RP-Deparment of Medical Laboratory Sciences

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Immunization of Mice and Baboons with the Recombinant Sm28GST Affects Both Worm Viability and Fecundity after Experimental Infection with Schistosoma Mansoni.
(PubMed, 1991-09) Otieno, Micheal Frederick; Boulanger, D.; Reid, G. D.; Sturrock, R. F.; Wolowczuk, I.; Balloul, J. M.; Grezel, D.; Pierce, R. J.; Guerret, S.; Grimaud, J. A.
A member of the glutathione S-transferase family, Sm28GST has previously demonstrated a good ability to protect rodents against experimental infection with Schistosoma mansoni. In order to evaluate its efficacy in a model closer to man, two different protocols of immunization with recombinant Sm28GST were tested on baboons in a large-scale trial. Three injections in the presence of aluminium hydroxide as adjuvant resulted in a significant 38% reduction in the adult worm burden together with a trend for a lower percentage of inflammatory tissue in the liver. Individual levels of protection, ranging from 0 to 80%, underlined the heterogeneity of the immune response to this purified molecule in outbred primates. On the other hand, two injections of Sm28GST in the presence of aluminium hydroxide and Bordetella pertussis reduced female schistosome fecundity by 33%, with a more pronounced effect (66%) on faecal egg output; there was also a trend, in this protocol, for decrease of the mean granuloma surface in the liver. Individual anti-Sm28GST IgG antibodies were apparently unrelated to levels of immunity, but there was partial evidence that cytophilic IgE might play a role in the immune mechanisms affecting worm viability, but not fecundity. In the mouse model, Sm28GST vaccination resulted in a lower hatching ability of tissue eggs recovered from immunized mice whereas passive transfer of specific anti-Sm28GST T-lymphocytes, one day before infection, significantly reduced the number of eggs in the liver of mice. We propose that different protocols of immunization with a recombinant molecule can impede Schistosoma mansoni worm viability and fecundity, but can also affect miracidium physiology, with important consequences for disease transmission and granuloma-derived pathology.
Combining Evidence of Natural Selection with Association Analysis Increases Power to Tetect Malaria-Resistance Variants.
(PubMed, 2007) Otieno, Micheal Frederick; Ayodo, G.; Price, A. L.; Keinan, A.; Ajwang, A.; Orago, A. S.; Patterson, N.; Reich, D.
Statistical power to detect disease variants can be increased by weighting candidates by their evidence of natural selection. To demonstrate that this theoretical idea works in practice, we performed an association study of 10 putative resistance variants in 471 severe malaria cases and 474 controls from the Luo in Kenya. We replicated associations at HBB (P=.0008) and CD36 (P=.03) but also showed that the same variants are unusually differentiated in frequency between the Luo and Yoruba (who historically have been exposed to malaria) and the Masai and Kikuyu (who have not been exposed). This empirically demonstrates that combining association analysis with evidence of natural selection can increase power to detect risk variants by orders of magnitude--up to P=.000018 for HBB and P=.00043 for CD36.
Polymorphic Variability in the Interleukin (IL)-1Beta Promoter Conditions Susceptibility to Severe Malarial Anemia and Functional Changes in IL-1Beta Production
(PubMed, 2008-10) Otieno, Micheal Frederick; Ouma, C.; Davenport, G. C.; Awandare, G. A.; Keller, C. C.; Were, T.; Vulule, J. M.; Martinson, J.; Ong'echa, J. M.; Ferrell, R. E.; Perkins, D. J.
Interleukin (IL)-1beta is a cytokine released as part of the innate immune response to Plasmodium falciparum. Because the role played by IL-1beta polymorphic variability in conditioning the immunopathogenesis of severe malarial anemia (SMA) remains undefined, relationships between IL-1beta promoter variants (-31C/T and -511A/G), SMA (hemoglobin [Hb] level <6.0 g/dL), and circulating IL-1beta levels were investigated in children with parasitemia (n= 566) from western Kenya. The IL-1beta promoter haplotype -31C/-511A (CA) was associated with increased risk of SMA (Hb level <6.0 g/dL; odds ratio [OR], 1.98 [95% confidence interval {CI}, 1.55-2.27]; P < .05) and reduced circulating IL-1beta levels (p <.05). The TA (-31T/-511A) haplotype was nonsignificantly associated with protection against SMA (OR, 0.52 [95% CI, 0.18-1.16]; p =.11) and elevated IL-1beta production ( p<.05). Compared with the non-SMA group, children with SMA had significantly lower IL-1beta levels and nonsignificant elevations in both IL-1 receptor antagonist (IL-1Ra) and the ratio of IL-1Ra to IL-1beta. The results presented demonstrate that variation in IL-1beta promoter conditions susceptibility to SMA and functional changes in circulating IL-1beta levels.
