This document updates recommendations for HIV testing by laboratories in the United States and offers approaches for reporting test results to persons ordering HIV tests and to public health authorities. The recommended algorithm is a sequence of tests used in combination to improve the accuracy of ...the laboratory diagnosis of HIV based on testing of serum or plasma specimens. The updated recommendations also include tests for HIV antigens and HIV nucleic acid because studies from populations at high risk for HIV demonstrate that antibody testing alone might miss a considerable percentage of HIV infections detectable by virologic tests
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Dispatches
DOI: http://dx.doi.org/10.3201/eid2203.151607
Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 22, No. 3, March 2016
Автоматизированная технология амплификации нуклеиновых кислот в режиме реального времени для быстрого и одновременного выявления туберкулеза и устойчивости к р...ифампицину: система Xpert MTB/RIF.
Программное заявление.
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This document provides brief information answering common questions regarding COVID-19 diagnostic tests and how to prioritize them to the patients most in need.
The speed of developing diagnostics for SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19), has been quite remarkable. Diagnostics have focused on nucleic acid amplification testing (NAAT) to identify infected individuals in acute-phase disease for timely implementation of mitiga...tion strategies and case management. More and more immunodiagnostics, mostly rapid diagnostic tests, are being made available as an alternative to NAATs. This type of test can be used out-of-laboratory conditions at large scale.
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6 July 2021. Three new nucleic acid amplification test (NAAT) classes are endorsed by WHO and included.
The latest operational handbook includes the new classes recommended by WHO. It aims at facilitating the implementation of the WHO recommendations by the Member States, technical partners, and ot...hers involved in managing patients with TB and DR-TB. The operational handbook provides practical information on existing and new tests recommended by WHO, step-by-step advice on implementing and scale-up testing to achieve local and national impact and lastly, model diagnostic algorithms, which are updated to incorporate the latest recommendations. An overview of budgetary considerations and information sheets on each of the newly recommended tests is provided.
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Interim guidance, 6 October 2021
Direct detection of SARS-CoV-2 viral proteins (antigens) in nasal swabs and other respiratory secretions using lateral flow immunoassays (also known as rapid diagnostic tests, RDTs) offers a faster and less expensive method to test for SARS-CoV-2 than the reference ...method, nucleic acid amplification tests (NAATs). This interim guidance offers recommendations on the priority uses of antigen-detecting rapid diagnostic tests (Ag-RDTs) in specific populations and settings, including (i) for primary case detection in symptomatic individuals suspected to be infected and asymptomatic individuals at high risk of COVID-19, (ii) for contact tracing, (iii) during outbreak investigations and (iv) to monitor trends of disease incidence in communities. Ag-RDTs meeting minimum performance requirements can be used outside of clinical and laboratory settings, including in communities, by trained operators in accordance with instructions. The guidance additionally provides recommendations on implementation, product selection and storage.
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Available in Arabic, Chinese, English, French, Portuguese and Spanish
https://apps.who.int/iris/handle/10665/334254
The purpose of this document is to provide guidance on the use of pooled sample testing strategy in coronavirus disease (COVID-19)
testing laboratories of the African Union Member States for scaling up SARS-CoV-2 nucleic acid testing capacity with the available resources. The current document descr...ibes the effect of factors such as the prevalence of COVID-19 in the population to be tested, the homogeneity of pools, and the sensitivity of the molecular test in optimal pool size determination. It also highlights the importance of monitoring the prevalence of COVID-19 in a population to be tested and proper validation of the test, to limit the potential for false-negative results. Validation studies to determine the optimal pool size by testing laboratories are recommended as the optimum approach. A safe, simple ‘two-stage pooling’ option has been indicated in this guidance to be used by laboratories until such validation can be achieved.
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All vaccines work by exposing the body to molecules from the target pathogen to trigger an immune response – but the method of exposure varies. Here’s how DNA and RNA vaccines work.
