RESUMO
Rotaviruses are the main cause of infantile acute diarrhea, and a monovalent (G1P[8]) vaccine against the virus was introduced into the Brazilian National Immunization Program for all infants in March 2006. The objectives of this study were to determine the rate and genotype distribution of rotavirus causing infantile diarrhea in the Triângulo Mineiro region of Brazil during 2011-2012 and to assess the impact of local vaccination. Fecal specimens were analyzed for detection and characterization of rotavirus using polyacrylamide gel electrophoresis, reverse transcription followed by polymerase chain reaction (PCR), and PCR-genotyping assays. Overall, rotavirus was diagnosed in 1.7% (6/348) of cases. Rotavirus positivity rates decreased 88% [95% confidence intervals (CI)=15.2, 98.3%; P=0.026] in 2011 and 78% (95%CI=30.6, 93.0%; P=0.007) in 2012 when compared with available data for baseline years (2005/2006) in Uberaba. In Uberlândia, reductions of 95.3% (95%CI=66.0, 99.4%; P=0.002) in 2011, and 94.2% (95%CI=56.4, 99.2%; P=0.004) in 2012 were also observed compared with data for 2008. The circulation of rotavirus G2P[4] strains decreased during the period under study, and strains related to the P[8] genotype reemerged in the region. This study showed a marked and sustained reduction of rotavirus-related cases, with a lack of rotavirus in the 2011 and 2012 seasons, suggesting a positive impact of the vaccination program.
Assuntos
Criança , Pré-Escolar , Humanos , Lactente , Diarreia Infantil/virologia , Infecções por Rotavirus/epidemiologia , Rotavirus/genética , Brasil/epidemiologia , Diarreia Infantil/epidemiologia , Monitoramento Epidemiológico , Fezes/microbiologia , Genótipo , Técnicas de Genotipagem , Programas de Imunização/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Infecções por Rotavirus/prevenção & controle , Rotavirus/classificação , Estações do AnoRESUMO
Rotaviruses are the main cause of infantile acute diarrhea, and a monovalent (G1P[8]) vaccine against the virus was introduced into the Brazilian National Immunization Program for all infants in March 2006. The objectives of this study were to determine the rate and genotype distribution of rotavirus causing infantile diarrhea in the Triângulo Mineiro region of Brazil during 2011-2012 and to assess the impact of local vaccination. Fecal specimens were analyzed for detection and characterization of rotavirus using polyacrylamide gel electrophoresis, reverse transcription followed by polymerase chain reaction (PCR), and PCR-genotyping assays. Overall, rotavirus was diagnosed in 1.7% (6/348) of cases. Rotavirus positivity rates decreased 88% [95% confidence intervals (CI)=15.2, 98.3%; P=0.026] in 2011 and 78% (95%CI=30.6, 93.0%; P=0.007) in 2012 when compared with available data for baseline years (2005/2006) in Uberaba. In Uberlândia, reductions of 95.3% (95%CI=66.0, 99.4%; P=0.002) in 2011, and 94.2% (95%CI=56.4, 99.2%; P=0.004) in 2012 were also observed compared with data for 2008. The circulation of rotavirus G2P[4] strains decreased during the period under study, and strains related to the P[8] genotype reemerged in the region. This study showed a marked and sustained reduction of rotavirus-related cases, with a lack of rotavirus in the 2011 and 2012 seasons, suggesting a positive impact of the vaccination program.
Assuntos
Diarreia Infantil/virologia , Infecções por Rotavirus/epidemiologia , Rotavirus/genética , Brasil/epidemiologia , Criança , Pré-Escolar , Diarreia Infantil/epidemiologia , Monitoramento Epidemiológico , Fezes/microbiologia , Genótipo , Técnicas de Genotipagem , Humanos , Programas de Imunização/estatística & dados numéricos , Lactente , Pacientes Ambulatoriais/estatística & dados numéricos , Rotavirus/classificação , Infecções por Rotavirus/prevenção & controle , Estações do AnoRESUMO
BACKGROUND: Rotaviruses are the major cause of diarrhea in children for which a monovalent G1P[8] vaccine has been provided free for all Brazilian infants since March 2006. OBJECTIVES: To investigate prevalence and genotypes of rotavirus strains causing diarrhea in children in Triângulo Mineiro, Minas Gerais, during 2007-2010, and to assess local vaccine impact. STUDY DESIGN: Fecal specimens were analyzed for rotavirus detection and characterization by PAGE, RT-PCR and PCR-genotyping assays. RESULTS: Overall, rotavirus was diagnosed in 12.1% (76/630) cases, accounting for 35.8% of the hospitalizations and 6.5% of outpatient attendance due to diarrhea. A trend in rotavirus disease reduction occurred in both cities (71.8% and 83.4% in Uberaba; 95.3% in Uberlândia) up to 2009, but it reversed in 2010 with increased rotavirus cases in Uberlândia. Short pattern G2P[4] strains were detected in all but three (96%) cases of mixed/P[NT] infections with long electropherotypes. CONCLUSIONS: This 4-year follow-up study showed a reduction in rotavirus-related diarrhea and even skipped a rotavirus season, which is consistent with vaccine mediated protection. The 2007-2010 rotavirus epidemic curve reflected the natural cyclic fluctuation of the single G2P[4] genotype, with sharp reduction of cases in 2008 leading to lack of a rotavirus 2009 season (both cases and hospitalizations) followed by its come back in 2010. Diarrhea cases related to either vaccine serotype/genotype (G1 or P[8]) were not detected. Thus, a new scenario emerged with a single epidemic genotype replacing the cocirculation of great diversity of genotypes, thus far, a hallmark of the epidemiology of rotavirus in Brazil.
