RESUMO
Under International Health Regulations from 2005, a human infection caused by a novel influenza A virus variant is considered an event that has potential for high public health impact and is immediately notifiable to the World Health Organisation. We here describe the clinical, epidemiological and virological features of a confirmed human case of swine influenza A(H1N2)v in England detected through community respiratory virus surveillance. Swabbing and contact tracing helped refine public health risk assessment, following this unusual and unexpected finding.
Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Infecções por Orthomyxoviridae , Doenças dos Suínos , Animais , Humanos , Suínos , Vírus da Influenza A Subtipo H1N2 , Vírus da Influenza A Subtipo H1N1/genética , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/epidemiologia , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Inglaterra/epidemiologiaRESUMO
On 5 January 2022, high pathogenicity avian influenza A(H5N1) was confirmed in an individual who kept a large flock of ducks at their home in England. The individual remained asymptomatic. H5N1 was confirmed in 19/20 sampled live birds on 22 December 2021. Comprehensive contact tracing (nâ¯=â¯11) revealed no additional primary cases or secondary transmissions. Active surveillance of exposed individuals is essential for case identification. Asymptomatic swabbing helped refine public health risk assessment and facilitated case management given changes in avian influenza epidemiology.
Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Influenza Humana , Animais , Aves , Patos , Humanos , Influenza Aviária/epidemiologia , Influenza Humana/diagnóstico , Influenza Humana/epidemiologiaRESUMO
Salmonella enterica (e.g., serovars Typhi and Typhimurium) relies on translocation of effectors via type III secretion systems (T3SS). Specialization of typhoidal serovars is thought to be mediated via pseudogenesis. Here, we show that the Salmonella Typhi STY1076/t1865 protein, named StoD, a homologue of the enteropathogenic Escherichia coli/enterohemorrhagic E. coli/Citrobacter rodentium NleG, is a T3SS effector. The StoD C terminus (StoD-C) is a U-box E3 ubiquitin ligase, capable of autoubiquitination in the presence of multiple E2s. The crystal structure of the StoD N terminus (StoD-N) at 2.5 Å resolution revealed a ubiquitin-like fold. In HeLa cells expressing StoD, ubiquitin is redistributed into puncta that colocalize with StoD. Binding assays showed that StoD-N and StoD-C bind the same exposed surface of the ß-sheet of ubiquitin, suggesting that StoD could simultaneously interact with two ubiquitin molecules. Consistently, StoD interacted with both K63- (KD = 5.6 ± 1 µM) and K48-linked diubiquitin (KD = 15 ± 4 µM). Accordingly, we report the first S. Typhi-specific T3SS effector. We suggest that StoD recognizes and ubiquitinates pre-ubiquitinated targets, thus subverting intracellular signaling by functioning as an E4 enzyme.