The double-vaccinated are almost twice as likely to be infected as unvaccinated people, data from Iceland shows. This is the same pattern as found in data from the U.K. Thorsteinn Siglaugsson has written about the trend in Morgunbladid, the main national newspaper in Iceland, and put up a translation on his website.
After December 20th, the 14-day incidence of COVID-19 infection by vaccination status took a very unexpected turn in Iceland. The infection rate per 100,000 of fully vaccinated adults with booster is now eleven times higher than on December 20th, and the infection rate of double-vaccinated adults seven times higher. At the same time, infections among unvaccinated people have grown by a factor of 2.6 only. Among children, we see a similar change: a tenfold increase among the fully vaccinated while the rate among the unvaccinated is 2.4 times higher than on December 20th.
This change can hardly be explained away by changes in behaviour, such a sudden and decisive change of behavior between groups is impossible. It is also unlikely that testing has suddenly increased this sharply among some groups and not others. We know the protection against infection from vaccination wanes rapidly, but it is out of the question that it should drop so suddenly. The most likely explanation is the new Omicron variant. Foreign data also indicate that the currently available vaccines have little or no effect against Omicron infection.
The data published on covid.is are weighted; the different size of the groups is adjusted for. This means we can use them to conclude regarding probability of infection. At present, triple-vaccinated people are only 30% less likely to get infected than unvaccinated adults, and for vaccinated children the difference is only 15%. This small difference decreases rapidly in both groups. The biggest news, however, is that double-vaccinated people are now 90% more likely to get infected than the unvaccinated. This suggests that the protection provided by two doses of vaccine is in fact less than none, it is the opposite.