Modelling data shows social distancing works

Date published: 14 May 2020

This data is being regularly collated and assessed by the Department’s specialist modelling group.

The group is chaired by Northern Ireland’s Chief Scientific Advisor Professor Ian Young and includes a number of external experts from the Public Health Agency, Trusts and local Universities.

The group has access to a number of different models, including locally developed models and several different models developed by leading academic groups elsewhere in the UK. In addition, it liaises closely with the modelling group in the Republic of Ireland

Today’s publication by the Department also includes information on the Reproduction (R) Number – the number of other individuals who become infected as a result of contact with a single COVID-19 patient.

It states: “Before the introduction of social distancing almost three other people were infected by each COVID-19 patient in the community (R = 2.8). As a result of social distancing and other restrictions, each COVID-19 patient now infects less than one other individual in the community (R=0.8).

“Hence, we are now seeing a slow decline in the number of community acquired COVID-19 cases, hospital admissions, ICU occupancy and deaths.

“In order to ensure that the number of COVID-19 cases remains at the current level or less in the future, we need to ensure that R0 remains at or below 1. If R increases above one there will be an increase in COVID-19 cases and a risk of a second or subsequent waves of the epidemic.

“Any relaxation of the current restrictions will tend to increase the value of R from its current value and it will be important to use every additional measure we can to keep R below one.

“The most important strategy will be an extensive test/ trace / isolate programme which identifies contacts of every new case and makes sure that they self-isolate at home until we are sure that they do not have the infection.”