Coxsackievirus A6 strains causing an outbreak of hand-foot-and-mouth disease in Northeastern Brazil in 2018.

Hand-foot-and-mouth disease (HFMD) is a highly contagious viral disease commonly associated to Enteroviruses (EV). During 2018, Brazil faced massive HFMD outbreaks spread across the country. This study aimed to characterize the EV responsible for the HFMD outbreak that occurred in Paraiba State, Brazilian Northeastern region, in 2018, followed by a phylogenetic analysis to detail information on its genetic diversity. A total of 49 serum samples (one from each patient) collected from children ≤ 15 years old, clinically diagnosed with HFMD were tested for EV using conventional RT-PCR and RT-qPCR. EV infection was confirmed in 71.4% (35/49) of samples. The mean and median ages were 1.83 years and one year old, respectively. Twenty-two EV-positive samples were successfully sequenced and classified as EV-A species; 13 samples were also identified with the CV-A6 genotype. The phylogenetic analysis (VP1 region) of three samples revealed that the detected CV-A6 strains belonged to sub-lineage D3. The CV-A6 strains detected here clustered with strains from South America, Europe and West Asia strains that were also involved in HFMD cases during the 2017-2018 seasons, in addition to the previously detected Brazilian CV-A6 strains from 2012 to 2017, suggesting a global co-circulation of a set of different CV-A6 strains introduced in the country at different times. The growing circulation of the emerging CV-A6 associated with HFMD, together with the detection of more severe cases worldwide, suggests the need for a more intense surveillance system of HFMD in Brazil. In addition, this investigation was performed exclusively on serum samples, and the analysis of whole blood samples should be considered and could have shown advantages when employed in the diagnosis of enteroviral HFMD outbreaks.

Enteric adenovirus epidemiology from historical fecal samples in Brazil (1998-2005): Pre-rotavirus vaccine era.

Human adenovirus (HAdV) is recognized as frequent cause of acute gastroenteritis and enteric viruses can be preserved in frozen stored feces for long periods of times. The purpose of the present study was to investigate enteric HAdV genotypic diversity in archival fecal specimens stored from 1998 to 2005 in order to understand the natural history of HAdV in diarrheal patients in Brazil before rotavirus vaccine introduction. A total of 3346 specimens were tested for HAdV using conventional PCR. Genotypes were identified by sequencing. HAdV was detected in 6.8% (228/3346). Positivity was higher in children ≤ 5 years and males (p < 0.05). HAdV was most frequently observed during winter and spring seasons (p < 0.05). HAdV-F41 was the most prevalent genotype (59.2%;135/228), followed by HAdV-F40 (16.2%;37/228), HAdV-C1 (5.2%;12/228), HAdV-C2 (5.2%;12/228), HAdV-C5 (3.1%;7/228), HAdV-A12 (1.3%;3/228), HAdV-E4 (0.9%;2/228), HAdV-B3 (0.9%;2/228) and HAdV-B21 (0.4%;1/228). In 7.6% (17/228) only species D could be defined. HAdV-E4 strains were phylogenetic analyzed and classified as lineage (a)-like PG II. HAdV prevalence remained stable in Brazilian population, regardless rotavirus vaccine introduction. The predominant HAdV genotypes detected did not change over time, highlighting a high diversity of circulating strains in the country throughout decades. Due to the historical lack of HAdV genotyping surveillance in Brazil, HAdV-E4 epidemiology is virtually unknown in the country. The present study contributed significantly to the understanding of the natural history of HAdV in diarrheal patients in Brazil. The acquired data are important for clinical diagnosis, particularly for studies investigating enteric viruses' prevalence and molecular epidemiology of archival clinical specimens.

Coxsackievirus A6 strains causing an outbreak of hand-foot-and-mouth disease in Northeastern Brazil in 2018

ABSTRACT Hand-foot-and-mouth disease (HFMD) is a highly contagious viral disease commonly associated to Enteroviruses (EV). During 2018, Brazil faced massive HFMD outbreaks spread across the country. This study aimed to characterize the EV responsible for the HFMD outbreak that occurred in Paraiba State, Brazilian Northeastern region, in 2018, followed by a phylogenetic analysis to detail information on its genetic diversity. A total of 49 serum samples (one from each patient) collected from children ≤ 15 years old, clinically diagnosed with HFMD were tested for EV using conventional RT-PCR and RT-qPCR. EV infection was confirmed in 71.4% (35/49) of samples. The mean and median ages were 1.83 years and one year old, respectively. Twenty-two EV-positive samples were successfully sequenced and classified as EV-A species; 13 samples were also identified with the CV-A6 genotype. The phylogenetic analysis (VP1 region) of three samples revealed that the detected CV-A6 strains belonged to sub-lineage D3. The CV-A6 strains detected here clustered with strains from South America, Europe and West Asia strains that were also involved in HFMD cases during the 2017-2018 seasons, in addition to the previously detected Brazilian CV-A6 strains from 2012 to 2017, suggesting a global co-circulation of a set of different CV-A6 strains introduced in the country at different times. The growing circulation of the emerging CV-A6 associated with HFMD, together with the detection of more severe cases worldwide, suggests the need for a more intense surveillance system of HFMD in Brazil. In addition, this investigation was performed exclusively on serum samples, and the analysis of whole blood samples should be considered and could have shown advantages when employed in the diagnosis of enteroviral HFMD outbreaks.

