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2.
Expert Rev Mol Diagn ; 23(3): 191-198, 2023 03.
Article in English | MEDLINE | ID: covidwho-2270109

ABSTRACT

INTRODUCTION: HIV self-testing (HIVST), whereby an individual performs and interprets their own rapid screening test at home, is another tool to increase the proportion of at-risk individuals who know their status. Globally, HIVST has rapidly been adopted through global partnerships to ensure equitable access to tests in low- and middle-income countries (LMIC). AREA COVERED: This review discusses the regulatory burdens of HIV self-testing within the United States while examining the use of HIV self-tests on a global scale. While the United States only has one approved HIV self-test, numerous tests have been prequalified by the WHO. EXPERT OPINION: Despite the US Food and Drug Administration (FDA) clearance of the first and only self-test in 2012, there have been no other tests that have undergone FDA consideration due to regulatory barriers. This, in turn, has stifled market competition. Despite existing evidence that such programs are an innovative approach to testing hesitant or hard-to-reach populations, high individual test cost and bulky packaging make large-scale, mail-out, and HIV self-testing programs expensive. COVID-19 pandemic has accelerated the public demand for self-testing - HIV self-test programs should capitalize on this to increase the proportion of at-risk people who know their status and are linked to care to contribute to ending the HIV epidemic.


Subject(s)
COVID-19 , HIV Infections , Humans , United States/epidemiology , HIV , Self-Testing , Pandemics , Mass Screening , Reagent Kits, Diagnostic , COVID-19/epidemiology , HIV Infections/diagnosis , HIV Infections/epidemiology
3.
Virol J ; 19(1): 191, 2022 11 18.
Article in English | MEDLINE | ID: covidwho-2123315

ABSTRACT

BACKGROUND: The global pandemic of coronavirus disease 2019 (COVID-19) has led to the development of multiple detection kits by national manufacturers for severe acute respiratory syndrome coronavirus 2 viral nucleic acid testing. The purpose of this study is to evaluate the performance of different kits (i.e., Maccura kit and Sansure kit) in real clinical work using clinical samples, which will help with the optimization of the test kits. METHOD: During the past three months (March-May 2022), 1399 pharyngeal swabs from suspected COVID-19 patients have been initially screened using the Maccura kit in Jilin, China, and the test results were verified using the Sansure kit. The cycle threshold (Ct) values generated by the two kits were compared at different viral load levels. Correlation and consistency of the Ct values were investigated using Spearman correlation, Deming regression, and Bland-Altman plots. The cut-off Ct values of the Maccura kit were recalculated by referencing the result of the Sansure kit as a standard. Furthermore, another 163 pharyngeal swabs from suspected COVID-19 patients were collected to verify the new cut-off values. RESULTS: As a result of the Maccura kit testing, 1192 positive cases and 207 suspected COVID-19 cases were verified. After re-examination by the Sansure kit, 1118 positive cases were confirmed. The difference between the Ct values provided by the two kits was statistically significant, except for the N gene at high viral load. The Ct values obtained from the two kits presented a linear positive correlation. The Maccura kit used new cut-off Ct values of 35.00 (ORF1ab gene) and 35.07 (N gene). Based on that, the validation pass rate for the new cut-off Ct values was 91.41%. CONCLUSION: Since the Maccura kit is found to have false positives in actual clinical work, recalculation of the cut-off values can reduce this occurrence. In order to improve the accuracy of the testing, laboratories should use two kits for COVID-19 testing, and the adjusting and optimizing of the kits for their situation are needed.


