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1.
Sci Rep ; 12(1): 13392, 2022 08 04.
Article in English | MEDLINE | ID: covidwho-1972655

ABSTRACT

Diagnosis of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection has primarily been achieved using reverse transcriptase polymerase chain reaction (RT-PCR) for acute infection, and serology for prior infection. Assay with RT-PCR provides data on presence or absence of viral RNA, with no information on virus replication competence, infectivity, or virus characterisation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is typically not used in clinical virology, despite its potential to provide supplemental data about the presence of viral proteins and thus the potential for replication-competent, transmissible virus. Using the SARS-CoV-2 as a model virus, we developed a fast 'bottom-up' proteomics workflow for discovery of target virus peptides using 'serum-free' culture conditions, providing high coverage of viral proteins without the need for protein or peptide fractionation techniques. This workflow was then applied to Coronaviruses OC43 and 229E, Influenza A/H1N1 and H3N2, Influenza B, and Respiratory Syncytial Viruses A and B. Finally, we created an LC-MS/MS method for targeted detection of the eight-virus panel in clinical specimens, successfully detecting peptides from the SARS-CoV-2 ORF9B and nucleoprotein in RT-PCR positive samples. The method provides specific detection of respiratory viruses from clinical samples containing moderate viral loads and is an important further step to the use of LC-MS/MS in diagnosis of viral infection.


Subject(s)
COVID-19 , Influenza A Virus, H1N1 Subtype , Influenza, Human , COVID-19/diagnosis , Chromatography, Liquid , Humans , Influenza A Virus, H3N2 Subtype , SARS-CoV-2/genetics , Tandem Mass Spectrometry , Viral Proteins
2.
Am J Clin Pathol ; 158(4): 480-487, 2022 10 06.
Article in English | MEDLINE | ID: covidwho-1948149

ABSTRACT

OBJECTIVES: Automated qualitative serology assays often measure quantitative signals that are compared against a manufacturer-defined cutoff for qualitative (positive/negative) interpretation. The current general practice of assessing serology assay performance by overall concordance in a qualitative manner may not detect the presence of analytical shift/drift that could affect disease classifications. METHODS: We describe an approach to defining bias specifications for qualitative serology assays that considers minimum positive predictive values (PPVs) and negative predictive values (NPVs). Desirable minimum PPVs and NPVs for a given disease prevalence are projected as equi-PPV and equi-NPV lines into the receiver operator characteristic curve space of coronavirus disease 2019 serology assays, and the boundaries define the allowable area of performance (AAP). RESULTS: More stringent predictive values produce smaller AAPs. When higher NPVs are required, there is lower tolerance for negative biases. Conversely, when higher PPVs are required, there is less tolerance for positive biases. As prevalence increases, so too does the allowable positive bias, although the allowable negative bias decreases. The bias specification may be asymmetric for positive and negative direction and should be method specific. CONCLUSIONS: The described approach allows setting bias specifications in a way that considers clinical requirements for qualitative assays that measure signal intensity (eg, serology and polymerase chain reaction).


Subject(s)
COVID-19 , Bias , COVID-19/diagnosis , COVID-19 Testing , Humans , Polymerase Chain Reaction , Predictive Value of Tests
3.
Geo Journal of Tourism and Geosites ; 40(1):292-301, 2022.
Article in English | ProQuest Central | ID: covidwho-1766328

ABSTRACT

Today's tourism is undergoing radical changes. Until 2020, the number of people participating in tourism had grown steadily, and no one would have thought that the globally dominant economy would experience such a shock. Many tourism businesses were forced to suspend their activities and not all of them could continue in the future as they had to look for other sources of livelihood. But businesses that succeed in surviving the economic collapse must be prepared to meet the changing needs of tourists after a reopening. The aim of our research is to assess the attitudes of potential tourists towards the issue of tourism security. Within the topic, we sought answers to what responsibilities, if any, they assume related to health security. In our research, we also looked at whether potential tourists expect them to provide their security. Responsible behaviour, as an expectation, is directed primarily at service providers or they may feel safe in a destination due to actions taken by other actors (including the travellers themselves). In a study based on an online questionnaire survey of almost a thousand people, the results were processed by statistical data analysis. Those wishing to travel do not even see the situati on created by the current pandemic as a barrier to traveling. When it comes to security, public safety is considered to be paramount, and the public sector is expected to create it. Health security is only in second place, but the results suggest that the responsibility lies with service providers in this regard. Based on the obtained results, both tourism service providers and destination management organizations can place more emphasis on tourism security and its marketing communication.

