From the article:
Our research at the Kirby Institute showed that, in New South Wales, using a vaccine with 90 per cent efficacy against all infection means herd immunity could be achieved if 66 per cent of the population was vaccinated.
However, using lower efficacy vaccines means more people need to be vaccinated. If the vaccine is 60 per cent effective, the proportion needing to be vaccinated rises to 100 per cent.
When you get an efficacy of less than 60 per cent, herd immunity is not achievable.
This makes perfect sense! Also, if the efficacy of the vaccine is too low it contributes to mutations.
Think of it like the ‘super bugs’ that circulate due to improper antibiotic use and over use.
The less effective vaccine = stronger mutations.
...plus...nobody knows....I had the real flu back in the 90s. Almost killed me. No one else I worked with in a secure building, nor my 2 roommates ever had it! Why?
If vaccines are the only source of immunity, perhaps.
Where does natural immunity fit into that calculation? I don’t see it.