Omicron: Re-infection Possible as per Preliminary Study

It has been over ten days now since, Omicron, the latest variant of concern of the pandemic virus emerged. The world is scrambling to understand the degree of threat it faces. One of the primary concerns has been to decipher whether the new variant of concern can cause re-infection, that is infecting those who have once got the bout of infection already.

Re-infection is a preliminary hint that the new variant has the ability to evade natural immunity gathered from the previous infection.

The latest study conducted in South Africa has brought up some ominous data hinting at the point that Omicron could evade our immunity. However, this is a rapid analysis study and it is yet to be said a definitive one. Alongside, it needs to be mentioned that the preliminary data does not say anything about the evasion of vaccine protection. Notably, the WHO (World Health Organisation) still writes in its update that the confirmatory experiments are undergoing and has not said anything conclusively.

The new variant has already spread to more than 30 countries. Scientists in South Africa, where the presence of the new variant was first reported analysed over 36,000 suspected re-infections and looked for changes in re-infection rate, if there is any, throughout the pandemic. Notably, they showed that there was no risk of a surge of re-infection during the waves caused by the Delta or the Beta variants.

Interestingly, this was observed despite some laboratory studies saying that the Beta and Delta variants had the potential to evade immunity.

But, now they are seeing a surge in re-infection cases. Although they have not tested each individual who suffered from COVID-19, the timing suggests that the new variant is the main driving force, the scientists said.

The study by scientists in South Africa has been published in the preprint server medRxiv on December 2. The estimates suggest that Omicron could be twice as likely to cause re-infections in comparison to earlier variants.

Juliet Pulliam, the lead author of the study and a professor at Stellenbsoch University commented on the findings as—“These findings suggest that Omicron's selection advantage is at least partially driven by an increased ability to infect previously infected individuals.” However, this is still only preliminary and a small piece of a greater puzzle regarding the variant.

Questions still remain about how much waning immunity can be a factor along with the concern of the extent to which any variant would be able to take off now. Moreover, this was a rapid analysis and with the high burden of HIV in the country, it can also be a factor to suppress the overall immunity (HIV suppresses immunity). So, whether this data can be extrapolated to the rest of the world, remains a question.

Laboratory studies seeking information on how well antibodies can attack the variant are still in the process and are expected to give results in the coming week.

Importantly, South Africa has a low record of 24% of the population getting fully vaccinated. The researchers mentioned that their results can also have implications for other such countries. However, Juliet Pulliam said that they cannot say anything about the vaccine evasion capability of Omicron.

Paul Hunter, professor at the University of East Anglia commented on this aspect as—“The implications of this paper are that Omicron will be able to overcome natural and probably vaccine-induced immunity to a significant degree. But, the degree is still unclear - though it is doubtful that this will represent a complete escape.”

Most of the scientists however believe that vaccines, even if less effective from preventing from getting infected, will still hold their capacity of preventing severe diseases and deaths better.