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World Journal of Otorhinolaryngology -... Jan 2021Otolaryngologists are at increased occupational risk of Coronavirus Disease 2019 (COVID-19) infection due to exposure from respiratory droplets and aerosols generated... (Review)
Review
OBJECTIVE
Otolaryngologists are at increased occupational risk of Coronavirus Disease 2019 (COVID-19) infection due to exposure from respiratory droplets and aerosols generated during otologic, nasal, and oropharyngeal examinations and procedures. There have been a variety of guidelines and precautions developed to help mitigate this risk. While many reviews have focused on the personal protective equipment (PPE) and preparation guidelines for surgery in the COVID-19 era, none have focused on the more creative and unusual solutions designed to limit viral transmission. This review aims to fill that need.
DATA SOURCES
PubMed, Ovid/Medline, and Scopus.
METHODS
A comprehensive review of literature was performed on September 28, 2020 using PubMed, Ovid/Medline, and Scopus databases. All English-language studies were included if they proposed or assessed novel interventions developed for Otolaryngology practice during the COVID-19 pandemic. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed.
RESULTS
A total of 41 papers met inclusion criteria and were organized into 5 categories ('General Recommendations for Otolaryngologic Surgery', 'Equipment Shortage Solutions', 'Airway Procedures', 'Nasal Endoscopy and Skull Base Procedures', and 'Otologic Procedures'). Articles were summarized, highlighting the innovations created and evaluated during the COVID-19 pandemic. Creative solutions such as application of topical viricidal agents, make-shift mask filters, three-dimensional (3-D) printable adapters for headlights, aerosol containing separation boxes, and a variety of new draping techniques have been developed to limit the risk of COVID-19 transmission.
CONCLUSIONS
Persistent risk of COVID-19 exposure remains high. Thus, there is an increased need for solutions that mitigate the risk of viral transmission during office procedures and surgeries, especially given that most COVID-19 positive patients present asymptomatically. This review examines and organizes creative solutions that have been proposed and utilized in the otolaryngology. These solutions have a potential to minimize the risk of viral transmission in the current clinical environment and to create safer outpatient and operating room conditions for patients and healthcare staff.
PubMed: 33520334
DOI: 10.1016/j.wjorl.2021.01.001 -
Malaria Journal Jan 2021Plasmodium falciparum causes the majority of malaria cases worldwide and children in sub-Saharan Africa are the most vulnerable group affected. Non-sterile clinical...
BACKGROUND
Plasmodium falciparum causes the majority of malaria cases worldwide and children in sub-Saharan Africa are the most vulnerable group affected. Non-sterile clinical immunity that protects from symptoms develops slowly and is relatively short-lived. Moreover, current malaria vaccine candidates fail to induce durable high-level protection in endemic settings, possibly due to the immunomodulatory effects of the malaria parasite itself. Because dendritic cells play a crucial role in initiating immune responses, the aim of this study was to better understand the impact of cumulative malaria exposure as well as concurrent P. falciparum infection on dendritic cell phenotype and function.
METHODS
In this cross-sectional study, the phenotype and function of dendritic cells freshly isolated from peripheral blood samples of Malian adults with a lifelong history of malaria exposure who were either uninfected (n = 27) or asymptomatically infected with P. falciparum (n = 8) was assessed. Additionally, plasma cytokine and chemokine levels were measured in these adults and in Malian children (n = 19) with acute symptomatic malaria.
RESULTS
With the exception of lower plasmacytoid dendritic cell frequencies in asymptomatically infected Malian adults, peripheral blood dendritic cell subset frequencies and HLA-DR surface expression did not differ by infection status. Peripheral blood myeloid dendritic cells of uninfected Malian adults responded to in vitro stimulation with P. falciparum blood-stage parasites by up-regulating the costimulatory molecules HLA-DR, CD80, CD86 and CD40 and secreting IL-10, CXCL9 and CXCL10. In contrast, myeloid dendritic cells of asymptomatically infected Malian adults exhibited no significant responses above the uninfected red blood cell control. IL-10 and CXCL9 plasma levels were elevated in both asymptomatic adults and children with acute malaria.
CONCLUSIONS
The findings of this study indicate that myeloid dendritic cells of uninfected adults with a lifelong history of malaria exposure are able to up-regulate co-stimulatory molecules and produce cytokines. Whether mDCs of malaria-exposed individuals are efficient antigen-presenting cells capable of mounting an appropriate immune response remains to be determined. The data also highlights IL-10 and CXCL9 as important factors in both asymptomatic and acute malaria and add to the understanding of asymptomatic P. falciparum infections in malaria-endemic areas.
