Fogbow

RTH10260 wrote: ↑Thu Apr 07, 2022 4:37 pm "We don't need no Dr Fauci to know all this, we have herd immunity!"

... And the case wave will be bigger than it looks, they say, because reported numbers are vast undercounts as more people test at home without reporting their infections or skip testing altogether.

The majority of cases in the U.S. — around 75 percent — are still caused by BA.2., which has been the country's dominant variant since late March.

But BA.2.12.1, along with another version of omicron, called BA.2.12, is said to be responsible for the recent spike in Covid cases seen in upstate New York, the State Department of Health said last week.

State health officials estimated the latest variant to be 23 to 27 percent more transmissible than BA.2, which itself was more transmissible than the original omicron variant. However, there's currently no evidence to suggest that BA.2.12.1 causes more severe disease.

Federal and state officials have been watching the New York outbreak closely to see if it leads to an increase in Covid hospitalizations, which tend to lag cases by several weeks.

A Guide to the Different Omicron Subvariants
How to tell the different versions of SARS-CoV-2 apart, and how well vaccines protect against them

By Louis Jacobson, Kaiser Health News on May 6, 2022

Two years into the coronavirus pandemic, Americans can be forgiven if they’ve lost track of the latest variants circulating nationally and around the world. We’ve heard of the alpha, beta, gamma, delta, and omicron variants, but a new Greek-letter variant hasn’t come onto the scene in almost half a year.

Instead, a seemingly endless stream of “subvariants” of omicron, the most recent Greek-letter variant, has emerged in the past few months.

How different are these subvariants from one another? Can infection by one subvariant protect someone from infection by another subvariant? And how well are the existing coronavirus vaccines—which were developed before omicron’s emergence—doing against the subvariants?

We asked medical and epidemiological experts these and other questions. Here’s a rundown.

Q: What are the subvariants? How much do they differ from one another?

The omicron subvariants seem like an alphabet soup of letters and numbers. The original omicron variant was called B.1.1.529. The initial omicron variant begat such subvariants as BA.1; BA.1.1; BA.2; BA.2.12.1; BA.3; and the most recent, BA.4 and BA.5.

“They all differ from each other by having different mutations in the spike protein,” which is the part of the virus that penetrates host cells and causes infection, said Dr. Monica Gandhi, a professor of medicine at the University of California-San Francisco.

The minor-to-modest mutations in these subvariants can make them marginally more transmissible from person to person. Generally, the higher the number following “BA” in the subvariant’s name, the more transmissible that subvariant is. For instance, BA.2 is thought to be about 30% to 60% more transmissible than previous subvariants.

These mutations have enabled subvariants to spread widely, only to be overtaken by a slightly more transmissible subvariant within a few weeks. Then the process repeats.




https://www.scientificamerican.com/arti ... bvariants/

WaPo newsletter wrote:The newest omicron offshoot, BA.5, is sweeping across the United States. But spotty testing and data collection has significantly hampered the nation’s ability to accurately track the number of new cases. Some epidemiologists think there could be as many as 1 million new cases a day, and one expert called BA.5 “the worst version of the virus that we’ve seen.” The latest subvariant is taking over quickly because it can easily dodge immunity from prior infections and vaccines, increasing the risk of reinfection.

How multiple COVID-19 infections can harm the body

Reinfection rates are rising with the emergence of the more infectious Omicron variant, with some people even reporting their third or fourth infection. Now, scientists are warning that each bout increases your risk of troubling outcomes, from long COVID to heart disease.

Findings of a pre-print study published in June suggest that people who get sick multiple times may have a higher risk of long-COVID symptoms.

Dr. Ziyad Al-Aly, a clinical epidemiologist at Washington University in St. Louis, looked at thousands of cases of reinfection and saw a wide range of problems in the months that followed: certain respiratory conditions, cough, shortness of breath, fatigue, brain fog and other conditions including metabolic disease, cardiac disease, kidney disease and diabetes.

"Altogether, we concluded that reinfection contributes to additional risk," Al-Aly says. "So even if you're vaccinated ... it's absolutely best to avoid reinfection."

And a study published last week in the journal Cell concludes that repeat infections are likely. Researchers studied blood samples from people who had been vaccinated and boosted, and they found they had a reduced ability to neutralize the BA.5 virus, compared to prior sub-variants, BA.1 and BA.2.