# Unlocking the workforce

Professor Miguel Anjos, Dr Lars Schewe, Albert SolĂ  Vilalta and Dr Amy Wilson have contributed to a white paper on guiding principles in the wake of the Covid-19 crisis, as part of a Virtual Study Group (VSG).

The paper, titled "Guiding Principles for Unlocking the Workforce - What Can Mathematics Tell Us?" is about developing principles, based on sound mathematical arguments, that should be considered as people return to their workplaces. These principles address the issue of balancing the need to protect the population from Covid-19 against the economic imperative of opening up workplaces and the broader environment. The work was carried out in response to a request to provide "principles" on how to modify workplace operations in order to reduce viral transmission.

The research was conducted with the following factors in mind:

• Using R, the rate of infection, to identify the mean number a typical infected individual will go on to infect.
• The difference between running hot and cold, with "hot" being where a population's infection rate is unacceptably high and "cold" being the opposite.
• Mathematical models of contact tracing for COVID-19, namely the work of Hellewell et al (2002) and Ferretti et al (2020).
• Responsibility, non-linearity and traceability.

Using these factors, 21 different principles were developed which detail different methods for getting the population back to work in a safe, reliable and scientifically supported way. It should be stressed that while there are strong mathematical arguments for each of the principles, they may not apply in real-world situations.

The 21 principles were loosely grouped together, by type, into four sub-groups:

• The "Firebreak" Principles - Partition the population as far as possible into groups that do not interact.
• "Fixed-desk" Principles - Maintain one-to-one, or one-to-few, interactions wherever possible.
• "Table-Service" Principles - Turn many-to-many into one-to-many interactions where possible.
• "Poorly-Exclusion" Principles - Adjust working patterns to allow regular testing and periodic lockdowns for people who have to interact with many individuals or groups.

The principles are not directly intended to enable decisions about which workplaces may reopen and which must remain shut. Instead they are intended to create guidelines that will inform the design of safe workplace operations and scheduling once it has been decided that a particular workplace is to reopen.