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AIDS (London, England) Jun 2014Effective HIV prevention programs rely on accurate estimates of the per-act risk of HIV acquisition from sexual and parenteral exposures. We updated the previous risk... (Review)
Review
BACKGROUND
Effective HIV prevention programs rely on accurate estimates of the per-act risk of HIV acquisition from sexual and parenteral exposures. We updated the previous risk estimates of HIV acquisition from parenteral, vertical, and sexual exposures, and assessed the modifying effects of factors including condom use, male circumcision, and antiretroviral therapy.
METHODS
We conducted literature searches to identify new studies reporting data regarding per-act HIV transmission risk and modifying factors. Of the 7339 abstracts potentially related to per-act HIV transmission risk, three meta-analyses provided pooled per-act transmission risk probabilities and two studies provided data on modifying factors. Of the 8119 abstracts related to modifying factors, 15 relevant articles, including three meta-analyses, were included. We used fixed-effects inverse-variance models on the logarithmic scale to obtain updated estimates of certain transmission risks using data from primary studies, and employed Poisson regression to calculate relative risks with exact 95% confidence intervals for certain modifying factors.
RESULTS
Risk of HIV transmission was greatest for blood transfusion, followed by vertical exposure, sexual exposures, and other parenteral exposures. Sexual exposure risks ranged from low for oral sex to 138 infections per 10,000 exposures for receptive anal intercourse. Estimated risks of HIV acquisition from sexual exposure were attenuated by 99.2% with the dual use of condoms and antiretroviral treatment of the HIV-infected partner.
CONCLUSION
The risk of HIV acquisition varied widely, and the estimates for receptive anal intercourse increased compared with previous estimates. The risk associated with sexual intercourse was reduced most substantially by the combined use of condoms and antiretroviral treatment of HIV-infected partners.
Topics: Disease Transmission, Infectious; HIV Infections; Humans; Iatrogenic Disease; Infectious Disease Transmission, Vertical; Mother-Child Relations; Risk Assessment; Sexual Behavior
PubMed: 24809629
DOI: 10.1097/QAD.0000000000000298 -
PLoS Neglected Tropical Diseases Apr 2020Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) and the more recently discovered Mycobacterium lepromatosis (M. lepromatosis). The two...
Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae) and the more recently discovered Mycobacterium lepromatosis (M. lepromatosis). The two leprosy bacilli cause similar pathologic conditions. They primarily target the skin and the peripheral nervous system. Currently it is considered a Neglected Tropical Disease, being endemic in specific locations within countries of the Americas, Asia, and Africa, while in Europe it is only rarely reported. The reason for a spatial inequality in the prevalence of leprosy in so-called endemic pockets within a country is still largely unexplained. A systematic review was conducted targeting leprosy transmission research data, using PubMed and Scopus as sources. Publications between January 1, 1945 and July 1, 2019 were included. The transmission pathways of M. leprae are not fully understood. Solid evidence exists of an increased risk for individuals living in close contact with leprosy patients, most likely through infectious aerosols, created by coughing and sneezing, but possibly also through direct contact. However, this systematic review underscores that human-to-human transmission is not the only way leprosy can be acquired. The transmission of this disease is probably much more complicated than was thought before. In the Americas, the nine-banded armadillo (Dasypus novemcinctus) has been established as another natural host and reservoir of M. leprae. Anthroponotic and zoonotic transmission have both been proposed as modes of contracting the disease, based on data showing identical M. leprae strains shared between humans and armadillos. More recently, in red squirrels (Sciurus vulgaris) with leprosy-like lesions in the British Isles M. leprae and M. lepromatosis DNA was detected. This finding was unexpected, because leprosy is considered a disease of humans (with the exception of the armadillo), and because it was thought that leprosy (and M. leprae) had disappeared from the United Kingdom. Furthermore, animals can be affected by other leprosy-like diseases, caused by pathogens phylogenetically closely related to M. leprae. These mycobacteria have been proposed to be grouped as a M. leprae-complex. We argue that insights from the transmission and reservoirs of members of the M. leprae-complex might be relevant for leprosy research. A better understanding of possible animal or environmental reservoirs is needed, because transmission from such reservoirs may partly explain the steady global incidence of leprosy despite effective and widespread multidrug therapy. A reduction in transmission cannot be expected to be accomplished by actions or interventions from the human healthcare domain alone, as the mechanisms involved are complex. Therefore, to increase our understanding of the intricate picture of leprosy transmission, we propose a One Health transdisciplinary research approach.
