You thought COVID was over? COVID XEC is coming!

As we enter the fall, a new variant of the COVID-19 virus, XEC, is spreading. The XEC variant was first reported in Berlin, Germany in late June, and has since been confirmed in Europe, the United States, Asia, and around the world. In the United States, XEC cases have been reported in 25 states. There is a prevailing analysis that the new variant virus, XEC, will become a major global variant after the fall. This is because of its high contagiousness. Let's find out what COVID XEC is, the early infection symptoms, and the genetic mutations and transmissibility of COVID XEC.

What is COVID XEC? Why should we be concerned?
The genetic mutations and transmission of COVID XEC
Early symptoms: What’s different this time?
Who is at the greatest risk?
Is this an extension of the pandemic or a new era?

What is COVID XEC? Why should we be concerned?

COVID XEC is a new, highly contagious variant of the SARS-CoV-2 virus that causes COVID-19. The COVID XEC variant is a reassortant of two omicron sub-variants, KP.3.3 and KS.1.1. The biggest concern about XEC is its rapid spread. XEC is spreading rapidly and has been detected in several countries, including the United States and several European countries, and accounted for approximately 5.7% of COVID infections in the United States by the end of September 2024.

To date, there is no evidence that XEC causes more severe disease than other recent variants.

The good news is that current COVID vaccines, especially the updated vaccines for 2024-2025, are expected to provide some level of protection against XEC. While the vaccines may not be perfect for all mutations, they still provide significant protection, especially against severe outcomes. Experts recommend getting vaccinated to ensure protection against this and other variants.

The genetic mutations and transmission of COVID XEC

COVID XEC is a highly transmissible variant that is a recombinant of two highly transmissible Omicron strains, KS.1.1 and KP.3.3. In terms of genetic mutations, XEC has a unique set of spike protein mutations in both KP.3.3 and KS.1.1, plus at least one additional mutation that is not found in either parent strain. 

The genetic makeup of XEC suggests that it is highly transmissible, but the severity of the disease remains consistent with Omicron subvariants. The most commonly reported COVID-19 variant in the United States is currently KP.3.1.1, a member of the Omicron strain that has been the dominant strain in the United States since late July. According to the most recent data from the Centers for Disease Control and Prevention (CDC), from September 1 to 14, 52.7% of positive infections were from this variant.

Early symptoms: What’s different this time?

The initial symptoms of COVID XEC are generally similar to those of other Omicron substrains, with no major differences reported to date. However, one of the main concerns with XEC is its increased transmissibility. While symptoms remain largely consistent, concerns are growing that XEC can spread rapidly and cause more infections, especially as it occurs concurrently with other respiratory viruses during the cold season. Common symptoms include:

- Cough

- Congestion or runny nose

- Sore throat

- Fatigue

- Headache

- Fever or chills

- Shortness of breath

- Loss of taste or smell (less common with newer strains)

Who is at the greatest risk?

Individuals at highest risk for COVID XEC variants include:

Older adults 65 years of age and older: People 65 years of age and older are at higher risk for severe illness from COVID-19, including the XEC variant.

Immunocompromised individuals: People with weakened immune systems, such as those receiving cancer treatment, those with HIV, or those taking immunosuppressant medications, are more susceptible to severe outcomes if they become infected with XEC.

People with chronic medical conditions: People with preexisting medical conditions, such as diabetes, heart disease, lung disease, or obesity, are at higher risk for complications. These conditions can make it harder for the body to fight off infections.

Unvaccinated individuals: People who are unvaccinated or who have not received the updated COVID vaccines for 2024-2025 are at higher risk for infection and severe illness. Current vaccines are not perfect, but they provide significant protection against severe outcomes.

Pregnant women: Pregnancy can increase the risk of severe illness from COVID-19, and infection during pregnancy can cause complications for both mother and baby.

Is this an extension of the pandemic or a new era?

Many experts believe COVID-19 is moving into a phase where it becomes more like the flu, circulating seasonally and becoming more transmissible. The XEC variant is highly contagious, but has not been shown to cause more severe disease than previous Omicron strains, so it is considered one of the seasonal threats like the flu.

Updated COVID vaccines for 2024-2025 are designed to provide protection against circulating variants, including XEC. These vaccines, like the flu vaccine, will be released seasonally, making it difficult to completely prevent infection, but will help mitigate severe outcomes. XEC is concerning because of its transmissibility, but it will not signal a new pandemic era. Instead, we are likely witnessing the coronavirus transition into a new, more manageable endemic phase.

Source:

1. Endemic Covid: Is the pandemic entering its endgame?. https://www.bbc.co.uk/news/health-59970281.

2. The next pandemic: not if, but when - Harvard T.H. Chan School of .... https://www.hsph.harvard.edu/news/features/next-pandemic-not-if-but-when/.

3. What to know about the new covid-19 XEC variant. https://www.newscientist.com/article/2448924-what-to-know-about-the-new-covid-19-xec-variant/.

4. New XEC COVID Variant On The Rise: What Are Its Symptoms? - TODAY. https://www.today.com/health/coronavirus/new-xec-covid-variant-symptoms-rcna171502.

5. 3 Things to Know About XEC, the Latest COVID Strain. https://www.yalemedicine.org/news/3-things-to-know-about-xec-the-latest-covid-strain.