Subject(s)
COVID-19 , Nucleic Acids , Humans , SARS-CoV-2/genetics , Reagent Kits, Diagnostic , COVID-19/diagnosis , COVID-19 Testing , Real-Time Polymerase Chain Reaction/methods
4.
Int J Infect Dis ; 111: 233-241, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-2113775

ABSTRACT

OBJECTIVES: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has had a significant impact on global public health systems, making nucleic acid detection an important tool in epidemic prevention and control. Detection kits based on real-time reverse transcriptase PCR (rRT-PCR) have been used widely in clinics, but their analytical sensitivity (limit of detection, LOD) remains controversial. Moreover, there is limited research evaluating the analytical sensitivity of other molecular detection kits. METHODS: In this study, armored ribonucleic acid reference materials developed in-house were used to evaluate the analytical sensitivity of SARS-CoV-2 detection kits approved by the National Medical Products Administration. These were based on rRT-PCR and other molecular detection assays. RESULTS: The percentage retesting required with rRT-PCR kits was as follows: 0%, 7.69%, 15.38%, and 23.08% for samples with concentrations ranging from 50 000 to 781 copies/ml. In total, 93% of rRT-PCR kits had a LOD <1000 copies/ml. Only one kit had an LOD >1000 copies/ml. The LOD of other molecular detection kits ranged from 68 to 2264 copies/ml. CONCLUSIONS: The study findings can help pharmaceutical companies optimize and improve detection kits, guide laboratories in selecting kits, and assist medical workers in their daily work.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Reagent Kits, Diagnostic , Sensitivity and Specificity
5.
BMJ Open ; 12(9): e063703, 2022 09 19.
Article in English | MEDLINE | ID: covidwho-2064169

ABSTRACT

OBJECTIVES: Nigeria reported an upsurge in cholera cases in October 2020, which then transitioned into a large, disseminated epidemic for most of 2021. This study aimed to describe the epidemiology, diagnostic performance of rapid diagnostic test (RDT) kits and the factors associated with mortality during the epidemic. DESIGN: A retrospective analysis of national surveillance data. SETTING: 33 of 37 states (including the Federal Capital Territory) in Nigeria. PARTICIPANTS: Persons who met cholera case definition (a person of any age with acute watery diarrhoea, with or without vomiting) between October 2020 and October 2021 within the Nigeria Centre for Disease Control surveillance data. OUTCOME MEASURES: Attack rate (AR; per 100 000 persons), case fatality rate (CFR; %) and accuracy of RDT performance compared with culture using area under the receiver operating characteristic curve (AUROC). Additionally, individual factors associated with cholera deaths and hospitalisation were presented as adjusted OR with 95% CIs. RESULTS: Overall, 93 598 cholera cases and 3298 deaths (CFR: 3.5%) were reported across 33 of 37 states in Nigeria within the study period. The proportions of cholera cases were higher in men aged 5-14 years and women aged 25-44 years. The overall AR was 46.5 per 100 000 persons. The North-West region recorded the highest AR with 102 per 100 000. Older age, male gender, residency in the North-Central region and severe dehydration significantly increased the odds of cholera deaths. The cholera RDT had excellent diagnostic accuracy (AUROC=0.91; 95% CI 0.87 to 0.96). CONCLUSIONS: Cholera remains a serious public health threat in Nigeria with a high mortality rate. Thus, we recommend making RDT kits more widely accessible for improved surveillance and prompt case management across the country.


Subject(s)
Cholera , Epidemics , Cholera/diagnosis , Cholera/epidemiology , Diarrhea/epidemiology , Disease Outbreaks , Female , Humans , Male , Nigeria/epidemiology , Reagent Kits, Diagnostic , Retrospective Studies
6.
Am J Infect Control ; 50(8): 849-856, 2022 08.
Article in English | MEDLINE | ID: covidwho-2000225