Topics: Animals; Armadillos; Disease Reservoirs; Disease Transmission, Infectious; Global Health; Humans; Incidence; Leprosy; Mycobacterium; Mycobacterium leprae; Prevalence; Sciuridae
PubMed: 32339201
DOI: 10.1371/journal.pntd.0008276 -
Lancet (London, England) Jun 2020Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 and is spread person-to-person through close contact. We aimed to investigate the effects of... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 and is spread person-to-person through close contact. We aimed to investigate the effects of physical distance, face masks, and eye protection on virus transmission in health-care and non-health-care (eg, community) settings.
METHODS
We did a systematic review and meta-analysis to investigate the optimum distance for avoiding person-to-person virus transmission and to assess the use of face masks and eye protection to prevent transmission of viruses. We obtained data for SARS-CoV-2 and the betacoronaviruses that cause severe acute respiratory syndrome, and Middle East respiratory syndrome from 21 standard WHO-specific and COVID-19-specific sources. We searched these data sources from database inception to May 3, 2020, with no restriction by language, for comparative studies and for contextual factors of acceptability, feasibility, resource use, and equity. We screened records, extracted data, and assessed risk of bias in duplicate. We did frequentist and Bayesian meta-analyses and random-effects meta-regressions. We rated the certainty of evidence according to Cochrane methods and the GRADE approach. This study is registered with PROSPERO, CRD42020177047.
FINDINGS
Our search identified 172 observational studies across 16 countries and six continents, with no randomised controlled trials and 44 relevant comparative studies in health-care and non-health-care settings (n=25 697 patients). Transmission of viruses was lower with physical distancing of 1 m or more, compared with a distance of less than 1 m (n=10 736, pooled adjusted odds ratio [aOR] 0·18, 95% CI 0·09 to 0·38; risk difference [RD] -10·2%, 95% CI -11·5 to -7·5; moderate certainty); protection was increased as distance was lengthened (change in relative risk [RR] 2·02 per m; p=0·041; moderate certainty). Face mask use could result in a large reduction in risk of infection (n=2647; aOR 0·15, 95% CI 0·07 to 0·34, RD -14·3%, -15·9 to -10·7; low certainty), with stronger associations with N95 or similar respirators compared with disposable surgical masks or similar (eg, reusable 12-16-layer cotton masks; p=0·090; posterior probability >95%, low certainty). Eye protection also was associated with less infection (n=3713; aOR 0·22, 95% CI 0·12 to 0·39, RD -10·6%, 95% CI -12·5 to -7·7; low certainty). Unadjusted studies and subgroup and sensitivity analyses showed similar findings.
INTERPRETATION
The findings of this systematic review and meta-analysis support physical distancing of 1 m or more and provide quantitative estimates for models and contact tracing to inform policy. Optimum use of face masks, respirators, and eye protection in public and health-care settings should be informed by these findings and contextual factors. Robust randomised trials are needed to better inform the evidence for these interventions, but this systematic appraisal of currently best available evidence might inform interim guidance.
FUNDING
World Health Organization.
Topics: Betacoronavirus; COVID-19; Communicable Disease Control; Coronavirus Infections; Eye Protective Devices; Humans; Masks; Pandemics; Physical Distancing; Pneumonia, Viral; SARS-CoV-2; Social Isolation
PubMed: 32497510
DOI: 10.1016/S0140-6736(20)31142-9 -
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 -
Antimicrobial Resistance and Infection... Jun 2021Knowledge of infection prevention and control (IPC) procedures among healthcare workers (HCWs) is crucial for effective IPC. Compliance with IPC measures has critical... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Knowledge of infection prevention and control (IPC) procedures among healthcare workers (HCWs) is crucial for effective IPC. Compliance with IPC measures has critical implications for HCWs safety, patient protection and the care environment.
AIMS
To discuss the body of available literature regarding HCWs' knowledge of IPC and highlight potential factors that may influence compliance to IPC precautions.
DESIGN
A systematic review. A protocol was developed based on the Preferred Reporting Items for Systematic reviews and Meta-Analysis [PRISMA] statement.