Prevalence and Antimicrobial Susceptibility of Enterobacteriaceae Collected from Patients with Wounds at Kenyatta National Hospital
(2009) Karimi, P.N.; Bururia, J.M.; Odhiambo, P.A.; Amugune, B.k.; Museve, G.O.
Prevalence and sensitivity trends of Enterobacteriaceae isolated from septic wounds were determined through a prospective cross sectional study. One hundred and fifteen specimens isolated from in-patients in the Department of Orthopaedics were studied and antibiotic sensitivity testing performed using the Kirby and Bauer disc diffusion technique. The prevalence of organisms isolated was Proteus spp (33.9%), Eschericia coli (13.2%), Klebsiella spp (7.9%), Alcaligenes (1.7%), Citrobacter freundii (0.9%), Serratia spp (0.9%) and Acinetobacter baumanii (0.9%). The sensitivity rate of ceftriaxone, ceftazidime and ciprofloxacin was above 70% in all cases. Co-amoxiclav, gentamicin, cefuroxime, minocycline and piperacillin showed moderate to high activity. Klebsiella spp isolates portrayed high resistance against several drugs. The sensitivity patterns showed that empirical prescribing should be discouraged since the organisms appear to be developing resistance against commonly used antibiotics.
Evolutionary Pattern of the Hemagglutinin Gene of Influenza B Viruses Isolated in Kenya 2005-2009
(African Journal of Health Sciences, 2011-06-17) Gachara, George; Bulimo, W.; Magana, J.; Simwa, J.; Symekher, S.
Background: In humans, the inability to provide lasting protection against influenza B virus infection is due, in part, to the rapid evolution of the viral surface glycoprotein, haemagglutinin (HA), which leads to a change in its antigenic nature. Therefore, the evolution of the haemagglutinin (HA) an important influenza antigen has and continues to be a subject of intensive research. In this study, we analyzed the evolution occurring in the haemagglutinin of influenza B viruses from Kenya since virological surveillance began in 2005. Methods: Thirty (30) influenza B haemagglutinin sequences of viruses isolated from different parts of the country between 2005-2009 at the NIC were analyzed. Nucleotide sequences, prediction of amino acid sequences, alignments, and phylogenetic tree construction were completed using BioEdit and MEGA® software Results: During the five year study period, the two influenza B lineages B/Yamagata and B/Victoria have co-circulated in two years (2005 and 2007) while B/Yamagata viruses exclusively circulated in 2008 and B/Victoria viruses in 2006 and 2009. The nucleotide sequence identity ranged from 92.9% – 97.0% among the B/Yamagata lineage viruses and 90.6% – 98.5% among the B/Victoria lineage viruses. There was generally noted more amino acid substitutions among the B/Yamagata lineage than the B/Victoria lineage. Substitutions were observed in all the epitope regions among B/Yamagata viruses compared to three epitopes in the B/Victoria viruses. Both lineages showed substitutions at position HA1 165. Conclusions: These results demonstrate that distinct viruses within the two lineages have been co-circulating in the country every year and that there has been a greater evolution of the B/Yamagata viruses. At the same time it is noted that like elsewhere, influenza B viruses in the country have continually been evolving by antigenic drift. In-order to understand whether reassortments have occurred, the study suggests periodic complete genomic sequencing of select.
