RESUMEN
OBJECTIVE: To evaluate hepatitis B serological markers in pregnant women from various geographical sites in Kenya. DESIGN: A cross-sectional observational study of women attending antenatal clinics. SETTING: The Kenyatta National Hospital and eight hospitals from five provinces in Kenya. SUBJECTS: All women in their third trimester of pregnancy attending the antenatal clinic over the period June 2001 to June 2002. MAIN OUTCOME MEASURES: For each pregnant woman age and gestation were documented. Hepatitis serological markers were evaluated. RESULTS: A total of 2241 pregnant women were enrolled. Among them 205 women (9.3%) were positive for HbsAg and from these 18 (8.8%) were found to have HbeAg. Protective antibodies (anti-HbsAg) were detected in 669 (30.2%) of the women. There were notable significant regional differences for HbsAg rates. CONCLUSIONS: These results confirm the presence of high disease carrier rate and the corresponding previously reported low level of HbeAg suggesting questionable low rate of perinatal transmission but high rate of horizontal transmission.
Asunto(s)
Hepatitis B/epidemiología , Complicaciones Infecciosas del Embarazo/epidemiología , Adolescente , Adulto , Biomarcadores/sangre , Niño , Femenino , Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Humanos , Kenia/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/sangre , Estudios SeroepidemiológicosRESUMEN
An epidemiological study on the G serotype distribution of group A rotaviruses (GARV) isolated in Kenya was carried out in one urban hospital in Nairobi and in two rural hospitals in Nanyuki and Kitui to clarify the prevalent G serotypes before future introduction of the ready licensed rotavirus vaccine in Kenya. A total of 1,431 stool specimens were collected from children, who were mainly outpatients, aged from 0 to 6 years old with acute gastroenteritis from August 1991 to July 1994. Samples positive for GARV by conventional ELISA were then analyzed by subgrouping and serotyping ELISA and by PAGE. To ascertain the G serotypes of viruses in samples that were unable to be typed by serotyping ELISA, polymerase chain reaction was also attempted. The prevalence of GARV was 28.4% in the urban hospital, 22.5% in Nanyuki, and 13.7% in Kitui. Among rotavirus-positive samples, subgroup II rotaviruses were detected in 63.1%, and subgroup I rotaviruses were 25.9%. Serotype G4 was most prevalent, accounting for 41.6% followed by 23.3% of serotype G1, 17.0% of serotype G2, and serotype G3 was rarely isolated. Seven strains of serotype G8/P1B rotavirus was detected for the first time in Kenya by RT-PCR. Eleven specimens with an unusual composition of subgroup, serotype, and electropherotype were atypical GARV in which the P-serotype was P1A, P1B, or P2. Although uncommon GARV serotype G8/P1B and atypical GARV were detected, the four major GARV serotypes, G1 through G4, should be targeted at this moment for vaccination to control this diarrheal disease in Kenya. Continuous monitoring of the G- and P-serotype distribution of GARV should provide important information about the impact of rotavirus vaccination in Kenya.
Asunto(s)
Gastroenteritis/epidemiología , Infecciones por Rotavirus/epidemiología , Rotavirus/genética , Niño , Preescolar , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Heces/virología , Gastroenteritis/virología , Genoma Viral , Hospitales Rurales , Hospitales Urbanos , Humanos , Lactante , Recién Nacido , Kenia/epidemiología , Prevalencia , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rotavirus/clasificación , Infecciones por Rotavirus/virología , Serotipificación , Factores de TiempoRESUMEN
An epidemiological survey on human calicivirus (HuCV) infections and associated gastroenteritis in infants was conducted to clarify the prevalence of HuCV infections in infants and adults in Kenya. Enzyme immunoassays (EIAs) for three genogroups of HuCVs, Norwalk virus (NV), Mexico virus (MXV), and Sapporo virus (SV), were used to detect antigen or antibody. We tested 1,431 stool samples obtained from children younger than 6 years old with acute gastroenteritis who visited outpatient clinics in three districts in Kenya from August 1991 to July 1994. Thirty-two (2.2%) of these stool samples were positive for SV antigen. Only one (0.1%) of 1,186 samples was positive for NV antigen and none of 246 samples was positive for MXV antigen. One hundred ninety-three serum samples were tested for antibodies to NV and MXV, and 64 of them were examined for antibody to SV. The pattern of the age-related prevalence of serum antibody to NV was different from that of antibodies to MXV and SV. The acquisition of serum antibodies to HuCVs in the three genogroups appeared in early childhood, at about 1 to 2 years of age. The prevalence of serum antibody to NV was low (about 60%) throughout adulthood compared with a high prevalence of antibody (approximately 80 to 90%) to MXV and SV. These data indicate that infections with viruses in the three genogroups of HuCVs are common in Kenya, and immunological responses to NV may be different from those to MXV and SV. The EIAs for the detection of NV and MXV antigens appear to be quite specific for prototype NV and MXV strains, respectively, so that they can detect only a few strains of HuCVs related to them. Alternatively, NV and MXV caused less severe infections that did not bring children to the outpatient clinics for gastroenteritis in Kenya.
