A recent study by the National Institute of Communicable Diseases in South Africa reports that -
"Analysis of routine surveillance data from South Africa suggests that, in contrast to the Beta and Delta, the Omicron variant of SARS-CoV-2 demonstrates substantial population-level evidence for evasion of immunity from prior infection."
Reinfection applies to people who have been already proven to be infected with Covid 19. Those under the study were the people who had sequential positive tests at least 90 days apart.
The cohort consisted of 2,796,982 individuals with laboratory-confirmed SARS-CoV-2 who had a positive test result at least 90 days prior to 27 November 2021.
So it's a fairly large group under this study by the South African NICD and hence the data is reliable & findings should be quite accurate in a real life scenario.
Results - Identified 35,670 individuals with at least two suspected infections (through 27 November 2021), 332 individuals with suspected third infections, and 1 individual with four suspected infections.
Note - In contrast both the Beta & Delta did not show a much significant high reinfection rate. (even though the Primary infection rate was higher than the WT)
With the old variants, if you got infected once the natural immunity provided you with a lower risk of reinfection by about 80% or so. (This does not take the vaccination into account.)
It's very clear that the Omicron can evade the natural immunity. (The immunity you acquire from Covid infection itself). This study did not include those vaccinated earlier and hence how the Omicron behaves with vaccine-induced immunity remains unclear at this moment.
There will be another study for that and far too early to speculate anything yet. Also this study did not involve the severity of the disease or any hospitalization data. It dealt only with the reinfection rate.
"Analysis of routine surveillance data from South Africa suggests that, in contrast to the Beta and Delta, the Omicron variant of SARS-CoV-2 demonstrates substantial population-level evidence for evasion of immunity from prior infection."
Reinfection applies to people who have been already proven to be infected with Covid 19. Those under the study were the people who had sequential positive tests at least 90 days apart.
The cohort consisted of 2,796,982 individuals with laboratory-confirmed SARS-CoV-2 who had a positive test result at least 90 days prior to 27 November 2021.
So it's a fairly large group under this study by the South African NICD and hence the data is reliable & findings should be quite accurate in a real life scenario.
Results - Identified 35,670 individuals with at least two suspected infections (through 27 November 2021), 332 individuals with suspected third infections, and 1 individual with four suspected infections.
Note - In contrast both the Beta & Delta did not show a much significant high reinfection rate. (even though the Primary infection rate was higher than the WT)
With the old variants, if you got infected once the natural immunity provided you with a lower risk of reinfection by about 80% or so. (This does not take the vaccination into account.)
It's very clear that the Omicron can evade the natural immunity. (The immunity you acquire from Covid infection itself). This study did not include those vaccinated earlier and hence how the Omicron behaves with vaccine-induced immunity remains unclear at this moment.
There will be another study for that and far too early to speculate anything yet. Also this study did not involve the severity of the disease or any hospitalization data. It dealt only with the reinfection rate.
