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Background Tea, a widely consumed beverage worldwide increasingly elicits interest due to reported high levels of polyphenols. Polyphenols have been extensively investigated, as they are a potential source of natural antioxidants. Methods The aim of the study was to determine and compare the phytochemical composition and antioxidant activities of aqueous and methanol extracts of black, green, purple, and white teas found in selected regions of Kenya.A total of 56 samples were obtained from tea classified as black, green,purple, and white tea in various factories. The samples were then grounded and extracted using methanol and de-ionized water for 48 hours. The composition of phenolic and tannin contents was determined using Folin- Ciocalteu method. Flavonoids content was determined through the formation of the flavonoids– aluminum complex assay. Antioxidant activity was determined through the DPPH scavenging activity and the iron-reducing power of the extracts. Results The phenolic contents in all samples were significantly higher than flavonoid and tannin levels. In samples extracted with water, the phenolic contents were high (41.74 ± 5.25) mg/g, while flavonoid (0.58 ± 0.06 mg/g) and tannin levels (2.47 ± 0.79) mg/g were relatively low. There was a negative correlation between phytochemicals and the antioxidant activity of the various teas. Conclusions The findings suggest that the different teas have high levels of phytochemicals and are natural antioxidants, however there is no significant variation at p = 0.05 in the composition of phytochemical compounds among the different tea groups.

BackgroundIntestinal parasites are a major public health problem in the developing world and have attracted increasing levels of interest from health researchers over the past decade. Epidemiology-based studies have shown that the prevalence of intestinal parasites is high and they frequently recur in regions with poor sanitation and inadequate sewerage facilities. In this study, we determined the prevalence of intestinal parasites, their egg intensities per sample, and associated risk factors in an informal settlement.MethodsThis was a cross-sectional study conducted in three randomly selected public primary schools located in the informal settlements of Nakuru town. A total of 248 stool samples were collected from asymptomatic pupils and screened, using the Kato Katz technique, for infections caused by soil-transmitted helminths (STH). A random subset of stool samples (n=96) was also screened by polymerase chain reaction (PCR) to detect intestinal protozoa. Socio-demographic variables were collected using a pre-tested structured questionnaire; these data were analysed to identify risk factors for infection. ResultsThe overall prevalence of intestinal parasites was 17.3% (43/248 pupils). The overall prevalence of both STH and intestinal protozoan parasites was 1.2% and 41.7%, respectively. The most commonly diagnosed STH infection was Trichuris trichiura (1.2%), followed by hookworms (0.4%) and Ascaris lumbricoides (0.4%). The prevalence of intestinal protozoan parasites ranged from 0% to 38.5% and included Entamoeba histolytica, Entamoeba hartmanni, Entamoeba dispar, Giardia intestinalis, and Entamoeba coli. All infections were light, with an egg intensity

BACKGROUND Universal access to highly active antiretroviral therapy (HAART) is still elusive in most developing nations. We asked whether peer support influenced adherence and treatment outcome and if a single viral load (VL) could define treatment failure in a resource-limited setting. METHODS A multicenter longitudinal and cross-sectional survey of VL, CD4 T cells, and adherence in 546 patients receiving HAART for up to 228 months. VL and CD4 counts were determined using m2000 Abbott RealTime HIV-1 assay and FACS counters, respectively. Adherence was assessed based on pill count and on self-report. RESULTS Of the patients, 55.8%, 22.2%, and 22% had good, fair, and poor adherence, respectively. Adherence, peer support, and regimen, but not HIV disclosure, age, or gender, independently correlated with VL and durability of treatment in a multivariate analysis (P < 0.001). Treatment failure was 35.9% using sequential VL but ranged between 27% and 35% using alternate single VL cross-sectional definitions. More patients failed stavudine (41.2%) than zidovudine (37.4%) or tenofovir (28.8%, P = 0.043) treatment arms. Peer support correlated positively with adherence (χ(2), P < 0.001), with nonadherence being highest in the stavudine arm. VL before the time of regimen switch was comparable between patients switching and not switching treatment. Moreover, 36% of those switching still failed the second-line regimen. CONCLUSION Weak adherence support and inaccessible VL testing threaten to compromise the success of HAART scale-up in Kenya. To hasten antiretroviral therapy monitoring and decision making, we suggest strengthening patient-focused adherence programs, optimizing and aligning regimen to WHO standards, and a single point-of-care VL testing when multiple tests are unavailable.