Identification and Susceptibility Profile of Vaginal Candida Species to Antifungal Agents among Pregnant Women Attending the Antenatal Clinic of Thika District Hospital, Kenya
(Scientific Research Publishing, 2013) Menza, Nelson; Wanyoike, Wanjiru; Muturi, Margaret
Fungal infections have emerged as a world-wide health care problem in recent years, owing to the extensive use of broad-spectrum antibiotics. We screened 104 pregnant women with symptoms of vaginal candidiasis in the antenatal clinic of Thika District Hospital, Kenya in order to identify vaginal Candida species and determine their susceptibility profile to commonly used antifungal drugs for treatment of the infection. The drugs tested were fluconazole, ketoconazole, itraconazole, clotrimazole and topical nystatin. Vaginal swabs were collected and subjected to mycological and biochemical tests for Candida species identification. Susceptibility profile of the identified vaginal Candida species to the antifungal drugs was carried out using broth micro-dilution minimum inhibiting concentration method based on the approved National Committee for Clinical Laboratory Standards (NCCLS, 2002) guidelines. Candida albicans was susceptible to most of the azoles drugs while the other species had varying responses. Candida krusei and Candida glabrata species isolated were resistant to fluconazole and ketoconazole. Candida albicans isolates had a high susceptibility to itraconazole (88.33%). Five percent (5%) of the isolates were susceptible in dose dependent (S-DD) with Minimum Inhibitory Concentrations (MICs) of 0.25 - 0.5 µg/ml while 11.67% of C. albicans isolates were resistant (MICs ≥ 1 µg/ml). Itraconazole resistance was highest among C. glabrata isolates (50%) while 32.14% were S-DD (MICs 0.25 - 0.5 µg/ml). Only 17.85% of the C. glabrata isolates were susceptible (MICs of ≤ 0.125 µg/ml). All isolates of Candida isolates were susceptible to itraconazole and clotrimazole except C. krusei which was 100% resistant to clotrimazole. All Candida species isolates had low susceptibility to topical nystatin except Candida parapsilosis that was 100% susceptible. Data also showed an emerging resistance of Candida krusei to most of the drugs used except itraconazole. The results of this study support the continued use of these antifungal drugs for the treatment of vaginal candidiasis in the pregnant women except topical nystatin.
Human Bocavirus Infection in Children with Acute Respiratory Infection in Nairobi, Kenya
(Scientific Research Publishing, 2013-12) Gachara, George; Symekher, S.L.; Simwa, J.; Gichogo, J.; Rotich, M.; Ng’ayo, M.O.; Magana, J.
Background: Acute respiratory infection (ARI) is a leading cause of morbidity and mortality in children under five years of age in developing countries with viruses contributing significantly to this problem. The recently identified par-vovirus, Human Bocavirus (HBoV), has also been associated with ARI. Objective: To determine the frequency of HBoV in patients with ARI. Materials and Methods: Samples from 125 consenting patients with influenza like illness signs and symptoms were collected. DNA was extracted from these samples using the QIAamp DNA blood mini kit (Qiagen, Germany). Conventional PCR was carried out and the amplicons were examined in 2% agarose gels stained with ethidium bromide. This was followed by sequencing of the HBoV positive samples. Results: Twenty one (16.8%) patients were found to have HBoV infection. Males (n = 61.9%) were mainly infected with HBoV. Local HBoV strains had 98.9% - 100% similarities and were found to cluster together with other strains obtained elsewhere. Conclusion: These findings suggest that HBoV plays a role in respiratory tract infections in children in Kenya just like it has been found elsewhere. It also sheds light on multiple infections associated with HBoV infections in Kenya
Coagulation Factors Level in Fresh Frozen Plasma in Rwanda
(Kenya Medical Association, 2014) Nyamache, A. K.; Uwamungu, S; Masaisa, F.; Njoki, S.K.; Abdalah, F.; Saibu, K.; Ndahiriwe, O.; Agwata, D.
Objectives: To determine the level of coagulation factors and inherited inhibitors in Fresh Frozen Plasma (FFP) and to evaluate Prothrombin Time and activated partial thrombin time in fresh frozen plasma. Design: Cross-sectional study. Setting: Jomo Kenyatta University of Agriculture and Technology in Medical Laboratory Sciences. Subjects: Eighteen blood bags collected from voluntary blood donors. Main outcome measures:Coagulation factors and inhibitors levels, Prothrombin Time (PT) and Activated Partial thrombin Time (APTT)remained within the reference range requested by quality assurance regulations after three months of storage. Results: APTT and PT show an increase from baseline to one month then remain constant up to three months, while, Fibrinogen, Factor II, Factor V, Factor VII, Factor X, Von Willbrand Factor, Protein C and Antithrombin decreased from baseline up to three months and then Factor VIII, Factor IX, Factor XI, Factor XII and Protein S, remained constant from baseline up to one month and decreased up to three months. Conclusion: There is good retention of all coagulation factors and inhibitors in plasma produced from whole blood within eight hours of collection, stored at minus 18ºC for three months
HIV type 1 drug resistance patterns among patients failing first and second line antiretroviral therapy in Nairobi, Kenya
(BioMed Central, 2014) Nyamache, A. K.; Koigi, P.; Ngayo, Musa Otieno; Khamadi, Samoel; Ngugi, Caroline