4.
Vaccines (Basel) ; 10(3)2022 Mar 14.
Article in English | MEDLINE | ID: covidwho-1742763

ABSTRACT

An increasing body of evidence from both academic and clinical studies shows that time-of-day exposure to antigens might significantly alter and modulate the development of adaptive immune responses. Considering the immense impact of the COVID-19 pandemic on global health and the diminished efficacy of vaccination in selected populations, such as older and immunocompromised patients, it is critical to search for the most optimal conditions for mounting immune responses against SARS-CoV-2. Hence, we conducted an observational study on 435 healthy young adults vaccinated with two doses of BNT162b2 (Pfizer-BioNTech) vaccine to determine whether time-of-day of vaccination influences either the magnitude of humoral response or number of adverse drug reactions (ADR) being reported. We found no significant differences between morning and afternoon vaccination in terms of both titers of anti-Spike antibodies and frequency of ADR in the studied population. In addition, our analysis of data on the occurrence of ADR in 1324 subjects demonstrated that the second administration of vaccine in those with previous SARS-CoV-2 infection was associated with lower incidence of ADR. In aggregate, vaccination against COVID-19 with two doses of BNT162b2 mRNA vaccine is presumed to generate an equally efficient anti-Spike humoral response.

5.
Nutrients ; 13(9)2021 Sep 14.
Article in English | MEDLINE | ID: covidwho-1410474

ABSTRACT

This cross-sectional online survey performed in Poland aimed to improve understanding of how COVID-19 pandemic restrictions affected complementary feeding practices among parents of infants aged 4 to 12 months. Self-selected parents were recruited through the internet. The anonymous questionnaire was opened during two intervals during COVID-19 restrictions. The primary outcome was an assessment of sources of information and infant feeding practices in the context of COVID-19 restrictions. Data from 6934 responders (92.2% mothers) were analyzed. Most responders received information from multiple sources, with other parents, family members, or friends being the most frequently reported (48.6%), followed by webinars and experts' recommendations (40.8%). COVID-19 restrictions largely did not impact the method of feeding, changes in feeding patterns, or complementary feeding introduction, although the latter was more likely to be impacted in families with average versus the best financial situations. Multivariate logistic regression analysis also most consistently showed that parents with a tertiary education and living in a city above 500 k were at higher odds of using webinars/experts' recommendations, internet/apps, and professional expert guides and lower odds of claiming no need to deepen knowledge. This study clarifies major issues associated with complementary feeding practices during the implementation of COVID-19 restrictions in Poland.


Subject(s)
COVID-19 , Diet/statistics & numerical data , Feeding Behavior , Infant Nutritional Physiological Phenomena , Quarantine/statistics & numerical data , Cross-Sectional Studies , Diet Surveys , Female , Humans , Infant , Logistic Models , Male , Parents , Poland , SARS-CoV-2 , Surveys and Questionnaires
6.
Clin Chem Lab Med ; 59(9): 1507-1515, 2021 08 26.
Article in English | MEDLINE | ID: covidwho-1206212

