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1.
Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology ; 2023.
Article in English | EuropePMC | ID: covidwho-2254122

ABSTRACT

Background : The COVID-19 pandemic led to severe health systems collapse, as well as logistics and supply delivery shortages across sectors. Delivery of PCR related healthcare supplies continue to be hindered. There is the need for a rapid and accessible SARS-CoV-2 molecular detection method in low resource settings. Objectives : To validate a novel isothermal amplification method for rapid detection of SARS-CoV-2 across seven sub-Sharan African countries. Study design : In this multi-country phase 2 diagnostic study, 3,231 clinical samples in seven African sites were tested with two reverse transcription Recombinase-Aided Amplification (RT-RAA) assays (based on SARS-CoV-2 Nucleocapsid (N) gene and RNA-dependent RNA polymerase (RdRP) gene). The test was performed in a mobile suitcase laboratory within 15 minutes. All results were compared to a real-time RT-PCR assay. Extraction kits based on silica gel or magnetic beads were applied. Results : Four sites demonstrated good to excellent agreement, while three sites showed fair to moderate results. The RdRP gene assay exhibited an overall PPV of 0.92 and a NPV of 0.88. The N gene assay exhibited an overall PPV of 0.93 and a NPV 0.88. The sensitivity of both RT-RAA assays varied depending on the sample Ct values. When comparing sensitivity between sites, values differed considerably. For high viral load samples, the RT-RAA assay sensitivity ranges were between 60.5 and 100% (RdRP assay) and 25 and 98.6 (N assay). Conclusion : Overall, the RdRP based RT-RAA test showed the best assay accuracy. This study highlights the challenges of implementing rapid molecular assays in field conditions. Factors that are important for successful deployment across countries include the implementation of standardized operation procedures, in-person continuous training for staff, and enhanced quality control measures.

2.
J Clin Virol ; 162: 105422, 2023 05.
Article in English | MEDLINE | ID: covidwho-2254123

ABSTRACT

BACKGROUND: The COVID-19 pandemic led to severe health systems collapse, as well as logistics and supply delivery shortages across sectors. Delivery of PCR related healthcare supplies continue to be hindered. There is the need for a rapid and accessible SARS-CoV-2 molecular detection method in low resource settings. OBJECTIVES: To validate a novel isothermal amplification method for rapid detection of SARS-CoV-2 across seven sub-Sharan African countries. STUDY DESIGN: In this multi-country phase 2 diagnostic study, 3,231 clinical samples in seven African sites were tested with two reverse transcription Recombinase-Aided Amplification (RT-RAA) assays (based on SARS-CoV-2 Nucleocapsid (N) gene and RNA-dependent RNA polymerase (RdRP) gene). The test was performed in a mobile suitcase laboratory within 15 min. All results were compared to a real-time RT-PCR assay. Extraction kits based on silica gel or magnetic beads were applied. RESULTS: Four sites demonstrated good to excellent agreement, while three sites showed fair to moderate results. The RdRP gene assay exhibited an overall PPV of 0.92 and a NPV of 0.88. The N gene assay exhibited an overall PPV of 0.93 and a NPV 0.88. The sensitivity of both RT-RAA assays varied depending on the sample Ct values. When comparing sensitivity between sites, values differed considerably. For high viral load samples, the RT-RAA assay sensitivity ranges were between 60.5 and 100% (RdRP assay) and 25 and 98.6 (N assay). CONCLUSION: Overall, the RdRP based RT-RAA test showed the best assay accuracy. This study highlights the challenges of implementing rapid molecular assays in field conditions. Factors that are important for successful deployment across countries include the implementation of standardized operation procedures, in-person continuous training for staff, and enhanced quality control measures.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/diagnosis , Pandemics , Sensitivity and Specificity , Nucleic Acid Amplification Techniques/methods , Real-Time Polymerase Chain Reaction , Africa South of the Sahara , RNA, Viral/genetics
3.
Qatar Med J ; 2022(4): 52, 2022.
Article in English | MEDLINE | ID: covidwho-2233324

