Lifting the lockdown, but adopting strategic distancing, can keep the COVID-19 curve flat - and lead to more compliance with official recommendations than stricter measures, according to a report today from Oxford researchers.
In a study in the journal Nature Human Behaviour, Dr Per Block, Professor Melinda Mills and a team from Oxford’s Leverhulme Centre for Demographic Science, in collaboration with researchers from Zurich, use extensive modelling to show the impact of loosening the lockdown on the course of the virus.
The study backs the creation of ‘social bubbles’ and demonstrates that the infection rate can be kept much lower by strategically reducing contact, than by simple social distancing
The study backs the creation of ‘social bubbles’ and demonstrates that the infection rate can be kept much lower by strategically reducing contact, than by simple social distancing in a post-lockdown world. According to the study, ‘Compliance with recommendations strategically to reduce contact is more favourable than compliance with complete isolation and, thus, can keep the curve flat in the long run.’
Dr Block, lead author of the article states, ‘We demonstrate that strategic reduction of contact can strongly increase the efficiency of social distancing measures, introducing the possibility of allowing some social contact while keeping risks low. This approach provides nuanced insights to policy makers for effective social distancing which can mitigate negative consequences of social isolation.’
Dr Block adds: ‘We demonstrate how simple changes within individuals’ social networks, and network-informed constellations within businesses and schools, can alter the rate and spread of the virus.’
Limiting interaction to a few repeated contacts, was found to be the most effective strategy
The study considers three strategic options:
- Increasing similarity of contacts (homophily), by temporarily restricting contact to those who share key similar features, such as living in the same neighbourhood, where possible.
- Reducing interaction with people who are not connected to one’s usual social contacts, in order to decrease ties that bridge social clusters.
- Repeatedly interacting with the same social contacts (repetition), by creating micro-communities, commonly referred to as ‘social bubbles’.
All three substantially slow the spread of the virus compared to either no intervention or simple, unstrategic social distancing. But the third, limiting interaction to a few repeated contacts, was found to be the most effective strategy. This involves only interacting with a small group, such as people who live within the same neighbourhood, and decreasing potential ties to other social groups - such as occasional acquaintances. This was found to be highly effective, when compared to attempting to reduce contact at random.
Based on the findings, the authors suggest that reducing high-impact contact, with someone from outside their ‘bubble’, can mitigate the adverse social, behavioural and economic impacts of lockdown approaches while keeping risks low.
The authors suggest that reducing high-impact contact, with someone from outside their ‘bubble’, can mitigate the adverse social, behavioural and economic impacts of lockdown approaches while keeping risks low
By offering different social distancing strategies, the team also proposes alternatives to social bubbles in cases, when these are not practicable.
All discussed approaches mitigate the recognised psychological and physical harms of prolonged social distancing. And recommendations to reduce contact strategically may be more palatable to people than complete isolation – and therefore lead to higher adherence.
The study authors show how all three strategies ‘flatten the curve’ across a wide variation in simulated scenarios. According to the study, ‘Since most individuals in a post-lockdown world need to interact across multiple social circles (e.g., workplace, extended family), employing only one strategy might not be practical.’
But this study suggests even a mix of strategies is preferable, compared to adopting no strategies of reducing contact. The really important insight is to recognise the difference between ‘high-impact’ and ‘low-impact’ contacts.
The study authors show how all three strategies ‘flatten the curve’ across a wide variation in simulated scenarios
The research states, ‘Instead of blanket self-isolation policies, the emphasis on similar, community-based, and repetitive contacts is both easy to understand and implement thus making distancing measures more palatable over longer periods of time.’
'Social network-based distancing strategies to flatten the COVID-19 curve in a post-lockdown world', has been scheduled for publication in Nature Human Behaviour on 04 June 2020 at 10:00 (London time).
The paper is available here: https://www.nature.com/articles/s41562-020-0898-6. The Leverhulme Center for Demographic Science was launched in 2019 and brings together researchers from different disciplines to bring science into demography.
