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1.
Global Pediatrics ; 4:100050, 2023.
Article in English | ScienceDirect | ID: covidwho-2328053

ABSTRACT

Introduction Management of possible severe bacterial infections in young infants (0–59 days) requires timely identification of danger signs and prompt administration of efficacious antibiotic treatment. The Possible Severe Bacterial Infection guidelines underscore the importance of close follow up in an outpatient basis to ensure treatment adherence and early detection of illness-related complications. The purpose of this study was to strengthen the follow up and referral of sick young infants on day 4 and 8 by introducing community-led interventions that facilitated community health volunteers to identify sick young infants, conduct community reviews, link data with responsive facilities, and refer appropriately. Methods Six health facilities were included in a longitudinal, descriptive, mixed methods approach weaved around an initial formative context assessment and three-monthly assessments between October 2019 to January 2020 with a endline assessment in August 2020. Quantitative data was extracted from facility registers to identify gaps in follow up and referral feasibility. Qualitative data was through focus group discussions with community health volunteers and key informant interviews with frontline providers. Results Qualitative data provided insights into key barriers and facilitators of community follow up and referral. Barriers include community socio-cultural practices, competing tasks, dysfunctional community referral pathway, drivers of common infections, and unavailability of essential commodities. Key facilitators entail indication of competency in identification of danger signs in sick young infants, presence of older women, men, and community resource persons that can leveraged on in community engagement and sensitization, and mothers are the primary decision makers in care seeking. There was increased utilization of decision support tools and an increase in the number of sick young infants managed in dispensaries. The COVID-19 pandemic however negatively impacted community follow up and referral of sick young infants. Conclusion Essential barriers and facilitators to follow up and community referral entwined with facility-based vulnerabilities were highlighted. A two-pronged intervention on improving communication, linkage and subsequent follow up of sick young infants was employed in the six participating facilities. The feasibility, adoption, and fidelity of strengthening community facility linkage through integrated communication strategies was documented, indicative of a successful community-facility linkage in dispensaries and health centers despite the effects of the COVID-19 pandemic.

2.
Diagnostics (Basel) ; 13(9)2023 May 07.
Article in English | MEDLINE | ID: covidwho-2318816

ABSTRACT

Globally, the emergence of the coronavirus disease (COVID-19) has had a significant impact on life. The need for ongoing SARS-CoV-2 screening employing inexpensive and quick diagnostic approaches is undeniable, given the ongoing pandemic and variations in vaccine administration in resource-constrained regions. This study presents results as proof of concept to use hybridization chain reaction (HCR) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a complex for detecting SARS-CoV-2. HCR hairpin probes were designed using the NUPACK web-based program and further used to amplify the SARS-CoV-2 N gene in archived nasopharyngeal samples. The results were visualized using agarose gels and CRISPR Cas12a-based lateral flow strips. The assay was evaluated using the gold standard, real-time polymerase chain reaction (RT-PCR), as recommended by the World Health Organization (WHO). The results show the comparative efficiency of HCR to RT-PCR. This study shows that HCR and CRISPR are viable alternatives for diagnosing SARS-CoV-2 in samples.

3.
Am J Trop Med Hyg ; 107(4): 845-849, 2022 10 12.
Article in English | MEDLINE | ID: covidwho-2265832

ABSTRACT

Early detection of SARS-CoV-2 infection is crucial to prevent its spread. This study aimed to document test sensitivity/specificity, correlation with cycle threshold value from polymerase chain reaction (PCR), fitness-for-use in different populations and settings, and user perspectives that could inform large-scale implementation. In this study, we evaluated the performance of a rapid antigen detection test, BD Veritor, and compared this (and another rapid test, Standard Q) against reverse transcription PCR (RT-PCR) in terms of sensitivity and specificity in 130 symptomatic and 130 asymptomatic adults. In addition, we evaluated the suitability and ease of use of the BD Veritor test in a subsample of study participants (n = 42) and implementers (n = 5). At 95% confidence interval, the sensitivity of the BD Veritor and Standard Q test were 70% and 63% in symptomatic and 87% and 73% in asymptomatic individuals, respectively, regarding positive SARS-CoV-2 RT-PCR results. Overall, the BD Veritor test was 78% sensitive and 99.5% specific compared with RT-PCR irrespective of the cycle threshold. This warrants large field evaluation as well as use of the rapid antigen test for quick assessment of SARS-CoV-2 for containment of epidemics in the country.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Antigens, Viral , Bangladesh/epidemiology , COVID-19/diagnosis , COVID-19 Testing , Humans , Sensitivity and Specificity
4.
Front Immunol ; 13: 955168, 2022.
Article in English | MEDLINE | ID: covidwho-2198858

ABSTRACT

More than two years after the start of COVID-19 pandemic, Africa still lags behind in terms vaccine distribution. This highlights the predicament of Africa in terms of vaccine development, deployment, and sustainability, not only for COVID-19, but for other major infectious diseases that plague the continent. This opinion discusses the challenges Africa faces in its race to vaccinate its people, and offers recommendations on the way forward. Specifically, to get out of the ongoing vaccine shortage trap, Africa needs to diversify investment not only to COVID-19 but also other diseases that burden the population. The continent needs to increase its capacity to acquire vaccines more equitably, improve access to technologies to enable local manufacture of vaccines, increase awareness on vaccines both in rural and urban areas to significantly reduce disease incidence of COVID-19 and as well as other prevalent diseases on the African continent such as HIV and TB. Such efforts will go a long way to reduce the disease burden in Africa.


