School closures during the Covid-19 pandemic have "severely ruptured" the social and emotional development of some of the world's poorest children, as well as their academic progress, new studies have shown.
Children who, prior to the pandemic, felt confident talking to others or got on well with peers were less likely to do so by 2021.
Those who were already disadvantaged educationally- girls, the very poorest, and those from rural areas- seem to have been particularly badly affected.
Two interlinked studies, involving 8,000 primary pupils altogether and published in the journal Longitudinal and Life Course Studies, indicate children lost at least a third of a year in learning.
In a study of over 2,000 primary school pupils in Ethiopia, researchers found that key aspects of children's social and emotional development, such as their ability to make friends, not only stalled during the school closures, but probably deteriorated.
Both this research and a second, linked study of around 6,000 grade 1 and 4 primary school children, also found evidence of slowed academic progress.
Children lost the equivalent of at least one third of an academic year in learning during lockdown - an estimate researchers describe as "conservative".
This appears to have widened an already significant attainment gap between disadvantaged pupils and the rest, and there is some evidence that this may be linked to the drop in social skills.
Both studies were by academics from the University of Cambridge, UK and Addis Ababa University, Ethiopia.
"Covid is having a long-term impact on children everywhere, but especially in lower-income countries. Education aid and government funding must focus on supporting both the academic and socio-emotional recovery of the most disadvantaged children first," said Professor Pauline Rose, Director of the Research in Equitable Access and Learning (REAL) Centre at University of Cambridge.
The most striking evidence of a rupture in socio-emotional development was the lack of a predictive association between the 2019 and 2021 results. Pupils who felt confident talking to others before the pandemic, for example, had often changed their minds two years later.
"These severe ruptures to children's developmental and learning trajectories underline how much we need to think about the impact on social, and not just academic skills. Catch-up education must address the two together," added Professor Tassew Woldehanna, President of Addis Ababa University.
Researchers suggest that the negative impact on social and emotional development may be linked to the slowdown in academic attainment.
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