Evolution of SARS-CoV-2 variants: a mini-review

SARS-CoV-2 has evolved over time with several mutations, especially on the spike protein, which has led to emergence of various variants. With the evolution of SARS-CoV-2 come new challenges in surveillance, effectiveness of preventive and treatment strategies, and outcome of the disease. Despite the lockdowns, mask mandates and other preventive measures put in place, in addition to over 10 million vaccine doses that have been administered globally as of February 2022, COVID-19 cases have risen to over 435 million and resulted in over 5.9 million deaths, largely as a result of the evolution of SARS-CoV-2 variants. To review the evolution of these variants, we searched different online database sources using keywords such as "source of SARS-CoV-2", "SARS-CoV-2 origin", "evolution of SARS-CoV-2", "SARS-CoV-2 variants", "variants of concern", "variants of interest", and "variants of high consequence". This was to enable us give a good report about the various variants of SARS-CoV-2 that have emerged so far, and the public health challenges posed by them.

Kristen Rat Sarcoma Viral Oncogene Mutations in Colorectal Carcinomas at the University Teaching Hospital in Lusaka, Zambia

ackground: The second leading cause of cancerrelated deaths worldwide iscolorectal cancer. With an incidence rate of 4.8 per 100,000, this is Zambia's sixth most prevalent cancer; Methods: This laboratory-based, cross-sectional study examined the frequency of Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation and its association with prognostic factors in colorectal carcinoma cases from the University Teaching Hospital-Adult Hospital (UTHs), Lusaka, Zambia; Results: Thirty (30) formalin-fixed paraffinembedded (FFPE) samples collected between June 2017 and June 2018 were sent to the Lancet laboratories and analyzed for KRAS mutations (codons 12 and 13). One FFPE block did not meet the inclusion criteria and was excluded. The demographic and clinicopathological data were analyzed using STATA 12. Males outnumber females by 20 to nine. The average age of the patient was 45 ± 16 years. The rectum was the location of 44.8% of the tumors, with the majority being conventional adenocarcinoma (CAC) (65.6 %). All cases (100%) had advanced-stage (stages 3 and 4) disease;however, only 27.6% of patient tumors exhibited lymphovascular invasion. KRAS mutation was detected in 11 (37.9%) cases and mainly in left-sided tumors (62.5%). KRAS mutations were only detected in CAC and serrated adenocarcinoma subtypes. No significant associations were observed between the KRAS mutation status and tumor or patient's clinical and sociodemographic factors; Conclusion: We advocate for incorporating KRAS mutation testing into the standard of care for treating colorectal cancer.

Recent Change of locality as Risk Factor for Malaria Fever among New Residents of Ahoada East Local Government Area in Southern Nigeria

Relocation which is a well-known determinant of malaria in non-immune travelers to malarious areas; has also been found to be a risk factor for malaria among semi-immune persons who change locality within endemic regions. Further research evidence suggests that the higher transmission intensity at the travel location is an underlying factor which may indicate exposure to new variants of P falciparum for which specific immunity is lacking. This study was conducted to determine if recent change of locality increased the risk of malaria fever among semi-immune National Youth Service Corps members serving in a district in southern Nigeria.Method: Ninety six corps members who had just been posted to Ahoada-East LGA in southern Nigeria and 83 others that had been in service for six months; were followed up for malaria fever in a prospective cohort design over a 3 month period from September 2010 to December 2010. Active surveillance was used to obtain reports of fever among the cohort; followed by medical examination at designated local health facilities.Results: No significant differences in age and use of protection against malaria were found between the study groups. The incidence proportion of malaria for the recently relocated group (34) was significantly higher than that of the resident group (15.7). Recent change of locality was more associated with malaria fever (RR 2.19; 95 CI 1.243.88; AR 54.4).Conclusion: The recent change of locality within an endemic region; which serves as an indicator of exposure to new variants of P falciparum; for which specific immunity is lacking; is a significant risk factor for malaria fever. Protection against malaria is recommended for semi-immune individuals moving to new locations with significant risk of malaria transmission