New, more infectious SARS-CoV-2 variant does not cause worse symptoms

Research shows that a new variant of SARS-CoV-2, which is now the dominant form of the virus, is more infectious in cell cultures. However, clinical data suggest that the variant does not cause more severe illness.

All viruses mutate, and the new coronavirus, SARS-CoV-2, is no exception. As an RNA virus, the new coronavirus is highly prone to mutation, partly because the replication enzymes of RNA viruses make more mistakes when copying genetic material.

Although the virus is mutating slowly, scientists had raised concerns that some of the mutations could make the virus more infectious.

One mutation in particular – D614G – has been a focus of concern, as it occurs in the spike protein of the virus. This site is important because it is the spike protein that attaches to host cells and eventually leads to their infection.

D614G refers to a change in the amino acid (from D to G) in position 614, and people may also refer to it as the G614 variant.

Over a month, the G614 variant became the dominant form of SARS-CoV-2 around the world. There is evidence of G614 mainly in Europe in February, and by April, it had overtaken the original D614 form worldwide.

The rapid domination of this variant suggests that it may give the virus an advantage, increasing its infectiousness. To evaluate this, a team of researchers led by Los Alamos National Laboratory (LANL) near Santa Fe, NM, tracked global patterns of the G614 variant and performed experiments in cells.

Their results confirmed that the G614 variant is more infectious but, fortunately, is not associated with a more severe form of COVID-19.

The team’s findings appear in the journal Cell.

 

Tracking mutations

The G614 variant first piqued the study team’s interest in April, when they noticed a repeated pattern across the globe.

Bette Korber, a theoretical biologist at LANL and lead author of the study, explains, “All over the world, even when local epidemics had many cases of the original form circulating, soon after the D614G variant was introduced into a region, it became the prevalent form.”

Korber’s team developed a bioinformatics tool to identify mutations in the spike protein that were becoming more common, using the SARS-CoV-2 sequence database hosted by GISAID. Tens of thousands of SARS-CoV-2 genetic sequences are available on GISAID, which has become the standard for sharing sequences among COVID-19 researchers.

Their analysis showed that before March 1, the G614 variant was present in 10% of sequences. By the end of the month, it represented almost 70% of sequences in the database.

The shift to G614 forms of the virus occurred across the world, first in Europe and then in North America and Asia. It occurred at the national, subnational, county, and city levels.

 

Higher infectiousness confirmed in cells

The geographical data clearly indicate that the G614 variant is more infectious. To confirm this in vitro, the researchers performed cell studies using forms of viruses with either the original (D614) or new (G614) variant of the spike protein.

They found that viruses with the D614G mutation were significantly more infectious — in some cases, by more than nine times.

By analyzing real-life data from almost 1,000 COVID-19 patients, they also showed that the G614 variant is associated with a higher viral load.

This finding is based on the fact that less viral genetic material was necessary to perform a diagnostic test in people with the G614 form of the virus.

 

Reassuring clinical data

However, there is some good news here. Despite its association with a higher viral load, the new variant of SARS-CoV-2 does not appear to be associated with worse outcomes.

“[E]ven though patients with the new G virus carried more copies of the virus than patients infected with D, there wasn’t a corresponding increase in the severity of illness,” explains co-author of the study Prof. Erica Ollmann Saphire, from the La Jolla Institute for Immunology, CA.

The researchers found no link between the new G614 variant and disease severity, which they assessed using data on hospitalization for COVID-19.

Although the new variant of the virus does not appear to cause more severe symptoms, it is more infectious, and the authors recommend continued measures for protection, including mask wearing.

Source: medicalnewstoday

 

YOU SHOULD NOT MISS THESE HEADLINES FROM NIGERIAN TRIBUNE

PRINCIPALS of secondary schools nationwide under the aegis of All Nigeria Confederation of Principals of Secondary Schools (ANCOPSS) have also expressed surprise over Minister of Education, Mr Adamu Adamu’s announcement on Wednesday withdrawing all the SS3 students in all the 104 Federal Government colleges… Read Full Story
AS the investigation into the corruption allegations levelled against the embattled acting chairman of the Economic and Financial Crimes Commission (EFCC), Ibrahim Magu, entered its fourth day on Thursday, the secretary of the anti-graft agency, Olanipekun Olukoyede and some of its directors have appeared before the panel … Read Full Story
President Buhari will on Friday sign into law the revised 2020 budget of N10.8 trillion passed by the National Assembly last month… Read Full Story
Ten of the aspirants who picked the All Progressives Congress (APC) Expression of Interest and nomination form ahead of its July 10 primary in Ondo State may boycott the election… Read Full Story
The Speaker of Zamfara State House of Assembly, Alhaji Nasiru Mu’azu has said the ongoing renovation works in the assembly complex will not hinder the lawmakers from passing laws that will be beneficial to the… Read Full Story
Pan- Yoruba socio-political group, Afenifere, has kicked against Federal Government’s decision to withdraw Nigerian students from writing this year’s examinations conducted by West African Examination Council (WAEC), on account of ravaging COVID-19, describing such move as amounting to the country being burdened… Read Full Story
FOR much of his life, Abdul-Halim al-Akoum stashed away cash in hopes of one day travelling from his Lebanese mountain village to perform the hajj, the pilgrimage to Mecca that all Muslims who can are obliged to make once in their lives. He was all set to go this year until the coronavirus pandemic forced Saudi Arabia… Read Full Story
Olusina Ajayi Olatinwo, who is over 60 years of age, recently got united with his family in Ibadan, after spending 21 years in different prisons across the South-West, on a wrongful conviction that led to a death sentence. YEJIDE GBENGA-OGUNDARE reports that it was a bitter-sweet experience for his family who had… Read Full Story
GOVERNMENTS, religious and social organisations and the citizenry should all see COVID-19 as a common enemy and work individually and collectively to tackle its menace with a view to ensuring that it does not constitute a permanent threat to safety and the economic, spiritual and social well-being of the human society… Read Full Story
IN a video released on June 23 which went viral on the internet, Lance Corporal Martins Ndakpini of Eight Division, Nigerian Army, Sokoto, criticised the leadership of the national security and defence apparatus, including the Chief of Army Staff (COAS), Lt.-General Tukur Buratai, other service chiefs and the National Security… Read Full Story
Damilare Johnson, popularly known as Dami J, is a new act in the Nigerian music industry but his unique sound and artistic versatility are steadily making way for him in the front row… Read Full Story
It may be shocking to many seeing a decorated female Nigerian police sergeant mount a party stage as a DJ, but this is what Odiase Selimot Adejoke is generally known for. Now known as Dj Sexy Jin around entertainment circles, she recently relocated to the United States of America to join her husband… Read Full Story
You might also like
Comments

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. AcceptRead More