Acute hemorrhagic conjunctivitis epidemic in São Paulo State, Brazil, 2011

Acute hemorrhagic conjunctivitis (AHC) infection is highly contagious and can lead to explosive epidemics. In early February 2011, the Center for Epidemiologic Surveillance of the State of São Paulo Health Secretariat (SES-SP) in Brazil received reports of conjunctivitis outbreaks from rural areas of the state that subsequently spread statewide. This report describes that AHC epidemic and its etiologic agent. Data from the Ministry of Health Information System for Notifiable Diseases (SinanNet) and the SES-SP epidemiologic surveillance system for conjunctivitis, developed to detect outbreaks, confirm the etiologic agent, and carry out control measures, were analyzed. Eye (conjunctival swab) samples were taken from patients with clinical presentation of viral conjunctivitis to perform viral laboratory diagnosis. A total of 1 067 981 conjunctivitis cases were reported to the surveillance system for 2011; there was an increase in the number of cases in epidemiologic weeks 6­26 (summer season) versus previous years. Most cases occurred in the metropolitan region of Greater São Paulo. Of 93 collected samples, 57 tested positive for coxsackievirus-A24 (CV-A24), based on virus isolation in tissue-culture cell lines, reverse transcription polymerase chain reaction (RT-PCR), and enterovirus sequencing of RT-PCR. The data analysis showed that the fast-spreading etiologic agent of the AHC epidemic that occurred in the summer of 2011 was CV-A24. The AHC epidemic was due to an enterovirus that occurred sporadically, spread rapidly and with great magnitude, and had substantial socioeconomic impact due to the high level of absenteeism at work and school.

Rotavirus genotypes and the indigenous children of Brazilian midwest in the vaccine era, 2008-2012: footprints of animal genome

World group A rotavirus (RVA) surveillance data provides useful estimates of the disease burden, however, indigenous population might require special consideration. The aim of this study was to describe the results of G­ and P­types from Brazilian native children ≤3 years. Furthermore, selected strains have been analyzed for the VP7, VP6, VP4, and NSP4 encoding genes in order to gain insight into genetic variability of Brazilian strains. A total of 149 samples, collected during 2008­2012, were tested for RVA using ELISA and PAGE, following by RT­PCR and sequencing. RVA infection was detected in 8.7% of samples (13/149). Genotype G2P[4] was detected in 2008 and 2010, G8P[6] in 2009, and G3P[8] in 2011. The phylogenetic analysis of the VP7 and VP4 genes grouped the Brazilian G2P[4] and G3P[8] strains within the lineages currently circulating in humans worldwide. However, the phylogenetic analysis of the VP6 and NSP4 from the Brazilian G2P[4] strains, and the VP7 and NSP4 from the Brazilian G3P[8] strains suggest a distant common ancestor with different animal strains (bovine, caprine, and porcine). The epidemiological and genetic information obtained in the present study is expected to provide an updated understanding of RVA genotypes circulating in the native infant population, and to formulate policies for the use of RVA vaccines in indigenous Brazilian people. Moreover, these results highlight the great diversity of human RVA strains circulating in Brazil, and an in­depth surveillance of human and animal RVA will lead to a better understanding of the complex dynamics of RVA evolution

Caracterização molecular de cepas de rotavírus e norovírus: um estudo de 6 anos (2004-2009) / Characterization of rotavirus and norovirus strains: a 6-year study (2004-2009)