ABSTRACT

With an almost unremittent progression of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections all around the world, there is a compelling need to introduce rapid, reliable, and high-throughput testing to allow appropriate clinical management and/or timely isolation of infected individuals. Although nucleic acid amplification testing (NAAT) remains the gold standard for detecting and theoretically quantifying SARS-CoV-2 mRNA in various specimen types, antigen assays may be considered a suitable alternative, under specific circumstances. Rapid antigen tests are meant to detect viral antigen proteins in biological specimens (e.g. nasal, nasopharyngeal, saliva), to indicate current SARS-CoV-2 infection. The available assay methodology includes rapid chromatographic immunoassays, used at the point-of-care, which carries some advantages and drawbacks compared to more conventional, instrumentation-based, laboratory immunoassays. Therefore, this document by the International Federation for Clinical Chemistry and Laboratory Medicine (IFCC) Taskforce on COVID-19 aims to summarize available data on the performance of currently available SARS-CoV-2 antigen rapid detection tests (Ag-RDTs), providing interim guidance on clinical indications and target populations, assay selection, and evaluation, test interpretation and limitations, as well as on pre-analytical considerations. This document is hence mainly aimed to assist laboratory and regulated health professionals in selecting, validating, and implementing regulatory approved Ag-RDTs.


Subject(s)
Antigens, Viral/immunology , COVID-19/diagnosis , Immunoassay/standards , Point-of-Care Testing/standards , Practice Guidelines as Topic/standards , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Asymptomatic Infections/classification , COVID-19/immunology , COVID-19/virology , Humans
9.
Clin Biochem ; 88: 18-22, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-938839

ABSTRACT

OBJECTIVES: Several guidelines for the evaluation of laboratory tests for severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection have recommended establishing an a priori definition of minimum clinical performance specifications before test selection and method evaluation. METHODS: Using positive (PPV) and negative predictive values (NPV), we constructed a spreadsheet tool for determining the minimum clinical specificity (conditional on NPV or PPV, sensitivity and prevalence) and minimum clinical sensitivity (conditional on NPV or PPV, specificity and prevalence) of tests. RESULTS: At a prevalence of 1%, there are no minimum sensitivity requirements to achieve a desired NPV of 60%-95% for a given clinical specificity above 20%. It is not possible to achieve 60-95% PPV even with 100% clinical sensitivity, except when the clinical specificity is near 100%. The opposite trend is seen in high prevalence settings (60%), where a relatively low minimum clinical sensitivity is required to achieve a desired PPV for a given clinical specificity, and a higher minimum clinical specificity is required to achieve a desired NPV for a given clinical sensitivity. DISCUSSION: The selection of laboratory tests and the testing strategy for SARS-CoV-2 involves delicate trade-offs between NPV and PPV based on prevalence and clinical sensitivity and clinical specificity. Practitioners and health authorities should carefully consider the clinical scenarios under which the test result will be used and select the most appropriate testing strategy that fulfils the a priori defined clinical performance specification.


Subject(s)
COVID-19 Testing/methods , COVID-19 Testing/standards , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/metabolism , Humans , Pandemics , Predictive Value of Tests , Prevalence , SARS-CoV-2/isolation & purification , Sensitivity and Specificity
10.
Clin Chem Lab Med ; 58(7): 1037-1052, 2020 06 25.
Article in English | MEDLINE | ID: covidwho-937253

ABSTRACT

The global coronavirus disease 2019 (COVID-19) has presented major challenges for clinical laboratories, from initial diagnosis to patient monitoring and treatment. Initial response to this pandemic involved the development, production, and distribution of diagnostic molecular assays at an unprecedented rate, leading to minimal validation requirements and concerns regarding their diagnostic accuracy in clinical settings. In addition to molecular testing, serological assays to detect antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are now becoming available from numerous diagnostic manufacturers. In both cases, the lack of peer-reviewed data and regulatory oversight, combined with general misconceptions regarding their appropriate use, have highlighted the importance of laboratory professionals in robustly validating and evaluating these assays for appropriate clinical use. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on COVID-19 has been established to synthesize up-to-date information on the epidemiology, pathogenesis, and laboratory diagnosis and monitoring of COVID-19, as well as to develop practical recommendations on the use of molecular, serological, and biochemical tests in disease diagnosis and management. This review summarizes the latest evidence and status of molecular, serological, and biochemical testing in COVID-19 and highlights some key considerations for clinical laboratories operating to support the global fight against this ongoing pandemic. Confidently this consolidated information provides a useful resource to laboratories and a reminder of the laboratory's critical role as the world battles this unprecedented crisis.