Assuntos
Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/administração & dosagem , Rotavirus/genética , Brasil/epidemiologia , Criança , Pré-Escolar , Diarreia/virologia , Fezes/virologia , Seguimentos , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Infecções por Rotavirus/epidemiologiaRESUMO
BACKGROUND: Rotaviruses are major causes of diarrhea in children for which vaccines were developed and are currently in use. OBJECTIVES: To investigate the genotypes of rotavirus strains causing dehydrating diarrhea in children in Uberaba, Triângulo Mineiro region, Minas Gerais, during 2005-2006. METHODS: Rotavirus-associated diarrhea was investigated in fecal specimens by PAGE and strains were characterized for their genotype by RT-PCR and PCR-typing assays. RESULTS: Rotavirus was detected in 15% (39/260) of the fecal specimens by PAGE: 64% of the specimens presented short electrophoretic patterns and G2P[4] genotype; and 36% presented long electropherotypes and G1P[8], G9P[8], G4P[9] and two strains with sill undetermined G and P[8] genotype. A change in the dominant electrophoretic pattern was observed, shifting from long to short patterns and coinciding with the highest incidence of diarrheal cases. CONCLUSIONS: Those are the first data on rotavirus strains circulating in the Triângulo Mineiro region. They were obtained over a 16-month period that included the first 10 months after the launch of the national rotavirus immunization program that uses a monovalent G1P[8] attenuated vaccine strain. These results should further our understanding of the dynamics of rotavirus strains and help interpreting the significance of the program.
Assuntos
Diarreia/epidemiologia , Diarreia/virologia , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/imunologia , Rotavirus/classificação , Rotavirus/isolamento & purificação , Brasil/epidemiologia , Pré-Escolar , Eletroforese em Gel de Poliacrilamida , Fezes/virologia , Genótipo , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/genéticaRESUMO
Given the loss of therapeutic efficacy associated with the development of resistance to lamivudine (LMV) and the availability of new alternative treatments for chronic hepatitis B patients, early detection of viral genotypic resistance could allow the clinician to consider therapy modification before viral breakthrough and biochemical relapse occur. To this end, 28 LMV-treated patients (44 ± 12 years; 24 men), on their first therapy schedule, were monitored monthly at four Brazilian centers for the emergence of drug resistance using the reverse hybridization-based INNO-LiPA HBV DR assay and occasionally sequencing (two cases). Positive viral responses (HBV DNA clearance) after 6, 12, and 18 months of therapy were achieved by 57, 68, and 53 percent of patients, while biochemical responses (serum alanine aminotransferase normalization) were observed in 82, 82, and 53 percent of cases. All viral breakthrough cases (N = 8) were related to the emergence of YMDD variants observed in 7, 21, and 35 percent of patients at 6, 12, and 18 months, respectively. The emergence of these variants was not associated with viral genotype, HBeAg expression status, or pretreatment serum alanine aminotransferase levels. The detection of resistance-associated mutations was observed before the corresponding biochemical flare (41 ± 14 and 60 ± 15 weeks) in the same individuals. Then, if highly sensitive LMV drug resistance testing is carried out at frequent and regular intervals, the relatively long period (19 ± 2 weeks) between the emergence of viral resistance and the onset of biochemical relapse can provide clinicians with ample time to re-evaluate drug therapy.
Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivos de Aminoácidos/genética , Farmacorresistência Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Alanina Transaminase/sangue , DNA Viral/sangue , Seguimentos , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Mutação/genética , Reação em Cadeia da Polimerase , Estudos ProspectivosRESUMO
Given the loss of therapeutic efficacy associated with the development of resistance to lamivudine (LMV) and the availability of new alternative treatments for chronic hepatitis B patients, early detection of viral genotypic resistance could allow the clinician to consider therapy modification before viral breakthrough and biochemical relapse occur. To this end, 28 LMV-treated patients (44 +/- 12 years; 24 men), on their first therapy schedule, were monitored monthly at four Brazilian centers for the emergence of drug resistance using the reverse hybridization-based INNO-LiPA HBV DR assay and occasionally sequencing (two cases). Positive viral responses (HBV DNA clearance) after 6, 12, and 18 months of therapy were achieved by 57, 68, and 53% of patients, while biochemical responses (serum alanine aminotransferase normalization) were observed in 82, 82, and 53% of cases. All viral breakthrough cases (N = 8) were related to the emergence of YMDD variants observed in 7, 21, and 35% of patients at 6, 12, and 18 months, respectively. The emergence of these variants was not associated with viral genotype, HBeAg expression status, or pretreatment serum alanine aminotransferase levels. The detection of resistance-associated mutations was observed before the corresponding biochemical flare (41 +/- 14 and 60 +/- 15 weeks) in the same individuals. Then, if highly sensitive LMV drug resistance testing is carried out at frequent and regular intervals, the relatively long period (19 +/- 2 weeks) between the emergence of viral resistance and the onset of biochemical relapse can provide clinicians with ample time to re-evaluate drug therapy.
Assuntos
Motivos de Aminoácidos/genética , Farmacorresistência Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Idoso , Alanina Transaminase/sangue , DNA Viral/sangue , Feminino , Seguimentos , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Reação em Cadeia da Polimerase , Estudos ProspectivosRESUMO
In the fall of 1995, within a month of deployment to Haiti for peacekeeping duty, four Bangladeshi soldiers developed acute icteric hepatitis in rapid succession. Hepatitis E virus (HEV) was found to be the etiology by demonstrating HEV genomic sequences in serum samples by the polymerase chain reaction (PCR) and serologically by the detection of elevated IgM titers to HEV. No case had serologic evidence of acute hepatitis A or C infection. The soldiers had probably acquired their infection while living in a cantonment area outside Dhaka, Bangladesh for one month prior to deployment. Cloning and sequencing of amplified PCR products demonstrated a single strain suggestive of a common source of infection. Furthermore, high genomic identity with Asian strains of HEV and dissimilarity with the Mexican strain was demonstrated, verifying that the strain had indeed been imported. Human waste management from the Bangladesh camp in Haiti was strictly controlled and no secondary cases were observed. A convenience sample of 105 (12%) soldiers from the Bangladesh battalion (850 men) revealed anicteric or asymptomatic HEV infection in seven (7%) of 105. This report contains the first demonstration of acute hepatitis E in natives of Bangladesh and demonstrates the power of the PCR in the rapid diagnosis and epidemiologic analysis of HEV infection. More importantly, this cluster demonstrates the importation of an important infectious disease by multinational peacekeepers to a potentially susceptible host country.
Assuntos
Hepatite E/epidemiologia , Militares , Doença Aguda , Bangladesh/etnologia , Haiti/epidemiologia , Hepatite E/genética , Hepatite E/imunologia , Vírus da Hepatite E/genética , Vírus da Hepatite E/imunologia , Humanos , Masculino , RNA Viral/genética , Conglomerados Espaço-Temporais , ViagemRESUMO
Evidência sorológica de infecçäo por rotavírus em uma colônia de cobaios - Anticorpos reagindo com rotavírus símio SA11 foram demonstrados por ensaio imuno-enzimático (EIE) e por "Western blot assay" (WBA) em soros de cobaios mantidos para fins experimentais na Fundaçäo Oswaldo Cruz, Rio de Janeiro, Brasil. A proporçäo de animais soro-positivos e os níveis de anticorpos subiram rapidametne em 1985, mantiveram-se altos em 1986 e baixaram em 1987. Näo foram observados sinais de doença coincidente com a elevaçäo de anticorpos. Resultados de WBA sugerem que o rotavírus responsável pela resposta sorológica pertence ao subgrupo do grupo A
Assuntos
Cobaias , Animais , Anticorpos Antivirais/análise , Rotavirus/imunologia , Suscetibilidade a Doenças , Técnicas ImunoenzimáticasRESUMO
Antibodies reacting with simian rotavirus SA11 were detected by enzyme immunoassay (EIA) and Western blot assay (WBA) in sera from guinea pigs bred for experimental use at the Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. The proportion of antibody-positive animals and the antibody titres rose sharply in 1985, were maintained at a high levels in 1986 and declined in 1987. There were no obvious signs of disease coinciding with serological evidence of infection. Results of WBA suggest that the virus involved belongs to subgroup 1 of group A rotaviruses.
Assuntos
Anticorpos Antivirais/análise , Infecções por Rotavirus/diagnóstico , Rotavirus/imunologia , Animais , Western Blotting , Cobaias , Técnicas ImunoenzimáticasRESUMO
A combined enzyme immunoassay using nitrocellulose membrane as solid support is described for the detection of rotavirus and adenovirus in faeces from children with gastroenteritis. Its sensitivity and specificity are comparable to those of a previously described assay performed on plastic microplates (Pereira et al. (1985) J. Virol. Methods 10, 21-28). The introduction of nitrocellulose membrane as support for the immune reactions greatly simplifies the multiple washing steps and precludes the need for disposable plastic plates.