Spike in COVID-19 numbers are not new cases, Royal Borough confirms

An apparent spike in the number of COVID-19 cases in the borough is not due to a sudden surge of people falling ill, the Royal Borough has confirmed – it is the result of a change in measuring system.

Between Thursday, July 2 and Friday, July 3, the number of confirmed cases in the borough appeared to jump from 312 to 399. However, the council has stated that this does not reflect a significant increase in cases.

Until last week, official numbers of COVID-19 cases included only swab tests carried out in Public Health England labs and NHS hospital settings. This is known as ‘Pillar 1’ data.

Recently, official figures have also started including data from swab tests carried out in the community, such as care homes. This is ‘Pillar 2’ data.

These are both different from the ‘R rate’ (reproduction rate), which calculates a disease's ability to spread. This is the number of people that one infected person will pass the virus on to, on average.

On Thursday (July 2), data published through the Government’s official public records on coronavirus.data.gov.uk changed to include cases confirmed through Pillar 1 and Pillar 2 testing combined. It had previously only included Pillar 1 cases.

Accounting for these new figures in conjunction is creating more accurate numbers.

Though the increase in the borough appears sudden, these cases have developed over time and have only just come to light in official figures.