Full genotype characterization of Brazilian canine G3P[3] strains during a 10-year survey (2012-2021) of rotavirus infection in domestic dogs and cats.

There is a dearth of information on the molecular epidemiology of rotaviruses in pets in Brazil. The aim of this study was to monitor rotavirus infections in household dogs and cats, determine full-genotype constellations, and obtain data on evolutionary relationships. Between 2012 and 2021, 600 fecal samples from dogs and cats (516 and 84, respectively) were collected at small animal clinics in São Paulo state, Brazil. Rotavirus screening was conducted using ELISA, PAGE, RT-PCR, sequencing, and phylogenetic analysis. Rotavirus type A (RVA) was detected in 0.5% (3/600) of the animals. No non-RVA types were detected. The three canine RVA strains were found to have a novel genetic constellation, G3-P[3] -I2-R3-C2-M3-A9-N2-T3-E3-H6, which has never been reported in dogs. As expected, all of the viral genes, except those encoding NSP2 and VP7, were closely related to the corresponding genes from canine, feline, and canine-like-human RVA strains. A novel N2 (NSP2) lineage was identified, grouping together Brazilian canine, human, rat and bovine strains, suggesting that genetic reassortment had occurred. Uruguayan G3 strains obtained from sewage contained VP7 genes that were phylogenetically close to those of the Brazilian canine strains, which suggests that these strains are widely distributed in pet populations in South American countries. For the NSP2 (I2), NSP3 (T3), NSP4 (E3), NSP5 (H6), VP1 (R3), VP3 (M3), and VP6 (I2) segments, phylogenetic analysis revealed possibly new lineages. The epidemiological and genetic data presented here point out the necessity for collaborative efforts to implement the One Health strategy in the field of RVA research and to provide an updated understanding of RVA strains circulating canines in Brazil.

Surveillance and molecular characterization of human sapovirus in patients with acute gastroenteritis in Brazil, 2010 to 2017.

BACKGROUND: Human sapoviruses (HuSaV) are associated with acute gastroenteritis (AGE), causing sporadic cases and outbreaks in patients worldwide. In Brazil, however, there are few reports describing the prevalence of HuSaV in patients with AGE. OBJECTIVE: Describing the diversity of HuSaV in Brazil by detecting and molecularly characterizing HuSaV among patients with AGE during an 8-year period (2010-2017). STUDY DESIGN: A total of 3974 stool samples, testing negative for rotavirus (RVA), norovirus (NoV) and human adenovirus (HAdV), were selected and screened for the presence of HuSaV. Nested RT-PCR were performed for a partial region of VP1, sequenced and genetic analyzed for genotyping the positive samples. RESULTS: In the current study, the HuSaV prevalence was determined to be 3.7% (149/3974). A higher prevalence, 5.7% (118/2074), was observed in children under 2 years of age. During the surveillance period, 13 outbreaks were detected: 12 outbreaks in children under 3 years old and one outbreak in adults. Among the 149 HuSaV positive cases, 106 samples (71%) were successfully sequenced. The most prevalent genotype found was GI.1 (44.3%), followed by GI.2 (21.7%), GI.3 (3.8%), GI.6 (2.8%), GII.1 (5.7%), GII.2 (8.5%), GII.3 (2.8%), GII.4 (2.8%), GII.5 (5.7%) and GIV.1 (1.9%). Two GIV.1 strains characterized in this study are, to date, the only strains of this genotype reported in Brazil. CONCLUSIONS: The present study elucidated the circulation of HuSaV in Brazil and highlight that HuSaV has not assumed an epidemiological importance in the country after the introduction of the RVA vaccine.

Surveillance and molecular characterization of human adenovirus in patients with acute gastroenteritis in the era of rotavirus vaccine, Brazil, 2012-2017.

BACKGROUND: In Brazil, limited data are available regarding the incidence and molecular epidemiology of Human Adenovirus (HAdV) in diarrheic disease, especially in the post rotavirus (RVA) vaccine era. OBJECTIVE: The aims of the study were to investigate the frequency of HAdV infections in patients with gastroenteritis during a 6-year period (2012-2017); conduct molecular typing of positive strains, and obtain further information on the HAdV seasonality. STUDY DESIGN: A total of 3003 fecal samples negative for both, RVA and Norovirus, were selected and tested for HAdV by PCR. Positive HAdV samples were sequenced to obtain genotype identification. RESULTS: HAdV was detected in 3.9% (117/3003); 76 belong to species F (70 HAdV-F41; 6 HAdVF40), 31 to species C (15 HAdV-C1; 13 HAdV-C2; 3 HAdV-C5), 5 belong to species D (3 HAdVD56 and 2 untyped), 4 belong to species A (2 HAdV-A12; 2 HAdV-A31), and 1 belong to HAdVB3. Detection rate significantly varied according to the year, suggesting that HAdV infections show a tendency to occur in natural oscillatory fluctuation. No consistent seasonal pattern was identified. Children ≤5 years exhibited higher positivity rate, reinforcing that HAdV is an important pathogen in childhood diarrhea. Genetic analysis indicated that HAdV strains circulating in Brazil were closely related to worldwide strains, and there is no evidence for the introduction of a particular HAdV variant in the country. CONCLUSIONS: The present investigation does not suggest that HAdV has assumed an epidemiological importance in Brazil after the RVA vaccine introduction and contributed to the definition of the clinical and public health significance of HAdV infections.