Subject(s)
Clinical Laboratory Techniques/methods , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Betacoronavirus/pathogenicity , Biomarkers , COVID-19 , Clinical Laboratory Services/trends , Coronavirus/pathogenicity , Humans , Laboratories/trends , Pandemics , SARS-CoV-2 , Sensitivity and Specificity
11.
Clin Chem Lab Med ; 58(7): 1053-1062, 2020 06 25.
Article in English | MEDLINE | ID: covidwho-937252

ABSTRACT

Coronavirus disease 2019 (COVID-19) is the third coronavirus outbreak that has emerged in the past 20 years, after severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). One important aspect, highlighted by many global health organizations, is that this novel coronavirus outbreak may be especially hazardous to healthcare personnel, including laboratory professionals. Therefore, the aim of this document, prepared by the COVID-19 taskforce of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), is to provide a set of recommendations, adapted from official documents of international and national health agencies, on biosafety measures for routine clinical chemistry laboratories that operate at biosafety levels 1 (BSL-1; work with agents posing minimal threat to laboratory workers) and 2 (BSL-2; work with agents associated with human disease which pose moderate hazard). We believe that the interim measures proposed in this document for best practice will help minimazing the risk of developing COVID-19 while working in clinical laboratories.


Subject(s)
Containment of Biohazards/methods , Coronavirus Infections/prevention & control , Coronavirus Infections/transmission , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Pneumonia, Viral/transmission , Betacoronavirus/pathogenicity , COVID-19 , Clinical Laboratory Services , Coronavirus/pathogenicity , Disease Outbreaks/prevention & control , Humans , Laboratories , Laboratory Personnel , SARS-CoV-2
13.
Clin Chem Lab Med ; 58(12): 2009-2016, 2020 10 07.
Article in English | MEDLINE | ID: covidwho-835982

ABSTRACT

Routine biochemical and hematological tests have been reported to be useful in the stratification and prognostication of pediatric and adult patients with diagnosed coronavirus disease (COVID-19), correlating with poor outcomes such as the need for mechanical ventilation or intensive care, progression to multisystem organ failure, and/or death. While these tests are already well established in most clinical laboratories, there is still debate regarding their clinical value in the management of COVID-19, particularly in pediatrics, as well as the value of composite clinical risk scores in COVID-19 prognostication. This document by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on COVID-19 provides interim guidance on: (A) clinical indications for testing, (B) recommendations for test selection and interpretation, (C) considerations in test interpretation, and (D) current limitations of biochemical/hematological monitoring of COVID-19 patients. These evidence-based recommendations will provide practical guidance to clinical laboratories worldwide, underscoring the contribution of biochemical and hematological testing to our collective pandemic response.


Subject(s)
Coronavirus Infections/metabolism , Hematologic Tests , International Agencies , Pneumonia, Viral/metabolism , Practice Guidelines as Topic , Adult , Biomarkers/blood , COVID-19 , Cardiovascular Diseases/complications , Child , Coronavirus Infections/blood , Coronavirus Infections/complications , Female , Humans , Male , Multiple Organ Failure/complications , Pandemics , Pneumonia, Viral/blood , Pneumonia, Viral/complications
14.
Clin Chem Lab Med ; 58(12): 2001-2008, 2020 10 07.
Article in English | MEDLINE | ID: covidwho-835981

