Within-host evolutionary dynamics of seasonal and pandemic human influenza A viruses in young children.

The evolution of influenza viruses is fundamentally shaped by within-host processes. However, the within-host evolutionary dynamics of influenza viruses remain incompletely understood, in part because most studies have focused on infections in healthy adults based on single timepoint data. Here, we analysed the within-host evolution of 82 longitudinally-sampled individuals, mostly young children, infected with A/H1N1pdm09 or A/H3N2 viruses between 2007 and 2009. For A/H1N1pdm09 infections during the 2009 pandemic, nonsynonymous minority variants were more prevalent than synonymous ones. For A/H3N2 viruses in young children, early infection was dominated by purifying selection. As these infections progressed, nonsynonymous variants typically increased in frequency even when within-host virus titres decreased. Unlike the short-lived infections of adults where de novo within-host variants are rare, longer infections in young children allow for the maintenance of virus diversity via mutation-selection balance creating potentially important opportunities for within-host virus evolution

Within-host evolutionary dynamics of seasonal and pandemic human influenza a viruses in young children

The evolution of influenza viruses is fundamentally shaped by within-host processes. However, the within-host evolutionary dynamics of influenza viruses remain incompletely understood, in part because most studies have focused on infections in healthy adults based on single timepoint data. Here, we analysed the within-host evolution of 82 longitudinally-sampled individuals, mostly young children, infected with A/H1N1pdm09 or A/H3N2 viruses between 2007 and 2009. For A/H1N1pdm09 infections during the 2009 pandemic, nonsynonymous minority variants were more prevalent than synonymous ones. For A/H3N2 viruses in young children, early infection was dominated by purifying selection. As these infections progressed, nonsynonymous variants typically increased in frequency even when within-host virus titres decreased. Unlike the short-lived infections of adults where de novo within-host variants are rare, longer infections in young children allow for the maintenance of virus diversity via mutation-selection balance creating potentially important opportunities for within-host virus evolution

Primary English language education policy in Vietnam: Insights from implementation

The introduction of English in primary education curricula is a phenomenon occurring in many non-English-speaking countries in Asia, including Vietnam. Recently, the Ministry of Education and Training (MOET) in Vietnam issued guidelines for the piloting of an English as a foreign language (EFL) primary curriculum in which English is taught as a compulsory subject from Grade 3; however, there is limited research on the practices required to successfully implement this policy. This paper reports on a study that looked at the implementation of the primary English language policy in terms of the policy goals in two primary schools, one private and the other public, in Hanoi to shed light on the practice of EFL teaching at the primary level in Vietnam. The research was conducted as an exploratory case study with data collected from multiple sources, including classroom observations and interviews with different stakeholders. The results revealed variation in the implementation of primary English education between the two schools, with the private school providing better outcomes. The language planning issues discussed in this study, including teacher supply, training and professional development, resourcing, teaching methods, and materials, have been raised in previous educational research in Vietnam. However, despite being a new start to primary English, the 2010 programme seems to have done little to improve policy implementation in these areas, hindering the effectiveness of teaching English in schools. This study suggests a number of ways the current situation might be improved