ABSTRACT

BACKGROUND: Health care inequity in remote and rural Indigenous communities often involves difficulty accessing health care services and supplies. Remotely Piloted Aircraft Systems, or drones, offer a potentially cost-effective method for reducing inequity by removing geographic barriers, increasing timeliness, and improving accessibility of supplies, equipment, and remote care. METHODS: We assessed the feasibility of drones for delivery of supplies, medical equipment, and medical treatment across multiple platforms, including drone fleet development and testing; payload system integration (custom fixed-mount, winch, and parachute); and medical delivery simulations (COVID-19 test kit delivery and return, delivery of personal protective equipment, and remote ultrasound delivery and testing). RESULTS: Drone operational development has led to a finalized, scalable fleet of small to large drones with functional standard operating procedures across a range of scenarios, and custom payload systems including a fixed-mount, winch-based and parachute-based system. Simulation scenarios were successful, with COVID-19 test swabs returned to the lab with no signal degradation and a remote ultrasound successfully delivered and remotely guided in the field. DISCUSSION/CONCLUSIONS: Drone-based medical delivery models offer an innovative approach to addressing longstanding issues of health care access and equity and are particularly relevant in the context of SARS-CoV-2.


Subject(s)
COVID-19 , Reagent Kits, Diagnostic , Aircraft , COVID-19 Testing , Humans , SARS-CoV-2 , Unmanned Aerial Devices
7.
Viruses ; 14(9)2022 08 24.
Article in English | MEDLINE | ID: covidwho-1997807

ABSTRACT

Significant efforts are being made in many countries around the world to respond to the COVID-19 pandemic by developing diagnostic reagent kits, identifying infected people, determining treatment methods, and finally producing effective vaccines. However, novel coronavirus variants may potentially reduce the effectiveness of all these efforts, demonstrating increased transmissibility and abated response to therapy or vaccines, as well as the possibility of false negative results in diagnostic procedures based on nucleic acid amplification methods. Since the end of 2020, several variants of concern have been discovered around the world. When information about a new, potentially more dangerous strain of pathogen appears, it is crucial to determine the moment of its emergence in a region. Eventually, that permits taking timely measures and minimizing new risks associated with the spreading of the virus. Therefore, numerous nations have made tremendous efforts to identify and trace these virus variants, which necessitates serious technological processes to sequence a large number of viral genomes. Here, we report on our experience as one of the primary laboratories involved in monitoring SARS-CoV-2 variants in Russia. We discuss the various approaches used, describe effective protocols, and outline a potential technique combining several methods to increase the ability to trace genetic variants while minimizing financial and labor costs.


Subject(s)
COVID-19 , Nucleic Acids , COVID-19/diagnosis , COVID-19 Vaccines , Humans , Pandemics/prevention & control , Reagent Kits, Diagnostic , SARS-CoV-2/genetics
8.
Biosensors (Basel) ; 12(9)2022 Aug 23.
Article in English | MEDLINE | ID: covidwho-1997517

ABSTRACT

In the present work, highly multiplexed diagnostic KITs based on an Interferometric Optical Detection Method (IODM) were developed to evaluate six Coronavirus Disease 2019 (COVID-19)-related biomarkers. These biomarkers of COVID-19 were evaluated in 74 serum samples from severe, moderate, and mild patients with positive polymerase chain reaction (PCR), collected at the end of March 2020 in the Hospital Clínico San Carlos, in Madrid (Spain). The developed multiplexed diagnostic KITs were biofunctionalized to simultaneously measure different types of specific biomarkers involved in COVID-19. Thus, the serum samples were investigated by measuring the total specific Immunoglobulins (sIgT), specific Immunoglobulins G (sIgG), specific Immunoglobulins M (sIgM), specific Immunoglobulins A (sIgA), all of them against SARS-CoV-2, together with two biomarkers involved in inflammatory disorders, Ferritin (FER) and C Reactive Protein (CRP). To assess the results, a Multiple Linear Regression Model (MLRM) was carried out to study the influence of IgGs, IgMs, IgAs, FER, and CRP against the total sIgTs in these serum samples with a goodness of fit of 73.01% (Adjusted R-Squared).