Topics: Adult; Asymptomatic Infections; Chemokines; Child; Child, Preschool; Cross-Sectional Studies; Cytokines; Dendritic Cells; Erythrocytes; Female; Humans; Malaria; Malaria, Falciparum; Male; Mali; Middle Aged; Phenotype; Plasmodium falciparum
PubMed: 33407502
DOI: 10.1186/s12936-020-03533-w -
International Journal of Infectious... Dec 2020Dengue infection is a global health threat. While symptomatic cases contribute to morbidity and mortality, the majority of infected people are asymptomatic but serve as...
BACKGROUND
Dengue infection is a global health threat. While symptomatic cases contribute to morbidity and mortality, the majority of infected people are asymptomatic but serve as an important reservoir. However, the kinetics of viremia in asymptomatic infections remains unknown.
METHODS
We enrolled 279 hospital-based symptomatic index cases and quantified dengue virus (DENV) RNA at enrollment and at the day of defervescence. To identify asymptomatic cases, 175 household members of index cases were monitored for clinical symptoms during follow-up, and blood was taken twice weekly to test for and quantify DENV RNA until cleared.
RESULTS
We detected DENV in thirteen asymptomatic household members (7.43%). Their DENV serotypes were primarily the same as those of their family index cases. The median peak DENV viremia in asymptomatic subjects was lower than that of symptomatic individuals during the febrile phase, and the viral decay rate was slower in asymptomatic infections.
CONCLUSIONS
DENV level and kinetics in asymptomatic individuals differed significantly from those of symptomatic cases. Despite the lower viremia, the slower decay rate in asymptomatic infections could lead to their prolonging the infectious reservoir. The improvement of transmission control to prevent such long-lived asymptomatic infections from transmitting the DENV is needed.
Topics: Adolescent; Adult; Child; Dengue; Dengue Virus; Female; Humans; Kinetics; Male; Serogroup; Viremia; Young Adult
PubMed: 32992011
DOI: 10.1016/j.ijid.2020.09.1446 -
Microorganisms Mar 2023and human papillomavirus (HPV) are the most common pathogens found in sexually transmitted infections (STIs), and both are known to increase the risk of cervical cancer... (Review)
Review
and human papillomavirus (HPV) are the most common pathogens found in sexually transmitted infections (STIs), and both are known to increase the risk of cervical cancer (CC) and infertility. HPV is extremely common worldwide, and scientists use it to distinguish between low-risk and high-risk genotypes. In addition, HPV transmission can occur via simple contact in the genital area. From 50 to 80% of sexually active individuals become infected with both and HPV viruses during their lifetime, and up to 50% become infected with an HPV oncogenic genotype. The natural history of this coinfection is strongly conditioned by the balance between the host microbiome and immune condition and the infecting agent. Though the infection often regresses, it tends to persist throughout adult life asymptomatically and silently. The partnership between HPV and is basically due to their similarities: common transmission routes, reciprocal advantages, and the same risk factors. is a Gram-negative bacteria, similar to HPV, and an intracellular bacterium, which shows a unique biphasic development that helps the latter continue its steady progression into the host throughout the entire life. Indeed, depending on the individual's immune condition, the infection tends to migrate toward the upper genital tract and spread to the uterus, and the fallopian tubes open up a pathway to HPV invasion. In addition, most HPV and infections related to the female genital tract are facilitated by the decay of the first line of defense in the vaginal environment, which is constituted by a healthy vaginal microbiome that is characterized by a net equilibrium of all its components. Thus, the aim of this paper was to highlight the complexity and fragility of the vaginal microenvironment and accentuate the fundamental role of all elements and systems involved, including the strains () and the immune-endocrine system, in preserving it from oncogenic mutation. Therefore, age, diet, and genetic predisposition together with an unspecific, persistent low-grade inflammatory state were found to be implicated in a high frequency and severity grade of disease, potentially resulting in pre-cancerous and cancerous cervical lesions.
PubMed: 36985236
DOI: 10.3390/microorganisms11030662 -
Frontiers in Cellular and Infection... 2022and are two obligate human pathogens that have evolved to be uniquely adapted to their host. The meningococcus is frequently carried asymptomatically in the... (Review)
Review
and are two obligate human pathogens that have evolved to be uniquely adapted to their host. The meningococcus is frequently carried asymptomatically in the nasopharynx, while gonococcal infection of the urogenital tract usually elicits a marked local inflammatory response. Other members of the genus are abundant in the upper airway where they could engage in co-operative or competitive interactions with both these pathogens. Here, we briefly outline the potential sites of contact between spp. in the body, with emphasis on the upper airway, and describe the growing yet circumstantial evidence for antagonism from carriage studies and human volunteer challenge models with . Recent laboratory studies have characterized antagonistic mechanisms that enable competition between species. Several of these mechanisms, including Multiple Adhesin family (Mafs), Two Partner Secretion Systems, and Type VI secretion system, involve direct contact between bacteria; the genetic organisation of these systems, and the domain structure of their effector molecules have striking similarities. Additionally, DNA from one species of can be toxic to another species, following uptake. More research is needed to define the full repertoire of antagonistic mechanisms in spp., their distribution in strains, their range of activity, and contribution to survival . Understanding the targets of effectors could reveal how antagonistic relationships between close relatives shape subsequent interactions between pathogens and their hosts.
