Coronavirus in kleur

The BA.5 variant of the coronavirus SARS-CoV-2 was detected for the first time in the Netherlands this week. According to the WHO, this new variant does not appear to cause more serious illness or to be more contagious than the BA.2 variant that is currently most common in the Netherlands.

Subtypes of Omicron

Earlier this month, the World Health Organisation (WHO) announced that it had found two new subtypes of the Omicron variant: BA.4 and BA.5. These variants had mainly been found in southern Africa, but also in Germany and Denmark. In an especially in-depth investigation conducted this week in conjunction with Saltro, the BA.5 variant was also found in the Netherlands. This subvariant was detected in a sample taken on 11 April 2022. So far, neither of these variants has been found in pathogen surveillance (random sampling conducted by RIVM every week). The variant does not seem to have spread widely in the Netherlands yet.

Little difference

Mutations in the genetic material of the virus have been identified in the BA.5 variant. These mutations include changes in the spike protein, which is the protein responsible for bonding in the respiratory system. This is also the main target of the antibodies that your immune system uses to recognise the coronavirus. 

Not much information is available about this new variant yet. The WHO has found no difference in virulence or speed of infection. Researchers are still investigating the extent to which these mutations can enable this variant to evade the defences of the immune system. This would be possible if the mutations cause the immune system not to recognise this variant, or to recognise it less well (immune escape).


Do you have symptoms that could indicate a SARS-CoV-2 infection, or are you unsure if you might have COVID-19? Then use a self-test and stay home if you test positive for COVID-19.