Since the emergence of the COVID-19 pandemic in December 2019 in Wuhan, China, there have been nearly 6,663,304 confirmed cases of COVID-19, including 392,802 deaths, worldwide as of 10:00 CEST 06 June 2020. In Africa, 152,442 COVID-19 cases and 4334 deaths have been reported as of 02 June 2020. The five countries with the highest commutative number of cases in Africa are South Africa, Egypt, Nigeria, Algeria, and Ghana. Africa, and the rest of world, has had to swiftly undertake the necessary measures to protect the continent from irreversible effects of the COVID-19 pandemic that is claiming lives and destroying livelihoods. The lower number of COVID-19 cases in most African countries is attributed to inadequate health systems, low-to-absent testing capacity, poor reporting systems, and insufficient numbers of medical staff. The COVID-19 pandemic poses a great threat to most African countries, from cities to rural areas, and has created a strong demand on already scarce resources. Intense mobilization of additional resources is required to implement established emergency contingency measures. Measures to prevent the spread of COVID-19 include closure of borders and restricting movement of people within a country; this has resulted in the tourism sector being adversely affected by the loss of income. Cooperative prevention and control measures are one of the promising solutions to deplete the spread of COVID-19 on the continent.

• Effect of sex hormones on COVID-19 outcome bias in males and females. • Effect of immunological factors on COVID-19 outcome bias in males and females. • Angiotensin-converting enzyme-2 (ACE2) system and COVID-19 outcome in males and females. • Correlation between smoking and COVID-19 incidence in males and females. • Possible therapeutic options for COVID-19.

Thymol, a natural monoterpene phenol is not only relevant clinically as an anti-microbial, anti-oxidant and anti-inflammatory agent but also holds the prospect as a natural template for pharmaceutical semi-synthesis of therapeutic agents. It is a major component of essential oils from many plants. Evidence abound linking overall bioactivity of thymol to its monoterpene nucleus, specifically, the hydroxyl (-OH) substituent on carbon number one (C1) on the monoterpene nucleus. Other studies have posited that the overall bioactivity of thymol is not substantially altered by chemical modification of - OH on the C1 of the monoterpene nucleus. In view of this, it is still unclear as to whether removal or modification of the -OH on C1 of the monoterpene nucleus relates generally or context-dependently to bioactivity of thymol. The present study investigated anti-bacterial effects of ester-and-ether substituted derivatives of thymol on S. aureus, P. aeruginosa and E. coli. twelve ester-and-ether substituted derivatives of thymol (6TM1s and 6TM2s) were synthesized and characterized by using HPLC, Mass spectrometry, and IR techniques. Anti-bacterial activity of the 12 thymol derivatives was evaluated using broth macrodilution and turbidimetric methods against pure clinical isolates (S. aureus, P. aeruginosa and E. coli). Standard anti-biotics used were Thymol Streptomycin and flucloxacillin, while DMSO was used as vehicle for thymol derivatives. MIC and MBC were determined. Thymol produced broad-spectrum growth inhibition on all isolates. At equimolar concentrations, thymol and reference drugs produced concentration-dependent growth inhibition against the isolates (Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli) compared to DMSO. Although the growth inhibitory effects of the ester-and-ether derivatives of thymol was significant (P ≤ 0.05) compared to DMSO, it was however insignificant (P ≥ 0.05) compared to thymol and reference antibiotics. Comparatively, at equimolar concentrations, ester-substituted derivatives of thymol, particularly the branched chain derivative (TM1C) produced more effective growth inhibition on the isolates than the ether-substituted derivatives of thymol. Thymol was twice as potent (MIC and MBC, 500 μg/ml) than both ester-and-ether substituted derivatives of thymol (MIC and MBC, > 1000 μg/ml) on all the three clinical isolates. Increase in side chain bulkiness of -OH moiety on the monoterpene nucleus of thymol decreased growth inhibition on isolates. Thymol has demonstrated broad-spectrum anti-bacterial effects attributable to the hydroxyl moiety on C1 of the monoterpene nucleus. Structural modification of the hydroxyl moiety on C1 of the monoterpene nucleus of thymol with either ether-or-ester substitutions yielded no significant anti-bacterial effects.

This study assessed the anti-inflammatory effect of thiamine (TA) in lipopolysaccharide-stimulated RAW264.7 cells and also assessed the preservative properties of TA in minced beef. TA demonstrated a concentration-dependent antimicrobial effect on microbial contaminants. Inhibition zones and MIC from the effect of TA on the tested bacterial strains were respectively within the ranges 15–20 mm and 62.5–700 µg/mL. TA significantly (p < 0.05) decreased all the pro-inflammatory factors [(nitric oxide (NO), prostaglandin E2 (PGE2), TNF-α, IL-6, IL-1β, and nuclear factor-κB (NF-κB)] monitored relative to LPS-stimulated RAW264.7 cells. TA inhibited the expression of both iNOS and COX-2. In minced beef flesh, the growth of Listeria monocytogenes was inhibited by TA. TA improved physicochemical and microbiological parameters of stored minced beef meat compared to control. Principal component analyses and heat maps elucidate the quality of the tested meats.