ABSTRACT

Serological testing for the detection of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emerging as an important component of the clinical management of patients with coronavirus disease 2019 (COVID-19) as well as the epidemiological assessment of SARS-CoV-2 exposure worldwide. In addition to molecular testing for the detection of SARS-CoV-2 infection, clinical laboratories have also needed to increase testing capacity to include serological evaluation of patients with suspected or known COVID-19. While regulatory approved serological immunoassays are now widely available from diagnostic manufacturers globally, there is significant debate regarding the clinical utility of these tests, as well as their clinical and analytical performance requirements prior to application. This document by the International Federation for Clinical Chemistry and Laboratory Medicine (IFCC) Taskforce on COVID-19 provides interim guidance on: (A) clinical indications and target populations, (B) assay selection, (C) assay evaluation, and (D) test interpretation and limitations for serological testing of antibodies against SARS-CoV-2 infection. These evidence-based recommendations will provide practical guidance to clinical laboratories in the selection, verification, and implementation of serological assays and are of the utmost importance as we expand our pandemic response from initial case tracing and containment to mitigation strategies to minimize resurgence and further morbidity and mortality.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/immunology , International Agencies , Practice Guidelines as Topic , Serologic Tests/methods , Antibodies, Viral/immunology , Humans , SARS-CoV-2
15.
Clin Chem Lab Med ; 58(12): 1993-2000, 2020 10 07.
Article in English | MEDLINE | ID: covidwho-835980

ABSTRACT

The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection globally has relied extensively on molecular testing, contributing vitally to case identification, isolation, contact tracing, and rationalization of infection control measures during the coronavirus disease 2019 (COVID-19) pandemic. Clinical laboratories have thus needed to verify newly developed molecular tests and increase testing capacity at an unprecedented rate. As the COVID-19 pandemic continues to pose a global health threat, laboratories continue to encounter challenges in the selection, verification, and interpretation of these tests. This document by the International Federation for Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on COVID-19 provides interim guidance on: (A) clinical indications and target populations, (B) assay selection, (C) assay verification, and (D) test interpretation and limitations for molecular testing of SARS-CoV-2 infection. These evidence-based recommendations will provide practical guidance to clinical laboratories worldwide and highlight the continued importance of laboratory medicine in our collective pandemic response.


Subject(s)
Coronavirus Infections/diagnosis , International Agencies , Molecular Diagnostic Techniques , Pneumonia, Viral/diagnosis , Practice Guidelines as Topic , Betacoronavirus/genetics , Betacoronavirus/physiology , COVID-19 , Humans , Pandemics , SARS-CoV-2
16.
Clin Biochem ; 86: 15-22, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-753771

ABSTRACT

BACKGROUND: The recent global survey promoted by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Taskforce on COVID-19 (coronavirus disease 2019) described staff rostering and organization as significant operational challenges during the COVID-19 pandemic. METHOD: A discrete event simulation was used to explore the impact of different permutations of staff roster, including the number of shifts per day, the number of staff on duty per shift, overall number of staff accessible to work in the laboratory (i.e. overall staff pool), the frequency of shift changes (i.e. number of consecutive days worked), fixed work-rest days and split team arrangement on workplace transmission of COVID-19 by a simulated index staff who acquired the infection from the community over 21 days. Additionally, the impact of workplace social distancing (physical distancing) and use of personal protective equipment (PPE) were investigated. RESULTS: A higher rate of transmission was associated with smaller overall staff pool (expressed as multiples of the number of staff per shift), higher number of shifts per day, higher number of staff per shift, and longer consecutive days worked. Having fixed work-rest arrangement did not significantly reduce the transmission rate unless the workplace outbreak was prolonged. Social distancing and PPE use significantly reduced the transmission rate. CONCLUSION: Laboratories should consider organizing the staff into smaller teams/shift and reduce the number of consecutive days worked. Additionally, our observation aligns with the IFCC biosafety recommendation of monitoring staff health (to detect early infection), split team arrangement, workplace social distancing and use of PPE.