Subject(s)
COVID-19 , Vaccines , Humans , Pandemics/prevention & control , Vaccinology , COVID-19/epidemiology , COVID-19/prevention & control , Africa/epidemiology
5.
Clin Lab Med ; 42(1): 31-56, 2022 03.
Article in English | MEDLINE | ID: covidwho-2130425

ABSTRACT

The coronavirus disease of 2019 (COVID-19) pandemic, caused by infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has undoubtedly resulted in significant morbidities, mortalities, and economic disruptions across the globe. Affordable and scalable tools to monitor the transmission dynamics of the SARS-CoV-2 virus and the longevity of induced antibodies will be paramount to monitor and control the pandemic as multiple waves continue to rage in many countries. Serologic assays detect humoral responses to the virus, to determine seroprevalence in target populations, or induction of antibodies at the individual level following either natural infection or vaccination. With multiple vaccines rolling out globally, serologic assays to detect anti-SARS-CoV-2 antibodies will be important tools to monitor the development of herd immunity. To address this need, serologic lateral flow assays (LFAs), which can be easily implemented for both population surveillance and home use, will be vital to monitor the evolution of the pandemic and inform containment measures. Such assays are particularly important for monitoring the transmission dynamics and durability of immunity generated by natural infections and vaccination, particularly in resource-limited settings. In this review, we discuss considerations for evaluating the accuracy of these LFAs, their suitability for different use cases, and implementation opportunities.


Subject(s)
COVID-19 , Antibodies, Viral , Humans , Pandemics , SARS-CoV-2 , Seroepidemiologic Studies
6.
Talanta Open ; 6: 100166, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2106030

ABSTRACT

In response to the ongoing coronavirus disease 2019 (COVID-19) pandemic and disparities of vaccination coverage in low-and middle-income countries, it is vital to adopt a widespread testing and screening programme, combined with contact tracing, to monitor and effectively control the infection dispersion in areas where medical resources are limited. This work presents a lab-on-a-chip device, namely 'IFAST-LAMP-CRISPR', as an affordable, rapid and high-precision molecular diagnostic means for detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The herein proposed 'sample-to-answer' platform integrates RNA extraction, amplification and molecular detection with lateral flow readout in one device. The microscale dimensions of the device containing immiscible liquids, coupled with the use of silica paramagnetic beads and guanidine hydrochloride, streamline sample preparation (including RNA extraction, concentration and purification) in 15 min with minimal hands-on steps. The pre-amplification in combination with CRISPR-Cas12a detection assays targeting the nucleoprotein (N) gene achieved visual identification of ≥ 470 copies mL-1 genomic SARS-CoV-2 samples in 45 min. On-chip assays showed the ability to isolate and detect SARS-CoV-2 RNA from 100 genome copies mL-1 of replication-deficient viral particles in 1 h. This simple, affordable and integrated platform demonstrated a visual, faster, and yet specificity- and sensitivity-comparable alternative to the costly gold-standard reverse transcription-polymerase chain reaction (RT-PCR) assay, requiring only a simple heating source. Initial testing illustrates the platform viability both on nasopharyngeal swab and saliva samples collected using the easily accessible Swan-brand cigarette filter, providing a complete workflow for COVID-19 diagnostics in low-resource settings.

7.
BMC Genomics ; 23(1): 627, 2022 Sep 01.
Article in English | MEDLINE | ID: covidwho-2009353

ABSTRACT

Genomic surveillance and identification of COVID-19 outbreaks are important in understanding the genetic diversity, phylogeny, and lineages of SARS-CoV-2. Genomic surveillance provides insights into circulating infections, and the robustness and design of vaccines and other infection control approaches. We sequenced 57 SARS-CoV-2 isolates from a Kenyan clinical population, of which 55 passed quality checks using the Ultrafast Sample placement on the Existing tRee (UShER) workflow. Phylo-genome-temporal analyses across two regions in Kenya (Nairobi and Kiambu County) revealed that B.1.1.7 (Alpha; n = 32, 56.1%) and B.1 (n = 9, 15.8%) were the predominant lineages, exhibiting low Ct values (5-31) suggesting high infectivity, and variant mutations across the two regions. Lineages B.1.617.2, B.1.1, A.23.1, A.2.5.1, B.1.596, A, and B.1.405 were also detected across sampling sites within target populations. The lineages and genetic isolates were traced back to China (A), Costa Rica (A.2.5.1), Europe (B.1, B.1.1, A.23.1), the USA (B.1.405, B.1.596), South Africa (B.1.617.2), and the United Kingdom (B.1.1.7), indicating multiple introduction events. This study represents one of the genomic SARS-CoV-2 epidemiology studies in the Nairobi metropolitan area, and describes the importance of continued surveillance for pandemic control.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , Genome, Viral , Genomics , Humans , Kenya/epidemiology , Phylogeny , SARS-CoV-2/genetics
8.
DNA Cell Biol ; 41(1): 30-33, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1864942

