Omicron variants: BA.2 may cause more severe disease?

Omega Variant: Could BA.

Could an upgraded omicron cause more severe disease? New research sounds the alarm

At present, European and American countries have gradually introduced epidemic prevention measures

But a new Japanese study found that a new subvariant, BA.

Japanese researchers published a research report on the preprinted version of "bioRxiv" on the 15th, saying that BA.

 This result has caught everyone's attention: since February this year, the number of BA.

BA.

 Previously, the academic community agreed that BA.

 Japanese researchers conducted hamster infection experiments for comparison

The researchers found that the RNA load of BA.

In contrast, ba .

BA.

 This suggests that BA.

Post-infection 'herd immunity' may not be as effective

The number of people with acquired immunity after infection is relatively large, which is one of the advantages of European and American countries

As the predominant strain globally, BA.

BA.
1 convalescent serum showed strong antiviral effect on BA.
1 strain, but the effect on BA.
2 seemed to be poor, and its resistance to serum was 1.
4 times that of BA.
1 strain
.
The researchers repeated the experiment in mice and came to similar conclusions:

Compared with BA.
1, the resistance of BA.
2 to hamster serum was significantly increased by about 2.
9 times during the recovery period of BA.
1 infection
.

 The researchers also used the S protein of BA.
1 to immunize mice to obtain antiserum, and used the mouse serum neutralization test.
The results showed that the resistance of BA.
2 to immune serum was 6.
4 times that of BA.
1
.

Not to mention those who were infected early in the pandemic
.

Studies have shown that BA.
2, like BA.
1, is highly resistant to convalescent serum, whether it is the original strain Alpha or Delta
.

A simple understanding is that it may not be as "safe" to face BA.
2 as you might think, regardless of whether you have infected other mutants early or recently with BA.
1
.

Do vaccines still work? What about antiviral drugs? In this regard, BA.
2 continues the capabilities of BA.
1 and seems to be slightly better
.

Pseudovirus and vaccine-induced neutralizing antibody experiments showed that BA.
2 was highly resistant to both mRNA and adenovirus vaccines
.
In addition, BA.
2 was almost completely resistant to two therapeutic monoclonal antibodies, Casirivimab and Imdevimab
.

British scholars question the government: relaxation of epidemic prevention should provide scientific basis

However, the mouse experiments cannot fully reflect the actual situation, and there are certain differences in the pathology and infection kinetics of the virus between humans and experimental animals
.

Back in the real world, the evidence on the severity of BA.
2 is mixed
.
In countries where outbreaks have been contained, such as South Africa and the United Kingdom, hospitalizations continue to decline
.
But in Denmark, where BA.
2 has become a major source of infection, hospitalizations and deaths are rising
.

This study is more of a wake-up call for us
.
Deborah Fuller, a virologist at the University of Washington School of Medicine, believes that creating a system to specifically test for BA.
2 will be the first thing many countries need to do
.

Distinguishing BA.
1 from BA.
2 requires whole-genome sequencing, which is a relatively time-consuming and laborious process
.
In a country where cases are growing in the tens of thousands, it is not easy to obtain relevant data and analyze it in a timely manner
.

"Has the performance of humans surpassed the virus now?" Until the relevant data comes out, I don't think the epidemic prevention regulations can be lifted
.
"

Penelope Tove, chairman of the British Medical Association's Public Health Medicine Branch, said recently that the number of confirmed cases in the UK is still high, with hundreds of people dying every day, but the UK has lifted epidemic prevention measures such as self-isolation
.
"We have the right to question whether the government's decision is based on science
.
"

Lawrence Young, a virologist at the University of Warwick, believes the pandemic is not over
.

"If there's one thing we've learned over the past two years, it's that the impact and future of Covid-19 remains unpredictable," said Lawrence Young
.

(Source: Internet, reference only)

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