The New COVID Variant EG.5

The World Health Organization has declared a new sub-variant of Covid called EG.5 - unofficially named "Eris" - a variant of interest.

What is EG.5?

Ever since it first emerged, Covid has been mutating or shape-shifting and becoming incrementally different. The new genetic versions that keep appearing are called variants. EG.5 is one of more than 600 Omicron subvariants of Covid that are currently circulating. Omicron (B.1.1.529) was a variant of SARS-CoV-2 first reported to the World Health Organization by the Network for Genomics Surveillance in South Africa on 24 November 2021.

EG.5 was first seen in February 2023 and cases have been increasing steadily. It has been dubbed Eris on social media - also the name of a goddess in Greek mythology.

EG.5 may sound like a whole new flavor of the virus, but it’s not; it’s a spinoff of the XBB recombinant strain of the omicron family. And it represents another incremental tweak to the virus rather than a major evolutionary leap like the original omicron strain.

Compared with its parent XBB.1.9.2, it has one extra mutation to its spike, at position 465. The 465 mutation is present in about 35% of coronavirus sequences reported worldwide.

EG.5.1

EG.5.1 is a sub-strain of Omicron XBB and has additional mutants on the spike protein S:F456L and S:Q52H. Within the EG.5 lineage, the subvariant EG.5.1 has an additional spike mutation Q52H and represents 88% of the available sequences for EG.5 and its descendent lineages. Studies have shown that its speed of transmission is 45% more than XBB.1.16.

EG.5.1 cases have been climbing in many countries including China, the United States and the United Kingdom. Although no evidence suggests that EG.5.1 causes more severe disease than other Omicron variants, it is more transmissible and potentially vaccine-resistant. 

As with Omicron, the most common symptoms of EG.5.1 include runny nose, headache, fatigue (mild or severe), sneezing and sore throat. EG.5.1 is not a significant issue of itself – more like the first step on the ladder to the variant that will cause the next wave.

The virus has changed, incrementally, making EG.5.1 more transmissible. Some tests suggest it can evade our immune systems more easily than some circulating variants but this has not been translated into people becoming more seriously ill. Experts around the world will continue to monitor the sub-variant and assess its impact, particularly as schools and universities reopen.

As with other Covid variants, the risk of serious illness remains highest for people who are elderly or have significant underlying health conditions.

Where is EG.5 Spreading?

According to the WHO, infections have been reported in 51 countries, including China, the US, the Republic of Korea, Japan, Canada, Australia, Singapore, the UK, France, Portugal and Spain.

Aug 9 - The World Health Organization on Wednesday classified the EG.5 coronavirus strain as a "variant of interest" but said it did not seem to pose more of a threat to public health than other variants.

GISAID , the Global Initiative on Sharing All Influenza Data, previously the Global Initiative on Sharing Avian Influenza Data, is a global science initiative established in 2008 to provide access to genomic data of influenza viruses. The database was expanded to include the coronavirus responsible for the COVID-19 pandemic as well as other pathogens. The database has been described as "the world's largest repository of COVID-19. 

As of 7 August 2023, 7354 sequences of EG.5 have been submitted to GISAID from 51 countries. The largest portion of EG.5 sequences are from China (30.6%, 2247 sequences). The other countries with at least 100 sequences are the United States of America (18.4%, 1356 sequences), the Republic of Korea (14.1%, 1040 sequences), and Japan (11.1%, 814 sequences).

Globally, there has been a steady increase in the proportion of EG.5 reported. During epidemiological week 29 (17 to 23 July 2023), the global prevalence of EG.5 was 17.4%. This is a notable rise from the data reported four weeks prior (week 25, 19 to 25 June 2023), when the global prevalence of EG.5 was 7.6%. Based on the available evidence, the public health risk posed by EG.5 is evaluated as low at the global level, aligning with the risk associated with XBB.1.16 and the other currently circulating VOIs. 

While EG.5 has shown increased prevalence, growth advantage, and immune escape properties, there have been no reported changes in disease severity to date. While concurrent increases in the proportion of EG.5 and COVID-19 hospitalizations (lower than previous waves) have been observed in countries such as Japan and the Republic of Korea, no associations have been made between these hospitalizations and EG.5. However, due to its growth advantage and immune escape characteristics, EG.5 may cause a rise in case incidence and become dominant in some countries or even globally. 

Variants of Interest 

The WHO defines a variant of interest as one that has genetic changes that could increase its transmissibility, virulence, its ability to evade vaccines, be treated with drugs or detected via current testing methods - as well as already demonstrating a “growth advantage” over other circulating variants. The current variant of interest list includes EG.5 and two other Omicron cousins - XBB 1.5 and XBB 1.16 (the latter sometimes referred to as Arcturus). 

Symptoms

Experts say there is no evidence to suggest EG.5 causes any new Covid symptoms. Symptoms of Covid can include fever, continuous cough, change in sense of taste or smell, fatigue, runny nose and sore throat.

Prevention Tips

Applying basic health and hygiene practices, like handwashing, wearing masks and increasing space and distance. Staying up to date with COVID-19 vaccines, improving ventilation, getting tested for COVID-19 If needed, staying home if you have suspected or confirmed COVID-19, seeking treatment if you have COVID-19 and are at high risk of getting very sick, and avoiding contact with people who have suspected or confirmed COVID-19.