HIV genetic recombination and high mutation rate increase diversity allowing it to escape from host immune response or antiretroviral drugs. This diversity has enabled specific viral subtypes to be predominant in specific regions. To determine HIV-1 subtypes among seropositive antenatal clinic attendees in Kenya's North Rift Valley, a cross-sectional study was carried out on 116 HIV-1-positive blood samples. Proviral DNA was extracted from peripheral blood mononuclear cells by DNAzol lysis and ethanol precipitation. Polymerase chain reactions using specific primers for HIV-1 gag and population sequencing on resulting amplicons were carried out. Phylogenetic analysis revealed that 81 (70%) were subtype A1, 13 (11%) subtype D, 8 (7%) subtype C, 3 (3%) subtype A2, 1 (1%) subtype G, and 10 showed possible recombinants: 5 (4%) subtype A1D, 4 (3%) subtype A1C, and 1 (1%) subtype A2C. These data support the need to establish circulating subtypes for better evaluation of effective HIV diagnostic and treatment options in Kenya.

Monitoring the distribution of HIV-1 subtypes and recombinants among infected individuals has become a priority in HIV therapy. A laboratory analysis of samples collected from HIV-positive patients attending an STI clinic in Nairobi was done between March and May 2004. PCR was carried out on pol (intergrase) and env (C2V3) regions and resulting data on the 54 samples successfully analyzed revealed the following as circulating subtypes: 35/54(65%) were A1/A1, 5/54(9%) were A/C, 4/54 (7%) were A1/D, 1/54 (2%) was C/D, 1/54 (2%) was D/D, 1/54 (2%) was A1/A2, 1/54 (2%)was G/G, 1/54 (2%) was A2/D, 1/54 (2%) was C/C, and 4/54 (7%) were CRF02_ AG. The results show an increase in HIV-1 recombinants with the emergence of A1/A2 and an increase in CRF02_AG recombinants. Subtype diversity in the advent of ARV use will impact negatively on treatment outcomes. As such, increased viral evolution and recombination will call for continuous evaluation of available anti-HIV regimens for better management of those infected with HIV-1.

The genetic subtypes of HIV-1 circulating in northern Kenya have not been characterized. Here we report the partial sequencing and analysis of samples collected in the years 2003 and 2004 from 72 HIV-1-positive patients in northern Kenya, which borders Ethiopia, Somalia, and Sudan. From the analysis of partial env sequences, it was determined that 50% were subtype A, 39% subtype C, and 11% subtype D. This shows that in the northern border region of Kenya subtypes A and C are the dominant HIV-1 subtypes in circulation. Ethiopia is dominated mainly by HIV-1 subtype C, which incidentally is the dominant subtype in the town of Moyale, which borders Ethiopia. These results show that cross-border movements play an important role in the circulation of subtypes in Northern Kenya.

Hepatitis C virus is a great public-health concern worldwide. Phylogenetic analysis of the HCV genome has identified six different genotypes that have generally been divided into several subtypes. There is very little information on HCV seroprevalence and genotypes in Kenya. To determine the genotypes of HCV circulating in Kenya, blood donor samples were serologically tested and confirmed by polymerase chain reaction (PCR). Positive samples were cloned and sequenced, and phylogenetic analysis conducted to determine the HCV genotypes. One hundred Murex-seropositive samples were re-tested using a passive hemagglutination test, and 16 of these were identified as seropositive. Further testing of all of the samples by PCR identified only 10 of the 16 samples as positive. Thus, only 10 % (10/100) of the samples were viremic. Six were from females (60 %), and four were from males (40 %). The mean age of the positive donors was considerably low, at 25 +/- 9 years. Genotypic testing indicated the presence of genotype 1a (10 %) and genotype 2b (90 %). This study reports on HCV genotypes in a blood donor population in Kenya where little had been done to provide information on HCV genotypes.

Background HIV-1 phenotype variability plays an important role in HIV-1 transmission and pathogenesis of AIDS. The basis of heterogeneity between the phenotypes is known to be the differential use of chemokine receptors as co-receptors for viral entry. Beta Chemokine receptor-5 (CCR5) using variants are associated with acute infections, macrophage tropism, non syncytium inducing (NSI) phenotype and slow progression to AIDS. Alpha chemokine receptor-4 (CXCR4) using variants evolve later in infection in about 50 % of the patients and are associated with T cell lines tropism, syncytium induction, accelerated T cell depletion and Rapid progression to AIDS. HIV-1 co-receptor usage and phenotypes are mapped in the third variable region (V3) of the gp120 env gene. Methods One hundred and thirty five (135) whole blood samples were collected from HIV-1 infected patients in Northern Kenya. Proviral DNA was extracted using DNazol and ethanol precipitation. HIV-1 V3 region was amplified by nested PCR using C2V3 primers. Amplicons were sequenced directly using Big Dye technology in the ABI Prism Genetic Analyzer to generate gp120 V3 loop sequences. Bioinformatics tools were used to determine co-receptor usage from the sequences obtained. Results CXCR4 usage was most dominant with 94 out of 135 samples(69.6 %) using this co-receptor compared to CCR5 which was used by 29 of the 135 (21.8 %) samples and dual co-receptor usage found in 12 of the 135(8.6%) samples tested. Conclusion Most patients were inferred to be in late stages of infection and likely to be rapidly progressing to AIDS. Based on these results from co-receptor usage data, HIV-1 incidence rate was likely to be low. Co-receptor usage was observed to be associated with HIV-1 subtypes. Poor alignment of the Northern Kenya sequences with the training data for the classifier software necessitates the need for development of Bioinformatic software relevant for locally circulating HIV-1 subtypes.

