Publications by authors named "Hanna K de Jong"

Article Synopsis
  • This systematic review and meta-analysis investigated symptomatic yellow fever breakthrough infections in vaccinated individuals, focusing on cases occurring less than and more than ten years after vaccination.
  • The research reviewed 1975 records, ultimately identifying 37 relevant studies that documented 6951 yellow fever cases, with 537 involving vaccinated patients, primarily from Brazil.
  • A total of 33 confirmed or probable breakthrough cases were found, with two patients severely ill and resulting in death, highlighting a need for ongoing surveillance in vaccinated populations.
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Article Synopsis
  • Clinical trials are essential for determining the safety and effectiveness of drugs and vaccines, but they typically take over ten years; however, recent global health emergencies like COVID-19 have shown that these trials can be accelerated.
  • A study analyzed drugs targeting infectious diseases authorized by the European Medicines Agency from 2012 to 2022, finding a median clinical development time of 7.3 years, but significantly shorter times for COVID-19 (1.3 years) and Ebola (5.5 years).
  • Key factors for faster development included the outbreak context, which reduced time by an average of 5.4 years, and the use of accelerated assessment by the EMA, leading to additional time savings.
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Background: Long-term immunity following yellow fever vaccination remains controversial. We aimed to summarise the literature regarding the long-term protection (≥10 years) conveyed by a single dose of yellow fever vaccination.

Methods: In this systematic review and meta-analysis, we searched 11 databases from database inception to Aug 24, 2023.

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For decades, immunoglobulin preparations have been used to prevent or treat infectious diseases. Since only a few years, monoclonal antibody applications (mAbs) are taking flight and are increasingly dominating this field. In 2014, only two mAbs were registered; end of October 2023, more than ten mAbs are registered or have been granted emergency use authorization, and many more are in (pre)clinical phases.

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Non-timely reporting, selective reporting, or non-reporting of clinical trial results are prevalent and serious issues. WHO mandates that summary results be available in registries within 12 months of study completion and published in full text within 24 months. However, only a limited number of clinical trials in infectious diseases, including those done during the COVID-19 pandemic, have their results posted on ClinicalTrials.

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Article Synopsis
  • Earlier research indicated distinct blood changes in African patients with schistosomiasis, suggesting that full blood counts (FBC) could aid in diagnosing the disease in travelers and migrants.
  • A study reviewed patient records from seven travel clinics in Europe, analyzing FBC data of 382 subjects, focusing on changes among returned travelers and migrants.
  • The findings revealed significant decreases in various blood cell counts for returned travelers, particularly in females, and although migrants had somewhat similar profiles, they exhibited notably lower platelet and white blood cell counts; thus, FBC is not reliable for diagnosing schistosomiasis.
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Background: Coronavirus disease 2019 (COVID-19)-induced mortality occurs predominantly in older patients. Several immunomodulating therapies seem less beneficial in these patients. The biological substrate behind these observations is unknown.

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According to current guidelines, atovaquone-proguanil (AP) malaria chemoprophylaxis should be taken once daily starting one day before travel and continued for seven days post-exposure. However, drug-sparing regimens, including discontinuing AP after leaving malaria-endemic areas are cost-saving and probably more attractive to travelers, and may thus enhance adherence. AP has causal prophylactic effects, killing malaria parasites during the hepatic stage.

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Background: Atovaquone/proguanil (AP) is a highly effective malaria chemoprophylaxis combination. According to current guidelines, AP is taken once daily during, and continued for seven days post exposure. A systematic review by Savelkoel et al.

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Background: Experimental murine models and human challenge studies of Typhi infection have suggested that the gut microbiome plays an important protective role against the development of typhoid fever. Anaerobic bacterial communities have been hypothesized to mediate colonization resistance against species by producing short-chain fatty acids, yet the composition and function of the intestinal microbiota in human patients with typhoid fever remain ill defined.

Methods: We prospectively collected fecal samples from 60 febrile patients admitted to Chittagong Medical College Hospital, Bangladesh, with typhoid fever or nontyphoidal febrile illness and from 36 healthy age-matched controls.

