Seroprevalence of hepatitis E virus in risk populations and blood donors in a referral hospital in the south of Brazil

The prevalence of anti-hepatitis E virus (HEV) antibodies has a high heterogeneity worldwide. South American data are still scarce. The aim of this study was to evaluate the prevalence of HEV in populations at risk in comparison to blood donors (BD). A cross-sectional study was carried out in adults of different risk populations including crack users (CK), residents in a low income area (LIA), cirrhotic (CIR) and liver transplant patients (LT) compared with BD. The WANTAI HEV ELISA test was used and real-time PCR (in-house for screening and ALTONA as confirmatory test) for HEV RNA screening. A total of 400 participants were included. Anti-HEV IgG was positive in 19.5% of the total sample, reaching the highest rate in the CIR group, 22.5%, followed by CK, LT, and LIA (20%, 18.7%, and 17.5%, respectively). The prevalence found in BD individuals was of 18.7% (p = NS). Anti-HEV IgM was positive in only 1.5% of the sample (6/400). No blood or stools samples were positive for HEV RNA. The seroprevalence reported is among the highest rates ever found in Brazil. Considering the intense diagnostic investigation, data show that HEV circulation is more common that might be expected in our country

Molecular characterization of hepatitis A virus strains involved in the outbreak identified in the city of São Paulo from 2017 to 2019

Casos de hepatite A são frequentes em áreas endêmicas, nas quais os baixos níveis socioeconômicos exercem influência direta no saneamento básico, medidas de higiene e hábitos particulares dos indivíduos, que acabam gerando um cenário perfeito para a proliferação do vírus e o acometimento da população durante os primeiros anos de vida. Em contrapartida, em regiões não endêmicas, onde há países de alto poder socioeconômico com medidas adequadas de higiene, saneamento básico e bons hábitos da população, a prevalência é baixa e a susceptibilidade da população de jovens e adultos é alta, resultando em surtos no momento em que ocorre a introdução do vírus entre essa população. Apesar da típica transmissão dessa infecção por via fecal-oral por meio de água e alimentos contaminados, nos últimos anos a disseminação tem sido associada às práticas sexuais, principalmente pela prática do sexo oro-anal, observada mais frequentemente entre homens que fazem sexo com homens (HSH). Na Europa, durante o último surto que teve início já no final de 2016, foram acometidos cerca de 22 países europeus com 4.475 casos notificados até setembro de 2018, com a predominância da população HSH. Esse surto, inicialmente relatado nos países europeus, foi observado nos países da América do Norte e do Sul, como no Brasil e, em particular, na cidade de São Paulo. Dados publicados forneceram importantes informações epidemiológicas acerca do município de São Paulo com 1547 casos notificados no período de 2016 até outubro de 2019, sendo destes 1266 (82,0%) indivíduos do sexo masculino e desses, 503 (41,0%) relatando provável contaminação pela via sexual. Sabe-se que os genótipos (I,II e III) e os subgenótipos (IA, IB, IIA, IIB, IIIA e IIIB) do vírus da hepatite A (HAV) apresentam uma distribuição geográfica característica, portanto a identificação molecular das cepas do HAV envolvidas na infecção é de grande relevância para o entendimento da origem da infecção e de suas rotas de transmissão. Este estudo teve como objetivo principal a caracterização da epidemiologia molecular e o estudo das relações filogenéticas das cepas de HAV isoladas dos casos de infecção aguda atendidos em instituições de referência da cidade de São Paulo no período de setembro/2017 a maio/2019. Foram incluídas amostras com sorologia confirmada para hepatite A (anti-HAV IgM positivo) de 51 casos, destes a maioria (80,3%; 41/51) era do sexo masculino e na faixa etária entre 20 e 40 anos (68,6%). O HAV RNA foi detectado por nested RT-PCR utilizando primers que amplificam um fragmento de 267 pares de base (pb) da região genômica VP1-2A em 92% (47/51) das amostras, de 89,4% (42/47) dessas foi possível também amplificar a região VP1 completa (953 pb). As amostras amplificadas foram sequenciadas para posterior análise genotípica. Todas as sequências caracterizadas neste estudo foram classificadas dentro do subgenótipo IA; observou-se o agrupamento das mesmas em cinco clados, e a maioria das sequências isoladas dos casos de São Paulo agruparam juntamente com as sequências isoladas dos surtos que ocorreram em diferentes países da Europa em 2016Hepatitis A cases are frequent in endemic areas with low socioeconomics levels, associated with poor sanitation and hygienic measures resulting in a perfect scenario for the proliferation of the virus and infection of the population involvement during the first years of life. On the other hand, in non-endemic regions, where there are countries witht high socioeconomic power and adequate measures of hygiene, basic sanitation and good habits of the population, the prevalence is low and the susceptibility of the young and adult population is high, resulting in outbreaks. Despite the typical transmission of this infection via the fecal-oral route through contaminated water and food, in recent years the spread has been associated with sexual practices, mainly through the practice of oroanal sex, observed more frequently among men who have sex with men (MSM). In Europe, during the last outbreak that started at the end of 2016, around 22 European countries were affected, with 4,475 cases reported up to September 2018, with the predominance of the MSM population. This outbreak, initially reported in European countries, was observed in the countries of North and South America, such as Brazil and, in particular, in the city of São Paulo. Published data provided important epidemiological information about the municipality of São Paulo with 1547 cases from 2016 to October 2019, of which 1266 (82.0%) were male and 503 (41.0%) reported probable contamination via the sexual route. It is known that the genotypes (I, II and III) and subgenotypes (IA, IB, IIA, IIB, IIIA and IIIB) of the hepatitis A virus (HAV) have a characteristic geographical distribution, therefore the molecular identification of strains of the HAV involved in the infection is of great relevance for understanding the origin of the infection and its transmission routes. This study had as its main objective the characterization of molecular epidemiology and the study of the phylogenetic relationships of HAV strains isolated from cases of acute infection treated at reference institutions in the city of São Paulo in the period from 2017 to 2019. Samples with confirmed serology were included for hepatitis A (anti-HAV IgM positive) of 51 cases, most of them (80.3%; 41/51) were male and aged between 20 and 40 years (68.6%). HAV RNA was detected by nested RT-PCR from the VP1-2A genomic region in 92% (47/51) of the samples and amplified from the complete VP1 genomic region in 89.4% (42/47) of the samples, of which 95.2% (40/42) were sequenced for further genotypic analysis. The viral subgenotype could be classified as subgenotype IA in all sequences. The sequences characterized in this study grouped into five clades and the phylogeny showed the grouping of most of the isolated sequences of the São Paulo cases together with the isolated sequences of the outbreaks that occurred in different European countries in 201