ABSTRACT

With the coronavirus disease of 2019 (COVID-19) becoming a full-blown outbreak in Africa, coupled with many other challenges faced on the African continent, it is apparent that Africa continues to need diagnostics to enable case identification and recovery to this and future challenges. With the slow vaccination rates across the continent, reliable diagnostic tests will be in demand, likely for years to come. Thus, access to reliable diagnostic tools to detect the severe acute respiratory syndrome of the coronavirus-2 (SARS-CoV-2), the virus responsible for COVID-19, remain a critical pillar to monitor and contain new waves of COVID-19. Increasing the local capacity to manufacture and roll-out vaccines and decentralized COVID-19 testing are paramount for fighting the pandemic in Africa.


Subject(s)
COVID-19 Testing , Humans
9.
Anal Chim Acta ; 1177: 338758, 2021 Sep 08.
Article in English | MEDLINE | ID: covidwho-1267550

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the unprecedented global pandemic of coronavirus disease-2019 (COVID-19). Efforts are needed to develop rapid and accurate diagnostic tools for extensive testing, allowing for effective containment of the infection via timely identification and isolation of SARS-CoV-2 carriers. Current gold standard nucleic acid tests require many separate steps that need trained personnel to operate specialist instrumentation in laboratory environments, hampering turnaround time and test accessibility, especially in low-resource settings. We devised an integrated on-chip platform coupling RNA extraction based on immiscible filtration assisted by surface tension (IFAST), with RNA amplification and detection via colorimetric reverse-transcription loop mediated isothermal amplification (RT-LAMP), using two sets of primers targeting open reading frame 1a (ORF1a) and nucleoprotein (N) genes of SARS-CoV-2. Results were identified visually, with a colour change from pink to yellow indicating positive amplification, and further confirmed by DNA gel electrophoresis. The specificity of the assay was tested against HCoV-OC43 and H1N1 RNAs. The assay based on use of gene N primers was 100% specific to SARS-CoV-2 with no cross-reactivity to HCoV-OC43 nor H1N1. Proof-of-concept studies on water and artificial sputum containing genomic SARS-CoV-2 RNA showed our IFAST RT-LAMP device to be capable of extracting and detecting 470 SARS-CoV-2 copies mL-1 within 1 h (from sample-in to answer-out). IFAST RT-LAMP is a simple-to-use, integrated, rapid and accurate COVID-19 diagnostic platform, which could provide an attractive means for extensive screening of SARS-CoV-2 infections at point-of-care, especially in resource-constrained settings.


Subject(s)
COVID-19 , Lab-On-A-Chip Devices , RNA, Viral , COVID-19/diagnosis , Humans , Influenza A Virus, H1N1 Subtype , Molecular Diagnostic Techniques , Nucleic Acid Amplification Techniques , RNA, Viral/isolation & purification , SARS-CoV-2 , Sensitivity and Specificity
10.
AAS Open Res ; 3: 4, 2020.
Article in English | MEDLINE | ID: covidwho-268570

ABSTRACT

Since its emergence in Wuhan, China in December 2019, novel Coronavirus disease - 2019 (COVID-19) has rapidly spread worldwide, achieving pandemic status on 11 th March, 2020. As of 1 st April 2020, COVID-19, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), had infected over 800,000 people and caused over 40,000 deaths in 205 countries and territories. COVID-19 has had its heaviest toll on Europe, United States and China. As of 1 st of April 2020, the number of confirmed COVID-19 cases in Africa was relatively low, with the highest number registered by South Africa, which had reported 1,380 confirmed cases. On the same date (also the date of this review), Africa had reported 5,999 confirmed cases, of which 3,838 (almost 65%) occurred in South Africa, Algeria, Egypt, Morocco and Tunisia, with the remaining 2,071 cases distributed unevenly across the other African countries. We speculate that while African nations are currently experiencing much lower rates of COVID-19 relative to other continents, their significantly lower testing rates may grossly underestimate incidence rates. Failure to grasp the true picture may mean crucial windows of opportunity shut unutilized, while limited resources are not deployed to maximum effect. In the absence of extensive testing data, an overestimation of spread may lead to disproportionate measures being taken, causing avoidable strain on livelihoods and economies. Here, based on the African situation, we discuss COVID-19 diagnostic challenges and how they may blunt responses.

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