Weekly COVID-19 cases in America are at pre-vaccine levels, and the delta variant is infecting not only adults, but thousands of children right as the new school year begins.To get more news about
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With the sudden surge, the Centers for Disease Control and Prevention made swift changes to its mask and vaccine guidance and it continues to release new information on a daily basis. Read below for an in-depth explanation of why the rules are changing and how to best protect yourself and others from the virus.”Initially, when we were in around May or June, the situation on the ground was very different. The dominate strain, the alpha strain, was much less transmissible,” Dr. Melissa Clarke, an emergency room physician, told News4. “It appeared at the time, based on the evidence, that vaccinated people did not spread the alpha variant of the virus as much, so they were encouraged to not wear masks in an effort to make it a win-win situation.”
The delta variant changed all of that when, in late July, the CDC saw an alarming uptick in cases and hospitalizations around the country.
By that time, millions of Americans were vaccinated, but new data showed the delta variant was more infectious than other variants — even in vaccinated people. That led the CDC to recommend everyone in areas of “substantial” or “high” transmission wear a mask in public indoor places, regardless of their vaccination status.The CDC compares a virus and its variants to a tree growing and branching out. Each branch on the tree is slightly different than the others. Some branches die off, while others get stronger and spread more widely.
Scientists have studied and identified variants since the start of the pandemic. Some variants allow the virus to spread more easily or make it resistant to treatments or vaccines. Those variants must be monitored more carefully, the CDC says.
A group of scientists the World Health Organization convened recommended using the Greek alphabet, i.e., alpha, beta, gamma, delta, lambda, etc. to make it easier for people to pronounce and discuss variants of interest and concern. The alpha variant that first appeared in the United Kingdom, the beta variant that was first identified in South Africa, the gamma variant that first surfaced in Brazil and delta, which first appeared in India are classified as variants of concern.The delta variant has quickly become the dominant strain of the virus in the U.S. because of mutations that allow it to infect more people, better evade the immune system and make its hosts sicker.
“Because the delta variant has mutations on the spike protein, changes that make it more transmissible, more able to infect someone and, actually, to reproduce faster,” Clarke said.
Each virus particle is covered in spike proteins, shown in red in the illustration above, that allow it to enter and infect human cells. More than 75% of the delta variant’s spikes are primed and ready to infect. With the alpha variant, more than 50% are able to infect, researchers have found.