Background: The ever-expanding rollout of antiretroviral therapy in poor resource settings without routine virological monitoring has been accompanied with development of drug resistance that has resulted in limited treatment success. Methods: A cross-sectional study with one time viral load was conducted during the period between 2012 and 2013 to determine treatment failure and drug resistance mutations among adults receiving first-line (44) (3TC_d4T/ AZT_NVP/EFV) and second-line (20) (3TC/AZT/LPV/r) in Nairobi, Kenya. HIV-1 pol-RT genotyping for drug resistance was performed using an in-house protocol. Results: A total of 64 patients were recruited (mean age 36.9 yrs.) during the period between 2012 and 2013 of the 44 adult patients failing first-line 24 (40.9%) had drug resistance mutations. Eight (8) patients had NRTI resistance mutations with NAMS M184V (54.2%) and K65R (8.4%) mutations being the highest followed by TAMs T215Y and K70R (12.5%). In addition, among patients failing second-line (20), six patients (30%) had NNRTI resistance; two patients on K103N and G190A mutations while V106A, Y184V, A98G, Y181C mutations per patient were also detected. However, for NRTI two patients had TAM T215Y. M184V mutation occurred in one patient. Conclusions: The study findings showed that HIV-1 drug resistance was significantly high in the study population. The detected accumulated resistance strains show that emergence of HIV drug resistance will continue to be a big challenge and should be given more attention as the scale up of treatment in the country continues
Burden of Human Rhinovirus Infections in Influenza like Illnesses in Kenya
(Elsevier, 2014) Kaburu, S. M.; Bulimo, W.; Maina, G. G.; Ongus, J.
Background: There have been several recent reports of respiratory outbreaks with associated mortality due to human rhinovirus (HRV) infection. Studies on viral etiologies of Influenza-like illness have shown that many patients are infected with more than one viral agent with frequencies of co-infection being as high as 20%. From these studies, human rhinovirus has been shown as one of the most prominent respiratory viruses that co-infect patients with influenza. In Kenya, the ongoing Influenza surveillance has provided data that now allows for exploration of other respiratory viruses that cause influenza-like illnesses. Currently, there is scanty information on the patterns of HRV circulation throughout the country. Methods & Materials: This study utilized a retrospective cross-sectional descriptive design. It involved the use of 517 archived samples from the ongoing country-wide influenza Surveillance protocol. The archived nasopharyngeal specimens were collected from a study population comprising persons from two months of age onwards who attended outpatient clinics in the year 2008, in hospitals located in 8 different regions in Kenya presenting with influenza like illnesses. Viral RNA was extracted from the samples followed by real-time RT-PCR assays with HRV-specific primers for screening for HRV. Results: A total of 131 (25%) of the samples were positive for HRV. The highest prevalence (33%) was recorded from samples obtained from the Coast region of the country, followed by Western region (32.7%) while Eastern region had the lowest prevalence (11%). Children aged between 2 months -7 years were mostly infected while the age group ≥60 years was least affected. There was no significant difference in HRV infection in relation to gender. Conclusion: The study notes that HRV infection is a significant viral etiology of morbidity throughout the country. However, disparities were observed between different regions. The more humid regions in the country (Western and Coast) had the highest HRV prevalence. At the same time, children below 7 years were at a greater risk of HRV infection. Determination of the molecular characteristics of the rhinovirus strains to enable specific identification of the species and the evolutionary relationships is ongoing.
Potency status of oral polio virus vaccine among retrieved field samples in Kenya
(Elsevier, 2014-04) Gachara, George; Hassan, J. A.; Mbugua, F.; Muchiri, J.; Symekhah, S.; Nakitari, G.; Borus, P.; Kamau, T.; Kombich, J.
Background: In 1988 the World Health Organization (WHO) proposed mass immunization campaigns with the trivalent oral polio vaccine (TOPV) among children less than 5 years of age. The Vaccine Vial Monitor (VVM) is a small patch of heat-sensitive material placed on the vaccine vial to register cumulative heat exposure. A direct relationship exists between the rate at which the VVM changes colour and ambient temperature. This in turn affects the potency of the oral polio vaccine. [1] Objectives: To evaluate the status of the cold chain infrastructure in Kenya and to determine the total TOPV virus concentration of retrieved field samples. Methods & Materials: A stratified multi-stage sampling strategy was used leading to selection of 14 health centres this study. A total of 23 TOPV vial samples were collected, separated into individual serotypes generating 69 samples for the potency test. Potency of oral polio vaccine was tested using Karber's formula. This was then compared to the Vaccine Vial Monitor stage of the vials Results: Our study showed that the average potency of polio vaccine serotype1, serotype 2 and serotype 3 were as follows; Comparison between VVM1/VVM 2 and Serotype titres calculated Polio 1 standard (Mean titre) Polio 1 Test (Calculated Mean Titre) Polio 2 standard (Mean titre) Polio 2 test (Calculated mean Titre) Polio 3 Standard (Mean titre) Polio 3 test (Calculated mean Titre) VVM 106 106.05 105 104.98 105.5 105.73 1 106 106.03 105 105.08 105.5 105.35 2 Table options *The mean titre was calculated using the Karber's formula[Log CCID50 = L-d(S-0.5)]]with an allowance of + 0.5 log units Conclusion: On average the vaccine vials used in the study were potent with satisfactory VVM and mean serotype titre. We found that some OPV vials had dissatisfactory VVM stage. Vaccine potency was seen to be directly proportional to VVM stage of vaccine vials. Vaccine vials kept at temperatures below -18 °C had a better VVM leading to a better potency status. Some OPV Samples which had lower titre of serotype 2 were contributed to by the temperature of the equipment they were stored at.