Antiretroviral therapy (ART) has improved the survival of HIV patients but is also associated with unique manifestations of disease in some subjects during the initial months of therapy. Immune reconstitution inflammatory syndrome (IRIS) is a disorder among individuals starting ART, with no evidence-based treatment and management guidelines. We characterized HIV-1 and determined drug resistance among 14 Kenyan patients with suspected IRIS after ART initiation in 2005. Polymerase chain reaction, sequencing, and phylogenetic analysis of viral pol and env showed the following HIV-1 subtypes: A1/A1/A1 (pol-RT/gp41/C2V3), 5; A1/C/A1, 1; A1/D/A1, 2; D/A1/A1, 1; D/C/A1, 1; D/D/A1, 2; D/D/D, 1; and D/A1/A2, 1. Three patients had viruses with major drug resistance-associated mutations. These included nucleoside reverse transcriptase inhibitor (RTI) mutations: M41L, K65R, D67N, K70R, M184V, and K219Q, and nonnucleoside RTI mutations: K101P, L100I, K103N, and Y181C. Twelve patients harbored viruses that are predicted to use chemokine coreceptor 5 (CCR5) whereas two had variant viruses predicted to use the CXCR4 coreceptor. Drug resistance may not be the only cause of ART adverse events. HIV-1 characterization would be important before and during HIV therapy to avoid treatment failure.

The treatment of HIV-1 infection with antiretroviral drugs has greatly improved the survival of those who are infected. However, HIV-1 diversity and drug resistance are major challenges in patient management, especially in resource-poor countries. To evaluate HIV-1 genetic diversity and drug resistance-associated mutations among drug-naive patients in Kenya prior to antiretroviral therapy (ART), a genetic analysis of HIV-1 pol-RT and env-gp41 was performed on samples collected from 53 (18 males and 35 females) consenting patients between April and June 2005. The average age, baseline CD4(+) T cell counts, and viral loads were 38 (range, 24-62) years, 475 (range, 203-799) cells/mm(3), and 4.7 (range, 3.4-5.9) log(10) copies/ml, respectively. Phylogenetic analysis revealed that 40 samples (75.5%) were concordant subtypes for the two genes and 13 (24.5%) were discordant, suggesting possible recombination and/or dual infections. Prevalent subtypes included A1/A1(pol-RT/env-gp41), 31 (58.5%); D/D, 9 (16.9%); A1/C, 2 (3.8%); A1/D, 4 (7.5%); G/A1, 2 (3.8%); A1/A2, 1 (1.9%); C/A1, 2 (3.8%); D/A1, 1(1.9%); and D/A2, 1 (1.9%). Major reverse transcriptase inhibitor (RTI) resistance-associated mutations were found in four patients (7.5%). Of these patients, three had nucleoside RTI resistance mutations, such as M184V, K65R, D67N, K70R, and K219Q. Nonnucleoside RTI resistance-associated mutations K103N and Y181C were detected in three patients and one patient, respectively. Multiple drug resistance mutations were observed in this drug-naive population. With increasing numbers of patients that require treatment and the rapid upscaling of ART in Kenya, HIV-1 drug resistance testing is recommended before starting treatment in order to achieve better clinical outcomes.

A study on the genetic diversity of HIV-1 subtypes present along the coastal strip of Kenya, i.e., Kilifi, Mombasa, Msambweni, and Malindi districts, was carried out. DNA sequences for regions encoding a portion of the env-gp41 region of the virus were generated by PCR and sequenced directly. Eighty six samples that were successfully sequenced were analyzed. From the analysis, 86% (74) were subtype A1, 5% (4) were subtype C, 8% (7) were subtype D, and 1% (1) was subtype G. This study shows that HIV-1 subtype A1 is the most dominant subtype in circulation in this region.

