32 research outputs found
Human caliciviruses detected in HIV-seropositive children in Kenya
The human caliciviruses (HuCVs) are important causes of gastroenteritis worldwide. Norovirus (NoV) and sapovirus (SaV) have been detected in HIV-seropositive children but the genetic diversity of HuCVs circulating in these individuals is largely unknown. In this study the prevalence and genotype diversity of HuCVs circulating in Kenyan HIV-positive children, with or without diarrhea, from the year 1999 to 2000 was investigated. The overall prevalence of HuCVs was 19% with NoV predominating at 17% (18/105) and SaV present in 5.7% (6/105) of specimens. Human CVs were detected in both symptomatic (24%) and asymptomatic (16%) children. Co-infections with other enteric viruses were detected in 21.6% of children with diarrhea but only in 4.4% of children without diarrhea. Remarkable genetic diversity was observed with 12 genotypes (7 NoV, 5 SaV) being identified in 20 HuCV-infected children. NoV genogroup II (GII) strains predominated with GII.2 and GII.4 each representing 27% of the NoV-positive strains. The GII.4 strain was most closely related to the nonepidemic GII.4 Kaiso 2003 variant. Other NoV genotypes detected were GI.3, GII.6, GII.12, GII.14, and GII.17. Five different SaV genotypes (GI.2, GI.6, GII.1, GII.2, and GII.4) were characterized from six specimens. Diarrheal symptoms were not associated with any specific HuCV genotype. Overall the HuCV genotype distribution detected in this study reflects those in other studies worldwide. The strains detected are closely related to genotypes that have circulated on several continents since the year 2000.Poliomyelitis Research Foundation (PRF)of SA for research funding (Grant number 09/33). TY Murray was supported by a PhD fellowship from the PRF and acknowledges a PhD bursary from the National Research Foundation of South Africa (NRF). J Mans was supported by a postdoctoral fellowship from the University of Pretoria. This work is based on research supported in part by the NRF (77655).
supported in part by the NRF (77655).http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1096-9071/hb201
Prevalence of enteropathogenic viruses and molecular characterization of group A rotavirus among children with diarrhea in Dar es Salaam Tanzania
Different groups of viruses have been shown to be responsible for acute diarrhea among children during their first few years of life. Epidemiological knowledge of viral agents is critical for the development of effective preventive measures, including vaccines. In this study we determined the prevalence of the four major enteropathogenic viruses - rotavirus, norovirus, adenovirus and astrovirus - was determined in 270 stool samples collected from children aged 0 - 60 months who were admitted with diarrhea in four hospitals in Dar es Salaam, Tanzania, using commercially available ELISA kits. In addition, the molecular epidemiology of group A rotavirus was investigated using reverse transcriptase multiplex polymerase chain reaction (RT-PCR). At least one viral agent was detected in 87/270 (32.2%) of the children. The prevalence of rotavirus, norovirus, adenovirus and astrovirus was 18.1%, 13.7%, 2.6% and 0.4%, respectively. In most cases (62.1%) of viruses were detected in children aged 7-12 months. The G and P types (VP7 and VP4 genotypes respectively) were further investigated in 49 rotavirus ELISA positive samples. G9 was the predominant G type (81.6%), followed by G1 (10.2%) and G3 (0.2%). P[8] was the predominant P type (83.7%), followed by P[6] (0.4%) and P[4] (0.2%). The following G and P types were not detected in this study population; G2, G4, G8 G10, P[9], P[10] and P[11]. The dominating G/P combination was G9P[8], accounting for 39 (90.7%) of the 43 fully characterized strains. Three (6.1%) of the 49 rotavirus strains could not be typed. Nearly one third of children with diarrhea admitted to hospitals in Dar es Salaam had one of the four viral agents. The predominance of rotavirus serotype G9 may have implication for rotavirus vaccination in Tanzania
Molecular characterization of rotavirus genotypes circulating in the eastern region of Kenya: Predominance of G9 and emergence of G12 genotypes
Molecular characterization of rotavirus genotypes circulating in the eastern region of Kenya: Predominance of G9 and emergence of G12 genotypes
Clinical Features Associated with Group A Rotavirus in Children Presenting with Acute Diarrhoea at Kenyatta National Hospital, Nairobi, Kenya
Background: Worldwide rotavirus (RV) infection is a major cause of diarrhea in children \u3c5 years of age. Continual monitoring of RV prevalenceand its associated clinical characteristics is necessary to estimate the burden of the disease. In this study, we evaluated the clinical featuresassociated with RV diarrhea such as dehydration and levels of electrolytes, urea and creatinine at Kenyatta National Hospital, Nairobi, Kenya.Methods: A total of 192 diarrheic stool samples were collected from children under 5 years of age and tested for presence of RV using enzymeimmunoassay (EIA). A further 92 blood samples collected from the same cohort but only targeting severely dehydrated children, were used for theanalysis of electrolytes (Potassium and Sodium ions), urea and creatinine.Results: Rotavirus was detected in 53.4% (103/192) of stool specimens. Dehydration was common in most of the children who presented withdiarrhea regardless of RV status (172/192; 89.6%). However, RV patients had increased duration and frequency of vomiting compared with nonrotavirus patients but levels of dehydration were similar in both groups. There was loss of electrolytes and elevated levels of both urea (\u3e7.5mmol/l)and creatinine (\u3e80μmol/l) in all severely dehydrated cases.Conclusion: Rotavirus was associated with increased duration and frequency of vomiting, but loss of electrolytes and elevated levels of bothurea and creatinine were similar among severely dehydrated RV positive and negative children. This study provides useful information to policymakers on RV that could, together with other studies in Kenya on RV, aid in understanding the disease burden, earlier clinical diagnosis andevaluation of cost benefit analysis for RV vaccines in Keny
Evidence of a Recombinant Wild-Type Human Astrovirus Strain from a Kenyan Child with Gastroenteritis▿
A human astrovirus (HAstV) strain from Kenya was characterized by nucleotide sequence analysis. Sequences from open reading frame 1a (ORF1a) clustered with genotype 6/7, those from ORF1b clustered with genotype 3, and those from ORF2 clustered with genotype 2. A recombination point in the ORF1b-ORF2 junction was identified, with a second possible recombination point within the ORF1a region
High prevalence of species D human adenoviruses in fecal specimens from Urban Kenyan children with diarrhea
Cyclospora papionis, Cryptosporidium hominis, and Human-Pathogenic Enterocytozoon bieneusi in Captive Baboons in Kenya▿
Cyclospora papionis, Cryptosporidium hominis, and Enterocytozoon bieneusi were detected in 42 (17.9%), 6 (2.6%), and 29 (12.3%) of 235 newly captured baboons in Kenya, respectively. Most C. hominis subtypes and E. bieneusi genotypes found have been detected in humans in the area, suggesting that cross-species transmission of cryptosporidiosis and microsporidiosis is possible
Genotype Distribution of Human Sapoviruses in Wastewater in Japan▿
Human sapovirus sequences were identified in 12 (100%) influent and 7 (58%) effluent wastewater samples collected once a month for a year. The strains were characterized based on their partial capsid gene sequences and classified into 10 genotypes, demonstrating that genetically diverse sapovirus strains infect humans in the study area