Topics: Conflict of Interest; Humans; Nasopharynx; Neisseria; Neisseria gonorrhoeae; Neisseria meningitidis
PubMed: 35811666
DOI: 10.3389/fcimb.2022.913292 -
Risk Analysis : An Official Publication... Apr 2023Asymptomatic transmission complicates any public health strategies to combat a pandemic, which proved especially accurate in the case of COVID-19. Although asymptomatic...
Asymptomatic transmission complicates any public health strategies to combat a pandemic, which proved especially accurate in the case of COVID-19. Although asymptomatic cases are not unique to COVID-19, the high asymptomatic case rate raised many problems for developing effective public health interventions. The current modeling effort explored how asymptomatic transmission might impact pandemic responses in four key areas: isolation procedures, changes in reproduction rate, the potential for reduced transmission from asymptomatic cases, and social adherence to public health measures. A high rate of asymptomatic cases effectively requires large-scale public health suppression and mitigation procedures given that quarantine procedures alone could not prevent an outbreak for a virus such as SARS-CoV-2. This problem only becomes worse without lowering the effective reproduction rate, and even assuming the potential for reduced transmission, any virus with a high degree of asymptomatic transmission will likely produce a pandemic. Finally, there is a concern that asymptomatic individuals will also refuse to adhere to public health guidance. Analyses indicate that, given certain assumptions, even half of the population adhering to public health guidance could reduce the peak and flatten the curve by over 90%. Taken together, these analyses highlight the importance of taking asymptomatic cases into account when modeling viral spread and developing public health intervention strategies.
Topics: Humans; Pandemics; COVID-19; SARS-CoV-2; Public Health; Disease Outbreaks
PubMed: 33938019
DOI: 10.1111/risa.13736 -
International Journal of Infectious... Apr 2021The performance of the Roche Elecsys® Anti-SARS-CoV-2, Abbott Architect SARS-CoV-2 IgM, Abbott Architect SARS-CoV-2 IgG, Euroimmun SARS-CoV-2 IgA, Euroimmun SARS-CoV-2...
BACKGROUND
The performance of the Roche Elecsys® Anti-SARS-CoV-2, Abbott Architect SARS-CoV-2 IgM, Abbott Architect SARS-CoV-2 IgG, Euroimmun SARS-CoV-2 IgA, Euroimmun SARS-CoV-2 IgG ELISA, and Trillium IgG/IgM rapid assays was evaluated in Jamaica.
METHODS
Diagnostic sensitivities of the assays were assessed by testing serum samples from SARS-CoV-2 PCR-confirmed persons and diagnostic specificity was assessed by testing serum samples collected during 2018-2019 from healthy persons and from persons with antibodies to a wide range of viral infections.
RESULTS
Serum samples collected ≥14 days after onset of symptoms, or an initial SARS-CoV-2 RT-PCR positive test for asymptomatics, showed diagnostic sensitivities ranging from 67.9 to 75.0% when including all possible disease severities and increased to 90.0-95.0% when examining those with moderate to critical disease. Grouping moderate to critical disease showed a significant association with a SARS-CoV-2 antibody positive result for all assays. Diagnostic specificity ranged from 96.7 to 100.0%. For all assays examined, SARS-CoV-2 real-time PCR cycle threshold (Ct) values of the initial nasopharyngeal swab sample testing positive were significantly different for samples testing antibody positive versus negative.
CONCLUSIONS
These data from a predominantly African descent Caribbean population show comparable diagnostic sensitivities and specificities for all testing platforms assessed and limited utility of these tests for persons with asymptomatic and mild infections.
Topics: Antibodies, Viral; COVID-19; COVID-19 Serological Testing; Caribbean Region; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Jamaica; SARS-CoV-2; Sensitivity and Specificity
PubMed: 33610776
DOI: 10.1016/j.ijid.2021.02.059 -
Allergy Feb 2021The missing asymptomatic COVID-19 infections have been overlooked because of the imperfect sensitivity of the nucleic acid testing (NAT). Globally understanding the...
BACKGROUND
The missing asymptomatic COVID-19 infections have been overlooked because of the imperfect sensitivity of the nucleic acid testing (NAT). Globally understanding the humoral immunity in asymptomatic carriers will provide scientific knowledge for developing serological tests, improving early identification, and implementing more rational control strategies against the pandemic.
MEASURE
Utilizing both NAT and commercial kits for serum IgM and IgG antibodies, we extensively screened 11 766 epidemiologically suspected individuals on enrollment and 63 asymptomatic individuals were detected and recruited. Sixty-three healthy individuals and 51 mild patients without any preexisting conditions were set as controls. Serum IgM and IgG profiles were further probed using a SARS-CoV-2 proteome microarray, and neutralizing antibody was detected by a pseudotyped virus neutralization assay system. The dynamics of antibodies were analyzed with exposure time or symptoms onset.
RESULTS
A combination test of NAT and serological testing for IgM antibody discovered 55.5% of the total of 63 asymptomatic infections, which significantly raises the detection sensitivity when compared with the NAT alone (19%). Serum proteome microarray analysis demonstrated that asymptomatics mainly produced IgM and IgG antibodies against S1 and N proteins out of 20 proteins of SARS-CoV-2. Different from strong and persistent N-specific antibodies, S1-specific IgM responses, which evolved in asymptomatic individuals as early as the seventh day after exposure, peaked on days from 17 days to 25 days, and then disappeared in two months, might be used as an early diagnostic biomarker. 11.8% (6/51) mild patients and 38.1% (24/63) asymptomatic individuals did not produce neutralizing antibody. In particular, neutralizing antibody in asymptomatics gradually vanished in two months.
CONCLUSION
Our findings might have important implications for the definition of asymptomatic COVID-19 infections, diagnosis, serological survey, public health, and immunization strategies.
Topics: Adult; Aged; Antibodies, Neutralizing; Antibodies, Viral; COVID-19; COVID-19 Testing; Carrier State; Female; Humans; Immunoglobulin G; Immunoglobulin M; Male; Middle Aged; SARS-CoV-2
PubMed: 33040337
DOI: 10.1111/all.14622 -
International Journal of Infectious... Jul 2020Data are limited on the viral load, viral shedding patterns, and potential infectivity of asymptomatic patients (APs) with coronavirus disease 2019 (COVID-19). This...
Data are limited on the viral load, viral shedding patterns, and potential infectivity of asymptomatic patients (APs) with coronavirus disease 2019 (COVID-19). This study included 31 adult patients who were virologically confirmed to have COVID-19 but were asymptomatic on admission. Among these 31 patients, 22 presented symptoms after admission and were defined as asymptomatic patients in the incubation period (APIs); the other nine patients remained asymptomatic during hospitalization and were defined as asymptomatic patients (APs). The median cycle threshold (Ct) value of APs (39.0, interquartile range (IQR) 37.5-39.5) was significantly higher than that of APIs (34.5, IQR 32.2-37.0), indicating a lower viral load in APs. However, the duration of viral shedding remained similar in the two groups (7 days, IQR 5-14 days vs. 8 days, IQR 5-16 days). The study findings demonstrated that although APs with COVID-19 have a lower viral load, they still have certain period of viral shedding, which suggests the possibility of transmission during their asymptomatic period. Further longitudinal surveillance of these asymptomatic cases via virus nucleic acid testing are warranted.
Topics: Adult; Asymptomatic Infections; Betacoronavirus; COVID-19; Coronavirus Infections; Humans; Pandemics; Pneumonia, Viral; SARS-CoV-2; Viral Load; Virus Shedding
PubMed: 32437933
DOI: 10.1016/j.ijid.2020.05.030 -
Frontiers in Oncology 2023EBV is a lymphotropic virus, member of the family that asymptomatically infects more than 90% of the human population, establishing a latent infection in memory B... (Review)
Review
EBV is a lymphotropic virus, member of the family that asymptomatically infects more than 90% of the human population, establishing a latent infection in memory B cells. EBV exhibits complex survival and persistence dynamics, replicating its genome through the proliferation of infected B cells or production of the lytic virions. Many studies have documented the infection of T/NK cells by EBV in healthy individuals during and after primary infection. This feature has been confirmed in humanized mouse models. Together these results have challenged the hypothesis that the infection of T/NK cells by EBV could be a triggering event for lymphomagenesis. Extranodal NK/T-cell lymphoma (ENKTCL) and Epstein-Barr virus (EBV)-positive nodal T- and NK-cell lymphoma (NKTCL) are two EBV-associated lymphomas of T/NK cells. These two lymphomas display different clinical, histological and molecular features. However, they share two intriguing characteristics: the association with EBV and a geographical prevalence in East Asia and Latin America. In this review we will discuss the genetic characteristics of EBV in order to understand the possible role of this virus in the oncogenesis of ENKTCL and NKTCL. In addition, the main immunohistological, molecular, cytogenetic and epigenetic differences between ENKTCL and NKTCL will be discussed, as well as EBV differences in latency patterns and other viral molecular characteristics.
PubMed: 37781191
DOI: 10.3389/fonc.2023.1240359