Subject(s)
COVID-19 Testing , COVID-19 , Biomarkers , C-Reactive Protein , COVID-19/diagnosis , COVID-19 Testing/instrumentation , Ferritins , Humans , Immunoglobulin A, Secretory , Reagent Kits, Diagnostic , SARS-CoV-2
9.
J Pharm Sci ; 111(10): 2674-2686, 2022 10.
Article in English | MEDLINE | ID: covidwho-1937315

ABSTRACT

The term "Medical devices" includes technology-based devices or articles, both basic and complex. Due to these types of variations, a strict, robust, transparent, and sustainable regulatory framework is required. In recent clinical practice, incidents including the breast implant and the hip replacement crisis have made it necessary to improve the regulatory and compliance approaches for the industry to ensure the manufacturing and distribution of safe and innovative MDs within the EU. In response to this, the EU revised the laws governing medical devices and in vitro diagnostics to align with the developments of the sector, address critical safety issues and support innovation. The new regulation (EU) 2017/745 on Medical Devices (MDR) is now applicable from May 26 2021 and the In Vitro Diagnostic Medical Devices Regulation (EU) 2017/746 will take effect from May 2022.In this review, we aim to provide an update on the new Medical Device Regulations in the context of the current medical needs of the world, and also to give a glimpse at the non-EU regulatory landscape. Finally, we take a look at the closed-system transfer devices (CSTD) and COVID facilitated changes promoting demand for continuous improvement and trends in the pharmaceutical and medical industry related areas.


Subject(s)
COVID-19 , Medical Device Legislation , COVID-19/epidemiology , Commerce , Humans , Pharmaceutical Preparations , Reagent Kits, Diagnostic
10.
Proc Natl Acad Sci U S A ; 119(26): e2202034119, 2022 06 28.
Article in English | MEDLINE | ID: covidwho-1900769

ABSTRACT

CRISPR diagnostics based on nucleic acid amplification faces barriers to its commercial use, such as contamination risks and insufficient sensitivity. Here, we propose a robust solution involving optochemical control of CRISPR RNA (crRNA) activation in CRISPR detection. Based on this strategy, recombinase polymerase amplification (RPA) and CRISPR-Cas12a detection systems can be integrated into a completely closed test tube. crRNA can be designed to be temporarily inactivated so that RPA is not affected by Cas12a cleavage. After the RPA reaction is completed, the CRISPR-Cas12a detection system is activated under rapid light irradiation. This photocontrolled, fully closed CRISPR diagnostic system avoids contamination risks and exhibits a more than two orders of magnitude improvement in sensitivity compared with the conventional one-pot assay. This photocontrolled CRISPR method was applied to the clinical detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, achieving detection sensitivity and specificity comparable to those of PCR. Furthermore, a compact and automatic photocontrolled CRISPR detection device was constructed.


Subject(s)
Bacterial Proteins , CRISPR-Associated Proteins , CRISPR-Cas Systems , Clustered Regularly Interspaced Short Palindromic Repeats , Endodeoxyribonucleases , Reagent Kits, Diagnostic , Reverse Transcriptase Polymerase Chain Reaction , COVID-19/diagnosis , Clustered Regularly Interspaced Short Palindromic Repeats/radiation effects , Humans , RNA/radiation effects , Recombinases/genetics , Reverse Transcriptase Polymerase Chain Reaction/methods , SARS-CoV-2/isolation & purification , Sensitivity and Specificity
11.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(1): 36-40, 2022 Feb 23.
Article in Chinese | MEDLINE | ID: covidwho-1893447

