Combining Rapid Antigen Testing and Syndromic Surveillance Improves Community-Based COVID-19 Detection in Low-to-Middle-Income Countries

Diagnostics for COVID-19 detection are limited in many settings. Syndromic surveillance is often the only means to identify cases, but lacks specificity. Rapid antigen testing is inexpensive and easy-to-deploy but concerns remain about sensitivity. We examine how combining these approaches can improve surveillance for guiding interventions in low-income communities in Dhaka, Bangladesh. Rapid-antigen-tests and PCR validation was performed on 1172 symptomatically-identified individuals at home. Statistical models were fit to predict PCR status using rapid-antigen-test results, syndromic data, and their combination. Model predictive and classification performance was examined under contrasting epidemiological scenarios to evaluate their potential for improving diagnoses. Models combining rapid-antigen-test and syndromic data yielded equal-to-better performance to rapid-antigen-test-only models across all scenarios. These results show that drawing on complementary strengths across two rapid diagnostics, improves COVID-19 detection, and reduces false-positive and -negative diagnoses to match local requirements; improvements achievable without additional expense, or changes for patients or practitioners.

Tuberculous Meningitis in Children: Reducing the Burden of Death and Disability

Tuberculous meningitis disproportionately affects young children. As the most devastating form of tuberculosis, it is associated with unacceptably high rates of mortality and morbidity even if treated. Challenging to diagnose and treat, tuberculous meningitis commonly causes long-term neurodisability in those who do survive. There remains an urgent need for strengthened surveillance, improved rapid diagnostics technology, optimised anti-tuberculosis drug therapy, investigation of new host-directed therapy, and further research on long-term functional and neurodevelopmental outcomes to allow targeted intervention. This review focuses on the neglected field of paediatric tuberculous meningitis and bridges current clinical gaps with research questions to improve outcomes from this crippling disease.

Viral Haemorrhagic Fevers and Malaria Co-Infections Among Febrile Patients Seeking Health Care in Tanzania

Background: In recent years there have been reports of viral haemorrhagic fever (VHF) epidemics in Sub-Saharan Africa where malaria is endemic. VHF and malaria have overlapping clinical presentations making differential diagnosis a challenge. The objective of this study was to determine the prevalence of selected zoonotic VHFs and malaria co-infections among febrile patients seeking health care in Tanzania. Methods: This facility-based cross-section study was carried out in Buhigwe, Kalambo, Kyela, Kilindi, Kinondoni, Kondoa, Mvomero, and Ukerewe districts in Tanzania. The study involved febrile patients seeking health care from primary healthcare facilities. Blood samples were collected and tested for infections due to malaria, Crimean-Congo haemorrhagic fever (CCHF), Ebola virus disease (EVD), Marburg virus disease (MVD), Rift Valley fever (RVF) and yellow fever (YF). Malaria infections were tested using rapid diagnostics tests while exposure to VHFs was determined by screening for immunoglobulin M antibodies using commercial enzyme-linked immunosorbent assays. Results: A total of 308 participants (mean age=35±18.9 years) were involved in the study. Of these, 54 (17.5%) had malaria infection and 15 (4.8%) were positive for IgM antibodies against VHFs (RVF=8; CCHF=2; EBV=3; MBV=1; YF=1). Six (1.9%) individuals had both VHF (RVF=2; CCHF=1; EVD=2; MVD=1) and malaria infections. The highest co-infection prevalence (0.6%), was observed among individuals aged 46-60 years (p<0.05). District was significantly associated with co-infection (p<0.05) with the highest prevalence recorded in Buhigwe (1.2%) followed by Kinondoni (0.9%) districts. Headache (100%) and muscle, bone, back and joint pains (83.3%) were the most significant complaints among those infected with both VHFs and malaria (p=0.001). Conclusions: Co-infections of VHF and malaria are prevalent in Tanzania and affect more the older than the younger population. Since the overlapping symptoms in co-infected individuals may challenge accurate diagnosis, adequate laboratory diagnosis should be emphasized in the management of febrile illnesses.

