A WSJ piece notes:
Public-health experts are sounding the alarm about a new Omicron variant dubbed XBB that is rapidly spreading across the Northeast U.S. Some studies suggest it is as different from the original Covid strain from Wuhan as the 2003 SARS virus. Should Americans be worried? It isn’t clear that XBB is any more lethal than other variants, but its mutations enable it to evade antibodies from prior infection and vaccines as well as existing monoclonal antibody treatments. Growing evidence also suggests that repeated vaccinations may make people more susceptible to XBB and could be fueling the virus’s rapid evolution.
The Nature article states:
Continuous evolution of Omicron has led to a rapid and simultaneous emergence of numerous variants that display growth advantages over BA.5 . Despite their divergent evolutionary courses, mutations on their receptor-binding domain (RBD) converge on several hotspots. The driving force and destination of such sudden convergent evolution and its impact on humoral immunity remain unclear. Here, we demonstrate that these convergent mutations can cause striking evasion of neutralizing antibody (NAb) drugs and convalescent plasma, including those from BA.5 breakthrough infection, while maintaining sufficient ACE2 binding capability. BQ.1.1.10 (BQ.1.1+Y144del), BA.4.6.3, XBB, and CH.1.1 are the most antibody-evasive strains tested. To delineate the origin of the convergent evolution, we determined the escape mutation profiles and neutralization activity of monoclonal antibodies (mAbs) isolated from BA.2 and BA.5 breakthrough-infection convalescents .
Due to humoral immune imprinting, BA.2 and especially BA.5 breakthrough infection reduced the diversity of the NAb binding sites and increased proportions of non-neutralizing antibody clones, which in turn focused humoral immune pressure and promoted convergent evolution in the RBD.
Moreover, we showed that the convergent RBD mutations could be accurately inferred by deep mutational scanning (DMS) profiles , and the evolution trends of BA.2.75/BA.5 subvariants could be well-foreseen through constructed convergent pseudovirus mutants.
These results suggest current herd immunity and BA.5 vaccine boosters may not efficiently prevent the infection of Omicron convergent variants.
Now let us see if we can unfold this issue:
1. The WSJ is stating things without, in my opinion, any adequate basis in fact.
2. The article is based on China only studies
3. The article has not been released
4. The China vaccines are NOT the US/European mRNA vaccines are are well know to be much less effective
5. Low efficacy allows mutations
6. China is now a source of major mutations because of their ineffective vaccines.
7. This SS RNA virus is subject to many mutations depending on how long it takes the infected person to respond.
8. To protect US and European citizens an immediate quarantine should have been adopted. Alas we have the same crew as three years ago so do not expect anything better!
9. New vaccines can be developed rapidly and should be. That means at least annual if not semi annual immune efforts.
10. The only way to fight this off is to have an aggressive near real time vaccine effort.
11. Vaccine neither prevent the disease nor do they inhibit transfer. They do mitigate responses. In addition the antivirals can effect improvement in those with poor vaccine responses or otherwise compromised.
BUT, it is the Government that must take steps forward and do not expect any response.
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