Can you get Omicron twice?

Risk of reinfection ‘more than five times higher’ than with Delta variant, say experts

A worker at a Covid testing site
(Image credit: Oli Scarff/AFP via Getty Images)

Millions of people in the UK have been infected with Covid-19 in recent weeks, with the majority contracting the Omicron variant that first took hold in late November.

Now, having recovered from the virus, many are asking whether it’s possible to get infected with Omicron again.

As it has been less than two months since the first Omicron case in the UK was reported, there is no data yet that proves that patients can be reinfected with this same variant. However, a spokesperson for the UK Health Security Agency (UKHSA) told the i news site that it was “definitely possible”.

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It is certainly possible to get Covid twice, with Public Health England saying that reinfection is mainly reported “from around six months after the first infection”.

As people can show up as positive on a PCR test for up to three months after their first test, most public health bodies define reinfection as “two positive test results for the same individual 90 or more days apart”, said the i. Therefore, the data on Omicron reinfection rates is not available yet, as it has been fewer than 90 days since the first case was reported.

General reinfection risk ‘five times higher’

Scientists did see a lot more people being reinfected with Omicron after previously having another variant such as Beta or Delta.

An early study of 36,000 suspected reinfections in South Africa estimated that Omicron could be “twice as likely to cause a re-infection than earlier variants”, said the BBC. One of the researchers, Professor Juliet Pulliam from Stellenbosch University, said the findings suggested that Omicron could have an “increased ability to infect previously infected individuals”.

A study a few weeks later by Imperial College London put the risk of reinfection with the Omicron variant at more than five times higher than with Delta.

Study lead Professor Neil Ferguson said that the research provided “further evidence of the very substantial extent to which Omicron can evade prior immunity given by both infection or vaccination”, Reuters reported.

In January, scientists called for reinfections to be included in Covid figures for the UK, warning that up to 15% of Omicron cases could be people who have had the coronavirus before.

‘Don’t have sufficient data’

It’s important to remember that both the South African and Imperial College studies were carried out without much data to work from. Clive Dix, former chair of the UK Vaccine Taskforce, said the conclusions were “based on making assumptions about Omicron where we still don’t have sufficient data”.

Dr Allison Arwady, Chicago’s public health commissioner, said that “unofficially” she thought it was “unlikely” for someone who had been infected with Omicron to get reinfected with Omicron within the next few months, NBC Chicago reported.

However, she added that she was “less confident in that statement than I would have been for prior variants, given what we’ve seen”.

Speaking during a Facebook Live on 18 January, Arwady noted that those who are reinfected with the virus should “take some consolation” in the fact that they would have developed “a little bit of a booster” as a result of it, on top of any Covid vaccination and/or booster jab.

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