Omicron Covid-19 variant can increase reinfection risk by three-fold: Study

The new super mutant Omicron variant of Covid19 can increase risk of reinfection by three times as compared to other variants of concern such as Beta and Delta according to a preliminary study by South African researchersThe study published preprint on medrxiv which means not peerreviewed yet showed that recent reinfections have occurred in individuals whose primary infections occurred across all three waves with the most having their primary infection in the Delta wavePopulationlevel evidence suggested that the Omicron variant is associated with substantial ability to evade immunity from prior infection This finding has important implications for public health planning particularly in countries like South Africa with high rates of immunity from prior infection the researchers saidWe find evidence of increased reinfection risk associated with emergence of the Omicron variant suggesting evasion of immunity from prior infection Juliet RC Pulliam from DSINRF Centre of Excellence in Epidemiological Modelling and Analysis SACEMA at Stellenbosch University South Africa wrote on TwitterThe team examined whether SARSCoV2 reinfection risk has changed through time in South Africa in the context of the emergence of the Beta Delta and Omicron variants and conducted a retrospective analysis of routine epidemiological surveillance data from 2796982 individuals with laboratoryconfirmed SARSCoV2 who had a positive test result at least 90 days prior to 27 November 2021 The results showed that 35670 individuals had suspected reinfectionsThey developed two methods to monitor signatures of changes in reinfection risk a null model with no change in reinfection risk and compared observed patterns to projections under the null modelUsing this approach we start to see reinfection numbers exceeding the projection intervals from midNovember in Gauteng and nationallyPulliam saidIn the other approach the team looked at trends in the relative hazards of primary infection and reinfectionSince early October we see a decreased risk of primary infection though this could be partially explained by vaccine rollout We see a simultaneous increase in reinfection riskWe also see a recent increase in the number of reinfections in individuals who had already had multiple suspected infections from midNovemberThese findings suggest that Omicrons selection advantage is at least partially driven by an increased ability to infect previously infected individuals Pulliam saidHowever the study does not provide information about the vaccination status of individuals in the data set and therefore the researchers said they cannot conclude whether Omicron also evades vaccinederived immunity and the potential implications of reduced immunity to infection on protection against severe disease and deathImmune escape from prior infection whether or not Omicron can also evade vaccine derived immunity has important implications for public health globally but there is still a lot we dont know Pulliam saidThe team aims to next include quantifying the extent of Omicrons immune escape for both natural and vaccinederived immunity as well as its transmissibility relative to other variantsAlso Read Bhopal Gas Tragedy 37 years on children then not born scarred foreverThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoever