Vaccine efficacy may be reduced by the latest mutation, dubbed E484K.
In the past three months, Covid-19 has acted like a shapeshifter, mutating and adapting and throwing new challenges at the global scientific community.
The UK Covid-19 variant, dubbed VOC 202012/01 or B.1.1.7, quickly became responsible for nearly 50 per cent of cases in the UK, before spreading around the world. Out of that variant, a new variant has evolved, which is far more contagious and transmissible. In an ironic twist, while the newest variant is not more lethal, in the grand scheme it’s higher transmissibility has a higher chance of causing more deaths in a population because it causes more infections than the original Covid-19 virus.
The variant’s first mutation affected its ‘spike protein’, the receptor that allows the virus to latch on to cells. The virus has undergone a more recent mutation, described as E484K in a United Kingdom public health briefing document on February 1 2021.
The latest E484K mutation was also seen in the South African coronavirus variant (B.1.351), and in Brazil (P.1). In South Africa, it was found to reduce the effectiveness of covid-19 vaccines. All three variants have also been found in the United States.
Public Health England reports that the latest mutation in the UK B.1.1.7, dubbed the “escape mutant,” may aid the virus in evading the body’s antibodies after a vaccine.
In one horrific experience in Brazil, after the virus was downplayed by Jair Bolsonaro, the city of Manaus was hit hard as people failed to practice precautionary social distancing measures. Scientists estimate that nearly 75 percent of the population may have been infected. As cased dropped, many believed the city had developed herd immunity against covid-19.
It didn’t do them any good. Within months cases began to climb again and hospitals were quickly overwhelmed. The virus had picked up the E484K ‘escape mutation’, in addition to 17 other changes from its parent virus.
Unlike the N501Y mutation that made the UK variant more contagious, the E484K mutation switches a negatively charged acid for a positive one, making it incredibly difficult for a bodies antibodies to identify and latch onto the virus, similar to reversing a magnet’s polarity.
For antibodies that are custom built by the body to hunt down a specific threat based on its history of previous infections, that could be trouble for vaccines and herd immunity alike.
But seeing the same kind of genetic mutation in the UK’s variant does not mean it will necessarily have the same effect. The effect of any given mutation is largely determined by the overall genetics of the virus, and is also affected y by any mutation the virus may already be carrying.
Vaccine effectiveness is a deeply concerning issue in the face of viral mutations. On January 29, Johnson and Johnson reported that their vaccine was only 72 per cent effective in the US, and only 57 per cent effective in South Africa. The new South African covid-19 is already dominant in the country, and is likely responsible for the disparity in figures.
Novavax also reported that its vaccine was only 85 per cent effective against the UK variant, and only 50 per cent effective against the South African variant.
While variants are named after the countries they are found in, they may actually have originated elsewhere. Instead, they’re named after the countries they’re first genetically sequenced in.
With over 103 million coronavirus infections and nearly 2.3 million deaths worldwide, one thing scientists are certain of is the presence of more variants that have yet to be identified and more mutations that are still underway.
The identification of the UK covid-19 variant was largely possible due to a ‘robust genomic surveillance effort’ in the United Kingdom, while discovery lags in other regions of the world.
In a chilling release that underlines the risks viral mutations pose, the World Health Organization reports that since the discovery of the UK variant on January 25 it has already spread to 70 countries around the world.