The current state of information regarding the COVID pandemic, vaccine efficacy, Delta variant, mask mandates, etc., is nothing if not confused. Reports of "surges," breakthrough infections, booster shots and so forth leave the answers to such basic questions as "do vaccines work?" and "does mask wearing do anything?" uncertain. There appears to be either no source of reliable information regarding these questions, or such sources are few and hard to come-by.
First, there is no COVID information that should not be scrutinized for ulterior motives, insular agendas, and shaky foundation. The course of the pandemic has seen news media awash with anecdotes, dubious associations, unfounded claims, contradictory recommendations, inaccurate modeling and "unexpected" events. It is certainly possible that information regarding COVID is slanted to encourage compliance with "best-we-can-do" but still not very good interventions. It is also at least possible that political motives, such as interest of teachers unions in delaying return to in-person teaching affect the content and presentation of COVID information. Controversial topics such as vaccine passports, and the "right" of strangers to know an individuals vaccination status may be surrogates for other political or even cultural interests. What seems certain is that the simplistic models that are used to support things like six-foot social distancing, double masking, and lockdowns do not appear to be validated by actual experience.
There are several items of information that add confusion to the state of popular COVID knowledge, but which nonetheless may be used to understand the current state of the COVID pandemic and efforts to control it. Among these are reports of a significant number of "breakthrough" infections in vaccinated people, and exponential increases in the number of cases in places with relatively high vaccination rates such as the United Kingdom, Israel and the Seychelles. Other observations, such as a divergence in the case numbers and mortality rates, marked regional variation in case numbers that seem to be independent of vaccination rates, and the rapid rise and fall of infection numbers in India suggest that we are relying on incomplete understanding of the virus, immunological response and the influence of environmental factors. There are also intriguing observations regarding the quantification of virus found in vaccinated and unvaccinated people that may explain much of the confusing experience.
With specific regard to vaccinations, the rise in breakthrough cases and surges in relatively highly vaccinated populations suggests several possibilities. If we consider the state of vaccine information over the past year, we observe that vaccines were reported to have >90% efficacy in preventing COVID, that these vaccines were perhaps associated with blood clots, myocarditis, and hearing loss, that they were at least somewhat efficacious against the Delta variant, that boosters would be needed, etc. Much of these data seem to be unconfirmed extrapolations from limited observations, perhaps mixed in with wishful thinking and pubic relations spin. Again, the key to understanding this and resolving some of the apparent contradictions in this information is the observation that viral counts in vaccinated and unvaccinated people appear to be similar.
There are some straightforward but perhaps overly simplistic explanations for the COVID experience to date. One is that the vaccines do not work, which is likely at least somewhat true for the Russian and Chinese vaccines; that they work but the protection against infection decays exponentially, with a half-life of about 4 to 8 months (thus the need for "boosters;" or perhaps that the rational approach taken to develop COVID vaccines was based on an incomplete understanding of immunity against COVID.
We may take as true the following: vaccines are intended to stimulate the immune system to produce antibodies against the coronavirus spike protein; the vaccines do in fact produce measurable antibody responses; these antibodies are not reliable in protecting against subsequent infection and viral replication, even if they mitigate the severity of a particular infection and perhaps reduce morbidity and mortality. Here is a hypothesis that may explain these phenomena: the important immunological response to COVID is not the production of antibodies directed against the spike protein. These antibodies may decrease the effective inoculation viral dose, but do not stimulate an immune response that prevents or hinders viral replication. This is why viral counts in vaccinated and unvaccinated people are similar, and if the hypothesis is true, explains why vaccinated people can infect others.
Our understanding of the immune response is that antigens are taken up by immune cells, which then present antigens that direct the immune system to stimulate a protective, and likely complicated response that combats the infection. It may be the case that the spike protein is not the most efficient, or competent antigen to stimulate an effective response. It may be reasonable to target the spike protein because that supposedly provides specificity with regard to the pathogen, but the assumption that one antigen is the same as another in terms of immune response is possibly fallacious. Therefore when we use a surrogate for vaccine effectiveness, such as antibody count, we miss what we are actually interested in: effectiveness at preventing the spread of infection.
Since coronaviruses describe a large class of pathogens, it is possible that the human immune system is more efficient if it does develop lasting immunity to every coronavirus encountered during the course of a lifetime. In other words, there may be a sound evolutionary basis for why the immune response to coronaviruses is not durable. Whatever the case, breakthrough infections, "surges" in vaccinated populations and considerations of booster shots all suggest that vaccination does not provide durable immunity against COVID. This does not mean that vaccination is futile, or does not provide a benefit. It rather suggests that expectations for vaccine efficacy should be prudently tempered, and that widespread vaccination even if effective eventually hits a point of diminishing returns.
The upshot of all of this is that the apparently confused state of COVID Information likely has many causes, from spun and slanted reporting, to inappropriate extrapolations from limited data, to incompletely understood pathophysiology of disease and immune response.
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