OBJETIVO: Monitorar infecções causadas por rotavírus (RV) e norovírus (NoV) em crianças hospitalizadas < 5 anos com gastroenterite aguda provenientes do estado de São Paulo durante um período de 6 anos (2004-2009). MÉTODOS: Este estudo retrospectivo foi realizado em 61 centros médicos, utilizando amostras fecais coletadas por conveniência, analisadas por ensaio imunoenzimático, eletroforese em gel de poliacrilamida, transcrição reversa seguida de reação em cadeia pela polimerase e sequenciamento para caracterização dos genótipos. RESULTADOS: Infecções por RV e NoV foram detectadas em 29,6 por cento (144/487) e 29,2 por cento (26/89) das amostras, respectivamente. Os genótipos de RV detectados com maior frequência foram: G9P[8] em 2004; G1P[8] em 2005; G9P[8] em 2006; e G2P[4] durante os anos de 2007, 2008 e 2009. A taxa de detecção diminuiu de 36,3 por cento (33/91) em 2004 para 4,2 por cento (4/95) em 2009. NoV pertencente ao genogrupo GII foi encontrado em 61,6 por cento (16/26) das amostras, e GI em 11,5 por cento (3/26). Infecções mistas por NoV e RV foram observadas em 2,2 por cento (2/89) das amostras, envolvendo as cepas GI+G9P[8] e GI+G2P[4]. CONCLUSÕES: A distribuição dos genótipos de RV variou com os anos, acompanhada pela redução no número de casos detectados. Ė necessário intensificar a vigilância pós-implantação da vacina contra RV, visando monitorar as cepas circulantes e sua eficácia contra possíveis genótipos emergentes. Os NoVs têm sido cada vez mais identificados como agentes etiológicos relevantes entre crianças hospitalizadas e exercem um papel importante na etiologia viral da gastroenterite pediátrica aguda no estado de São Paulo.

OBJECTIVE: To monitor rotavirus (RV) and norovirus (NoV) infections in hospitalized children < 5 years with acute gastroenteritis in the state of São Paulo, Brazil, during a 6-year period (2004- 2009). METHODS: This retrospective study was conducted with 61 medical centers with convenient surveillance fecal specimens, investigated by enzyme-linked immunosorbent assay, sodium dodecyl sulfate polyacrylamide gel electrophoresis, reverse polymerase chain reaction and sequencing to genotype characterization. RESULTS: RV and NoV infections were detected in 29.6 percent (144∕487) and 29.2 percent (26/89) of the samples, respectively. The most frequent RV genotypes detected were G9P[8] in 2004; G1P[8] in 2005; G9P[8] in 2006; and G2P[4] during 2007, 2008, and 2009. Detection rate declined from 36.3 percent (33∕91) in 2004 to 4.2 percent (4/95) in 2009. NoV genogroup GII was found in 61.6 percent (16/26) of the samples, and GI in 11.5 percent (3/26). Mixed NoV-RV infections were observed in 2.2 percent (2/89) of the samples, involving GI+G9P[8] and GI+G2P[4] strains. CONCLUSIONS: Genotype distribution varied according to collection year, accompanied by a reduction in detection rate. Use of RV vaccine requires implementation of post-marketing surveillance to monitor RV strain diversity and its efficacy against possible new emerging genotypes. NoVs have been increasingly identified as relevant etiological agents among hospitalized children and play an important role in the viral etiology of pediatric acute gastroenteritis in the state of São Paulo.

Evaluation of enterovirus 71 immune status in São Paulo state, Brazil / Avaliação da situação imunitária contra enterovírus 71 no estado de São Paulo, Brasil

Antibodies to Enterovirus 71 (EV71) were evaluated in São Paulo State during 1999-2005. The titer of neutralizing antibodies against EV71 was determined by microneutralization assay, and a titer of > 1:8 was defined as indicative of protected immunity. Neutralizing antibodies to EV71 were observed in 12.4 percent (55/442) of sera samples, a low protective rate, suggesting that EV71 infection is uncommon in this region, but that there is a relatively high susceptibility to EV71 related diseases, which is worrying considering the recent Asian outbreaks. Also, a significant location-specific difference in seropositivity was observed. Neutralizing antibodies to EV71 were observed in 8.7 percent (21/241) of São Paulo metropolitan area sera samples, and 16.9 percent (34/201) of the sera samples from other municipalities. A high number of Brazilian residents live in country and coastal areas without adequate access to piped water or sanitation. This situation may contribute to the EV71 dissemination in these zones. The analysis of environmental samples could possibly make a valuable contribution to studies on the epidemiology of EV71.

