Arbovirus and its potential to lead the next global pandemic from sub-Saharan Africa: What lessons have we learned from COVID-19?

Risk and predisposing factors for viral zoonoses abound in the sub-Saharan Africa (SSA) region with significant public health implications. For several decades, there have been several reports on the emergence and re-emergence of arbovirus infections. The lifetime burden of arboviral diseases in developing countries is still poorly understood. Studies indicate significant healthcare disruptions and economic losses attributed to the viruses in resource-poor communities marked by impairment in the performance of daily activities. Arboviruses have reportedly evolved survival strategies to aid their proliferation in favorable niches, further magnifying their public health relevance. However, there is poor knowledge about the viruses in the region. Thus, this review presents a survey of zoonotic arboviruses in SSA, the burden associated with their diseases, management of diseases as well as their prevention and control, mobility and determinants of infections, their vectors, and co-infection with various microorganisms. Lessons learned from the ongoing coronavirus disease 2019 (COVID-19) pandemic coupled with routine surveillance of zoonotic hosts for these viruses will improve our understanding of their evolution, their potential to cause a pandemic, control and prevention measures, and vaccine development.

Circulation of hepatitis B virus genotype-E among outpatients in tertiary hospitals in the Niger-Delta region of Nigeria

Introduction

Hepatitis B virus (HBV) infection continues to be a significant public health challenge globally, with higher disease burden in developing countries. HBV genotypes are associated with different geographical regions and clinical outcomes. Limited information exists on epidemiology of HBV in the Niger-Delta region (South-South) of Nigeria. Consequently, this study was designed to characterise hepatitis B virus infection among outpatients in selected tertiary hospitals in the region.

Methodology

Between June and August 2017, consenting nine hundred asymptomatic out-patients were enrolled and initially screened for HBV infection using one step Hepatitis B surface antigen (HBsAg) strip and subsequently re-tested using HBsAg and Hepatitis B core total antibody (anti-HBc) specific Enzyme-Linked Immunosorbent Assay (ELISA). Blood serum with detectable HBsAg were subsequently subjected to DNA extraction, S-gene amplification using a nested polymerase chain reaction (PCR) protocol, gel electrophoresis, sequencing and phylogenetic analysis.

Results

Seroprevalence of HBsAg was 4.6% (95% CI 2.5–7.1) and anti-HBc was 10.1% (95% confidence interval (CI) 6.1–15.3). Of the 41 HBsAg positive samples subjected to DNA extraction and HBV S-gene specific PCR, only 6 (14.6%) yielded the expected ∼408bp band. Phylogenetic analysis based on HBV pre-S/S sequences identified all six typable samples as genotype E, subtype ayw4 of the West African clade.

Conclusion

Results of the study confirm the presence and circulation of HBV genotype-E in the Niger-Delta region of Nigeria, thus corroborating the inclusion of the country in the Genotype E crescent. The authors advocate value-added HBV intervention in the region and the country at large.

Systematic exo-endo encapsulation of hydroxyurea (HU) by Cu, Ag, and Au-doped gallium nitride nanotubes (GaNNT) for smart therapeutic delivery

Similar to the more well-known carbon nanotubes, gallium nitride nanotubes (GaNNT) are among the materials that scientists have found to be extremely helpful in transporting drugs and to provide significant potential for multi-modal medical therapies. Here, the potential of Cu, Ag, and Au-doped GaNNT for smart delivery of the anticancer medication hydroxyurea (HU) was extensively investigated employing quantum chemical analysis and density functional theory (DFT) computation at the B3LYP-GD3BJ/def2-SVP level of theory. The systematic approach used in this study entails examining the exo (outside)-and endo (inside) loading of HU utilizing the investigated nanotubes in order to understand the adsorption, sensing processes, bonding types, and thermodynamic properties. Results of the HOMO-LUMO studies show that metal-doped GaNNTs with the hydroxyurea (HU) at the endo - interaction of the drug of the nanotube produced more reduced energy gaps (0.911-2.039 eV) compared with metal-doped GaNNTs complexes at the outside - interaction of the drug on the nanotube (2.25-3.22 eV) and as such reveal their suitability for use as drug delivery materials. As observed in the endo-interaction of HU adsorptions in the tubes, HU_endo_Au@GaNNT possessed the highest adsorption energy values of -118.716 kcal/mol which shows the most chemisorption between the surfaces and the adsorbate while for HU_exo_Ag@GaNNT is -97.431 kcal/mol for the highest exo-interactions. These results suggest that HU drug interacted inside the Ag, Au, and Cu doped GaNNT will be very proficient as a carrier of the HU drug into bio systems. These results are along with visual studies of weak interactions, thermodynamics, sensor, and drug release mechanisms suggest strongly the endo-encapsulation of HU as the best mode for smart drug delivery.