Human Parvovirus B19 (B19V) is a recognized cause of life-threatening conditions among patients with hemoglobinopathies. This study investigates B19V infection in patients with sickle cell disease and β-thalassemia using different experimental approaches. A total of 183 individuals (144 with sickle cell disease and 39 with β-thalassemia major) and 100 healthy blood donors were examined for B19V using anti-B19V IgG enzyme immunoassay, quantitative PCR, DNA sequencing, and phylogenetic analysis. Viremia was documented in 18.6% of patients and 1% of donors, and was generally characterized by low viral load (VL); however, acute infections were also observed. Anti-B19V IgG was detected in 65.9% of patients with sickle cell disease and in 60% of donors, whereas the patients with thalassemia exhibited relatively low seroreactivity. The seroprevalence varied among the different age groups. In patients, it progressively increased with age, whereas in donors it reached a plateau. Based on partial NS1 fragments, all isolates detected were classified as subgenotype 1A with a tendency to elicit genetically complex infections. Interestingly, quasispecies occurred in the plasma of not only patients but also donors with even higher heterogeneity. The partial NS1 sequence examined did not exhibit positive selection. Quantitation of B19V with a conservative probe is a technically and practically useful approach. The extensive spread of B19V subgenotype 1A in patients and donors and its recent introduction into the countryside of the São Paulo State, Brazil were demonstrated; however, it is difficult to establish a relationship between viral sequences and the clinical outcomes of the infection.

Clinical research is necessary for an effective response to an emerging infectious disease outbreak. However, research efforts are often hastily organised and done using various research tools, with the result that pooling data across studies is challenging. In response to the needs of the rapidly evolving COVID-19 outbreak, the Clinical Characterisation and Management Working Group of the WHO Research and Development Blueprint programme, the International Forum for Acute Care Trialists, and the International Severe Acute Respiratory and Emerging Infections Consortium have developed a minimum set of common outcome measures for studies of COVID-19. This set includes three elements: a measure of viral burden (quantitative PCR or cycle threshold), a measure of patient survival (mortality at hospital discharge or at 60 days), and a measure of patient progression through the health-care system by use of the WHO Clinical Progression Scale, which reflects patient trajectory and resource use over the course of clinical illness. We urge investigators to include these key data elements in ongoing and future studies to expedite the pooling of data during this immediate threat, and to hone a tool for future needs.

Brazil experienced a large dengue virus (DENV) epidemic in 2019, highlighting a continuous struggle with effective control and public health preparedness. Using Oxford Nanopore sequencing, we led field and classroom initiatives for the monitoring of DENV in Brazil, generating 227 novel genome sequences of DENV1-2 from 85 municipalities (2015–2019). This equated to an over 50% increase in the number of DENV genomes from Brazil available in public databases. Using both phylogenetic and epidemiological models we retrospectively reconstructed the recent transmission history of DENV1-2. Phylogenetic analysis revealed complex patterns of transmission, with both lineage co-circulation and replacement. We identified two lineages within the DENV2 BR-4 clade, for which we estimated the effective reproduction number and pattern of seasonality. Overall, the surveillance outputs and training initiative described here serve as a proof-of-concept for the utility of real-time portable sequencing for research and local capacity building in the genomic surveillance of emerging viruses.

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BackgroundThe genus Lippia comprises 150 species, most of which have interesting medicinal properties. Lippia sidoides (syn. L. origanoides) exhibits strong antimicrobial activity and is included in the phytotherapy program implemented by the Brazilian Ministry of Health. Since species of Lippia are morphologically very similar, conventional taxonomic methods are sometimes insufficient for the unambiguous identification of plant material that is required for the production of certified phytomedicines. Therefore, genetic and chemical analysis with chemotype identification will contribute to a better characterization of Lippia species.MethodsAmplified Length Polymorphism and Internal Transcribed Spacer molecular markers were applied to determine the plants’ genetic variability, and the chemical variability of Lippia spp. was determined by essential oil composition.ResultsAmplified Length Polymorphism markers were efficient in demonstrating the intra and inter-specific genetic variability of the genus and in separating the species L. alba, L. lupulina and L. origanoides into distinct groups. Phylogenetic analysis using Amplified Length Polymorphism and markers produced similar results and confirmed that L. alba and L. lupulina shared a common ancestor that differ from L. origanoides. Carvacrol, endo-fenchol and thymol were the most relevant chemical descriptors.ConclusionBased on the phylogenetic analysis it is proposed that L. grata should be grouped within L. origanoides due to its significant genetic similarity. Although Amplified Length Polymorphism and Internal Transcribed Spacer markers enabled the differentiation of individuals, the genotype selection for the production of certified phytomedicines must also consider the chemotype classification that reflects their real medicinal properties.Electronic supplementary materialThe online version of this article (10.1186/s13104-018-3839-y) contains supplementary material, which is available to authorized users.

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Pubertal male Wistar rats were submitted to bilateral castration and killed 7 or 14 days later; an additional group of castrated rats was submitted to ultrasound stimulation of the ventral region lying above the accessory sex glands, for 20 min a day from the 7th to the 14th day postcastration. Control intact rats were age-matched to the different treated groups. Seminal vesicle growth and secretory activity were investigated on the basis of weight and fructose content, respectively. A progressive fall in seminal vesicle weight was observed over a period of 7 (83% decrease) to 14 (92% decrease) days following castration; ultrasound treatment beginning on the 7th day prevented this additional weight reduction. Castration caused also a marked decrease (50-60%) in the fructose content of the seminal vesicle and the ultrasound energy promoted a partial recovery of the secretory activity of the gland. The results revealed a direct ultrasound stimulation of the seminal vesicle secretory activity in pubertal rats deprived of testicular androgens.

Objectives: Hepatitis A virus (HAV) infection is considered highly endemic in Brazil, especially in lowincome areas. In contrast, only a few human cases of hepatitis E have been reported. This study aimed to estimate the prevalence and potential risk factors of HAV and hepatitis E virus (HEV) infections in an adult population from a rural township of southeastern Brazil. Methods: We conducted a cross-sectional survey using serum samples from urban and rural residents of Cássia dos Coqueiros, São Paulo state. A total of 990 samples were tested for anti-HAV IgG by chemiluminescent microparticle immunoassay, and a subset of 248 samples tested for anti-HEV IgG, using two commercial ELISA. Variables associated with anti-HAV and anti-HEV positivity were assessed by a multivariate analysis using a binomial logistic regression model. Results: Seroprevalence of HAV and HEV was 89.1% and 20.7%, respectively. Age was significantly associated with HAV infection. Wantai and Mikrogen ELISA yielded comparable HEV seroprevalence results. Conclusions: Anti-HAV seroprevalence has declined and correlates with age, whereas anti-HEV was significantly higher than that found in previous population-based studies. These results indicate a need for further investigations of the magnitude of HEV infection in Brazil using the currently available, more sensitive diagnostic methods.