Whole genome characterization of human influenza A(H1N1)pdm09 viruses isolated from Kenya during the 2009 pandemic
(Elsevier, 2016) Gachara, George; Symekher, S.; Otieno, M.; Magana, J.; Opot, B.; Bulimo, W.
An influenza pandemic caused by a novel influenza virus A(H1N1)pdm09 spread worldwide in 2009 and is estimated to have caused between 151,700 and 575,400 deaths globally.Whilewhole genome data on newvirus enables a deeper insight in the pathogenesis, epidemiology, and drug sensitivities of the circulating viruses, there are relatively limited complete genetic sequences available for this virus from African countries. We describe herein the full genome analysis of influenza A(H1N1)pdm09 viruses isolated in Kenya between June 2009 and August 2010. A total of 40 influenza A(H1N1)pdm09 viruses isolated during the pandemic were selected. The segments from each isolate were amplified and directly sequenced. The resulting sequences of individual gene segments were concatenated and used for subsequent analysis. These were used to infer phylogenetic relationships and also to reconstruct the time of most recent ancestor, time of introduction into the country, rates of substitution and to estimate a time-resolved phylogeny. The Kenyan complete genome sequences clustered with globally distributed clade 2 and clade 7 sequences but local clade 2 viruses did not circulate beyond the introductory foci while clade 7 viruses disseminated country wide. The time of the most recent common ancestor was estimated between April and June 2009, and distinct clusters circulated during the pandemic. The complete genome had an estimated rate of nucleotide substitution of 4.9 × 10−3 substitutions/site/year and greater diversity in surface expressed proteins was observed. We show that two clades of influenza A(H1N1)pdm09 virus were introduced into Kenya from the UK and the pandemic was sustained as a result of importations. Several closely related but distinct clusters co-circulated locally during the peak pandemic phase but only one cluster dominated in the late phase of the pandemic suggesting that it possessed greater adaptability
Non-Hepatic Adverse Effects of Antiretroviral Therapy for HIV Treatment and Care
(Adis, Springer Healthcare, 2016) Wambani, J.R.; Ogola, P.E.; Makori, A.W.; Rachuonyo, H.O.; Kiboi, N.G.
High-level viral replication occurs when HIV enters the body. Due to frequent mutations, the virus becomes resistant in the body and persists in memory T cells making it incurable. Lifelong therapy is then required to suppress replication of the virus in the cells. The drugs available for HIV care such as Non-nucleoside reverse transcriptase inhibitors, Protease Inhibitors, Nucleoside reverse transcriptase inhibitors, Entry and Fusion Inhibitors and Integrase inhibitors have been documented to cause adverse effects in patients. Non-nucleoside reverse transcriptase inhibitors and protease inhibitors are metabolized by the cytochrome P450 system, resulting to numerous drug-drug interactions. Adverse effects of antiretroviral therapy should be monitored frequently. Monitoring should include complete blood counts and comprehensive metabolic profiles every three to six months. Lipid profiles and urinalysis for proteinuria should be done after every year. Long-term morbidity due to antiretroviral therapy includes renal, liver, glucose, and lipid abnormalities, and bone disease as well as cardiovascular disease. With some exceptions for lipid management, these morbidities can be managed. This review aims at describing different non-hepatic adverse effects of antiretrovirals as well as factors associated with them
Serologic and Genotypic Characterization of Hepatitis B Virus in HIV-1 Infected Patients From South West and Littoral Regions of Cameroon
(Virology Journal, 2016) Magoro, Tshifhiwa; Gachara, George; Mavhandu, Lufuno; Lum, Emmaculate; Kimbi, Helen K.; Ndip, Roland N.; Bessong, Pascal
Background: HBV and HIV share similar transmission routes. Concurrent infection with the two viruses usually results in more severe and progressive liver disease, and a higher incidence of cirrhosis, liver cancer and mortality. Further, this co-infection may lead to cross-resistance between HIV and HBV drugs and increased liver injury, either due to direct hepatotoxicity or drug-related immune-reconstitution hepatitis. These challenges necessitate continuous surveillance for HBV among HIV infected individuals to guide patient management. We conducted this study to understand the serologic and genotypic characteristics of HBV among HIV/HBV infected patients in South West and Littoral Regions of Cameroon. Methods: Plasma samples were screened for HBsAg, HBeAg, Anti-HBs and anti-HBc using ELISA followed by DNA extraction from all HBsAg positive samples. A 366 bp region covering the overlapping surface/polymerase gene was amplified by a nested