ABSTRACT
Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.
Subject(s)
Angiotensins , Genome , BetacoronavirusABSTRACT
ABSTRACT Introduction: Sexually transmitted infections (STI) remain a major public health problem and surveillance is crucial for prevention and control strategies. Objective: Our aim was to assess the prevalence of STI in a reference center for gynecology in Rio de Janeiro, Brazil. Materials and methods: It is a cross-sectional study conducted between August 2016 and June 2017. Whole blood and cervical cells were collected from 62 women and tested for human papillomavirus (HPV), human immunodeficiency virus (HIV), syphilis, chlamydia, gonorrhea and herpes simples virus 1 and 2 (HSV-1/2). Cervical lesions were diagnosed by cytopathology and in some patients by colposcopy (79%). Other STI were evaluated during clinical examination. Results: Cervical lesions were detected by cytopathology examinations in 46.8% of patients; those with a history of four sexual partners were at higher risk of developing them. There was moderate agreement between the cytopathology e colposcopy results (Kappa = 0.69). The prevalence of HSV (96.7%), syphilis (6.4%) and HIV (3.2%) were higher than that described in the literature, while the prevalence of chlamydia (6.4%) and gonorrhea (1.6%) were similar. HPV was detected in 53.2% of women, 32.3% of which were infected by HPV 16. In the context of co-infections, 38 women (61.3%) presented more than one STI. Conclusion: Since most of the women analyzed were affected by more than one STI, our results suggest that routine screening for these infections at health centers would help in early detection, treatment and prevention of these infections. These measures would also impact on patients' cervical cancer control.
RESUMO Introdução: As infecções sexualmente transmissíveis (ISTs) ainda são um importante problema de saúde pública, e a vigilância é essencial para sua prevenção e seu controle. Objetivo: Avaliar a prevalência das ISTs em uma unidade de referência ginecológica no Rio de Janeiro, Brasil. Materiais e métodos: Trata-se de um estudo transversal realizado entre agosto de 2016 e junho de 2017. Foram coletados sangue total e células cervicais de 62 mulheres e realizados testes para detecção de papiloma vírus humano (HPV), vírus da imunodeficiência humana (HIV), sífilis, clamídia, gonorreia e vírus do herpes simples 1 e 2 (HSV-1/2). As lesões cervicais foram diagnosticadas por citopatologia, e em algumas pacientes, por colposcopia (79%). Outras ISTs foram avaliadas durante o exame clínico. Resultados: Foram encontradas lesões cervicais pelo exame citopatológico em 46,8% das pacientes; aquelas com história de quatro parceiros sexuais tiveram mais risco de desenvolvê-las. Houve concordância moderada entre os resultados da citopatologia e colposcopia (Kappa = 0,69). A prevalência de HSV (96,7%), sífilis (6,4%) e HIV (3,2%) foi maior que a descrita na literatura, enquanto a prevalência de clamídia (6,4%) e gonorreia (1,6%) foi similar. O HPV foi detectado em 53,2% das mulheres, sendo 32,3% delas infectadas pelo HPV 16. No contexto das coinfecções, 38 mulheres (61,3%) tinham mais de uma IST. Conclusão: Visto que a maioria das mulheres analisadas era acometida por mais de uma IST, nossos resultados sugerem que uma triagem rotineira dessas infecções nas unidades de saúde poderia auxiliar na detecção precoce, bem como no tratamento e na prevenção. Essas medidas também impactariam no controle do câncer cervical das pacientes.
ABSTRACT
Through microsatellite analysis of 53 monoclonal populations of Trypanosoma cruzi, we found a remarkable degree of genetic polymorphism with no single multilocus genotype being observed more than once. The microsatellite profile proved to be stable during 70 generations of the CL Brener clone in culture. The microsatellite profiling presented also high diagnostic sensitivity since DNA amplifications could be achieved with less than 100 fg DNA, corresponding to half parasite total DNA content. Based on these technical attributes the microsatellite assay turns out to be an important tool for direct typing T. cruzi in biological samples. By using this approach we were able to type T. cruzi in feces of artificially infected bugs and in single cells sorted by FACS. The microsatellites have shown to be excellent markers for T. cruzi phylogenetic reconstruction. We used maximum parsimony based on the minimum number of mutational steps to build an unrooted Wagner network, which confirms previous conclusions based on the analysis of the D7 domain of the LSU rDNA gene that T. cruzi is composed by two major groups. We also obtained evidence that strains belonging to rRNA group 2 are subdivided into two genetically distant clusters, and that one of these clusters is more related to rRNA group 1/2. These results suggest different origins for these strains