The Omicron variant has been causing a surge in the coronavirus disease (Covid-19) infection across the world. The number of hospitalisations is less, but the spread of infection is faster, owing to a high number of mutations the Omicron possesses.
This begs a question: Can the Omicron variant reinfect a person? Health experts and the World Health Organization (WHO), which keeps an eye on the new and emerging variants of the constantly mutating coronavirus, have said that the possibility of reinfection is high.
In a note published on the Omicron variant, the WHO said that the variant can evade previous immunity in people and can still infect those who have had Covid-19 in the past. It sounded an alarm for people who are unvaccinated, and those who were vaccinated many months ago.
"Individuals who have recovered from Covid-19 are 3 to 5 times more likely to be reinfected with Omicron compared to Delta," the WHO said in the note released on its website last month.
It, however, added that there is still no proof that Omicron causes more severe disease than the Delta variant, which led to a devastating second wave of infection last year.
The WHO said that the virus has been transmitted mostly among adults in their 20s and 30s, spreading initially in large cities and in clusters associated with social and workplace gatherings.
However, some studies have confirmed the silver lining of the Omicron variant. News agency Bloomberg reported earlier this week that a combination of widespread immunity and numerous mutations have resulted in a virus that causes far less severe disease than previous iterations.
The Bloomberg report was based on the ongoing studies being conducted on Omicron, including in South Africa where the variant first emerged.
One of the crucial factors which makes Omicron less virulent is that it does not infect the lungs as easily as the previous variants. One such study was published by a consortium of Japanese and American scientists, who experimented on mice and hamsters. Another study in Belgium reported similar outcomes in hamsters, which experienced severe illness with previous mutations of the virus.