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The Gram-negative intracellular pathogen is the causative agent of melioidosis, an important cause of sepsis in Southeast Asia. Recognition of pathogen-associated molecular patterns by Toll-like receptors (TLRs) is essential for an appropriate immune response during pathogen invasion. In patients with melioidosis, TLR5 is the most abundantly expressed TLR, and a hypofunctional TLR5 variant has been associated with improved survival.

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Intravesical bacillus Calmette-Guérin (BCG) is widely used for high-risk, non-muscle-invasive bladder cancer. This report describes four cases that illustrate the spectrum of BCG-induced complications, varying from granulomatous prostatitis to sepsis. There is considerable debate regarding whether inflammation or infection is the predominant mechanism in the pathogenesis of BCG disease.

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Objectives: Typhoid fever caused by Salmonella Typhi remains a major burden worldwide. Gastrointestinal bleeding can be seen in up to 10 percent of patients and may be fatal. The coagulopathy, which may be the driver of this severe complication in patients with typhoid fever, however is ill defined.

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Background: Typhoid fever, caused by the intracellular pathogen Salmonella (S.) enterica serovar Typhi, remains a major cause of morbidity and mortality worldwide. Granzymes are serine proteases promoting cytotoxic lymphocytes mediated eradication of intracellular pathogens via the induction of cell death and which can also play a role in inflammation.

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Objectives: The diagnosis of typhoid fever is a challenge. Aiming to develop a typhoid diagnostic we measured antibody responses against Salmonella Typhi (S. Typhi) protein antigens and the Vi polysaccharide in a cohort of Bangladeshi febrile patients.

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Typhi is the causative agent of typhoid. Typhoid is diagnosed by blood culture, a method that lacks sensitivity, portability and speed. We have previously shown that specific metabolomic profiles can be detected in the blood of typhoid patients from Nepal (Näsström et al.

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Background: Melioidosis, caused by the gram-negative bacterium Burkholderia pseudomallei, is a common cause of community-acquired sepsis in Southeast Asia and Northern Australia. The NLRP3 inflammasome and its downstream product interleukin-1 beta (IL-1β) have been proposed to play crucial roles in melioidosis. In this study, we characterized the role of IL-1β more closely and we assessed its therapeutic potential.

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Background: Fever is a common cause of hospital admission in Bangladesh but causative agents, other than malaria, are not routinely investigated. Enteric fever is thought to be common.

Methods: Adults and children admitted to Chittagong Medical College Hospital with a temperature of ≥38.

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Background: Triggering receptor expressed on myeloid cells (TREM) -1 and TREM-2 are key regulators of the inflammatory response that are involved in the clearance of invading pathogens. Melioidosis, caused by the "Tier 1" biothreat agent Burkholderia pseudomallei, is a common form of community-acquired sepsis in Southeast-Asia. TREM-1 has been suggested as a biomarker for sepsis and melioidosis.

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Background: Neutrophil extracellular traps (NETs) are a central player in the host response to bacteria: neutrophils release extracellular DNA (nucleosomes) and neutrophil elastase to entrap and kill bacteria. We studied the role of NETs in Burkholderia pseudomallei infection (melioidosis), an important cause of Gram-negative sepsis in Southeast Asia.

Methods: In a prospective observational study, circulating nucleosomes and neutrophil elastase were assayed in 44 patients with Gram-negative sepsis caused by B.

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Objective: To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh.

Methods: Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert(®) blood cultures and real-time PCR to detect Salmonella enterica Typhi and Paratyphi A and assays for Rickettsia, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test-it™ Typhoid IgM lateral flow assay detecting IgM antibodies against S.

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Background: Typhoid fever, caused by the Gram-negative bacterium Salmonella enterica serovar Typhi, is a major cause of community-acquired bacteremia and death worldwide. S100A8 (MRP8) and S100A9 (MRP14) form bioactive antimicrobial heterodimers (calprotectin) that can activate Toll-like receptor 4, promoting lethal, endotoxin-induced shock and multi-organ failure. We aimed to characterize the expression and function of S100A8/A9 in patients with typhoid fever and in a murine invasive Salmonella model.

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Background: The inflammasome is an intracellular protein complex triggered by exposure to intracellular pathogens, its components or other endogenous proteins. It leads to the activation of and subsequent release of proinflammatory cytokines such as IL-1β and IL-18. S.

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