Search results for " Tropical"

The association between respiratory tract infection incidence and localised meningitis epidemics: an analysis of high-resolution surveillance data fr…

2017

AbstractMeningococcal meningitis epidemics in the African meningitis belt consist of localised meningitis epidemics (LME) that reach attack proportions of 1% within a few weeks. A meningococcal serogroup A conjugate vaccine was introduced in meningitis belt countries from 2010 on, but LME due to other serogroups continue to occur. The mechanisms underlying LME are poorly understood, but an association with respiratory pathogens has been hypothesised. We analysed national routine surveillance data in high spatial resolution (health centre level) from 13 districts in Burkina Faso, 2004–2014. We defined LME as a weekly incidence rate of suspected meningitis ≥75 per 100,000 during ≥2 weeks; and…

Varicella vaccination as useful strategy for reducing the risk of varicella-related hospitalizations in both vaccinated and unvaccinated cohorts (Ita…

2020

The present study summarizes evidences of the impact that varicella vaccination (VV) introduction and coverage can have on varicella attributable hospitalization rates.A retrospective observational study was carried out by considering hospital discharge records and VV coverage at 24 months collected from 2003 to 2018 by the Italian Ministry of Health. All hospitalizations records reporting an ICD-9 CM 052.X code as the principal diagnosis or any of the five secondary diagnoses were considered as related to varicella. The hospitalization rate reduction was evaluated by calculating average annual percent change (AAPC) through joint-point analysis.Hospitalization rates showed a decreasing tren…

2019

Background Congenital Toxoplasmosis (CT) can have severe consequences. France, Austria, and Slovenia have prenatal screening programs whereas some other countries are considering universal screening to reduce congenital transmission and severity of infection in children. The efficiency of such programs is debated increasingly as seroprevalence among pregnant women and incidence of congenital toxoplasmosis show a steady decrease. In addition, uncertainty remains regarding the effectiveness of pre- and postnatal treatments. Method To identify cost-effective strategies, prenatal and neonatal screenings were compared using a decision-analytic model based on French guidelines and current knowled…

Extensive Antibiotic and Antimalarial Prescription Rate among Children with Acute Febrile Diseases in the Lake Victoria Region, Tanzania

2021

Abstract Objectives Acute mosquito-borne febrile diseases pose a threat to children in the Sub-Saharan-Africa with ∼272 000 children dying worldwide from malaria in 2018. Although the awareness for malaria in this area has increased due to improved health education, the apparent decline of actual malaria cases has not affected clinical practice significantly. This study collected clinical and epidemiologic data of children presenting with acute febrile diseases in order delineate their diagnostic and therapeutic management. Methods A hospital-based cross-sectional clinical study was conducted at the Sekou Toure Regional Referral Hospital in Tanzania. Children between 1 month and 12 years of…

Mathematical models for the management of helminth parasites: from biological processes to the evolution of anthelmintic resistance

2010

International audience; Helminth parasitic diseases are mainly controlled by anthelmintic treatments, but control schemes are now threatened by the large development of anthelmintic resistance. Integrated parasite management needs to be developed but processes underpinning parasite population dynamics and resistant gene evolution are still lacking. Here, we review the mathematical models that have been developed to understand the evolution of anthelmintic resistance in host-helminth parasite models (intestinal helminth parasites of herbivores and human soil-transmitted helminths). A first part is dedicated to generic models that allowed the understanding of processes underlying host-helmint…

One-step synthesis, crystallographic studies and antimicrobial activity of new 4-diazopyrazole derivatives

1996

Summary A number of new 4-diazopyrazole derivatives were prepared by the reaction of 1- R -3-methyl-5(R 1 -substituted)benzamidopyrazoles with a sevenfold excess of nitrous acid in acetic medium. The compounds were tested for activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus faecalis, Listeria monocytogenes, Candida albicans, Candida tropicalis and Paecilomyces varioti . The highest microbial susceptibility was shown by Gram-positive bacteria, with minimum inhibitory concentrations (MIC) in the range 0.5–12.5 μg/mL. For S aureus the R 1 substituents were screened utilizing the Topliss operational scheme. The 4-nitro g…

TLR4 abrogates the Th1 immune response through IRF1 and IFN-β to prevent immunopathology during L. infantum infection

2020

A striking feature of human visceral leishmaniasis (VL) is chronic inflammation in the spleen and liver, and VL patients present increased production levels of multiple inflammatory mediators, which contribute to tissue damage and disease severity. Here, we combined an experimental model with the transcriptional profile of human VL to demonstrate that the TLR4-IFN-β pathway regulates the chronic inflammatory process and is associated with the asymptomatic form of the disease. Tlr4-deficient mice harbored fewer parasites in their spleen and liver than wild-type mice. TLR4 deficiency enhanced the Th1 immune response against the parasite, which was correlated with an increased activation of de…

Experimental inhibition of nitric oxide increases Plasmodium relictum (lineage SGS1) parasitaemia.

2012

7 pages; International audience; Malaria is a widespread vector-borne disease infecting a wide range of terrestrial vertebrates including reptiles, birds and mammals. In addition to being one of the most deadly infectious diseases for humans, malaria is a threat to wildlife. The host immune system represents the main defence against malaria parasites. Identifying the immune effectors involved in malaria resistance has therefore become a major focus of research. However, this has mostly involved humans and animal models (rodents) and how the immune system regulates malaria progression in non-model organisms has been largely ignored. The aim of the present study was to investigate the role of…

Sialotranscriptomics of the argasid tick ornithodoros moubata along the trophogonic cycle

2021

32 páginas, 8 tablas, 6 figuras

Extracellular vesicles from parasitic helminths contain specific excretory/secretory proteins and are internalized in intestinal host cells.

2012

The study of host-parasite interactions has increased considerably in the last decades, with many studies focusing on the identification of parasite molecules (i.e. surface or excretory/secretory proteins (ESP)) as potential targets for new specific treatments and/or diagnostic tools. In parallel, in the last few years there have been significant advances in the field of extracellular vesicles research. Among these vesicles, exosomes of endocytic origin, with a characteristic size ranging from 30-100 nm, carry several atypical secreted proteins in different organisms, including parasitic protozoa. Here, we present experimental evidence for the existence of exosome-like vesicles in parasitic…