Subject(s)
COVID-19/epidemiology , Pandemics , Personal Protective Equipment , Physical Distancing , SARS-CoV-2 , Workplace , Humans
17.
Clin Chem Lab Med ; 58(9): 1441-1449, 2020 08 27.
Article in English | MEDLINE | ID: covidwho-605894

ABSTRACT

Objectives: The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on COVID-19 conducted a global survey to understand how biochemistry laboratories manage the operational challenges during the coronavirus disease 2019 (COVID-19) pandemic. Materials and methods: An electronic survey was distributed globally to record the operational considerations to mitigate biosafety risks in the laboratory. Additionally, the laboratories were asked to indicate the operational challenges they faced. Results: A total of 1210 valid submissions were included in this analysis. Most of the survey participants worked in hospital laboratories. Around 15% of laboratories restricted certain tests on patients with clinically suspected or confirmed COVID-19 over biosafety concerns. Just over 10% of the laboratories had to restrict their test menu or services due to resource constraints. Approximately a third of laboratories performed temperature monitoring, while two thirds of laboratories increased the frequency of disinfection. Just less than 50% of the laboratories split their teams. The greatest reported challenge faced by laboratories during the COVID-19 pandemic is securing sufficient supplies of personal protective equipment (PPE), analytical equipment, including those used at the point of care, as well as reagents, consumables and other laboratory materials. This was followed by having inadequate staff, managing their morale, anxiety and deployment. Conclusions: The restriction of tests and services may have undesirable clinical consequences as clinicians are deprived of important information to deliver appropriate care to their patients. Staff rostering and biosafety concerns require longer-term solutions as they are crucial for the continued operation of the laboratory during what may well be a prolonged pandemic.


Subject(s)
Betacoronavirus , Coronavirus Infections/prevention & control , Laboratories, Hospital/organization & administration , Laboratories, Hospital/statistics & numerical data , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Surveys and Questionnaires , Body Temperature , COVID-19 , Containment of Biohazards/statistics & numerical data , Disease Outbreaks , Disinfection/statistics & numerical data , Health Workforce/organization & administration , Health Workforce/statistics & numerical data , Humans , Monitoring, Physiologic/statistics & numerical data , Personal Protective Equipment/statistics & numerical data , Risk Management/statistics & numerical data , SARS-CoV-2
18.
Clin Chem Lab Med ; 58(9): 1433-1440, 2020 08 27.
Article in English | MEDLINE | ID: covidwho-605893

ABSTRACT

Objectives: A global survey was conducted by the IFCC Task Force on COVID-19 to better understand how general biochemistry laboratories manage the pre-analytical, analytical and post-analytical processes to mitigate biohazard risks during the coronavirus disease 2019 (COVID-19) pandemic. Methods: An electronic survey was developed to record the general characteristics of the laboratory, as well as the pre-analytical, analytical, post-analytical and operational practices of biochemistry laboratories that are managing clinical samples of patients with COVID-19. Results: A total of 1210 submissions were included in the analysis. The majority of responses came from hospital central/core laboratories that serve hospital patient groups and handle moderate daily sample volumes. There has been a decrease in the use of pneumatic tube transport, increase in hand delivery and increase in number of layers of plastic bags for samples of patients with clinically suspected or confirmed COVID-19. Surgical face masks and gloves are the most commonly used personal protective equipment (PPE). Just >50% of the laboratories did not perform an additional decontamination step on the instrument after analysis of samples from patients with clinically suspected or confirmed COVID-19. A fifth of laboratories disallowed add-on testing on these samples. Less than a quarter of laboratories autoclaved their samples prior to disposal. Conclusions: The survey responses showed wide variation in pre-analytical, analytical and post-analytical practices in terms of PPE adoption and biosafety processes. It is likely that many of the suboptimal biosafety practices are related to practical local factors, such as limited PPE availability and lack of automated instrumentation.


Subject(s)
Betacoronavirus , Coronavirus Infections/prevention & control , Laboratories, Hospital/statistics & numerical data , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Risk Management/statistics & numerical data , Surveys and Questionnaires , COVID-19 , Containment of Biohazards/statistics & numerical data , Disease Outbreaks , Humans , Infection Control/statistics & numerical data , Personal Protective Equipment/statistics & numerical data , SARS-CoV-2 , Specimen Handling/statistics & numerical data
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