How can mRNA vaccines defeat this virus? Current mRNA vaccines result in translation of only part of the motif for the S spike protein of the virus, one of many proteins that make up the virus. Meanwhile the virus is mutating within hours to adapt to the antibody a healthy immune system produces in response to the partial S protein motif. But also meanwhile the virus is mutating rapidly to adapt to other motifs and immune bodies attacking it. Likely the antibody created will have recognition for S protein motif adjacent or similar to the designed motif. But what then? The virus continues to mutate and adapt to survive and replicate. But the mRNA-designed motif is static and non adaptive.
The same logic applies to virus from less developed countries. Healthy immune systems there are more challenging for the virus compared to most immune systems in more pristine environments. Virus which escapes after surviving in these developing countries is much more dangerous to immune systems in pristine environments.
Meanwhile today’s mRNA vaccines are static, fitting a motif for a virus population whose original sequence and motif will soon disappear or be out-competed and replaced by stronger virus. mRNA vaccines may make sense when they become adaptive to mutations.
I should add that an mRNA vaccine which had the capability to adapt to various and increasing viral mutants likely would be problematic for the host because viruses survive and replicate by sharing chemistries such as enzymes and cellular processes with host cells after penetration/infection. So, if a adaptive vaccine could be made it could easily cause autoimmunity and bigger problems than the virus itself.