Whole-genome sequence analysis reveals the circulation of multiple SARS-CoV-2 variants of concern in Nairobi and neighboring counties, Kenya between March and July 2021.

The emergence and rapid spread of SARS-CoV-2 variants of concern (VOC) have been linked to new waves of COVID-19 epidemics occurring in different regions of the world. The VOC have acquired adaptive mutations that have enhanced virus transmissibility, increased virulence, and reduced response to neutralizing antibodies. Kenya has experienced six waves of COVID-19 epidemics. In this study, we analyzed 64 genome sequences of SARS-CoV-2 strains that circulated in Nairobi and neighboring counties, Kenya between March 2021 and July 2021. Viral RNA was extracted from RT-PCR confirmed COVID-19 cases, followed by sequencing using the ARTIC network protocol and Oxford Nanopore Technologies. Analysis of the sequence data was performed using different bioinformatics methods. Our analyses revealed that during the study period, three SARS-CoV-2 variants of concern (VOC) circulated in Nairobi and nearby counties in Kenya. The Alpha (B.1.1.7) lineage predominated (62.7%), followed by Delta (B.1.617.2, 35.8%) and Beta (B.1.351, 1.5%). Notably, the Alpha (B.1.1.7) VOC were most frequent from March 2021 to May 2021, while the Delta (B.1.617.2) dominated beginning June 2021 through July 2021. Sequence comparisons revealed that all the Kenyan viruses were genetically similar to those that circulated in other regions. Although the majority of Kenyan viruses clustered together in their respective phylogenetic lineages/clades, a significant number were interspersed among foreign strains. Between March and July 2021, our study's findings indicate the prevalence of multiple lineages of SAR-CoV-2 VOC in Nairobi and nearby counties in Kenya. The data suggest that the recent increase in SARS-CoV-2 infection, particularly in Nairobi and Kenya as a whole, is attributable to the introduction and community transmission of SARS-CoV-2 VOC among the populace. In conclusion, the findings provide a snapshot of the SARS-CoV-2 variants that circulated in Kenya during the study period.

Genomic characterization of an African G4P[6] human rotavirus strain identified in a diarrheic child in Kenya: Evidence for porcine-to-human interspecies transmission and reassortment.

Human rotavirus strains having the unconventional G4P[6] genotype have been sporadically identified in diarrheic patients in different parts of the world. However, the whole genome of only one human G4P[6] strain from Africa (central Africa) has been sequenced and analyzed, and thus the exact origin and evolutionary pattern of African G4P[6] strains remain to be elucidated. In this study, we characterized the full genome of an African G4P[6] strain (RVA/Human-wt/KEN/KCH148/2019/G4P[6]) identified in a stool specimen from a diarrheic child in Kenya. Full genome analysis of strain KCH148 revealed a unique Wa-like genogroup constellation: G4-P[6]-I1-R1-C1-M1-A1-N1-T7-E1-H1. NSP3 genotype T7 is commonly found in porcine rotavirus strains. Furthermore, phylogenetic analysis showed that 10 of the 11 genes of strain KCH148 (VP7, VP4, VP6, VP1-VP3, NSP1, and NSP3-NSP5) appeared to be of porcine origin, the remaining NSP2 gene appearing to be of human origin. Therefore, strain KCH148 was found to have a porcine rotavirus backbone and thus is likely to be of porcine origin. Furthermore, strain KCH148 is assumed to have been derived through interspecies transmission and reassortment events involving porcine and human rotavirus strains. To our knowledge, this is the first report on full genome-based characterization of a human G4P[6] strain from east Africa. Our observations demonstrated the diversity of human G4P[6] strains in Africa, and provide important insights into the origin and evolutionary pattern of zoonotic G4P[6] strains on the African continent.

Predominance of Hepatitis B Virus Genotype A Among Treated HIV Infected Patients Experiencing High Hepatitis B Virus Drug Resistance in Nairobi, Kenya.

Hepatitis B virus (HBV)-HIV coinfections are becoming common with information on HBV genetic diversity and drug resistance still remaining elusive. To evaluate the HBV genetic diversity and drug resistance-associated mutations among drug-experienced HIV patients, the genetic analysis of the partial HBV-pol-reverse trancriptase gene was successfully sequenced from 13 samples. Analysis of the sequences showed that all (11) the sequences belonged to genotype A. Nucleos(t)ide drug resistance mutations were found in 6 patients. Five subjects had rtV173L, rtL180M, and rtM204V and one with rtL180M and rtM204V major mutations. HBV genotype A remains the most predominant genotype circulating in Nairobi city with detected high level of HBV drug resistance to lamivudine, telbivudine, and emtricitabine. The detected circulating HBV genotype A in Nairobi reflects its possible spread in the population with its origin being within the country. We suggest that patients should not be on lamivudine monotherapy. These individuals should be managed on combination of tenofovir plus lamivudine or emtricitabine therapy to prevent the emergence of HBV drug resistant variants alongside a continuous surveillance monitoring of drug resistance and HBV genotypes.

Chemokine Coreceptor-2 Gene Polymorphisms among HIV-1 Infected Individuals in Kenya.

Chemokine Coreceptor-2 (CCR2) is an entry coreceptor for HIV-1. A mutation in the coding gene for this coreceptor, CCR2-64I, has been shown to be an important factor for delaying disease progression. In Kenya no studies have been done to determine the status of CCR2 gene polymorphisms among HIV-1 infected individuals. To determine the existence and distribution of CCR2 gene mutations and identify polymorphic groups of the coreceptor gene in the population, a cross-sectional study was conducted to analyze the differences in allelic frequencies of CCR2-64I among HIV-1 seropositive individuals. Blood samples were collected from HIV/AIDS screening centers and analyzed for the presence of CCR2-64I using restriction fragment length polymorphism (RFLP). One hundred and eighteen samples collected from different regions of the country were genotyped for the CCR2-64I mutation. Of these, 4 (3.4%) were homozygous mutants (I/I) and 21 (17.8%) were heterozygous (V/I). Ninety-three subjects (78.8%) were wild type (V/V). With the search for a preventive/therapeutic HIV vaccine elusive, the presence of CCR-2 gene polymorphisms that delay disease progression and prolong the lives of the infected in the Kenyan population may contribute to the growing evidence that host genetic factors are important in predicting susceptibility to HIV-1 infection.

Prevalence of hepatitis B and C viral co-infections among HIV-1 infected individuals in Nairobi, Kenya.

BACKGROUND: Hepatitis B virus (HBV) and Hepatitis C virus (HCV) co-infections among HIV-1 infected individuals are growing worldwide health problems characterized by lack of effective vaccines, need for expensive treatment, chronicity of morbidity and associated mortality. Their prevalence and distribution patterns continue to vary across geographical locations with high prevalence being detected among high risk populations. To determine the prevalence of HBV and HCV among HIV-1 infected individuals, blood samples were collected from consenting study subjects visiting comprehensive HIV clinics in Nairobi during the period between October and December 2009. METHODS: Blood samples from volunteers were screened with ELISA tests for detecting HIV, HBV surface antigen (HBsAg) and anti-HCV antibodies. RESULTS: In a total of three (300) hundred infected individuals consisting of 129 (43%) males and 171 (57%) females 15.3% (46/300) were HIV-1 co-infected with either HBV or HCV or both, 10.3% (31/300) with HIV-1 and HCV and 6% (18/300) with HIV-1 and HBV infections. However, only three individuals (1%) were coinfected with the three viruses (HIV/HBV/HCV). CONCLUSION: Though, low levels of co-infection with all three viruses were reported, there could be higher prevalence rates than reported here especially among high risk populations.