There are not yet complete data on the so-called delta variant, formerly known as the Indian mutation, but there are indications that it is more contagious.

Compared with the alpha variant, also called the British mutation, it can be fifty percent more contagious, according to Jan Albert, professor of microbiology and infection control expert at Karolinska Institutet.

- There is a risk that we will see more spread of infection, but hopefully at a comparatively low level.

There is full focus on trying to find cases and limiting the spread of infection around them right now, says Jan Albert. 

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In the clip, Jan Albert sorts out three question marks around the delta variant.