Role of acute infection in HIV transmission

The coronavirus disease 2019 (COVID-19) pandemic has spread rapidly worldwide, with more than two million deaths. Evidence indicates the critical role of the vascular endothelium in its pathophysiology but, like potential changes in functional vasodilation, the vascular effect of SARS-CoV-2 at a given distance from the acute infection is largely unknown. We assessed brachial artery flow-mediated dilatation (FMD) in 27 COVID-19 patients needing conventional or intensive care unit hospitalization, three months after SARS-CoV-2 infection diagnosis and in nine age- and sex- matched control subjects. Interestingly, the FMD was lower in COVID-19 patients as compared to controls (8.2 (7.2–8.9) vs. 10.3 (9.1–11.7)); p = 0.002, and half of the hospitalized COVID-19 survivors presented with a reduced FMD < 8% at three months of COVID-19 onset. Impaired FMD was not associated with severe or critical SARS-CoV-2 infection, reflected by ICU hospitalization, total hospitalization duration, or severity of lung damage. In conclusion, reduced FMD is often observed even three months after hospitalization for SARS-CoV-2 infection, but such alteration predominantly appears to not be related to COVID-19 severity. Longer and larger follow-up studies will help to clarify the potential prognosis value of FMD among COVID-19 patients, as well as to further determine the mechanisms involved.

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Acute melioidosis outbreak in Western Australia

Epidemiology and Infection ◽

10.1017/s0950268899002964 ◽

1999 ◽

Vol 123 (3) ◽

pp. 437-443 ◽

Cited By ~ 47

Author(s):

T. J. J. INGLIS ◽

S. C. GARROW ◽

C. ADAMS ◽

M. HENDERSON ◽

M. MAYO ◽

...

Keyword(s):

Environmental Factors ◽

Water Supply ◽

Western Australia ◽

Burkholderia Pseudomallei ◽

Acute Infection ◽

Exposure Period ◽

Pfge Type ◽

Chromosomal Dna ◽

Potable Water Supply

A cluster of acute melioidosis cases occurred in a remote, coastal community in tropical Western Australia. Molecular typing of Burkholderia pseudomallei isolates from culture-confirmed cases and suspected environmental sources by pulsed-field gel electrophoresis (PFGE) of XbaI chromosomal DNA digests showed that a single PFGE type was responsible for five cases of acute infection in a community of around 300 during a 5 week period. This temporal and geographical clustering of acute melioidosis cases provided a unique opportunity to investigate the environmental factors contributing to this disease. B. pseudomallei isolated from a domestic tap at the home of an asymptomatic seroconverter was indistinguishable by PFGE. Possible contributing environmental factors included an unusually acid communal water supply, unrecordable chlorine levels during the probable exposure period, a nearby earth tremor, and gusting winds during the installation of new water and electricity supplies. The possible role of the potable water supply as a source of B. pseudomallei was investigated further.

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Prevention of HIV transmission in the UK: what is the role of male circumcision?

Sexually Transmitted Infections ◽

10.1136/sti.2008.029934 ◽

2008 ◽

Vol 84 (3) ◽

pp. 158-160 ◽

Cited By ~ 7

Author(s):

A. MacDonald ◽

J. Humphreys ◽

H. W Jaffe

Keyword(s):

Male Circumcision ◽

Hiv Transmission ◽

The Uk ◽

Prevention Of Hiv

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Navigating the Complexity of HIV/AIDS in African Peacekeeping Missions: Challenges and Prospects

Journal of International Peacekeeping ◽

10.1163/18754112-1704010 ◽

2013 ◽

Vol 17 (3-4) ◽

pp. 361-384

Author(s):

Ayodele Akenroye

Keyword(s):

