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According to the WHO, preliminary evidence suggests there may be an increased risk of reinfection with 'Omicron' - people who have previously had COVID-19 could become reinfected more easily with this variant.
It is not yet clear whether 'Omicron' is more transmissible (more easily spread from person to person) compared to Delta and other variants. For now, RT-PCR tests can detect the strain.
The WHO is working with technical partners to understand the potential impact of this variant on vaccines.
It is not yet clear whether infection with 'Omicron' causes more severe disease. There is currently no information to suggest that symptoms associated with Omicron are different from those from other variants.
Preliminary data suggests increased hospitalisation in South Africa, but this may be due to increasing overall numbers of people becoming infected, rather than a result of specific infection with 'Omicron'. Initial reported infections were among university studies - younger individuals who tend to have milder symptoms - but understanding the level of severity of the 'Omicron' variant will take days to several weeks.
See the full briefing here: