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The Lancet. Infectious Diseases Jan 2020Creutzfeldt-Jakob disease (CJD) is a fatal disease presenting with rapidly progressive dementia, and most patients die within a year of clinical onset. CJD poses a...
Creutzfeldt-Jakob disease (CJD) is a fatal disease presenting with rapidly progressive dementia, and most patients die within a year of clinical onset. CJD poses a potential risk of iatrogenic transmission, as it can incubate asymptomatically in humans for decades before becoming clinically apparent. In this Review, we sought evidence to understand the current iatrogenic risk of CJD to public health by examining global evidence on all forms of CJD, including clinical incidence and prevalence of subclinical disease. We found that although CJD, particularly iatrogenic CJD, is rare, the incidence of sporadic CJD is increasing. Incubation periods as long as 40 years have been observed, and all genotypes have now been shown to be susceptible to CJD. Clinicians and surveillance programmes should maintain awareness of CJD to mitigate future incidences of its transmission. Awareness is particularly relevant for sporadic CJD, which occurs in older people in whom clinical presentation could resemble rapidly developing dementia.
Topics: Adult; Aged; Aged, 80 and over; Creutzfeldt-Jakob Syndrome; Female; Humans; Iatrogenic Disease; Incidence; Infectious Disease Incubation Period; Male; Middle Aged; Prevalence; Risk Assessment; Young Adult
PubMed: 31876504
DOI: 10.1016/S1473-3099(19)30615-2 -
European Journal of Obstetrics,... Apr 2021Herpes Simplex virus (HSV) infection is one of the most common sexually transmitted infections among women of the reproductive age. It is estimated to affect about 2-3%... (Review)
Review
Herpes Simplex virus (HSV) infection is one of the most common sexually transmitted infections among women of the reproductive age. It is estimated to affect about 2-3% of pregnant women. Vertical transmission during pregnancy is rare occurring in less than 1% of cases but for those with active lesions or shedding the virus asymptomatically the risk of vertical transmission intrapartum is high. Neonates with HSV may develop severe consequences such as disseminated, central nervous system and skin, eye mouth/mucous disease or suffer mortality. A high index of suspicion, timely diagnosis and institution of appropriate treatment during acute and recurrent episodes will reduce the risk of vertical transmission and therefore neonatal consequences. Routine screening for HSV in pregnancy is not recommended. This review provides an overview of HSV in pregnancy, diagnosis and management especially around unique scenarios such as prelabour preterm rupture of fetal membranes and presentation with active disease in labour.
Topics: Antiviral Agents; Female; Herpes Genitalis; Herpes Simplex; Humans; Infant, Newborn; Infectious Disease Transmission, Vertical; Mass Screening; Pregnancy; Pregnancy Complications, Infectious; Sexually Transmitted Diseases
PubMed: 33581405
DOI: 10.1016/j.ejogrb.2021.01.055 -
Current Medicinal Chemistry 2020Endophytes represent a complex community of microorganisms colonizing asymptomatically internal tissues of higher plants. Several reports have shown that endophytes... (Review)
Review
BACKGROUND
Endophytes represent a complex community of microorganisms colonizing asymptomatically internal tissues of higher plants. Several reports have shown that endophytes enhance the fitness of their host plants by direct production of bioactive secondary metabolites, which are involved in protecting the host against herbivores and pathogenic microbes. In addition, it is increasingly apparent that endophytes are able to biosynthesize medicinally important "phytochemicals", originally believed to be produced only by their host plants.
OBJECTIVE
The present review provides an overview of secondary metabolites from endophytic fungi with pronounced biological activities covering the literature between 2010 and 2017. Special focus is given on studies aiming at exploration of the mode of action of these metabolites towards the discovery of leads from endophytic fungi. Moreover, this review critically evaluates the potential of endophytic fungi as alternative sources of bioactive "plant metabolites".
RESULTS
Over the past few years, several promising lead structures from endophytic fungi have been described in the literature. In this review, 65 metabolites are outlined with pronounced biological activities, primarily as antimicrobial and cytotoxic agents. Some of these metabolites have shown to be highly selective or to possess novel mechanisms of action, which hold great promises as potential drug candidates.
CONCLUSION
Endophytes represent an inexhaustible reservoir of pharmacologically important compounds. Moreover, endophytic fungi could be exploited for the sustainable production of bioactive "plant metabolites" in the future. Towards this aim, further insights into the dynamic endophyte - host plant interactions and origin of endophytic fungal genes would be of utmost importance.
