COVID-19 needs no introduction to the current world. We all have been there where the Movement Control Order (MCO) started in 2020 and more than one MCO for sure throughout the year until the Recovery MCO (RMCO) in 2021. These years were the hardest for everyone especially those directly affected by the virus and have symptoms of COVID-19. Fortunately, at least for now, COVID-19 is under control. However, this does not mean that there is no case at all in the country. We can breathe better and live normally knowing that COVID-19 is less likely to be spread as it was back when it first started. This could be from the vaccination rules that help to reduce the severity of COVID-19 and provide protection against the virus. This does not only lead to low numbers of the infection but also reduces the number of people getting severely ill by the virus.
You might have heard about the many variants of COVID-19 virus throughout the past years. Virus in general tends to mutate easily and every variant of the virus is different in structures. Differences in the structure of the virus lead to the different function or ability of the virus to invade humans. The human cells lack proofreading skills that make the virus mutations more rapidly than human cells do and the virus becomes much better at evading the human’s immune system. Thus, the newest COVID variant known as EG.5 or known as Eris is certainly intriguing for us to learn about.
The World Health Organization (WHO) said the new omicron subvariant EG.5 or nicknamed as ‘Eris’, reignited the talk about vaccines and speculations of returning from the pandemic. Although more than 3 years of the COVID-19 pandemic and the WHO ended the global public health emergency in May 2023, WHO has stated that the virus leading to COVID had not been fully defeated. This translates to the possibility of the continuous virus circulating the world and may see the emergence of new and more dangerous variants.
Now with the new COVID variant of EG.5, we are back to square one in terms of understanding how the virus will affect us humans. At time of writing, this new variant is classified as a variant of interest and not a variant of concern. If a variant is placed under the variant of concern, this can be a significant influence on the way virus spread as there is more risk for it being contagious and an increased number of infections, or an increase in severe form of illness and mortality rates.
EG.5 variant is similar to the mutations of XBB.1.5. It is a descendant lineage of XBB.1.9.2. The key difference is that EG.5 carries additional amino acid mutation in the spike of protein that sits on the surface of the virus. This structure alone might have helped EG.5 to evade neutralisation by antibodies in body fluids or known as immune escape properties.
Symptoms of Eris are reported to be the same as past variants such as fever, cough, sore throat, fatigue, runny nose and changes in taste or smell. There are no severity changes of symptoms although EG.5 does show an increase of COVID 19 cases and its immune escape properties.
The ability of EG.5 to evade neutralisation with antibodies means more people are likely to be infected with it, although they have been previously vaccinated against COVID-19 and/or infected with earlier versions of the Omicron variant. Neutralising antibodies are molecules that bind to viruses and destroy it before it is able to invade cells and starts replicating in number. It is an important early line of defence against infection.
Thus, the ability of EG.5 to partially evade antibody neutralisation means COVID-19 vaccines they have received previously are less likely to protect people against this infection. It is important to note that even if it is likely to not fully protect against EG.5, at the very least, being fully vaccinated against COVID-19 will provide a stronger immune system against the EG.5 compared to no vaccination at all. This means it can prevent severe disease, hospitalisation and death. Booster vaccination will increase antibody level and make people less susceptible to infection. It is important to get booster vaccination if a person is susceptible to get severe COVID-19 due to ageing or other underlying health conditions.
WHO sees potential for EG.5 to cause a rise in case incidence and become dominant in some countries or even globally. This is due to the growth advantage and its immune escape characteristics evading the antibody neutralisation. Rise in cases can be explained by the fact that people living in the Northern Hemisphere are in the midst of summertime COVID waves. People tend to stay in air-conditioned spaces during the heated summer. This makes transmission of the COVID more easier due to the virus presented in the closed space and the recycled airflow.
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