Comparison of Antigen Tests and qPCR in Rapid Diagnostics of Infections Caused by SARS-CoV-2 Virus

Diagnostics of the coronavirus disease 2019 (COVID-19) using molecular techniques from the collected respiratory swab specimens requires well-equipped laboratory and qualified personnel, also it needs several hours of waiting for results and is expensive. Antigen tests appear to be faster and cheaper but their sensitivity and specificity are debatable. The aim of this study was to compare a selected antigen test with quantitative polymerase chain reaction (qPCR) tests results. Nasopharyngeal swabs were collected from 192 patients with COVID-19 symptoms. All samples were tested using Vitassay qPCR SARS-CoV-2 kit and the Humasis COVID-19 Ag Test (MedSun) antigen immunochromatographic test simultaneously. Ultimately, 189 samples were tested; 3 samples were excluded due to errors in taking swabs. The qPCR and antigen test results were as follows: 47 positive and 142 negative, and 45 positive and 144 negative, respectively. Calculated sensitivity of 91.5% and specificity of 98.6% for the antigen test shows differences which are not statistically significant in comparison to qPCR. Our study showed that effectiveness of the antigen tests in rapid laboratory diagnostics is high enough to be an alternative and support for nucleic acid amplification tests (NAAT) in the virus replication phase in the course of COVID-19.

A Case-Control Study for the Effectiveness of Oral Zinc in the Prevention and Mitigation of COVID-19

Background: The ongoing coronavirus disease-19 (COVID-19) pandemic (caused by an infection with severe acute respiratory syndrome (SARS)-coronavirus (CoV-2) has put a burden on the medical community and society at large. Efforts to reduce the disease burden and mortality over the course of the pandemic have focused on research to rapidly determine age-stratified seroepidemiologic surveys, a centralized research program to fast-track the most promising rapid diagnostics and serologic assays, and the testing of potential anti-viral agents, immunologic therapies, and vaccine candidates. Despite the lack of official recognition for the role of nutrition in the fight against COVID-19 infection, multiple groups proposed zinc supplementation as an adjuvant for the management of participants.Method: In an ambulatory, interventional, prospective, single-blind study, we evaluated the effectiveness of zinc supplementation in the prevention and mitigation of COVID-19 in two similar participant groups. In Clinic A (n = 104) participants were randomized to receive 10 mg, 25 mg, or 50 mg zinc picolinate daily, and Clinic B control participants paired according to their demographics and clinical parameters (n = 96). All participants were compared based on demographics, clinical comorbidities, blood counts, renal functions, vitamin D levels, and their development of symptomatic COVID-19 infection.Results: Symptomatic COVID-19 infection was significantly higher among the control group participants (N = 9, 10.4%) than the treatment participants (N = 2, 1.9%), p = 0.015. The unadjusted odds ratio indicates that symptomatic COVID-19 infection was 5.93 [95% CI: 1.51, 39.26] higher in the control group, p &lt; 0.01. Controlling for co-morbidities, individuals in the control group were 7.38 (95% CI: 1.80, 50.28) times more likely to develop symptomatic COVID-19 infection as compared with individuals in the treatment group (p &lt; 0.01). For every-one unit increase in the number of co-morbidities, the likelihood of developing symptomatic COVID-19 infection increased 1.57 (95% CI: 1.16, 2.19) (p = 0.01).Discussion: The findings from our study suggest that zinc supplementation in all three doses (10, 25, and 50 mg) may be an effective prophylaxis of symptomatic COVID-19 and may mitigate the severity of COVID-19 infection.Conclusion: Zinc is a relatively inexpensive mineral nutrient that is an effective prophylactic agent to prevent and mitigate the potentially deadly symptomatic SARS-CoV-2 infection. As the COVID-19 pandemic continues with a lag in vaccinations in some regions and the continued emergence of dangerously infectious variants of SARS-CoV-2, it is important to replicate our data in other populations and locations and to engage public health and nutrition services on the emergent need to use zinc supplantation or fortification of staple foods in the prevention and mitigation of COVID-19 infection severity.