ABSTRACT

BACKGROUND: The novel coronavirus disease 2019 (COVID-19) pandemic has had consequences on the pregnant population, as disease severity is associated with the quality of maternal health and pregnancy complications, increasing maternal and neonatal morbidity. Worldwide descriptive data help describe risk factors that could predict symptomatic and severe COVID-19 in pregnancy. OBJECTIVES: To describe demographic features and risk factors of pregnant women with COVID-19 in Qatar and compare symptomatic versus asymptomatic disease. STUDY DESIGN AND METHODOLOGY: Clinical characteristics and risk factors of pregnant women with COVID-19 in Qatar from March 2020 to March 2021 was retrospectively reviewed, comparing the cohort with the general pregnant population. Crude and adjusted odds ratios (aORs) were computed, comparing symptomatic versus asymptomatic infection. RESULTS: Of the 500 women, 347 reported at least one symptom at diagnosis (347/500; 69.4%). The majority fell in the 30-39 years age group (241/500; 48%), with more than half in the obese body mass index (BMI) category. The cohort was 66% (332/500) Qatari women, compared with the 26% expected in the population (26.4% vs 66.4% p < 0.001). Compared with the 2019 national statistics, the number of women was higher in the >40 years age group (5% vs 7.6%, p = 0.027) and grand multiparous group (5.4% vs 13.6%, p < 0.001). The symptom most commonly reported by the symptomatic group was cough (276/500; 55%), followed by fever, fatigue, and myalgia. In the adjusted analysis, the symptomatic group had 2.7 times higher odds of being asthmatic (OR = 2.67, 95% CI 1.1-6.7, p = 0.037). Women aged >40 years had 6.6 times higher odds of symptomatic disease (aOR = 6.6, 95% CI 1.08-39.73, p = 0.041). A history of contact with a patient with symptomatic COVID and earlier gestational age at diagnosis increased the odds (aOR = 2.06, 95% CI 1.2-3.54, p = 0.009; aOR = 0.73 95% CI 0.57-0.96; p = 0.017). CONCLUSIONS: This study cohort included significantly more Qatari women, older women, grand multiparous women, a higher proportion with pre-existing and gestational diabetes, and higher BMI than national data. In addition, contact to a patient with symptomatic disease, history of asthma, older age, and earlier gestational age at diagnosis were significantly associated with symptomatic disease.

4.
Qatar medical journal ; 2022(4), 2022.
Article in English | EuropePMC | ID: covidwho-2147502

ABSTRACT

Background: The novel coronavirus disease 2019 (COVID-19) pandemic has had consequences on the pregnant population, as disease severity is associated with the quality of maternal health and pregnancy complications, increasing maternal and neonatal morbidity. Worldwide descriptive data help describe risk factors that could predict symptomatic and severe COVID-19 in pregnancy. Objectives: To describe demographic features and risk factors of pregnant women with COVID-19 in Qatar and compare symptomatic versus asymptomatic disease. Study design and methodology: Clinical characteristics and risk factors of pregnant women with COVID-19 in Qatar from March 2020 to March 2021 was retrospectively reviewed, comparing the cohort with the general pregnant population. Crude and adjusted odds ratios (aORs) were computed, comparing symptomatic versus asymptomatic infection. Results: Of the 500 women, 347 reported at least one symptom at diagnosis (347/500;69.4%). The majority fell in the 30–39 years age group (241/500;48%), with more than half in the obese body mass index (BMI) category. The cohort was 66% (332/500) Qatari women, compared with the 26% expected in the population (26.4% vs 66.4% p < 0.001). Compared with the 2019 national statistics, the number of women was higher in the >40 years age group (5% vs 7.6%, p = 0.027) and grand multiparous group (5.4% vs 13.6%, p < 0.001). The symptom most commonly reported by the symptomatic group was cough (276/500;55%), followed by fever, fatigue, and myalgia. In the adjusted analysis, the symptomatic group had 2.7 times higher odds of being asthmatic (OR = 2.67, 95% CI 1.1–6.7, p = 0.037). Women aged >40 years had 6.6 times higher odds of symptomatic disease (aOR = 6.6, 95% CI 1.08–39.73, p = 0.041). A history of contact with a patient with symptomatic COVID and earlier gestational age at diagnosis increased the odds (aOR = 2.06, 95% CI 1.2–3.54, p = 0.009;aOR = 0.73 95% CI 0.57–0.96;p = 0.017). Conclusions: This study cohort included significantly more Qatari women, older women, grand multiparous women, a higher proportion with pre-existing and gestational diabetes, and higher BMI than national data. In addition, contact to a patient with symptomatic disease, history of asthma, older age, and earlier gestational age at diagnosis were significantly associated with symptomatic disease.

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