ABSTRACT

OBJECTIVE: To evaluate the diagnostic efficiency of four anti-cysticercus IgG, IgG4 or IgM antibody test kits (enzyme-linked immunosorbent assay, ELISA) by different manufacturers, so as to provide insights into the epidemiological investigation and clinical detection of cysticercosis. METHODS: Forty serum samples from cerebral cysticercosis patients, 100 serum samples from healthy volunteers, 30 serum samples from paragonimiasis skrjabini patients, 17 serum samples from cystic echinococcosis and 19 serum samples from subcutaneous or cerebral sparganosis patients were collected and detected using anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) and the anti-cysticercus IgG antibody test kit (brand B). The sensitivity, specificity and false negative rate of the four kits for detection of cysticercosis were estimated. RESULTS: The anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) showed 95.00% (38/40), 87.50% (35/40), 7.50% (3/40) sensitivities and 98.00% (98/100), 100.00% (100/100) and 100.00% (100/100) for detection of cysticercosis, while the anti-cysticercus IgG antibody test kit (brand B) presented a 75.00% (30/40) sensitivity and 100.00% (100/100) specificity for detection of cysticercosis. The sensitivity for detection of cysticercosis was significantly higher by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ2 = 6.28, P < 0.05); however, no significant difference was seen in the specificity by two kits (χ2 = 2.01, P > 0.05). The four ELISA kits showed overall false positive rates of 37.88% (25/66), 22.73% (15/66), 62.12% (41/66) and 15.15% (10/66) for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 37.61, P < 0.05), and the anti-cysticercus IgG antibody test kit (brand A) presented the highest overall false positive rate for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 7.56, P' < 0.008), while a higher overall false positive rate was seen for detection of paragonimiasis, echinococcosis and sparganosis by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ2 = 8.75, P' < 0.008). The four ELISA kits showed false positive rates of 40.00% (12/30), 16.67% (5/30), 76.67% (23/30) and 13.33% (4/30) for detection of paragonimiasis (χ2 = 32.88, P < 0.05) and 21.05% (4/19), 26.32% (5/19), 73.68% (14/19) and 15.79% (3/19) for detection of sparganosis (χ2 = 19.97, P < 0.05), and the highest false positive rates were found by the anti-cysticercus IgM antibody test kit (brand A) for detection of paragonimiasis and sparganosis (all P' < 0.008). However, the four ELISA kits showed comparable false positive rates of 52.94% (9/17), 29.41% (5/17), 23.53% (4/17) and 17.65% (3/17) for detection of echinococcosis (χ2 = 8.24, P > 0.05). In addition, the anti-cysticercus IgM anti-body test kit (brand A) showed false positive rates of 76.67% (23/30), 23.53% (4/17) and 73.68% (14/19) for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 14.537, P < 0.05), with the lowest false positive rate seen for detection of echinococcosis (χ2 = 14.537, P' < 0.014), while no significant differences were seen in the false positive rate for detection of paragonimiasis, echinococcosis and sparganosis by other three ELISA kits (all P > 0.05). CONCLUSIONS: The four anti-cysticercus IgG, IgG4 or IgM antibody test kits exhibit various efficiencies for serodiagnosis of cysticercosis. The anti-cysticercus IgG antibody test kit (brand A) has a high sensitivity for serodiagnosis of cysticercosis; however, it still needs to solve the problems of cross-reaction with other parasitic diseases and stability.


Subject(s)
Cysticercosis , Cysticercus , Animals , Antibodies, Helminth , Cysticercosis/diagnosis , Enzyme-Linked Immunosorbent Assay , Humans , Reagent Kits, Diagnostic , Sensitivity and Specificity , Serologic Tests
12.
PLoS Med ; 19(3): e1003930, 2022 03.
Article in English | MEDLINE | ID: covidwho-1793652

