Development of an Affordable ELISA Targeting the SARS-CoV-2 Nucleocapsid and Its Application to Samples from the Ongoing COVID-19 Epidemic in Ghana.

INTRODUCTION: The true nature of the population spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in populations is often not fully known as most cases, particularly in Africa, are asymptomatic. Finding the true magnitude of SARS-CoV-2 spread is crucial to provide actionable data about the epidemiological progress of the disease for researchers and policymakers. This study developed and optimized an antibody enzyme-linked immunosorbent assay (ELISA) using recombinant nucleocapsid antigen expressed in-house using a simple bacterial expression system. METHODS: Nucleocapsid protein from SARS-CoV-2 was expressed and purified from Escherichia coli. Plasma samples used for the assay development were obtained from Ghanaian SARS-CoV-2 seropositive individuals during the pandemic, while seronegative controls were plasma samples collected from blood donors before the coronavirus disease 2019 (COVID-19) pandemic. Another set of seronegative controls was collected during the COVID-19 pandemic. Antibody detection and levels within the samples were validated using commercial kits and Luminex. Analyses were performed using GraphPad Prism, and the sensitivity, specificity and background cut-off were calculated. RESULTS AND DISCUSSION: This low-cost ELISA (£0.96/test) assay has a high prediction of 98.9%, and sensitivity and specificity of 97% and 99%, respectively. The assay was subsequently used to screen plasma from SARS-CoV-2 RT-PCR-positive Ghanaians. The assay showed no significant difference in nucleocapsid antibody levels between symptomatic and asymptomatic, with an increase of the levels over time. This is in line with our previous publication. CONCLUSION: This study developed a low-cost and transferable assay that enables highly sensitive and specific detection of human anti-SARS-CoV-2 IgG antibodies. This assay can be modified to include additional antigens and used for continuous monitoring of sero-exposure to SARS-CoV-2 in West Africa.

The COVID-19, tuberculosis and HIV/AIDS: Ménage à Trois.

In December 2019, a novel pneumonic condition, Coronavirus disease 2019 (COVID- 19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), broke out in China and spread globally. The presentation of COVID-19 is more severe in persons with underlying medical conditions such as Tuberculosis (TB), Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) and other pneumonic conditions. All three diseases are of global concern and can significantly affect the lungs with characteristic cytokine storm, immunosuppression, and respiratory failure. Co-infections of SARS-CoV-2 with HIV and Mycobacterium tuberculosis (Mtb) have been reported, which may influence their pathogenesis and disease progression. Pulmonary TB and HIV/AIDS patients could be more susceptible to SARS-CoV-2 infection leading to lethal synergy and disease severity. Therefore, the biological and epidemiological interactions of COVID-19, HIV/AIDS, and TB need to be understood holistically. While data is needed to predict the impact of the COVID-19 pandemic on these existing diseases, it is necessary to review the implications of the evolving COVID-19 management on HIV/AIDS and TB control, including therapy and funding. Also, the impact of long COVID on patients, who may have this co-infection. Thus, this review highlights the implications of COVID-19, HIV/AIDS, and TB co-infection compares disease mechanisms, addresses growing concerns, and suggests a direction for improved diagnosis and general management.

Knowledge, attitude and perception of West Africans towards COVID-19: a survey to inform public health intervention.