PCR and the product sequenced using Big Dye sequencing chemistry. The resulting sequences were then analyzed for genotypes and both escape and drug resistance mutations. Results: Of the 455 samples in this study, 25.5 % (n = 116) were HBsAg positive and 46 of these had their DNA successfully amplified. Genotype E was found in 32 samples (69.6 %) and genotype A in the rest of the samples. Escape mutations associated with failure of diagnosis (Y100C, R122K and Q129H) and with vaccine escape (Q129R and T131N) were detected in varying frequencies in the population. Polymerase mutations implicated in resistance to lamivudine and other ʟ-nucleoside analogues were detected in seven patients (15.2 %), while all the samples lacked mutations associated with resistance to adefovir and tenofovir. Conclusions: These findings suggest the endemicity of HBV and the predominance of genotypes A and E in the study population. Also, drug resistance findings support the use of tenofovir based ART regimens among HIV/HBV co-infected persons. There is need for continuous HBV screening and monitoring in HIV infected individuals in these regions. Keywords: Hepatitis B virus, HIV/HBV co-infection, HBV genotypes, Phylogenetic analysis
Oil Contents and Aflatoxin Levels in Peanuts Varieties Produced in Busia and Kisii Central Districts, Kenya
(OMICS International, 2016) Menza, Nelson C.; Muturi, Margaret W.; Kamau, Lucy M.
Busia and Kisii Central districts have repeatedly reported high levels of aflatoxins in foods. The objectives of the study were to determine oil contents and the relationship between oil contents and the levels of total aflatoxin in peanuts varieties produced in the two districts. Three samples of each of the four (4) varieties of peanuts obtained from Busia; Valencia red, Uganda local, Homa Bay local and local red and 3 varieties from Kisii Central; Valencia red, Uganda local and Homa Bay local were analyzed and the average oil contents of the samples in each variety determined. The oil contents of peanuts were determined by a standard Soxtec extraction method and total aflatoxins were analyzed using high performance liquid chromatography (HPLC) technique. Peanuts from Busia district had significantly higher oil contents compared to those from Kisii Central (t=3.22, df=6, P=0.012). Peanuts of Valencia red variety from both Busia and Kisii Central had higher oil content (mean 46.9), than other varieties. In addition, Valencia red from Busia district had slightly higher oil content (47.2%) than those of the same variety from Kisii Central (46.6%). However, the difference was not significant (t=1.08, df=6, P=0.394). Overall, oil content in peanuts decreased with an increase in aflatoxin levels (r=-0.496, P=0.031) except in peanuts of Uganda local red variety from Kisii Central. Growing of improved varieties of peanuts such as Valencia red which was least contaminated with aflatoxin and had higher oil content should be encouraged in Kenya
Serotype and Genetic Diversity of Human Rhinovirus Strains that Circulated in Kenya in 2008
(Wiley Open Access, 2016) Milanoi, Sylvia; Ongus, Juliette R.; Gachara, George; Coldren, Rodney; Bulimo, Wallace
Background: Human Rhinoviruses (HRVs) are a well-established cause of the common cold and recent studies indicated that they may be associated with severe acute respiratory illnesses (SARIs) like pneumonia, asthma and bronchiolitis. Despite global studies on the genetic diversity of the virus, the serotype diversity of these viruses across diverse geographical regions in Kenya has not been characterized. Objectives: This study sought to characterize the serotype diversity of HRV strains that circulated in Kenya in 2008. Methods: A total of 517 archived nasopharyngeal samples collected in a previous respiratory virus surveillance program across Kenya in 2008 were selected. Participants enrolled were outpatients who presented with influenza-like (ILI) symptoms. Real time RT-PCR was employed for preliminary HRV detection. HRV positive samples were amplified using RT-PCR and thereafter the nucleotide sequences of the amplicons were determined followed by phylogenetic analysis. Results: Twenty five percent of the samples tested positive for HRV. Phylogenetic analysis revealed that the Kenyan HRVs clustered into three main species comprising HRV A (54%), HRV-B (12%) and HRV C (35%). Overall, 20 different serotypes were identified. Intra-strain sequence homology among the Kenyan strains ranged from 58% to 100% at the nucleotide level and 55% to 100% at the amino acid level. Accepted Article This article is protected by copyright. All rights reserved. Conclusion: These results show that a wide range of HRV serotypes with different levels of nucleotide variation were present in Kenya. Furthermore, our data show that HRVs contributed substantially to influenza-like illness in Kenya in 2008.
