Should protective measures be lifted?
How and when should protective measures be relaxed in times of corona without increasing the risk of a second wave of infection? The results of a new study by the University of Oxford should help to clarify precisely these questions.
Research by the internationally recognized University of Oxford and the UK Center for Ecology and Hydrology in Wallingford investigated when and how the corona blocking regulations could be relaxed. The results of the study were published in the frontiers in public health journal.
As the first wave of the COVID-19 pandemic subsides in Europe, many countries are loosening their blocking regulations. Nevertheless, non-systemically relevant workers are recommended to continue working from home if possible. In addition, depending on the federal state, numerous protective measures continue to apply. This raises the important question of when these measures can be canceled.
Effective strategy was determined by a model
The researchers analyzed the number of vulnerable, exposed, infectious and recovered (or deceased) people in the UK with the help of a model, separate for the quarantined and the normal working people. This allowed them to determine the best strategy for loosening the current lockdown. The model created was kept relatively simple in order to make the results easier to interpret and to enable their use in other countries.
Health services must not be overwhelmed
The research group explains that the largest possible number of working people should be allowed to work taking into account a sufficient distance, but without overwhelming the health services. However, it is difficult to predict exactly what will happen when the lockdown ends, as different people will react differently to the loosening. However, if a sufficiently large group of people is considered, mathematical models are able to represent the expected average behavior of a large population group.
All possible scenarios should be considered
The most important thing is to consider a wide range of possible scenarios, the researchers emphasize. In this way, a number of possible increases in infection can be examined. Running tests are then important to check whether an increase in disease exceeds the predicted limits.
What is the best strategy?
The research group concluded that the optimal strategy would be to release about half of the population from lockdown two to four weeks after the first peak of infection had ended. Then wait three or four months for a possible second climax to pass before finally unlocking everyone else. This minimizes deaths and at the same time protects the economy.
What does an optimal solution depend on?
The optimal solution mainly depends on the (little known) recovery rate of people suffering from COVID-19 and the rate of virus transmission, the researchers report. For example, the mortality rate and the incubation period are less important.
First release lockdown for younger people
While the model itself doesn't dictate which people can be released from the lockdown first, the team suggests that this should be the younger section of the population. It is known that younger people are less susceptible to COVID-19. However, the respective population groups should continue to be monitored with the help of tests, since they would be exposed to an increased risk.
Be careful when lifting the lockdown
The research group's message is that decision-makers should act very carefully. Any loosening of the lockdown must be monitored very closely. The model created for the study shows that new waves of infection can occur very quickly if the transmission rates are higher than expected or if more people than expected relax their measures.
Tests need to be expanded
The delayed incubation period between infection and the onset of symptoms means that the effects of the disease appear a few days late. Only if the tests are intensified can we get an accurate picture of how the disease spreads and is controlled, the researchers explain. This will make it possible to react quickly if an uncontrollable second wave occurs. (as)
Author and source information
This text corresponds to the requirements of the medical literature, medical guidelines and current studies and has been checked by medical doctors.
- Thomas Rawson, Tom Brewer, Dessislava Veltcheva, Chris Huntingford, Michael B. Bonsall: How and When to End the COVID-19 Lockdown: An Optimization Approach, in Frontiers in Public Health (Posted Jun 10, 2020), Frontiers in Public Health