Investment in SARS-CoV-2 sequencing in Africa over the past year has led to a major increase in the number of sequences generated, now exceeding 100,000 genomes, used to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence domestically, and highlight that local sequencing enables faster turnaround time and more regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and shed light on the distinct dispersal dynamics of Variants of Concern, particularly Alpha, Beta, Delta, and Omicron, on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve, while the continent faces many emerging and re-emerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century.

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A comprehensive theoretical conformational analysis of the anti-HIV Nikavir prodrug was carried out; this prodrug has noticeable advantage over the approved drug AZT. The whole conformational parameters (χ, α, β, γ, δ, ϕ, P and νmax) were analysed as well as the NBO natural atomic charges. The calculations were carried out by means of DFT/B3LYP and ab initio MP2 methods with full relaxation of all geometrical parameters. The search located at least 67 stable structures, 4 of which were within a 1 kcal/mol electronic energy range of the global minimum. By MP2 it corresponds to the calculated values of the exocyclic torsional angles χ=-108.0°, β=14.5°, γ=76.7° and ε=71.5°. The results obtained are in accordance to those found in related anti-HIV nucleoside analogues. Comparisons of the conformers with those determined in the common anti-HIV drug AZT were carried out. A detailed analysis of the lowest vibrations (<200 cm(-1)) in the best conformer of Nikavir was carried out. The most stable hydrated cluster of this conformer with 20 explicit water molecules was determined. Calculations in five of its 6'-derivatives were performed to identify structural trends that might correlate with the anti-HIV activity of these compounds. Ten structure-activity relationships/tendencies were established that can help for the design of new drugs. Several recommendations for this design were expressed.

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