Characterization of occult hepatitis B virus infection among HIV positive patients in Cameroon
(BioMed Central, 2017) Gachara, George; Magoro, Tshifhiwa; Mavhandu, Lufuno; Lum, Emmaculate; Kimbi, Helen K.; Ndip, Roland N.; Bessong, Pascal O.
Purpose: Occult hepatitis B infection (OBI) among HIV positive patients varies widely in different geographic regions. We undertook a study to determine the prevalence of occult hepatitis B infection among HIV infected individuals visiting a health facility in South West Cameroon and characterized occult HBV strains based on sequence analyses. Methods: Plasma samples (n = 337), which previously tested negative for hepatitis B surface antigen (HBsAg), were screened for antibodies against hepatitis B core (anti-HBc) and surface (anti-HBs) antigens followed by DNA extraction. A 366 bp region covering the overlapping surface/polymerase gene of HBV was then amplified in a nested PCR and the amplicons sequenced using Sanger sequencing. The resulting sequences were then analyzed for genotypes and for escape and drug resistance mutations. Results: Twenty samples were HBV DNA positive and were classified as OBI giving a prevalence of 5.9%. Out of these, 9 (45%) were anti-HBs positive, while 10 (52.6%) were anti-HBc positive. Additionally, 2 had dual anti-HBs and anti-HBc reactivity, while 6 had no detectable HBV antibodies. Out of the ten samples that were successfully sequenced, nine were classified as genotype E and one as genotype A. Three sequences possessed mutations associated with lamivudine resistance. We detected a number of mutations within the major hydrophilic region of the surface gene where most immune escape mutations occur. Conclusions: Findings from this study show the presence of hepatitis B in patients without any of the HBV serological markers. Further prospective studies are required to determine the risk factors and markers of OBI. Keywords: Hepatitis B virus, Occult hepatitis B infection, HIV, Cameroon
Occurrence of Aflatoxigenic Aspergillus Species in Various Varieties of Peanuts Produced in Western Kenya
(PrePrints, 2017) Menza, Nelson C.; Muturi, Margaret W.; Kamau, Lucy
Aflatoxin contaminates foods including peanuts. Aflatoxin is a carcinogenic toxin mainly produced bty Aspergillus flavus. Other Aspergillus species that rarely produce aflatoxins are A. nomius and A. niger. Aflatoxin is associated with liver failure, hepatocellular carcinoma (HCC) and death. Recent studies have shown that peanuts in Kenya are highly contaminated with aflatoxins but information gaps exist on the characterization of the Aspergillus species that produce aflatoxins in peanuts in Kenya. Therefore, this gap necessitated the determination of the Aspergillus species producing aflatoxins in peanuts from the main growing districts of Busia and Kisii Central districts. One hundred and two (102) peanuts samples were collected from farmers’ in each district Aspergillus species were isolated from the peanut samples by using the dilution plate technique on modified Rose Bengal agar. Phenotypical characterization of the identified Aspergillus section flavus isolates from the peanuts samples was determined using the procedure of Mellon and Cotty. This study identified five (5) Aspergillus species as contaminants in peanuts analyzed in this study. They were Aspergillus flavus L-strain, Aspergillus flavus S-strain, Aspergillus parasiticus, Aspergillus niger and Aspergillus tamari. Overall, the occurrence of Aspergillus flavus L- strain and A. flavus S- strain were significantly higher than other species identified (H = 15.55, df = 4, P = 0.004) in peanuts from the two districts. However, A. flavus Sstrain was the most dominant species identified in the study with a mean occurrence of 45.1%. Aspergillus flavus L- strain was the most common isolate (58.8%) in peanuts from Busia district while A. flavus S- strain was the most common strain (60.2%) in peanuts from Kisii Central district. Overall, the occurrence of Aspergillus flavus L strain and A. flavus S strain were significantly higher than other species identified (H = 15.55, df = 4, P = 0.004) in peanuts from the two districts. However, A. flavus S-strain was the most dominant species (F=3.15, df =25, P=0.031) with an overall mean occurrence of 45.1%. The confirmation of occurrence of other species that produce toxins such as A. niger and A. tamarii which also produces cyclopiazonic acid suggests the need to screen peanuts for other carcinogenic mycotoxins