Cold War ◽

Hiv Transmission ◽

Ethnic Conflicts ◽

Post Conflict ◽

Un Peacekeeping ◽

Un Security Council ◽

Peacekeeping Missions ◽

The Cold War ◽

Hiv Aids

The end of the Cold War witnessed the resurgence of ethnic conflicts in Africa, which necessitated the deployment of peacekeeping missions in many crisis contexts. The risk of HIV transmission increases in post-conflict environments where peacekeepers are at risk of contracting and spreading HIV/AIDS. In response, UN Security Council Resolution 1308 (2000) stressed the need for the UN to incorporate HIV/AIDS prevention awareness skills and advice in its training for peacekeepers. However, troops in peacekeeping missions remain under national command, thus limiting the UN prerogatives. This article discusses the risk of peacekeepers contracting or transmitting HIV/AIDS, as well as the role of peacekeeping missions in controlling the spread of the disease, and offers an account of the steps taken within UN peacekeeping missions and African regional peacekeeping initiatives to tackle the challenges of HIV/AIDS. While HIV/AIDS remains a scourge that could weaken peacekeeping in Africa, it seems that inertia has set in, making it even more difficult to tackle the complexity of this phenomenon.

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The Role of Interferons in Driving Susceptibility to Asthma Following Bronchiolitis: Controversies and Research Gaps

Frontiers in Immunology ◽

10.3389/fimmu.2021.761660 ◽

2021 ◽

Vol 12 ◽

Author(s):

Heidi Makrinioti ◽

Andrew Bush ◽

James Gern ◽

Sebastian Lennox Johnston ◽

Nikolaos Papadopoulos ◽

...

Keyword(s):

Immune Responses ◽

Acute Infection ◽

Respiratory Viruses ◽

Future Research ◽

Innate Immune Responses ◽

Asthmatic Children ◽

Recurrent Wheeze ◽

The Relationship

Bronchiolitis is the most common cause of hospitalization in infancy and is associated with a higher risk for the development of childhood asthma. However, not all children hospitalized with bronchiolitis will develop asthma. The mechanisms underlying asthma development following bronchiolitis hospitalization are complex. Immune responses to respiratory viruses may underlie both bronchiolitis severity and long-term sequela (such as asthma). Interferons (IFNs) are important components of innate immune responses to respiratory viruses and could influence both asthma development and asthma exacerbations. However, the nature of the relationship between interferon production and wheezing illnesses is controversial. For example, low peripheral blood IFN responses at birth have been linked with recurrent wheeze and asthma development. In contrast, there is evidence that severe illnesses (e.g., hospitalization for bronchiolitis) are associated with increased IFN responses during acute infection (bronchiolitis hospitalization) and a higher risk for subsequent asthma diagnosis. Furthermore, mechanistic studies suggest that bronchial epithelial cells from asthmatic children have impaired IFN responses to respiratory viruses, which may enable increased viral replication followed by exaggerated secondary IFN responses. This review aims to discuss controversies around the role of IFNs as drivers of susceptibility to asthma development following bronchiolitis hospitalization. Past evidence from both mechanistic and cohort studies are discussed. We will highlight knowledge gaps that can inform future research study design.

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Limited within-host diversity and tight transmission bottlenecks limit SARS-CoV-2 evolution in acutely infected individuals

10.1101/2021.04.30.440988 ◽

2021 ◽

Author(s):

Katarina Braun ◽

Gage Kahl Moreno ◽

Cassia Wagner ◽

Molly A. Accola ◽

William M Rehrauer ◽

...

Keyword(s):

Immune Escape ◽

Acute Infection ◽

Host Diversity ◽

Recent Emergence ◽

Novel Variants ◽

Efficient Selection

The recent emergence of divergent SARS-CoV-2 lineages has raised concerns about the role of selection within individual hosts in propagating novel variants. Of particular concern are variants associated with immune escape and/or enhanced transmissibility. Though growing evidence suggests that novel variants can arise during prolonged infections, most infections are acute. Understanding the extent to which variants emerge and transmit among acutely infected hosts is therefore critical for predicting the pace at which variants resistant to vaccines or conferring increased transmissibility might emerge in the majority of SARS-CoV-2 infections. To characterize how within-host diversity is generated and propagated, we combine extensive laboratory and bioinformatic controls with metrics of within- and between-host diversity to 133 SARS-CoV-2 genomes from acutely infected individuals. We find that within-host diversity during acute infection is low and transmission bottlenecks are narrow, with very few viruses founding most infections. Within-host variants are rarely transmitted, even among individuals within the same household. Accordingly, we also find that within-host variants are rarely detected along phylogenetically linked infections in the broader community. Together, these findings suggest that efficient selection and transmission of novel SARS-CoV-2 variants is unlikely during typical, acute infection.

