ABSTRACT
ABSTRACT New viruses of the Picornavirales order have been discovered with the increase in the number of sequences obtained by high-throughput sequencing, as well as human stool-associated RNA virus (husavirus [HuV]), found in human stool samples. However, there is much to be clarified about HuV. Its cellular host, evolutionary history, and other biological characteristics are still unknown. Therefore, samples collected from human beings and environmental samples in a watershed in Southern Brazil were processed for the metagenomic library. Upon metagenomic analysis, we identified a HuV (husavirus LMM_67754 OP019707) genome with 8,846 bp, which was reported for the first time in Southern Brazil. The new genome presents only 37% of nucleotide identity with Brazilian strains and more than 90% with genomes from China, Vietnam, Venezuela, and the Netherlands. The HuV phylogeny presents significant differences among genomes, probably because multiple introductions of the virus may have occurred. Many questions still need to be answered about HuV. Therefore, more sequences and studies on this virus are necessary to improve the comprehension of the unknown origin of Picornavirales.
ABSTRACT
BACKGROUND Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.
ABSTRACT
Human mastadenovirus (HAdV) genus is related to several diseases, among them upper and lower respiratory tract illness. HAdV species B, C, D, and E are mainly associated with respiratory infections. The goal of this work was to identify the HAdV species associated with respiratory infections in hospitalized patients from southern Brazil. Samples were collected from 1996 to 2004 and 2011 to 2017. During this period, 28,524 samples were collected, and 9983 were positive for respiratory viruses, being 435 for HAdV. From these 435 samples, 57 were selected for characterization of HAdV species. For screening the presence of HAdV, a partial sequence of the DNA polymerase gene (DNApol gene) was amplified by nested PCR. Partial nucleotide sequencing was performed in positive samples, and HAdV (DNApol gene) was detected in 53 samples: species B (28;49.1%), C (16;8.0%), D (2; 3.5%), E (5; 8.7%), and untyped (2; 3.5%). Specie D was found only in 2017 and specie E in 2011 and 2012. The age of the patients ranged from < 1 to 81 years old, and 62.3%were male. No relationship between gender orage and identified HAdV species were observed. In addition, in the period of 20132017, 18 samples from patients who died were analyzed: 11 were related to species B, 4 to C, and 2 to D and 1 remained untyped. Circulation of HAdV species D and Evaried over the years, but species B and C were present throughout the evaluated period. In addition, respiratory infections by HAdVaffect elderly and children mainly. (AU)