Uropathogens Antibiotic Resistance Patterns Among Type 2 Diabetic Patients in Kisii Teaching and Referral Hospital, Kenya
(Pan African Medical Journal, 2018) Mageto, Vincent Mogaka; Gatwiri, Mathenge Scholastica; Njoroge, Wachuka
Introduction: Non-insulin dependent diabetes mellitus is a major risk factor for urinary tract infections. Irrational use of antibiotics has led to the emergency of uropathogens resistant to available antibiotics. The main objective was to determine the bacterial causative agents of urinary tract infections and their antibiotic resistance patterns. Methods: One hundred and eighty (180) type 2 diabetic patients were recruited to take part in the study. Urine samples were collected and cultured for urinary tract infections diagnosis and antibiotic sensitivity. Results: A total of 35 isolates were obtained from the study. All the isolates were sensitive to gentamicin. All 21 (100%) isolates of E. coli were sensitive to gentamicin and cephalexin. All 10 (100%) K. pneumoniaeisolates were sensitive to gentamicin and nitrofurantoin. Out of the 21 E. coli isolates, five of them showed resistance to ampicillin, three E. coli isolates showed resistance to nitrofurantoin and another three E. coliisolates showed resistance to cotrimoxazole. Out of 10 K. pneumoniae isolates, two of them were found to be resistant to ampicillin, one K. pneumoniae isolate was resistant to cephalexin and two K. pneumoniaeisolates were resistant to co-trimoxazole. Out of the four P. mirabilis isolates, there were three cases where one isolate was each resistant to ampicillin, nitrofurantoin and co-trimoxazole. Conclusion: There is a need to have a regular screening of bacterial isolates causing urinary tract infection in diabetic patients and their antibiotic sensitivity in order to have effective therapy. Present findings show that there is increased resistance to the commonly prescribed antibiotics
Socio-demographic and sexual practices associated with HIV infection in Kenyan injection and non-injection drug users
(BioMed Central, 2018) Budambula, Valentine; Matoka, Charles; Ouma, James; Ahmed, Aabid A.; Otieno, Michael F.; Were, Tom
Background: Substance use is increasingly becoming prevalent on the African continent, fueling the spread of HIV infection. Although socio-demographic factors influence substance consumption and risk of HIV infection, the association of these factors with HIV infection is poorly understood among substance users on the African continent. The objective of the study was to assess socio-demographic and sexual practices that are associated with HIV infection among injection drug users (IDUs), non-IDUs, and non-drug users (DUs) at an urban setting of coastal Kenya. Methods: A cross-sectional descriptive study was conducted among 451 adults comprising HIV-infected and -uninfected IDUs (n = 157 and 39); non-IDUs (n = 17 and 48); and non-DUs (n = 55 and 135); respectively at coastal, Kenya. Respondent driven sampling, snowball and makeshift methods were used to enroll IDUs and non-IDUs. Convenience and purposive sampling were used to enroll non-DUs from the hospital’s voluntary HIV testing unit. Participant assisted questionnaire was used in collecting socio-demographic data and sexual practices. Results: Binary logistic regression analysis indicated that higher likelihood of HIV infection was associated with sex for police protection (OR, 9.526; 95% CI, 1.156-78.528; P = 0.036) and history of sexually transmitted infection (OR, 5.117; 95% CI, 1.924-13.485; P = 0.001) in IDUs; divorced, separated or widowed marital status (OR, 6.315; 95% CI, 1.334-29.898; P = 0.020) in non-IDUs; and unemployment (OR, 2.724; 95% CI, 1.049-7.070; P = 0.040) in non-drug users. However, never married (single) marital status (OR, 0.140; 95% CI, 0.030-0.649; P = 0.012) was associated with lower odds for HIV infection in non-drug users. Conclusion: Altogether, these results suggest that socio-demographic and sexual risk factors for HIV transmission differ with drug use status, suggesting targeted preventive measures for drug users. Keywords: HIV infection, Injection drug users (IDUs), Non-IDUs, Non-drug users, Socio-demographic and sexual risk practices

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