For the first time, Public Health England (PHE) has published population surveillance data on possible coronavirus (COVID-19) reinfections, to help monitor and understand the risk of people catching COVID-19 again.
The current data shows that there is a low risk of reinfection with SARS-CoV-2. There were 15,893 possible reinfections with SARS-CoV-2 identified up to 30 May 2021 in England throughout the pandemic, out of nearly four million people with confirmed infections. This is equivalent to around 0.4% cases becoming reinfected.
Reinfection with SARS-CoV-2 is expected and has been previously reported. However, this data highlights that the overall risk, as detected through national surveillance, remains low. PHE is calling on everyone who is eligible for the COVID-19 vaccine to take up the offer of two doses as this will minimise the risk of re-infection. The population surveillance suggests that there were:
- 15,893 possible reinfections: A possible reinfection is identified where consecutive positive test results in the same person are at least 90 days apart. These are reinfections which have not been sequenced and so PHE cannot be completely certain they are not the same original infection.
- 478 probable reinfections: A probable reinfection is identified when sequencing of the second test sample identifies a variant known to be circulating now and/or that was not circulating at the time of the first test.
- 53 confirmed reinfections: A confirmed reinfection is where sequences are available from each episode and the sequences are genetically distinct.
Dr. Susan Hopkins, strategic director for COVID-19 at PHE said: "People are understandably concerned about whether you can catch COVID-19 more than once. While we know that people can catch viruses more than once, this data currently suggests that the rate of COVID-19 reinfection is low. However, it is important that we do not become complacent about this – it is vital to have both doses of the vaccine and to follow the guidance at all times to reduce your chance of any infection.
"We continue to learn more each day about this virus and its variants. Through continued close monitoring and research, we will understand how best we can control outbreaks and the impact this virus will have on society over the coming years."
This data shows reinfections from June 2020 up until the end of May 2021 and PHE will continue to look at the impact of vaccines and severity of illness in reinfections. Current evidence suggests that most reinfections will not cause symptoms. Work is ongoing to better understand the factors that make someone more likely to catch COVID-19 again and also the impact of vaccine status.
There is currently no evidence that the Delta variant, or any other Variants of Concern, are more likely to cause reinfection than others, but PHE says that it will closely monitor this.