WHAT SPREADS FASTER THAN COVID-19? VACCINATION.

It deserves a wow. Some 57% of the human population has received at least one dose of the Covid-19 vaccine, and 45% are fully vaccinated, in less than a year.

This means the vaccine has spread approximately twice as fast as the virus, never mind that the virus itself is an exceptionally fast spreader that organizes its own distribution without help from trained administrators and sub-zero storage.

Add that infection also offers a kind of vaccination, so now two kinds of resistance to Covid-19 have been spreading with unprecedented rapidity through the human population.

Numerous were the complaints about how Delta spoiled the summer even for vaccinated people, but it’s not clear why this was so. Vaccination takes away Covid’s deadliest property, its novelty to the human immune system, turning it into the equivalent of a cold or flu. Nobody lets the prospect of a cold or flu spoil their holiday (though perhaps they should for the sake of their elderly in-laws).

The point is not frivolous. It suggests why, rather than a dark new chapter, the Omicron variant may be our last big wallow in hysteria, from which we will awake slightly red-faced in the morning.

Start with numbers and remind yourself that what turned Covid into a global catastrophe wasn’t its unusual deadliness—in unvaccinated people, it appears to be roughly twice as deadly as the flu when unvaccinated apples are compared to unvaccinated apples; in vaccinated people it appears to be significantly less deadly given that our standard flu mortality estimate of 0.1% arises in a U.S. population in which vaccination approaches 70% for the riskiest age brackets.

The big disturber of our equanimity was Covid’s rapid spread—with so many of us getting our high-risk first exposure in a compressed period of time, straining the world’s hospitals.

With flu, the U.S. government estimates that 5% to 20% of us (with or without symptoms) are infected each year; about half of us are vaccinated. With Covid, a government-sponsored study recently estimated that 100 million were infected in 2020, or 30% of the U.S. population, at a time when almost nobody was vaccinated.

This speed of transmission is what keeps throwing the world for a loop; moreover, it seems indisputable in retrospect that we squandered our best point of leverage by failing to focus on protecting the elderly and those at highest risk.

Well, some people proposed that, you know. Others, like Andrew Cuomo, put Covid patients into nursing homes.

Related: The Lancet:

High COVID-19 vaccination rates were expected to reduce transmission of SARS-CoV-2 in populations by reducing the number of possible sources for transmission and thereby to reduce the burden of COVID-19 disease. Recent data, however, indicate that the epidemiological relevance of COVID-19 vaccinated individuals is increasing. In the UK it was described that secondary attack rates among household contacts exposed to fully vaccinated index cases was similar to household contacts exposed to unvaccinated index cases (25% for vaccinated vs 23% for unvaccinated). 12 of 31 infections in fully vaccinated household contacts (39%) arose from fully vaccinated epidemiologically linked index cases. Peak viral load did not differ by vaccination status or variant type [[1]].

In Germany, the rate of symptomatic COVID-19 cases among the fully vaccinated (“breakthrough infections”) is reported weekly since 21. July 2021 and was 16.9% at that time among patients of 60 years and older [[2]]. This proportion is increasing week by week and was 58.9% on 27. October 2021 (Figure 1) providing clear evidence of the increasing relevance of the fully vaccinated as a possible source of transmission. A similar situation was described for the UK. Between week 39 and 42, a total of 100.160 COVID-19 cases were reported among citizens of 60 years or older. 89.821 occurred among the fully vaccinated (89.7%), 3.395 among the unvaccinated (3.4%) [[3]]. One week before, the COVID-19 case rate per 100.000 was higher among the subgroup of the vaccinated compared to the subgroup of the unvaccinated in all age groups of 30 years or more. In Israel a nosocomial outbreak was reported involving 16 healthcare workers, 23 exposed patients and two family members. The source was a fully vaccinated COVID-19 patient. The vaccination rate was 96.2% among all exposed individuals (151 healthcare workers and 97 patients). Fourteen fully vaccinated patients became severely ill or died, the two unvaccinated patients developed mild disease [[4]]. The US Centres for Disease Control and Prevention (CDC) identifies four of the top five counties with the highest percentage of fully vaccinated population (99.9–84.3%) as “high” transmission counties [[5]]. Many decisionmakers assume that the vaccinated can be excluded as a source of transmission. It appears to be grossly negligent to ignore the vaccinated population as a possible and relevant source of transmission when deciding about public health control measures.

The vaccinations seem to be underperforming. It may be that we should have focused vaccination on the elderly and infirm too.