Mosquito pornoscopy: Observation and interruption of <i>Aedes aegypti</i> copulation to determine female polyandric event and mixed progeny

<div><p>Ades aegypti is the most important arbovirus vector in the world, and new strategies are under evaluation. Biological studies mentioning the occurrence of a second mate in <i>Aedes aegypti</i> can interfere with vector control program planning, which involves male mosquito release technique. This study presents different experiments to show the occurrence of mixed progeny. Mixed male crosses (using a combination of different type of males in confinement with virgin females) showed no polyandric female. Individual crosses with male substitution in every gonotrophic cycle also did not show any polyandric female. Individual crosses with a 20 minutes interval, with subsequent male change, showed that only a few females presented mixed offspring. The copulation breach in three different moments, group A with full coitus length, group B the coitus was interrupted in 5–7 seconds after the start; and group C, which the copulation was interrupted 3 seconds after started. In summary, group A showed a majority of unique progeny from the first male; group B showed the higher frequency of mixed offspring and group C with the majority of the crosses belonging to the second male. To conclude, the occurrence of a viable second mate and mixed offspring is only possible when the copulation is interrupted; otherwise, the first mate is responsible for mixed progeny.</p></div

Average number of eggs, mean hatch rate and number of crosses with mixed/unique type of progeny in 20 minutes interval for first male cross.

<p>Average number of eggs, mean hatch rate and number of crosses with mixed/unique type of progeny in 20 minutes interval for first male cross.</p

Total number of crosses among the progeny type and the initial male.

<p>Total number of crosses among the progeny type and the initial male.</p

Model probability distribution of crosses among the progeny type and the initial male.

<p>Model probability distribution of crosses among the progeny type and the initial male.</p

Method illustration of the male exchange experiment.

<p>Method illustration of the male exchange experiment.</p

The Molecular Characterization of Hepatitis A Virus Strains Circulating during Hepatitis A Outbreaks in S&atilde;o Paulo, Brazil, from September 2017 to May 2019

Outbreaks of hepatitis A may occur in countries of medium and high socioeconomic levels in which the population generally exhibits an increased susceptibility in young adults to this infection if they are not vaccinated against the hepatitis A virus (HAV). In Europe, an outbreak involved approximately 22 European countries with 4475 cases reported from 2016 to 2018; most of them were men who have sex with men (MSM). This outbreak expanded to North and South America, including Brazil, particularly in S&atilde;o Paulo city with 1547 reported cases from 2016 to 2019. In the present study, we characterized the HAV strains involved in the acute hepatitis A cases identified in the reference centers of S&atilde;o Paulo city during this outbreak. A total of 51 cases with positive anti-HAV IgM were included, 80.4% male, 68.6% of them between 20 and 40 years old and 41.7% MSM. HAV RNA was detected in 92% (47/51) of the cases. Subgenotype IA of HAV was identified and most of the strains were closely related to that isolated in outbreaks that occurred in different European countries in 2016. These results showed the epidemiological relation between these outbreaks and reinforce the need to implement vaccination against hepatitis A for the adult population, particularly for a population with a high-risk behavior

Number of crosses of each interrupted mating group according to the initial male.

<p>Number of crosses of each interrupted mating group according to the initial male.</p

Average number of eggs and hatch rate through a consecutive male change throughout different gonotrophic cycles and its progeny status.

<p>Average number of eggs and hatch rate through a consecutive male change throughout different gonotrophic cycles and its progeny status.</p