Topics: Anti-Infective Agents; Endophytes; Fungi; Phytochemicals; Plants
PubMed: 31526342
DOI: 10.2174/0929867326666190916144709 -
Research in Veterinary Science May 2021Amebiasis is a disease caused by the protozoan parasite Entamoeba histolytica, which mainly shows symptoms of acute diarrhea, dysentery, amebic colitis, and amebic liver... (Review)
Review
Amebiasis is a disease caused by the protozoan parasite Entamoeba histolytica, which mainly shows symptoms of acute diarrhea, dysentery, amebic colitis, and amebic liver abscesses. As the fourth leading parasitic cause of human mortality, E. histolytica mainly infect children in developing countries, transmitted by food and water contamination. In the majority of infected individuals, Entamoeba sp. asymptomatically colonizes the large intestine and self-limiting, while in others, the parasite breaches the mucosal epithelial barrier to cause amebic colitis and can disseminate to soft organs to cause abscesses. Metronidazole (MTZ) is the recommended and most widely used drug for treating the invasive amebiasis. No amebiasis vaccine has been approved for human clinical trials to date, but many recent vaccine development studies hold promise. For the prevention and control of amebiasis, improvement of water purification systems and hygiene practices could decrease disease incidence. In this review, we focus on the epidemiology, transmission, clinical signs, pathogenesis, diagnosis, treatment, prevention and control of the zoonotic amebiasis.
Topics: Amebiasis; Animals; Antiprotozoal Agents; Diarrhea; Dysentery, Amebic; Entamoeba histolytica; Humans; Metronidazole; Zoonoses
PubMed: 33676155
DOI: 10.1016/j.rvsc.2021.02.021 -
Anti-inflammatory & Anti-allergy Agents... 2023Cryptococcus neoformans and C. gattii pneumonitis could persist asymptomatically for indefinite periods, resolve, or progress to symptomatic dissemination, mainly in...
Cryptococcus neoformans and C. gattii pneumonitis could persist asymptomatically for indefinite periods, resolve, or progress to symptomatic dissemination, mainly in immunocompromised individuals (e.g., treated with corticosteroids). The symptoms of COVID-19 may range from a self-limiting illness with general symptoms, such as fever, to more severe complications, such as pneumonitis. The glucocorticoids emerged as potential for treatment of COVID-19, mainly those patients who required ventilator therapy. However, although treatment with glucocorticoids has shown benefits in patients with COVID-19, they can be dangerous due to increased risk of coinfections and superinfections caused by opportunistic pathogens such as Cryptococcus ssp. Some patients with severe COVID-19 pneumonia treated with glucocorticoids developed cryptococcal infection and died. Therefore, immunomodulatory therapy could increase the susceptibility to acute infection or reactivation of Cryptococcus ssp in COVID-19 patients, and this could be complicated once pulmonary cryptococcosis has symptoms similar to COVID-19 becomes difficult to distinguish between the two disease states and treatment.
Topics: Humans; Glucocorticoids; COVID-19; Cryptococcosis; Cryptococcus neoformans; Cryptococcus gattii
PubMed: 37702231
DOI: 10.2174/1871523022666230912142540 -
Dermatologic Clinics Oct 2021Children are a unique subset of patients in relation to the COVID-19 pandemic, often presenting asymptomatically, mildly, or atypically. Manifestations of the skin may... (Review)
Review
Children are a unique subset of patients in relation to the COVID-19 pandemic, often presenting asymptomatically, mildly, or atypically. Manifestations of the skin may be a primary (or the only) presenting sign. Recognizing cutaneous manifestations of COVID-19 in the pediatric population is important to guiding precautions, testing, and management for patients and close contacts. Whereas some dermatologic signs in children overlap with those in adults, other skin findings are reported with higher frequency in children and may be clues to multisystemic sequelae. This article describes presentation, pathophysiologic theories, and management strategies for cutaneous manifestations of COVID-19 in children.
