 vaccine naïve Gabonese children with and without diarrhoea (n = 177 and n = 67, respectively), 48 stool samples were analysed: (i) RVA with diarrhoea (n = 12); (ii) RVA without diarrhoea (n = 12); (iii) diarrhoea without RVA (n = 12); (iv) healthy controls without diarrhoea and RVA (n = 12). The 16S rRNA metabarcoding using Oxford Nanopore sequencing data was analysed for taxonomic composition, abundance, alpha and beta diversity, and metabolic pathways.

View Article and Find Full Text PDF
Article Synopsis
  • Helminthiasis is a significant public health issue in certain areas, and this study aimed to evaluate the safety and effectiveness of three different anthelmintic drug combinations in treating infections in children aged 2-17 years.
  • A total of 400 mg of albendazole was administered on the first and third days, with different drugs (albendazole, mebendazole, and pyrantel) given on the second day, and effectiveness was measured by cure rates and egg reduction rates at 3 and 6 weeks post-treatment.
  • Results showed that the combination with albendazole (arm A) had the highest effectiveness at 3 weeks, while all treatments were safe with only mild side effects, but concerns remain
View Article and Find Full Text PDF

Background: A human hookworm vaccine is being developed to protect children against iron deficiency and anaemia associated with chronic infection with hookworms. Necator americanus aspartic protease-1 (Na-APR-1) and N americanus glutathione S-transferase-1 (Na-GST-1) are components of the blood digestion pathway critical to hookworm survival in the host. Recombinant Na-GST-1 and catalytically inactive Na-APR-1 (Na-APR-1[M74]) adsorbed to Alhydrogel were safe and immunogenic when delivered separately or co-administered to adults in phase 1 trials in non-endemic and endemic areas.

View Article and Find Full Text PDF

Objectives: We investigated the diversity and dynamics of Plasmodium infection in serially collected samples from asymptomatic participants of a clinical trial assessing the efficacy and safety of ivermectin in Gabon. We checked whether the baseline sample reflected the P. falciparum genotype and Plasmodium species diversity seen over 7 days of follow-up.

View Article and Find Full Text PDF

Background: The parasitic disease loiasis is associated with significant morbidity and mortality. Individuals with hyper-microfilaremia (greater than 20,000 microfilariae per mL of blood) may suffer from serious treatment-related or spontaneous adverse events. Diagnosing loiasis remains complex and primarily relies on direct parasite detection.

View Article and Find Full Text PDF