The use of single dose nevirapine to prevent mother-to-child transmission of HIV has been reported to induce drug-resistant mutations and reduce options for antiretroviral treatment for HIV-infected mothers and their children. To explore the status of nevirapine-resistant HIV genotypes in rural hospitals in the North Rift Valley Province of Kenya, samples collected 3 months after single dose nevirapine from 36 mothers and their children were analyzed. Resistance mutations were genotypically evaluated through proviral DNA amplification, cloning, and sequencing. Ten mothers (27.8%) had antiretroviral-associated resistance mutations of whom four (11.1%) had specific nevirapine (NNRTI) resistance-associated mutations. Three mothers (8.3%) transmitted the infection to their infants. This presence of nevirapine mutations in rural antenatal clinic attendees confirms the importance of integrating antiretroviral resistance monitoring as a key component in programs geared to prevention of HIV mother-to-child transmission.

The genetic diversity of HIV-1 subtypes circulating in three districts of northern Kenya, i.e., Turkana, Mandera, and Moyale, was studied. DNA sequences encoding a portion of the env-C2-V3 region of the virus were amplified by PCR and sequenced directly. One hundred and fifty-nine samples were successfully sequenced in the env-C2-V3 region and analyzed. From the analysis, 57% were subtype A1, 27% were subtype C, 9% were subtype D, and the remaining 7% were unclassified. This study showed that HIV-1 subtype A1 was the dominant subtype in circulation in this region, though there was a significant percentage of HIV-1 subtype C in circulation there.

Eight genotypes of hepatitis B virus (A-H) and subgenotypes have been recognized worldwide. However, there is limited information on prevalent genotypes in many countries in Africa. This study was undertaken to determine the hepatitis B virus (HBV) genotypes in Kenya. Seropositive HBV blood samples from a blood donor setting were used in the study. HBV genotypes were determined in 52 nucleic acid-positive samples using specific primer in a nested PCR and sequencing employed in the HBV genotyping. This study shows presence of HBV variants with genotypes A (88%), E (8%) and D (4%). In conclusion, we found that HBV genotype A is the most predominant genotype in Kenya with both subgenotype A1 and A2 present. Genotype D and E are also present in our population. This demonstrates that there could be a high genetic diversity of HBV in Kenya.

Circulating strains of human immunodeficiency virus (HIV) exhibit an extraordinary degree of genetic diversity and have been classified on the basis of relationships into distinct lineages called groups, types, subtypes, and subsubtypes. Sexually transmitted infections (STIs) are known to be a risk factor for HIV infection. To establish HIV-1 subtype diversity among STI patients in Nairobi, 140 samples were collected and partial pol gene sequencing done. From the analysis it was established that subtype A1 was the major subtype (64%) followed by D (17%), C (9%), G (1%), and recombinants AD (4%), AC (3%), CRF02()AG (1%), and CRF16()A2D (1%). These results suggest that the HIV-1 epidemic may be evolving toward more virulent and complex subtypes through transmission of complex recombinants due to viral mixing. Any use of ARVs may therefore require initial testing for de novo resistance before commencement of treatment and/or management.

Background Access to antiretroviral therapy (ART) has increased dramatically in Sub-Saharan Africa. In Kenya, 560,000 people had access to ART by the end of 2011. This scaling up of ART has raised challenges to the Kenyan health system due to emergence of drug resistant viruses among those on treatment and possible onward transmission. To counter this, and come up with an effective treatment strategy, it has become vital to determine baseline mutations associated with drug resistance among the circulating strains of HIV-1in Kenya. Methods The prevalence of mutations associated with drug resistance in HIV-1 protease (PR) and reverse transcriptase (RT) regions from 188 HIV-1 infected treatment-naïve pregnant women was investigated in Kapsabet, Nandi Hills and Kitale district hospitals of Kenya. Blood samples were collected between April 2005 and June 2006. The HIV-1 pol gene was amplified using primers for HIV-1 PR and RT and sequenced using the BigDye chemistry. The mutations were analyzed based on the IAS algorithm as well as the Stanford University HIV Drug Resistance Database. Results Based on the PR and RT sequences, HIV-1 subtypes A1 (n=117, 62.2%), A2 (n=2, 1.1%), D (n=27, 14.4%), C (n=13, 6.9%), G (n=3, 1.6%), and possible recombinants (n=26, 13.8%) were detected. Mutations associated with nucleoside reverse transcriptase inhibitors (NRTI) and non-nucleoside RTI (NNRTI)-resistance were detected in 1.6% (3 of 188) and 1.1% (2 of 188), respectively. Mutations associated with PI resistance were detected in 0.5% (1 of 188) of the study population. Conclusion The prevalence of drug resistance among drug-naïve pregnant women in rural North Rift, Kenya in 2006 was 3.2%. Major drug resistance mutations associated with PIs, NRTIs and NNRTIs do exist among treatment-naïve pregnant women in North Rift, Kenya. There is a need for consistent follow-up of drug-naïve individuals in this region to determine the impact of mutations on treatment outcomes.