Asunto(s)
Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/virología , Caliciviridae/genética , Caliciviridae/inmunología , Adolescente , Adulto , Anticuerpos Antivirales/sangre , Antígenos Virales/aislamiento & purificación , Caliciviridae/clasificación , Infecciones por Caliciviridae/inmunología , Niño , Preescolar , Heces/virología , Gastroenteritis/epidemiología , Gastroenteritis/inmunología , Gastroenteritis/virología , Genotipo , Humanos , Técnicas para Inmunoenzimas , Lactante , Kenia/epidemiología , Persona de Mediana Edad , Epidemiología Molecular , Virus Norwalk/clasificación , Virus Norwalk/genética , Virus Norwalk/inmunología , Virulencia/genética , Virulencia/inmunologíaRESUMEN
Human rotavirus strains from Kenya, from children with gastroenteritis in an urban area (Nairobi) and three rural areas were characterized by antigenic and genomic analysis. While in all areas strains with subgroups II and G serotype 1 antigens were most common, two unusual strains were detected. One strain (NK59: subgroup II, G serotype 4) possessed an additional RNA band on polyacrylamide gel electrophoresis, the other (D202) which had antigenic specificity of subgroup II and G serotype 1 showed a 'short' RNA pattern. The latter strain was adapted to growth in cell culture.
Asunto(s)
Gastroenteritis/microbiología , Infecciones por Rotavirus/microbiología , Rotavirus/clasificación , Anticuerpos Monoclonales , Antígenos Virales/análisis , Niño , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Heces/microbiología , Genes Virales/genética , Genotipo , Humanos , Kenia/epidemiología , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Rotavirus/genética , Rotavirus/inmunología , Infecciones por Rotavirus/epidemiología , Cultivo de VirusRESUMEN
Three hundred and three children under 5 years old with acute measles and diarrhoea (cases) and 300 other age-matched children with diarrhoea (controls) were examined for enteroadherent E. coli (EAEC) and other agents including rotavirus and Cryptosporidium. EAEC was determined by tissue culture of HEP-2 cells. Other agents were determined by conventional methods. EAEC was identified from both cases and control accounting for 10.3% (31/303) and 15.2% (46/300) respectively. Other bacterial agents were: 10.3% (31/303) from cases and 12.8% (39/300) from controls. A higher detection rate of enteroparasites was found among cases 15% (45/300) than controls 8.9% (27/300) whereas rotavirus was the reverse, 3% (9/303) in cases and 30.3% (92/300) in controls. To our knowledge characterization of EAEC has not been done before and therefore might be attributing factor to some of our unexplained diarrhoeal cases.
Asunto(s)
Diarrea/etiología , Infecciones por Escherichia coli/complicaciones , Escherichia coli/clasificación , Sarampión/complicaciones , Preescolar , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Hospitales Públicos , Humanos , Lactante , Recién Nacido , Kenia/epidemiología , Pruebas de Sensibilidad Microbiana , Prevalencia , SerotipificaciónRESUMEN
This pilot study was done in preparation to assist in chosing the appropriat site for a 5-year main study. The study aim was to find the differences in epidemiology of rotavirus (RV) and other viral agents causing gastroenteritits in children in Kenya between an urban hospital; in this case Kenyatta National Hospital; and a rural hospital to be chosen from Narok; Nanyuki or Kitui district hospitals. Stool specimens were collected for two weeks during the same period from children aged 0 to 14 years attending outpatient clinics and those admitted with diarrhoea at the hospitals. Stool specimens were subsequently analysed by the ELISA method. The presence of RV was confirmed by the sodium dodecyl sulphate polyacrylamide gel electrophoresis method which demonstrates the electrophoretic pattern of the RNA genome. The RV positive rates were 35 (21 in 60) in Nanyuki; 13.8 (4 in 29) in Narok and 1.8 (1 in 56) in Kitui. From these 26 RV strains; 8 (7 long and one short) electropherotype patterns were demonstrated. Subgrupingand serotyping was also done by ELISA method on the 26 isolates yielding 2 subgroup I and 24 subgroup II. The major serotypes were 1(30.8) and 4(26.9) while serotypes were undeterminable in 10 positive specimens. Tissue culture using MA104 cells yielded 5 strains from these positive specimens