Israel has again recorded another new record number of Covid-19 infections, a total of 11,365 as of midnight Thursday, as it ramps up its vaccination campaign with the third dose already given to nearly 2.5 million people to stem the fifth wave of the pandemic.
Although the country, which brought infection rates to near zero after a successful and rapid initial vaccination campaign, has seen three daily infection peaks this week, above 11,000, the infection rate stands at 8.4 per cent, down from the 10 per cent it has exceeded in previous waves.
Since the start of the pandemic, Israel has over 1.1 million cases of coronavirus and 7,120 deaths in a population of 9.3 million. In parallel to the increase in infections, the number of people vaccinated with Pfizer’s third dose has risen, with more than 5.5 people vaccinated with the full course of two injections.
That said, why are infections increasing in Israel despite high vaccination rates? There are several factors, but the most important has probably been the emergence of the much more contagious Delta variant, which has caused people who have already been vaccinated to become re-infected. There are also people who were not vaccinated or in whom it was not fully effective and, in addition, there is a decrease in protection after a period of time, especially in older people.
It should also be borne in mind that no vaccine is 100% effective. If it is 95% effective, that leaves 5% unprotected, which, if the virus is now more transmissible through the delta variant, means that more people become infected, which does not mean that if they have to be hospitalised they will end up in the ICU.
To what extent are vaccines useful?
In addition to their effectiveness against severe disease and death, another question is whether the vaccines could also be used to prevent transmission, but as they were not designed for that, it was not known at first.
With the first variants of the virus, Alpha and Beta, they worked very well to prevent transmission, but with Delta it seems that they are not working so well.
What has changed with Delta is the number of people who have to be vaccinated to achieve a very good herd immunity, which is no longer 70%, now you have to reach 90% of the population vaccinated, with this highly transmissible variant.