One of the latest coronavirus variants to raise concern is the Delta Plus. But what is it and why is it a potential problem in the fight to suppress the virus?
What is the Delta Plus variant?
Delta Plus is simply the Delta variant with an additional mutation called K417N. There are at least two separate groups of the variant and these are known as AY.1 and AY.2. The first of these, AY.1, appears to be the most globally widespread.
Where did the Delta Plus variant come from?
The first case was observed in India on 5 April 2021, but the variant has now spread to many countries. Cases have been found in the UK, the US, Canada, Portugal, Poland, Switzerland, Russia, Turkey, Japan and Nepal. It was briefly, and unofficially, described as the Nepal variant when it first came to light because it was found in 13 people who travelled from Nepal to Japan. Where it originally emerged is unclear.
The first UK case of Delta Plus was recorded on 28 April 2021. So far numbers have remained small. As of 18 June, Public Health England had identified 36 confirmed and two probable cases of AY.1 infection in England. No AY.2 has been detected in the country.
Why is it causing concern?
The same K417N mutation is found in the Beta variant first detected in South Africa. The Beta variant is a concern because evidence suggests it is partially resistant to vaccines based on the original pandemic virus, and to immunity gained from previous Covid infection. The K417N mutation is believed to be part of the reason the Beta variant can evade vaccines to some degree, so when the highly transmissible Delta variant acquires the mutation, scientists are bound to pay attention.
At the moment, vaccines seem to perform well against the standard Delta variant, particularly after two jabs, but public health authorities are concerned that the K417N mutation could dent vaccine protection, or immunity gained from previous infection with an older form of the virus.
Is it more transmissible than Delta?
With so few cases reported, scientists know very little about how fast the variant spreads, the severity of disease it causes, and how much it may evade immunity. Given that numbers have remained small in the regions it’s been detected, it may not be more transmissible than the “original” Delta variant. It will take more data to know for sure.
