Yesterday, Castilla – La Mancha announced that it will begin the vaccination of the 30-39 year old age group in just 10 days; Galicia decided to open it to everyone over 18 years of age in July, something that (with some peculiarities) the Canary Islands had also launched. The vaccination campaign is about to face its third objective and, with it, one of the most critical parts of the exit from the pandemic.
Because, as epidemiological data improve and the number of vaccinated increases, the risk of the situation getting out of control increases. The best example of this is perhaps the city of Antequera which, in 15 days and coinciding with school graduations and the “return to normality” in nightlife, has gone from having a cumulative incidence to 14 days of 87 cases to 588. This is a growth of 319%.
Vaccination has changed the physiognomy of virus waves, but (and this is important to remember) complete and widespread vaccination. Just this week, an Israeli study just confirmed that, in the real world, the first dose of Pfizer’s vaccine it is 54.4% effective against symptomatic infection (and 51% against infection confirmed by PCR). Of course, between 13 and 24 days after the injection.
LESS than 100 DAYS for GROUP IMMUNITY: Towards a FUTURE without PANDEMIC
Correctly understand the effectiveness of the vaccine
The data is mind-boggling, certainly. Let’s remember that, in general terms, those were the data from the clinical trial. That is, the results of the vaccine in real conditions (and, necessarily, full of unforeseen events and errors) are very similar to when they tested it in healthy participants and with optimal and monitored storage and distribution conditions. This was one of the great unknowns that remained pending and this analysis of more than half a million people sheds light on the matter.
However, the most interesting thing is to remember what this really means. Obviously, an effectiveness of 54.4% does not mean that half of those vaccinated will contract the coronavirus. What it means is that a person (between 13 and 24 days after the first dose) has 50% less risk of infection than an unvaccinated person. This is a lot, yes; worse also very little.
The immunity acquired with vaccines makes it difficult for the virus to move as fast as before, but in population terms those figures are still too low to give us some security. We have seen how other countries, despite being vaccinated at a good rate, saw their epidemiological situation deteriorate rapidly. We are safe from repeating the tragic problems of a year ago, but the pandemic is still very much alive.