Topics: COVID-19; COVID-19 Testing; Child; Humans; Skin Diseases, Viral; Systemic Inflammatory Response Syndrome
PubMed: 34556241
DOI: 10.1016/j.det.2021.05.012 -
Cell Host & Microbe Apr 2023Candida auris and Candida albicans can result in invasive fungal diseases. And yet, these species can stably and asymptomatically colonize human skin and... (Review)
Review
Candida auris and Candida albicans can result in invasive fungal diseases. And yet, these species can stably and asymptomatically colonize human skin and gastrointestinal tracts. To consider these disparate microbial lifestyles, we first review factors shown to influence the underlying microbiome. Structured by the damage response framework, we then consider the molecular mechanisms deployed by C. albicans to switch between commensal and pathogenic lifestyles. Next, we explore this framework with C. auris to highlight how host physiology, immunity, and/or antibiotic receipt are associated with progression from colonization to infection. While treatment with antibiotics increases the risk that an individual will succumb to invasive candidiasis, the underlying mechanisms remain unclear. Here, we describe several hypotheses that may explain this phenomenon. We conclude by highlighting future directions integrating genomics with immunology to advance our understanding of invasive candidiasis and human fungal disease.
Topics: Humans; Mycobiome; Symbiosis; Host-Pathogen Interactions; Candida albicans; Candidiasis, Invasive
PubMed: 37054674
DOI: 10.1016/j.chom.2023.02.010 -
Mathematical Biosciences and... Nov 2020Asymptomatic transmission of infectious diseases has been recognized recently in several epidemics or pandemics. There is a great need to incorporate asymptomatic...
Asymptomatic transmission of infectious diseases has been recognized recently in several epidemics or pandemics. There is a great need to incorporate asymptomatic transmissions into traditional modeling of infectious diseases and to study how asymptomatic transmissions shift epidemic dynamics. In this work, we propose a compartmental model with asymptomatic transmissions for waterborne infectious diseases. We conduct a detailed analysis and numerical study with shigellosis data. Two parameters, the proportion $p$ of asymptomatic infected individuals and the proportion $k$ of asymptomatic infectious individuals who can asymptomatically transmit diseases, play major rules in the epidemic dynamics. The basic reproduction number $\mathscr{R}_{0}$ is a decreasing function of parameter $p$ when parameter $k$ is smaller than a critical value while $\mathscr{R}_{0}$ is an increasing function of $p$ when $k$ is greater than the critical value. $\mathscr{R}_{0}$ is an increasing function of $k$ for any value of $p$. When $\mathscr{R}_{0}$ passes through 1 as $p$ or $k$ varies, the dynamics of epidemics is shifted. If asymptomatic transmissions are not counted, $\mathscr{R}_{0}$ will be underestimated while the final size may be overestimated or underestimated. Our study provides a theoretical example for investigating other asymptomatic transmissions and useful information for public health measurements in waterborne infectious diseases.
Topics: Asymptomatic Infections; Basic Reproduction Number; Communicable Diseases; Epidemics; Humans; Pandemics
PubMed: 33525082
DOI: 10.3934/mbe.2021005 -
PLoS Pathogens May 2023Streptococcus pneumoniae is an opportunistic pathogen that colonizes the upper respiratory tract asymptomatically and, upon invasion, can lead to severe diseases...
Streptococcus pneumoniae is an opportunistic pathogen that colonizes the upper respiratory tract asymptomatically and, upon invasion, can lead to severe diseases including otitis media, sinusitis, meningitis, bacteremia, and pneumonia. One of the first lines of defense against pneumococcal invasive disease is inflammation, including the recruitment of neutrophils to the site of infection. The invasive pneumococcus can be cleared through the action of serine proteases generated by neutrophils. It is less clear how serine proteases impact non-invasive pneumococcal colonization, which is the key first step to invasion and transmission. One significant aspect of pneumococcal biology and adaptation in the respiratory tract is its natural competence, which is triggered by a small peptide CSP. In this study, we investigate if serine proteases are capable of degrading CSP and the impact this has on pneumococcal competence. We found that CSP has several potential sites for trypsin-like serine protease degradation and that there were preferential cleavage sites recognized by the proteases. Digestion of CSP with two different trypsin-like serine proteases dramatically reduced competence in a dose-dependent manner. Incubation of CSP with mouse lung homogenate also reduced recombination frequency of the pneumococcus. These ex vivo experiments suggested that serine proteases in the lower respiratory tract reduce pneumococcal competence. This was subsequently confirmed measuring in vivo recombination frequencies after induction of protease production via poly (I:C) stimulation and via co-infection with influenza A virus, which dramatically lowered recombination events. These data shed light on a new mechanism by which the host can modulate pneumococcal behavior and genetic exchange via direct degradation of the competence signaling peptide.
Topics: Animals; Mice; Streptococcus pneumoniae; Pneumococcal Infections; Inflammation; Serine Proteases; Peptides
PubMed: 37256908
DOI: 10.1371/journal.ppat.1011421