DATA SOURCES
Electronic databases (PubMed, CINAHL, Embase, Proquest, Wiley online library, Medline, and Nature) were searched from 1 January 2006 to 31 January 2021 in the English language using the following keywords alone or in combination: knowledge, awareness, healthcare workers, infection, compliance, comply, control, prevention, factors. 3417 papers were identified and 30 papers were included in the review.
RESULTS
Overall, the level of HCW knowledge of IPC appears to be adequate, good, and/or high concerning standard precautions, hand hygiene, and care pertaining to urinary catheters. Acceptable levels of knowledge were also detected in regards to IPC measures for specific diseases including TB, MRSA, MERS-CoV, COVID-19 and Ebola. However, gaps were identified in several HCWs' knowledge concerning occupational vaccinations, the modes of transmission of infectious diseases, and the risk of infection from needle stick and sharps injuries. Several factors for noncompliance surrounding IPC guidelines are discussed, as are recommendations for improving adherence to those guidelines.
CONCLUSION
Embracing a multifaceted approach towards improving IPC-intervention strategies is highly suggested. The goal being to improve compliance among HCWs with IPC measures is necessary.
Topics: COVID-19; Cross Infection; Databases, Factual; Guideline Adherence; Health Knowledge, Attitudes, Practice; Health Personnel; Humans; Infection Control; Infectious Disease Transmission, Patient-to-Professional; SARS-CoV-2
PubMed: 34082822
DOI: 10.1186/s13756-021-00957-0 -
Infection Apr 2021The coronavirus outbreak emerged as a severe pandemic, claiming more than 0.8 million lives across the world and raised a major global health concern. We survey the...
PURPOSE
The coronavirus outbreak emerged as a severe pandemic, claiming more than 0.8 million lives across the world and raised a major global health concern. We survey the history and mechanism of coronaviruses, and the structural characteristics of the spike protein and its key residues responsible for human transmissions.
METHODS
We have carried out a systematic review to summarize the origin, transmission and etiology of COVID-19. The structural analysis of the spike protein and its disordered residues explains the mechanism of the viral transmission. A meta-data analysis of the therapeutic compounds targeting the SARS-CoV-2 is also included.
RESULTS
Coronaviruses can cross the species barrier and infect humans with unexpected consequences for public health. The transmission rate of SARS-CoV-2 infection is higher compared to that of the closely related SARS-CoV infections. In SARS-CoV-2 infection, intrinsically disordered regions are observed at the interface of the spike protein and ACE2 receptor, providing a shape complementarity to the complex. The key residues of the spike protein have stronger binding affinity with ACE2. These can be probable reasons for the higher transmission rate of SARS-CoV-2. In addition, we have also discussed the therapeutic compounds and the vaccines to target SARS-CoV-2, which can help researchers to develop effective drugs/vaccines for COVID-19. The overall history and mechanism of entry of SARS-CoV-2 along with structural study of spike-ACE2 complex provide insights to understand disease pathogenesis and development of vaccines and drugs.
Topics: Amino Acid Sequence; Animals; COVID-19; Coronavirus Infections; Humans; Protein Binding; Protein Folding; SARS-CoV-2; Spike Glycoprotein, Coronavirus; Virus Internalization; COVID-19 Drug Treatment
PubMed: 32886331
DOI: 10.1007/s15010-020-01516-2 -
European Journal of Medical Research Jan 2021Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), belonging to the Coronaviridae family, is agent of 2019 novel coronavirus disease (COVID-19). COVID-19... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND AIMS
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), belonging to the Coronaviridae family, is agent of 2019 novel coronavirus disease (COVID-19). COVID-19 emerged in Wuhan, Hubei province of China, in early December 2019 and is now considered a pandemic. This study aimed to investigate the airborne transmission of COVID-19 and the role of face mask to prevent it.
METHODS
A systematic search for English-language literature was done via PUBMED/Medline and Google Scholar up to October 2020. There was two search strategy; for airborne transmission and the role of face mask for prevention of SARS-CoV-2 infection. Based on a fixed and random effects model, the RR and 95% CI were used to evaluate the combined risk. This meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) Guidelines.
RESULTS
After eligibility assessment, four articles with a total of 7688 participants were included in this meta-analysis. The result of this meta-analysis has shown significant reduction in infection with face mask use; the pooled RR (95%CI) was 0.12 [0.06, 0.27] (P < 0.001).
CONCLUSION
In conclusion, this meta-analysis suggests that there is association between face mask use and reduction of COVID-19. However, COVID-19 spreads primarily with contact routes and respiratory droplets, but its transmissibility has many mysteries yet and there is controversy about airborne transmission of COVID-19.