Features of rapid diagnostics in the process of decompression measures

The article reveals the primary social and psychological rehabilitation (decompression) at the stage of the march of the unit from the area of environmental protection, both permanent locations and permanent locations. The commander's account of certain information when deciding on decompression in a certain unit is shown. The drawing up of an individual plan of a serviceman in the process of decompression is shown, as well as the stages preceding this rehabilitation.

Performance Validation of COVID-19 Self-Conduct Buccal and Nasal Swabs RTK-Antigen Diagnostic Kit

The antigen rapid diagnostic test (Ag-RDT) is an immunodiagnostic test that detects the presence of viral proteins (antigens) expressed by the COVID-19 virus in a sample from a patient’s respiratory tract. This study focused on evaluating the performance of self-conduct buccal and nasal swabs RTK-antigen test compared to nasopharyngeal swab RTK-based COVID-19 diagnostic assays, Panbio™ COVID-19 Ag Rapid Test Device (Nasopharyngeal) (Abbott Rapid Diagnostics Jena GmbH, Jena, Germany) used in hospitals for first-line screening. The sensitivity and specificity of the paired RTK-Ag test in detecting the an-tigen were calculated at 96.4% and 100%, respectively. Fisher exact tests showed the association between nasopharyngeal swabs RTK-Ag assay and buccal-nasal swabs RTK-Ag from ProdetectTM is significant (p-values < 0.001). The result showed that a self-conducted buccal and nasal RTK-antigen rapid test by the patients is comparable to the results obtained from a rapid test device conducted by trained medical personnel using a nasopharyngeal swab.

Cell-morphodynamic phenotype classification with application to cancer metastasis using cell magnetorotation and machine-learning

We define cell morphodynamics as the cell’s time dependent morphology. It could be called the cell’s shape shifting ability. To measure it we use a biomarker free, dynamic histology method, which is based on multiplexed Cell Magneto-Rotation and Machine Learning. We note that standard studies looking at cells immobilized on microscope slides cannot reveal their shape shifting, no more than pinned butterfly collections can reveal their flight patterns. Using cell magnetorotation, with the aid of cell embedded magnetic nanoparticles, our method allows each cell to move freely in 3 dimensions, with a rapid following of cell deformations in all 3-dimensions, so as to identify and classify a cell by its dynamic morphology. Using object recognition and machine learning algorithms, we continuously measure the real-time shape dynamics of each cell, where from we successfully resolve the inherent broad heterogeneity of the morphological phenotypes found in a given cancer cell population. In three illustrative experiments we have achieved clustering, differentiation, and identification of cells from (A) two distinct cell lines, (B) cells having gone through the epithelial-to-mesenchymal transition, and (C) cells differing only by their motility. This microfluidic method may enable a fast screening and identification of invasive cells, e.g., metastatic cancer cells, even in the absence of biomarkers, thus providing a rapid diagnostics and assessment protocol for effective personalized cancer therapy.

A SARS-CoV-2 coronavirus nucleocapsid protein antigen-detecting lateral flow assay

Inexpensive, simple, rapid diagnostics are necessary for efficient detection, treatment, and mitigation of COVID-19. Assays for SARS-CoV2 using reverse transcription polymerase chain reaction (RT-PCR) offer good sensitivity and excellent specificity, but are expensive, slowed by transport to centralized testing laboratories, and often unavailable. Antigen-based assays are inexpensive and can be rapidly mass-produced and deployed at point-of-care, with lateral flow assays (LFAs) being the most common format. While various manufacturers have produced commercially available SARS-Cov2 antigen LFAs, access to validated tests remains difficult or cost prohibitive in low-and middle-income countries. Herein, we present a visually read open-access LFA (OA-LFA) using commercially-available antibodies and materials for the detection of SARS-CoV-2. The LFA yielded a Limit of Detection (LOD) of 4 TCID50/swab of gamma irradiated SARS-CoV-2 virus, meeting the acceptable analytical sensitivity outlined by in World Health Organization target product profile. The open-source architecture presented in this manuscript provides a template for manufacturers around the globe to rapidly design a SARS-CoV2 antigen test.