Could the Beta variant be wiped out by the Delta strain?

Cases of the once prevalent Beta variant have been declining over 2021, after the emergence of the highly contagious Delta COVID variant.

Scientists have predicted that the Beta coronavirus variant will soon be wiped off the map as cases of the Delta strain have continued to surge globally.

Cases of the Beta variant are declining worldwide

During the pandemic, countries with the available resources have been regularly genome sequencing coronavirus cases in order to keep track of new and developing strains. This data is then shared with the Global Initiative on Sharing All Influenza Data, also known as Gisaid.

Not all data is shared to the publicly available database, and many countries lack the equipment to carry out genome sequencing. However, the available information shows that fewer countries are reporting cases of the Beta variant - the concerning strain that emerged in South Africa late last year.

Gisaid data shows that just 1,956 cases of the Beta variant were recorded between the 15th and the 21st of March out of a total of 91, 644 sequenced cases, suggesting that the Beta variant accounted for 2% of the world’s COVID cases. While this number is likely to be much higher on account of inaccessible sequencing technology in most countries, the number of Beta variant cases continued to fall. According to the database, by the 11th of July, just 0.4% of the world’s cases were caused by the Beta variant.

Aside from the overwhelming trend of declining Beta cases, countries such as South Africa, France and Spain have all seen a small increase in the variant in recent weeks. Despite this, scientists are still confident that the Delta variant is edging out the once prominent Beta strain and will eventually force it into extinction. Aris Katzourakis, a professor of evolution and genomics at Oxford University, spoke to the Independent:

Beta is really good at escaping the vaccines but unlike Alpha and Delta, it doesn’t have - or at least nobody has demonstrated yet - a particularly strong transmission advantage. So, it’s likely to be outcompeted by both Alpha and Delta in vaccine-naive populations. It’s not surprising that it is happening.

Beta variant faces competition from Alpha and Delta

The Beta variant once topped the charts for the most concerning COVID strain. Otherwise known as the B.1.351 strain, the Beta variant contained several mutations to its protein spike - the part of the virus responsible for attaching to human cells.

The mutation classed as E484K also allowed the Beta variant to evade the immune system to some degree, rendering the AstraZeneca vaccine inefficient at protecting against infection.

However, the Beta variant has struggled to spread as far and as fast as the Alpha and Delta strains, robbing the variant of any chances of a dominant status.

Professor Paul Hunter, an expert in health protection and infectious diseases at the University of East Anglia, also spoke to the Independent, detailing that viruses that jump from animal to human often begin with many variants that narrow down over time to an ‘ideal’ strain:

Once it’s got a combination which is the best fit - think of it as a key in the lock - then that variant takes over and effectively excludes all the other variants. After that point you still get some evolution but it’s a lot slower. I think the Beta variant was one of these half-hearted attempts at getting the best fit for the key.

Professor Hunter went on to exclaim that in as little as a year, the Beta variant could be effectively extinct.

The Delta variant has a viral load 300 times higher than original COVID strain The Delta variant has a viral load 300 times higher than original COVID strain