There is currently considerable media coverage and some public anxiety in the UK about Group A streptococcal (GAS) infections. Journalists who write about cases of infectious diseases need to understand the principles of the Poisson distribution. Events such as infections can sometimes cluster in time or space due to chance, and not because there is an underlying cause behind the cluster of cases.
Some journalists and doctors are stating that the cases of Group A streptococcal infections we are currently seeing in the UK are from lower levels of immunity because of Covid-19 control measures over the last 2.5 years. This is not necessarily the case and needs further investigation. The UK has experienced large outbreaks of Group A streptococcal infections in the past. For example, the UK had a large outbreak of Group A streptococcal infections between September 2015 and April 2016 (the largest since 1969), resulting in PHE issuing an alert.
The current cluster of Group A streptococcal infections won’t be the last we will see in the UK. Outbreaks of this and other infections will continue to occur. What is important is that our public health agencies and the NHS have the capacity to investigate and manage any outbreaks.