A major challenge in controlling the COVID-19 pandemic is the high false-negative rate of the commonly used RT-PCR methods for SARS-CoV-2 detection in clinical samples. Accurate detection is particularly challenging in samples with low viral loads that are below the limit of detection (LoD) of standard one- or two-step RT-PCR methods. In this study, we implemented a three-step approach for SARS-CoV-2 detection and quantification that employs reverse transcription, targeted cDNA preamplification, and nano-scale qPCR based on a commercially available microfluidic chip. Using SARS-CoV-2 synthetic RNA and plasmid controls, we demonstrate that the addition of a preamplification step enhances the LoD of this microfluidic RT-qPCR by 1000-fold, enabling detection below 1 copy/µL. We applied this method to analyze 182 clinical NP swab samples previously diagnosed using a standard RT-qPCR protocol (91 positive, 91 negative) and demonstrate reproducible and quantitative detection of SARS-CoV-2 over five orders of magnitude (<1 to 106 viral copies/µL). Crucially, we detect SARS-CoV-2 with relatively low viral load estimates (<1 to 40 viral copies/µL) in 17 samples with negative clinical diagnosis, indicating a potential false-negative rate of 18.7% by clinical diagnostic procedures. In summary, this three-step nano-scale RT-qPCR method can robustly detect SARS-CoV-2 in samples with relatively low viral loads (<1 viral copy/µL) and has the potential to reduce the false-negative rate of standard RT-PCR-based diagnostic tests for SARS-CoV-2 and other viral infections.
A questionnaire was devised to gain information about feeding history, cooking facilities, home conditions, and daily food and drink intake. The questionnaire was completed in the homes of families by a Bangladeshi nurse employed for this purpose. The families were chosen at random by health visitors during a 6-month period. As ages ranged from 6 months to 4 years 9 months, the children were subdivided into the following groups: group 1, 6 months to 1 year; group 2, 1-2 years; group 3, 2-3 years; and group 4, 3-5 years.Information on the child's diet and feeding pattern was obtained using the quantitative 7-day diet history method. The estimation of quantities was based on household measures, and this should be taken into account when considering the results.The
Non-communicable diseases (NCDs) are the leading cause of mortality in all Gulf Cooperation Council (GCC) member countries and place substantial economic burden on the governments and the people. The escalating demand for NCD-related health services takes an enormous toll on health systems in the GCC countries. There is an urgent need to make significant advances in the healthcare infrastructure and develop strategies to overcome the NCD challenge. This review aims to provide the current status of national healthcare systems and national NCD policies in the GCC member countries to highlight the challenges and identify opportunities towards strengthening NCD management and control. The PubMed database, the World Health Organization website and Ministry of Health websites of GCC member countries were searched to identify relevant information. Future strategies and investments in healthcare infrastructure to overcome the NCD challenge include continuing high-level commitment towards multisectoral actions, redesigning healthcare delivery to advance universal healthcare coverage, enabling integration of healthcare services through organizational alignment to maintain care continuum, building the capacity of health workforce, developing effective treatment strategies through research based on local populations, integrating mental health into general public health policy and lastly, establishing reliable NCD surveillance and monitoring programs. Measures to address NCDs must be continued with focus on “health-in-all policies”, “whole-of-government” approach and “whole-of-society” approach.
Background: A major challenge in controlling the COVID-19 pandemic is the high false-negative rate of the commonly used standard RT-PCR methods for SARS-CoV-2 detection in clinical samples. Accurate detection is particularly challenging in samples with low viral loads that are below the limit of detection (LoD) of standard one- or two-step RT-PCR methods. Methods: We implement a three-step approach for SARS-CoV-2 detection and quantification that employs reverse transcription, targeted cDNA preamplification and nano-scale qPCR based on the Fluidigm 192.24 microfluidic chip. We validate the method using both positive controls and nasopharyngeal swab samples. Results: Using SARS-CoV-2 synthetic RNA and plasmid controls, we demonstrate that the addition of a preamplification step enhances the LoD of the Fluidigm method by 1,000-fold, enabling detection below 1 copy/μl. We applied this method to analyze 182 clinical NP swab samples previously diagnosed using a standard RT-qPCR protocol (91 positive, 91 negative) and demonstrate reproducible detection of SARS-CoV-2 over five orders of magnitude (< 1 to 106 viral copies/μl). Crucially, we detect SARS-CoV-2 with relatively low viral load estimates (<1 to 40 viral copies/μl) in 17 samples with negative clinical diagnosis, indicating a potential false negative rate of 18.7% by clinical diagnostic procedures. Conclusion: The three-step nano-scale RT-qPCR method can robustly detect SARS-CoV-2 in samples with relatively low viral loads (< 1 viral copy/μl) and has the potential to reduce the false negative rate of standard RT-PCR-based diagnostic tests for SARS-CoV-2 and other viral infections.
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