ABSTRACT

BACKGROUND: Low syphilis testing uptake is a major public health issue among men who have sex with men (MSM) in many low- and middle-income countries. Syphilis self-testing (SST) may complement and extend facility-based testing. We aimed to evaluate the effectiveness and costs of providing SST on increasing syphilis testing uptake among MSM in China. METHODS AND FINDINGS: An open-label, parallel 3-arm randomized controlled trial (RCT) was conducted between January 7, 2020 and July 17, 2020. Men who were at least 18 years of age, had condomless anal sex with men in the past year, reported not testing for syphilis in the last 6 months, and had a stable residence with mailing addresses were recruited from 124 cities in 26 Chinese provinces. Using block randomization with blocks of size 12, enrolled participants were randomly assigned (1:1:1) into 3 arms: standard of care arm, standard SST arm, and lottery incentivized SST arm (1 in 10 chance to win US$15 if they had a syphilis test). The primary outcome was the proportion of participants who tested for syphilis during the trial period and confirmed with photo verification and between arm comparisons were estimated with risk differences (RDs). Analyses were performed on a modified intention-to-treat basis: Participants were included in the complete case analysis if they had initiated at least 1 follow-up survey. The Syphilis/HIV Duo rapid test kit was used. A total of 451 men were enrolled. In total, 136 (90·7%, 136/150) in the standard of care arm, 142 (94·0%, 142/151) in the standard of SST arm, and 137 (91·3%, 137/150) in the lottery incentivized SST arm were included in the final analysis. The proportion of men who had at least 1 syphilis test during the trial period was 63.4% (95% confidence interval [CI]: 55.5% to 71.3%, p = 0.001) in the standard SST arm, 65.7% (95% CI: 57.7% to 73.6%, p = 0.0002) in the lottery incentivized SST arm, and 14.7% (95% CI: 8.8% to 20.7%, p < 0.001) in the standard of care arm. The estimated RD between the standard SST and standard of care arm was 48.7% (95% CI: 37.8% to 58.4%, p < 0.001). The majority (78.5%, 95% CI: 72.7% to 84.4%, p < 0.001) of syphilis self-testers reported never testing for syphilis. The cost per person tested was US$26.55 for standard SST, US$28.09 for the lottery incentivized SST, and US$66.19 for the standard of care. No study-related adverse events were reported during the study duration. Limitation was that the impact of the Coronavirus Disease 2019 (COVID-19) restrictions may have accentuated demand for decentralized testing. CONCLUSIONS: Compared to standard of care, providing SST significantly increased the proportion of MSM testing for syphilis in China and was cheaper (per person tested). TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900022409.


Subject(s)
HIV Infections/diagnosis , Homosexuality, Male , Patient Participation/methods , Self-Testing , Syphilis/diagnosis , Adolescent , Adult , COVID-19/epidemiology , China/epidemiology , Follow-Up Studies , HIV Infections/prevention & control , Health Services Accessibility/organization & administration , Homosexuality, Male/statistics & numerical data , Humans , Immunoassay/methods , Male , Mass Screening/economics , Mass Screening/methods , Mass Screening/organization & administration , Middle Aged , Motivation , Pandemics , Reagent Kits, Diagnostic/economics , Reagent Kits, Diagnostic/supply & distribution , SARS-CoV-2 , Sexual and Gender Minorities/statistics & numerical data , Syphilis/epidemiology , Syphilis/prevention & control , Young Adult
13.
Klin Lab Diagn ; 65(11): 683-687, 2020 Dec 04.
Article in English | MEDLINE | ID: covidwho-1780382

ABSTRACT

A new original Russian test kit for the detection of IgG-antibodies to the causative agent of COVID-19 - coronavirus SARS-CoV-2 by the method of enzyme-linked immunosorbent assay (ELISA) on a solid-phase «ELISA-SARS-CoV-2-AT-G¼ has been developed. In comparative tests with similar test systems «Vitrotest® SARS-CoV-2 IgG¼ (Vitrotest, Ukraine) and «Anti-SARS-Cov-2 ELISA (IgG)¼ (EUROIMMUN AG, Germany) high diagnostic efficiency of the new test system was shown.


Subject(s)
Antibodies, Viral/analysis , COVID-19 Serological Testing , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay , Immunoglobulin G/analysis , Clinical Laboratory Techniques , Humans , Plasma , Reagent Kits, Diagnostic
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