In 2019, an estimated 10 million individuals fell ill with tuberculosis (TB) and 3 million of them were not reported to have beendiagnosed and notified. The gap is proportionately even wider for drug-resistant TB. Of the estimated 465 000 patients with rifampicin-resistant and multi-drug resistant T...B (RR/MDR-TB), only 206 030 (44%) were diagnosed and notified.For the first time, the World Health Organization (WHO) has provided global estimates of the incidence of isoniazid resistance: in 2019, there were 1.4 million incident cases of isoniazid-resistant TB, of which 1.1 million were susceptible to rifampicin. Most of these people were not diagnosed with drug-resistant TB and did not receive appropriate treatment.
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6 July 2021. The “WHO consolidated guidelines on tuberculosis. Module 3: Diagnosis - Rapid diagnostics for tuberculosis detection 2021 update” is the latest document replacing the one issued in 2020. Three new nucleic acid amplification test (NAAT) classes are endorsed by WHO and included in the... latest consolidated guideline
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Se estima que unos 10 millones de personas contrajeron tuberculosis (TB) en el 2019 y que a unos 3 millones de ellas no se les diagnosticó ni se les notificó la enfermedad. Con el propósito de poner fin a la epidemia mundial de la tuberculosis para el 2030, sigue siendo necesario ampliar la capac...idad para analizar un gran número de muestras.
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El agente etiológico de la tuberculosis es el Mycobacterium tuberculosis o bacilo de Koch. Se trata de un bacilo aerobio estricto, ácido-alcohol resistente, sin movilidad, de crecimiento lento y que se inactiva con rayos ultravioleta y temperaturas mayores de 60°C.
Any individual that meets the suspected case definition of monkeypox should be offered testing in appropriately equipped laboratories by staff trained in the relevant technical and safety procedures. Confirmation of monkeypox virus infection is based on nucleic acid amplification testing (NAAT), usi...ng real-time or conventional polymerase chain reaction (PCR), for detection of unique sequences of viral DNA. PCR can be used alone, or in combination with sequencing. The recommended specimen type for laboratory confirmation of monkeypox is skin lesion material, including swabs of lesion surface and/or exudate, roofs from more than one lesion, or lesion crusts.
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These guidelines provide updated evidence-based recommendations on the priority HCV-related topics from the 2018 WHO Guidelines for the care and treatment of persons diagnosed with chronic hepatitis C infection and the 2017 WHO Guidelines on hepatitis B and C testing. These priority areas are:
... direct-acting antiviral (DAA) treatment of adolescents and children ages ≥3 years of age
simplified HCV service delivery (decentralization, integration and task sharing)
HCV diagnostics – use of point-of-care (POC) HCV ribonucleic acid (RNA) assays and reflex HCV RNA testing.
These guidelines also update existing chapters without new recommendations, such as the inclusion of new manufacturers’ protocols on the use of dried blood spot (DBS) for HCV RNA testing and new data to inform the limit of detection for HCV RNA assays as a test of cure, in addition to their use for diagnosis.
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For the molecular diagnosis of Chagas disease by real-time PCR (polymerase chain reaction), optimization of diagnostic accuracy is desirable. The detection limit of real-time PCR assays for the diagnosis of Trypanosoma cruzi in human serum is affected by various influences including the choice of th...e nucleic acid extraction assay. In this study, three nucleic acid extraction assays were compared regarding their influence on the sensitivity of a T. cruzi-specific real-time PCR with 62 reference sera containing T. cruzi target DNA (deoxyribonucleotide acid). More than 95% of the positive sera were correctly identified after all three nucleic acid extraction strategies with a detection rate ranging from 96.8% (60/62) for the worst assay to 100% (62/62) for the best one. A matched pairs analysis for the comparison of the cycle threshold (Ct) values obtained with the 59 reference samples with positive real-time PCR results after all three nucleic acid extraction schemes indicated differences in a range of about 3 Ct steps. Summarized, all three compared nucleic acid extraction schemes were basically suitable for T. cruzi-specific PCR from serum with some minor differences. However, in the case of low quantities of circulating parasite DNA in the serum of a patient with Chagas disease, even minor effects can make a difference in the individual diagnosis.
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