Topics: COVID-19; Humans; Masks; SARS-CoV-2
PubMed: 33388089
DOI: 10.1186/s40001-020-00475-6 -
Frontiers in Immunology 2021Breastfeeding not only provides the optimum source of nutrients for the neonate and its first strong shield against infection but also lays the foundation for somatic... (Meta-Analysis)
Meta-Analysis
Breastfeeding not only provides the optimum source of nutrients for the neonate and its first strong shield against infection but also lays the foundation for somatic and psychological bonding between the mother and child. During the current COVID-19 pandemic, although the guidelines of the relevant international and national agencies recommend breastfeeding by SARS-CoV-2-infected mothers, considerable insecurity persists in daily clinical practice regarding the safety of the infants and the perceived advantages and disadvantages of discontinuation of breastfeeding. This is a systematic review of the currently available information regarding the transmissibility of SARS-CoV-2 through or while breastfeeding and the protection against infection that breast milk might provide. The accumulated body of knowledge regarding the role of breast milk in the development of the neonatal immune system and protection against infection by other respiratory viruses is discussed, with a focus on the anti-inflammatory role of the antibodies, microbes, and viruses provided to the infant in breast milk and its relevance to the case of SARS-CoV-2.
Topics: Antibodies, Viral; Breast Feeding; COVID-19; Female; Humans; Infant, Newborn; Infectious Disease Transmission, Vertical; Milk, Human; Pregnancy; Pregnancy Complications, Infectious; SARS-CoV-2
PubMed: 33897707
DOI: 10.3389/fimmu.2021.661806 -
Clinical Microbiology and Infection :... Jan 2014Healthcare-associated infections due to multidrug-resistant Gram-negative bacteria (MDR-GNB) are a leading cause of morbidity and mortality worldwide. These... (Review)
Review
Healthcare-associated infections due to multidrug-resistant Gram-negative bacteria (MDR-GNB) are a leading cause of morbidity and mortality worldwide. These evidence-based guidelines have been produced after a systematic review of published studies on infection prevention and control interventions aimed at reducing the transmission of MDR-GNB. The recommendations are stratified by type of infection prevention and control intervention and species of MDR-GNB and are presented in the form of 'basic' practices, recommended for all acute care facilities, and 'additional special approaches' to be considered when there is still clinical and/or epidemiological and/or molecular evidence of ongoing transmission, despite the application of the basic measures. The level of evidence for and strength of each recommendation, were defined according to the GRADE approach.
Topics: Anti-Infective Agents, Local; Bacterial Typing Techniques; Chlorhexidine; Cross Infection; Disease Outbreaks; Drug Resistance, Multiple, Bacterial; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Hand Hygiene; Health Knowledge, Attitudes, Practice; Humans; Infection Control; Risk Factors
PubMed: 24329732
DOI: 10.1111/1469-0691.12427 -
Revista Brasileira de Enfermagem 2021Analyze available evidence related to SARS-CoV-2 infection and vertical transmission. (Review)
Review
OBJECTIVE
Analyze available evidence related to SARS-CoV-2 infection and vertical transmission.
METHODS
Scoping review, according to the Joanna Briggs Institute and PRISMA-ScR. Searches were conducted in five electronic databases to find publications about coronavirus infection and vertical transmission. Data were extracted, analyzed and synthesized by three independent researchers using a descriptive approach.
RESULTS
The search resulted in 76 publications. After selective steps, 15 articles - retrospective descriptive or case studies - were analyzed, all in English. In order to track the infection, specimens were collected from neonates through nasal swabs and C-reactive protein from breast milk, cord blood, amniotic fluid, placenta and vaginal secretion was analyzed. A small percentage of neonates tested positive for COVID-19, but these cases were not attributed to vertical transmission.
CONCLUSION
Vertical transmission could not be demonstrated. Research protocol registered with the Open Science Framework (https://osf.io/fawmv).
Topics: C-Reactive Protein; COVID-19; DNA, Viral; Female; Humans; Infant, Newborn; Infectious Disease Transmission, Vertical; Pandemics; Pregnancy; Pregnancy Complications, Infectious; Real-Time Polymerase Chain Reaction; SARS-CoV-2
PubMed: 34037165
DOI: 10.1590/0034-7167-2020-0849