Why the COVID-19 variants are so dangerous and how to stop them spreading - The Conversation AU

These include a variant called B.1.1.7 that has spread very quickly within the UK, with other new variants now observed in South Africa and Brazil.

But the new variant detected in the UK is more transmissible than the original virus that was dominant in 2020.

The good news is it does not cause more severe illness or have a higher fatality rate than the original variant.

The average number of people an infected person with COVID-19 passes the virus on to — the so-called R number — is 40%-70% higher with B.1.1.7 than the original variant.

The number of cases of the B.1.1.7 variant has risen rapidly relative to the original variant.

And they estimated a person with the new variant infects 56% more people on average than a person with the original variant.

Together, this provides strong evidence the B.1.1.7 variant is between 40% and 70% more transmissible than the original variant.

The variants found in South Africa and Brazil share some of the same mutations as the B.1.1.7 variant.

The new variants have been detected in many countries, including in people in New Zealand’s managed isolation facilities.

The more transmissible variants arriving at the New Zealand border increase the risks to these workers, who in turn have a higher chance of passing the virus onto others in the community, amplifying the risk of a community outbreak.

The new variants spread in the same way as the original one: through close contacts between people, especially in crowded or poorly ventilated environments.

But any variant that is more transmissible has a higher R number.

If we had a similar outbreak with the new variant, R could be 50% higher which would mean it is above 1