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The Covid-19 Delta variant originally discovered in India is now spreading around the world and becoming the dominant strain in some countries like the UK and likely to become so in others like the US

On Wednesday, the World Health Organization announced that the variant has been detected in more than 80 countries and continues to mutate as it spreads.

The variant now accounts for 10% of all new cases in the US, up from 6% last week. Studies have shown that the variant is even more transferable than other variants.

Scientists have warned that the data suggest the Delta variant is 60% more transmissible than the “Alpha” variant (formerly known as the UK or Kent variant, which itself was much more transmissible than the original version of the virus) and more likely to result in hospital admissions, as has been observed in places like the UK

WHO officials said Wednesday there are reports that the Delta variant also causes more severe symptoms, but that more research is needed to confirm these conclusions.

Still, there are indications that the Delta variant could produce different symptoms than the ones we should look out for with Covid-19.

What do you have to pay attention to?

Throughout the pandemic, governments around the world have warned that the main symptoms of Covid-19 are fever, persistent cough, and loss of taste or smell with some domestic variations and supplements as we learned more about the virus.

The updated list of CDC symptoms includes, for example, fatigue, muscle or body aches, headache, sore throat, constipation or runny nose, nausea or vomiting, and diarrhea as possible symptoms of infection. There are of course the millions of people who have had Covid-19 without symptoms, with the extent of asymptomatic transmission still being studied by scientists.

But the delta variant appears to provoke a different set of symptoms, according to experts.

Tim Spector, Professor of Genetic Epidemiology at King’s College London, leads the Zoe Covid Symptom study, an ongoing study in the UK that allows the public to enter their Covid symptoms into an app when scientists can then analyze the data.

“Covid is behaving differently now,” Spector stated in a YouTube briefing last week. “It’s more like having a bad cold in this younger population and people don’t realize it and that hasn’t come up in any of the government reports.”

“We’ve been looking at the top symptoms among app users since early May and they’re not the same anymore,” he said. “Symptom number one is a headache, followed by a sore throat, runny nose and fever.” “More traditional” Covid symptoms like coughing and loss of smell are now much less common, he said, and younger people are much more likely to have a bad cold or a “strange feeling”.

First discovered in the UK, the alpha variant illustrated the appearance of a wider range of symptoms.

A study of over a million people in England as part of the REACT study (which tracks community transmission of the virus in England), which was carried out between June 2020 and January 2021 – over a period in which the alpha – Variant spread and became dominant – showed additional symptoms associated with the coronavirus, including chills, loss of appetite, headaches and muscle aches, in addition to the “classic” symptoms.

Worrying variant

This week, the Centers for Disease Control and Prevention rated the Delta variant as a “variant of concern” based on increasing evidence that the Delta variant spreads more easily and compared to other variants, including B. 1.1.7 (Alpha), “it said in a statement to NBC News.

Dr. Scott Gottlieb, a former commissioner for the Food and Drug Administration, said the Delta variety is likely to become the dominant strain in the US and “could spark a new epidemic in the fall,” during an interview with CBS “Face the Nation” Sunday .

In the UK, where the Delta variant is now responsible for the majority of new infections, cases have increased in young people and unvaccinated people, leading to an increase in hospital admissions in these cohorts. The spread of the variant has also caused Great Britain to postpone the further relaxation of the Covid-19 restrictions.

There is hope that Covid-19 vaccination programs can stop the wild spread of the Delta variant, so the race is to protect younger people who may not be fully vaccinated. An analysis published by Public Health England on Monday showed that two doses of the Pfizer BioNTech or Oxford AstraZeneca Covid-19 vaccines are highly effective against hospitalizations from the Delta variant.

The situation in Great Britain shows how quickly the delta variant can establish itself and the USA is certainly watching this with concern.

Dr. Anthony Fauci, chief medical adviser to the president, noted last week that “we cannot allow this to happen in the United States” when he urged more people to be vaccinated, especially young adults.

The latest study on the spread of the virus in England alone cannot allay experts’ concerns. The latest REACT study results, released Thursday, warned that cases were increasing “exponentially” and said the “resurgence” of Covid-19 infections in England was “with an increased frequency of the Delta variant connected”.

The study estimates that about 1 in 670 people have the virus, a sharp increase compared to previous study’s results when 1 in 1,000 people had the virus on May 3. The results were released Thursday and are based on nearly 110,000 home swab tests performed between May 20 and June 7.

Led by Imperial College London, the scientists estimate that the number of reproductions in England is now 1.44, meaning that 10 infected people would, on average, pass the virus on to 14 others, “leading to rapid growth of the epidemic”.

Professor Paul Elliott, Director of the REACT Program at the Imperial School of Public Health, said, “We found strong evidence of exponential growth in infection from late May to early June … These data are consistent with the dominance of the Delta variant and show how It is important to continue infection and monitor infection rates and worrying variants in the community. “

Most infections occur in children and young adults, but they are also increasing in the elderly, the study found.

While the link between infections, hospital admissions and deaths had weakened since February, suggesting that infections resulted in fewer hospital admissions and deaths due to the vaccination program, the trend reversed for hospital admissions since late April.

– CNBC’s Rich Mendez contributed to coverage of this story.