4.7 Exiting Lockdown
By Josephine Parker
Article last updated: 18/05/20
What happens next?
Many countries have had ‘lockdowns’ in place for a long time now, and the number of new SARS-CoV-2 cases and deaths has been falling for a few weeks. What happens next? Can we start seeing our friends again, and going on holiday? What are the
new rules going to be based on?
Before we can think about exiting lockdown, the net reproduction number, R, must be less than 1 (i.e. the number of new infections must be falling). But in the UK, even with the effort everyone has put in to social distancing
home, at the time of writing this article, R is estimated at between 0.7 and 1
. This doesn't leave much room for manoeuvre. If we let go too quickly, cases may rise again quickly leading straight into another lockdown.
Image credit: www.freepik.com
Staying in Lockdown
So is lifting lockdown too risky? Why not stay put? If we stay in lockdown too long there will be problems too. You may have heard about concerns that lockdown is causing damage to the economy, which could ultimately lead to people losing their jobs.
Changes to health services may be affecting the care given to other patients (e.g. people with cancer), who may suffer from reduced healthcare access. Not to mention impact on school children, who may be struggling with being away from
school and their normal friendship groups.
Let's think about managing risks. Are some activities safer than others?
Close contact between people makes disease transmission more likely. Case-contact tracing and antibody testing show, unsurprisingly, that sharing a household with someone with SARS-CoV-2 puts you at risk of infection[4, 5].
These studies also point to a raised risk of transmission when travelling with an infected individual. Indoor gatherings like bars, night clubs, gyms and religious congregations also appear to be high risk areas. There's less evidence
for transmission of the virus in outdoor settings.
Information like this is used by authorities to guide the advice to the public. For example, in England, people are being told they may now spend unlimited time exercising, and even meet one person who doesn't live with them, as long as they do so outdoors,
while following to the distancing rules.
Let's also think about who's most vulnerable to the disease. We know the elderly and those with underlying health conditions have a high risk of severe symptoms. These people may need to follow different rules.
If R continues to stay under 1 (i.e. cases continue to fall) it may be possible to gradually re-introduce more and more 'low risk' activities. In the UK, a COVID-19 'alert system' is being used to decide what activities we can do, see Figure 1.
Figure 1. The UK's COVID-19
Alert System. Image credit: UK Government.
Contact Tracing App
We spoke about contact tracing in step 2.3 - the idea being that if someone falls ill with the virus, contact tracing is used to find out who they've been in contact with recently (i.e. who they could have infected). Contacts are asked to
self-isolate, and given tests for the virus. But how good is your memory? Can you remember everyone you saw last week? Even the people you didn't know, in shops, or on the bus?
A contact tracing app would help us deal with these gaps. By using Bluetooth or GPS, it can anonymously track the contacts of all users. If one person falls ill with COVID-like symptoms, and is tested positive for COVID-19, all people they have
spent time near recently can be instantly informed, and asked to self-isolate and get tested.
An app like this could be used to stop outbreaks spreading through a population, by catching a large proportion of infected contacts before they infect others.
Making the app work:
Users. The app would have to be used by a lot of people- some researchers estimate 60% of the population - to be effective. There are concerns that older people may find the app hard to use. Other people may choose not to download because of
data privacy worries.
Testing. Rapid testing would need to be offered for everyone who is displaying symptoms.
Cooperation. People notified that they have been in contact with a confirmed cases would need to willingly self-isolate.
There are some complications though, one of which is the contribution of asymptomatic cases. Asymptomatic people won't know they have the virus, so won't notify the app, starting the chain of contact tracing. If asymptomatic people spread the disease
to a lot of people, this would make the app less effective.
The app is currently being trialled on the Isle of Wight, and may be rolled out to the rest of the UK soon. If used, a contact-tracing app will likely be only part of the bigger strategy to help easing lockdown restrictions. What do you think? Would you
download the app?
Behavioural Strategies: Social Bubbles
It's likely that physical distancing rules (staying more than 2m away from other people) will continue for some time. But what other behavioural strategies might apply? One idea that's been suggested is the use of social 'bubbles' or 'pods'. This is also
called social contact clustering. In this, two households would be able to socialise exclusively with one another - limiting any infection risk from the outside by their exclusivity. This may be an opportunity to see others, but only if people stick
to their bubble, and don't try and cheat and add in more friends than they should.
Re-opening Workplaces, Shops and Schools
Workplaces, shops, and schools, may re-open soon if ways can be found to limit the transmission risk in these places; keeping people 2 metres apart, asking them to wear face coverings in crowded areas, encouraging good hand hygiene.
A lot of countries are debating whether it is safe to reopen schools. Evidence suggests that school closure has a relatively low impact on disease transmission
, and data shows that children are less likely to develop severe disease (see step 3.1). We're still investigating whether this means children are less likely to become infected in the first place, or pass the disease on. This evidence
will help guide decision making on what is safe for students and teachers.
Until successful treatments and vaccines are developed, it may be necessary for high risk groups to continue living under the rules of the lockdown while lower risk group start to ease out of some of the restrictions. This is tough to comply with, but
may ultimately be the best thing for their health.
Once an effective vaccine for SARS-CoV-2 is developed, tested and available and large scale, we may be able to resume something closer to 'normal life'. However, as discussed in step 4.5, this may not be for 12-18 months.
Looking Around the World
As we move slowly out of lockdown, it will be important to look around the world at strategies in other countries. Different countries are have applied different approaches to lockdown entry and exit, and we'll be able to learn a lot from their successes
and failures. The SARS-CoV-2 has brought about unprecedented changes to our lives, but through thoughtful use of research, we hope that we can control the spread of the virus, and ultimately, save lives.
Contact tracing: the process of identifying people who may have had contact with an infected individual (“contacts”), testing them for infection, treating the infected and tracing their contacts in turn. The public health aim being to
reduce the number of new infections in a population.
Shielding: When high-risk groups (such as the elderly, or people with underlying health conditions) are asked to avoid contact with others as far as possible, to minimise their risk of catching a disease.
Social Distancing: The practice of maintaining a greater than usual physical distance (such as six feet or more) from other people.
1. Social Contact Clustering Explained: https://www.lshtm.ac.uk/newsevents/expert-opinion/hairclips-and-coronavirus-how-contact-clustering-may-allow-partial
2. Further information on the NHS COVID-19 App: https://www.nhsx.nhs.uk/covid-19-response/nhs-covid-19-app/
Government Publishes Latest R Number. Accessed 18/05/20 https://www.gov.uk/government/news/government-publishes-latest-r-number
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Wellcome Open Research. 2020;5. https://wellcomeopenresearch.org/articles/5-54/v1
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study. The Lancet Infectious Diseases. 2020 Apr 27. https://www.thelancet.com/action/showPdf?pii=S1473-3099%2820%2930287-5
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6. Leclerc QJ, Fuller NM, Knight LE, Funk S, Knight GM, CMMID COVID-19 Working Group. What settings have been linked to SARS-CoV-2 transmission clusters?. Wellcome Open Research. 2020 May 1;5(83):83.
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Child & Adolescent Health. 2020 Apr 6. https://www.thelancet.com/journals/lanchi/article/PIIS2352-4642(20)30095-X/fulltext