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Severe Acute Infection Due to Serratia marcescens Causing Respiratory Distress in An Immunocompetent Adult

Romanian Journal of Internal Medicine ◽

10.1515/rjim-2016-0013 ◽

2016 ◽

Vol 54 (2) ◽

pp. 134-136 ◽

Cited By ~ 2

Author(s):

Pablo Ruiz-Sada ◽

Mikel Escalante ◽

Eva Lizarralde

Keyword(s):

Risk Factors ◽

Respiratory Distress ◽

Serratia Marcescens ◽

Distress Syndrome ◽

Acute Infection ◽

Human Pathogen ◽

Immunocompetent Adult ◽

Uncommon Presentation ◽

Opportunistic Human Pathogen

AbstractThe role ofSerratia marcescenschanged from a harmless saprophytic microorganism to an important opportunistic human pathogen. It often causes nosocomial device-associated outbreaks and rarely serious invasive community acquired infections. We present a case of a community-acquiredSerratia marcescensbacteremia leading to Respiratory Distress Syndrome in a previously healthy 51-year-old man without identifiable risk factors. Full recovery was achieved with solely medical treatment and observation in ICU during three days. To our knowledge it is an extremely uncommon presentation and just few cases have been previously reported in the literature.

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Role of Endothelin 1 in the Pathogenesis of Chronic Chagasic Heart Disease

Infection and Immunity ◽

10.1128/iai.73.4.2496-2503.2005 ◽

2005 ◽

Vol 73 (4) ◽

pp. 2496-2503 ◽

Cited By ~ 64

Author(s):

Herbert B. Tanowitz ◽

Huan Huang ◽

Linda A. Jelicks ◽

Madhulika Chandra ◽

Maria L. Loredo ◽

...

Keyword(s):

Cardiac Myocyte ◽

Acute Infection ◽

Left Ventricular ◽

Internal Diameter ◽

Resonance Imaging ◽

Endothelin 1 ◽

Chagasic Cardiomyopathy ◽

Brazil Strain ◽

Fractional Shortening

ABSTRACT On the basis of previous observations, endothelin 1 (ET-1) has been suggested as contributing to the pathogenesis of Chagasic cardiomyopathy. Therefore, ET-1flox/flox;α-MHC-Cre(+) mice in which the ET-1 gene was deleted from cardiac myocytes and ET-1flox/flox;Tie 2 Cre(+) mice in which the ET-1 gene was deleted from endothelial cells were infected with Trypanosoma cruzi. Genetic controls for these cell-specific ET-1 knockout mice were used. Ninety percentage of all mice survived acute infection with the Brazil strain and were evaluated 130 days postinfection. Inflammation and fibrosis were observed in all infected mice; however, fibrosis was reduced in ET-1flox/flox;α-MHC-Cre(+) mice. Cardiac magnetic resonance imaging revealed that infection resulted in a significant increase in right ventricular internal diameter (RVID) in all mice except ET-1flox/flox;α-MHC-Cre(+) mice; i.e., RVID was not changed in infected ET-1flox/flox;α-MHC-Cre(+) mice. Echocardiography of the left ventricle demonstrated increased left ventricular end-diastolic diameter, reduced fractional shortening, and decreased relative wall thickness in infected mice. However, the magnitude of the changes was significantly less in ET-1flox/flox;α-MHC-Cre(+) mice compared to other groups. These data provide further evidence of a role for ET-1, particularly cardiac myocyte-derived ET-1, in the pathogenesis of chronic Chagasic cardiomyopathy.

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