Anticorpos para Enterovírus 71 (EV71) foram avaliados no Estado de São Paulo durante 1999-2005. O título de anticorpos neutralizantes contra EV71 foi determinado pelo ensaio microneutralização, e um título de > 1:8 foi definido como indicador de imunidade protetora. Anticorpos neutralizantes para EV71 foram observados em 12,4 por cento (55/442) das amostras de soro, uma baixa taxa de proteção, sugerindo que a infecção pelo EV71 é incomum nesta região e que existe alta susceptibilidade a doenças relacionadas ao EV71, o que é preocupante considerando os recentes surtos asiáticos. Ainda, foi observada diferença significativa na soropositividade em relação à localização, onde 8,7 por cento (21/241) e 16,9 por cento (34/201) das amostras provenientes da região metropolitana de São Paulo, e demais municípios, respectivamente, apresentaram anticorpos neutralizantes para EV71. Um grande número de brasileiros vive em áreas rurais e à beira-mar, sem acesso adequado à água encanada ou saneamento. Essa situação pode contribuir para a disseminação de EV71 nessas regiões. A análise de amostras ambientais poderia gerar contribuição valiosa para estudos sobre a epidemiologia da EV71.

Caracterização de genótipos de rotavírus em creches: era pré e pós-vacinação contra o rotavírus / Characterization of rotavirus strains from day care centers: pre-and post-rotavirus vaccine era

OBJETIVOS: Em 2006, a vacina contra rotavírus foi incluída no Programa Nacional de Imunização. Este estudo teve como objetivo analisar os resultados da vigilância de genótipos de rotavírus em crianças < 5 anos com gastrenterites agudas provenientes de creches no estado de São Paulo por um período de 5 anos. MÉTODOS: Este estudo retrospectivo foi realizado em 30 creches no período de 2004 a 2008, com amostras fecais convenientes da vigilância das diarreias agudas, analisadas por ELISA, SDS-PAGE, RT-PCR e sequenciamento genético para caracterização do genótipo. RESULTADOS: Infecções por rotavírus foram detectadas em 28,3 por cento de amostras (38/134). Os genótipos mais frequentes detectados foram: G9P[8] e G1P[8] em 2004; G1P[8] em 2005; GNTP[NT] em 2006; G2P[4] em 2007; e nenhum caso foi relatado em 2008. Infecções mistas não foram observadas. A taxa de detecção diminuiu de 65,7 por cento (23/35) em 2004 para 50 por cento (9/18) em 2007. CONCLUSÕES: A distribuição do genótipo variou de acordo com os anos, acompanhada pela redução no número de casos detectados. É necessário intensificar a vigilância pós-implantação da vacina contra rotavírus, visando monitorar as linhagens circulantes e sua eficácia contra possíveis genótipos emergentes.

OBJECTIVES: In 2006 the rotavirus vaccine was included in the Brazilian Immunization Program. The aim of this study was to report the results of a 5-year surveillance study of rotavirus strains in children < 5 years with acute gastroenteritis from day care centers in the state of São Paulo, Brazil. METHODS: This retrospective study was conducted with 30 day care centers from 2004 to 2008 with convenient surveillance fecal specimens, investigated by ELISA, SDS-PAGE, RT-PCR and gene sequencing to genotype characterization. RESULTS: Rotavirus infection was detected in 28.3 percent of samples (38/134). The most frequent genotypes detected were G9P[8] and G1P[8] in 2004; G1P[8] in 2005; GNTP[NT] in 2006; G2P[4] in 2007; and there were no cases in 2008. Mixed infections were not observed. Detection rate declined from 65.7 percent (23/35) in 2004 to 50 percent (9/18) in 2007. CONCLUSIONS: Genotype distribution varied according to collection year, accompanied by a reduction in detection rate. Use of rotavirus vaccine requires implementation of post-marketing surveillance to monitor rotavirus strain diversity and its efficacy against possible new emerging genotypes.