Constelação completa dos genótipos de cepas raras de rotavírus G12P[9] e G12P[6] detectadas no Brasil de 2011-2020 / Complete constellation of genotypes of rare rotavirus strains G12P[9] and G12P[6] detected in Brazil from 2011-2020

Cepas atípicas de RVA isoladas de humanos e animais compartilham características genéticas e antigênicas, sugerindo fortemente uma transmissão interespécie. O G12 é, atualmente, reconhecido como um genótipo emergente globalmente. Neste estudo, foram caracterizados os genomas de três espécies raras G12P[9] (RVA/Human-wt/BRA/IAL-R870/2013/G12P[9], RVA/Human-wt/BRA/IAL-R1151/2012/G12P[9] e RVA/Human-wt/BRA/IAL R566/2011/G12P[9]) e quatro G12P[6] (RVA/Human-wt/BRA/IAL-R86/2011/G12P[6], RVA/Human-wt/BRA/IAL-R465/2019/G12P[6], RVA/Human-wt/BRA/IAL-R52/2020/G12P[6] e RVA/Human-wt/BRA/IAL-R95/2020/G12P[6]) detectadas em amostras de fezes de pacientes com gastroenterite aguda no Brasil durante a Vigilância Nacional de Rotavírus realizada de 2011 a 2020. As cepas foram submetidas a RT-PCR convencional para os 11 segmentos seguido do sequenciamento de Sanger e análise filogenética. Todas as cepas G12P[9] exibiram uma constelação genética AU-1-like (G12-P[9]-I3-R3-C3-M3-A3-N3-T3-E3-H6), enquanto as cepas G12P[6] mostraram a típica DS-1-like (G12-P[6]-I2-R2-C2-M2-A2-N2-T2-E2-H2). A partir do estudo filogenético, as cepas brasileiras IAL G12P[6] DS-1-like mostram ancestralidade genética africana e rearranjos com cepas americanas co-circulantes, sem evidências de transmissão zoonótica recente. Em relação às cepas brasileiras IAL G12P[9], estas evidenciam ancestralidade genética asiática e observa-se a evidência de transmissão interespecífica entre cepas humanas G12P[9] AU-1-like e cepas felinas/caninas...(AU)

Atypical RVA strains isolated from humans and animals share genetic and antigenic features, strongly suggesting an interspecies transmission. G12 type are currently recognized as a globally emerging genotype. In this study, were characterized the complete genomes of three rare G12P[9] (RVA/Human-wt/BRA/IAL-R870/2013/G12P[9], RVA/Human-wt/BRA/IAL-R1151/2012/G12P[9] and RVA/Human-wt/BRA/IAL-R566/2011/G12P[9]) and four G12P[6] (RVA/Human-wt/BRA/IAL-R86/2011/G12P[6], RVA/Human-wt/BRA/IAL-R465/2019/G12P[6], RVA/Human-wt/BRA/IAL-R52/2020/G12P[6] and RVA/Human-wt/BRA/IAL-R95/2020/G12P[6]) strains detected in stool samples from patients with acute gastroenteritis in Brazil during National Brazilian Rotavirus surveillance conducted from 2011 to 2020. The RVA strains were submitted to conventional RT-PCR targeting the 11 gene segments followed by Sanger sequencing and phylogenetic analysis. All G12P[9] strains displayed an AU-like genetic backbone constellation (G12-P[9]-I3-R3-C3-M3-A3-N3-T3-E3-H6), while G12P[6] strains showed the typical DS-1-like genetic backbone (G12-P[6]-I2-R2-C2-M2-A2-N2-T2-E2-H2). From the phylogenetic study, the Brazilian IAL G12P[6] DS-1-like strains show African genetic ancestry and rearrangements with co-circulating American strains belonging to the DS-1-like constellation, without evidence of recent zoonotic transmission. On other hand, the Brazilian IAL G12P[9] strains show Asian genetic...(AU)