BACKGROUND: The first case of the novel coronavirus disease-2019 (COVID-19) in West Africa was first confirmed in Nigeria in February 2020. Since then, several public health interventions and preventive measures have been implemented to curtail transmission of the causative agent, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Therefore, this study was performed to assess the knowledge, attitudes, and perceptions of West Africans towards COVID-19. METHODS: An online survey was conducted between 29 September to 29 October 2020 among West Africans. Thirty-three survey questions were designed to collect sociodemographic data and participants' knowledge, attitude and perception towards COVID-19. The study targeted all West African nationals who were 18 years and above, and willing to participate in the study. Participants were either in-country or abroad. RESULTS: Overall, 1106 respondents (≥18 years) from 16 West African countries, with about 12.1% of them residing outside the West African subregion, participated in the survey. The respondents had an average COVID-19 knowledge score of 67.82 ± 8.31, with knowledge of the disease significantly associated with the country of residence (p = 0.00) and marginally (p = 0.05) so with settlement types (i.e., urban, suburban and rural areas). Most respondents (93.4%) could identify the main COVID-19 symptoms, and 73.20% would consult a healthcare professional if infected with SARS-CoV-2. Also, 75.2% of the respondents are willing to receive the COVID-19 vaccine, whereas 10.40% and 14.40% are unwilling and undecided, respectively. Perceptions of what constitute COVID-19 preventive measures were highly variable. Approximately, 8% of the respondents felt that their government responded excellently in managing the pandemic while a third felt that the response was just good. Also, more than half (54%) opined that isolation and treatment of COVID-19 patients is a way of curbing SARS-CoV-2 spread. CONCLUSIONS: Most West Africans have basic knowledge of COVID-19 and showed a positive attitude, with likely proactive practice towards the disease. However, results showed that these varied across countries and are influenced by the types of settlements. Therefore, the health and education authorities in various countries should develop focused measures capturing people in different settlements to improve their preventative measures when designing public health interventions for COVID-19 and any future epidemics or pandemics.

Breast cancer in sub-Saharan Africa: The current state and uncertain future.

Breast cancer is the commonest cause of global cancer-related deaths in women and a public health burden in sub-Saharan Africa (SSA). Although the disease incidence in SSA seems lower, mortality rates are disproportionately high in comparison to high-income countries. The global disease burden is growing, with SSA reporting the majority of cases; however, the dearth of information results in insufficient data which is barely representative of the actual disease burden in this population. Future incidence predictions assign the subregion with a majority of the cases and associated deaths. Breast cancer presents with racial and ethnic variations, and available evidence suggests geographical diversity and persistent risk factors that have barely been explored in SSA. Breast cancer is a complex genetic disease, but the genetic risk factors in the extant African population, which is the most genetically diverse population, is scant and of low quality. This review focuses on the burden, prevalence, detection, treatment, survival, biology, as well as risk factors, and reinforces the need for breast cancer-associated risk factor investigation and population-specific studies in SSA.

In Vitro Assessment of Antiplasmodial Activity and Cytotoxicity of Polyalthia longifolia Leaf Extracts on Plasmodium falciparum Strain NF54.

BACKGROUND: Malaria is one of the most important life-threatening infectious diseases in the tropics. In spite of the effectiveness of artemisinin-based combination therapy, reports on reduced sensitivity of the parasite to artemisinin in Cambodia and Thailand warrants screening for new potential antimalarial drugs for future use. Ghanaian herbalists claim that Polyalthia longifolia has antimalarial activity. Therefore, antiplasmodial activity, cytotoxic effects, and antioxidant and phytochemical properties of P. longifolia leaf extract were investigated in this study. METHODOLOGY/PRINCIPAL FINDINGS: Aqueous, 70% hydroethanolic and ethyl acetate leaf extracts were prepared using standard procedures. Antiplasmodial activity was assessed in vitro by using chloroquine-sensitive malaria parasite strain NF54. The SYBR® Green and tetrazolium-based calorimetric assays were used to measure parasite growth inhibition and cytotoxicity, respectively, after extract treatment. Total antioxidant activity was evaluated using a free radical scavenging assay. Results obtained showed that extracts protected red blood cells against Plasmodium falciparum mediated damage. Fifty percent inhibitory concentration (IC50) values were 24.0±1.08 µg/ml, 22.5±0.12 µg/ml, and 9.5±0.69 µg/ml for aqueous, hydroethanolic, and ethyl acetate extracts, respectively. Flavonoids, tannins, and saponins were present in the hydroethanolic extract, whereas only the latter was observed in the aqueous extract. Aqueous and hydroethanolic extracts showed stronger antioxidant activities compared to the ethyl acetate extract. CONCLUSIONS/SIGNIFICANCE: The extracts of P. longifolia have antiplasmodial properties and low toxicities to human red blood cells. The extracts could be developed as useful alternatives to antimalarial drugs. These results support claims of the herbalists that decoctions of P. longifolia are useful antimalarial agents.