Herd immunity is the indirect protection against infectious disease that populations acquire when humans are sufficiently immune. The threshold required to achieve it depends on many different factors, such as the number of reproductions of the virus, or “R” – the number of others on each carrier – which is itself widely changing. Some of the factors that influence the latter include where in the world you live, the variability involved, and the conditions on the ground, such as locks. -lock.
This means that even when scientists know more, there will not be a set threshold for the immunity of a herdsman to work everywhere – but it is possible to estimate around what might be to be there.
For example, one calculation suggests that, for a vaccine that completely eliminates transmission, 60-72% of the population would need to have it, in order to achieve total herd immunity. But if the vaccine was 80% effective, it must have between 75 and 90% of people.
This may be higher than the vaccine intentions of many countries. The UK aims to give all adults vaccinated by September, which equates to around 51m out of 67.5m people – 75% of the total population. That assumes that every adult in the country is willing to be vaccinated, and healthy enough to deserve it.
However, most scientists do not intend to eradicate the virus completely. For now, the goal is to reduce the spread as much as possible. “Even if you are vaccinated, you may still have a relatively high number of people there,” said Chief Executive. “So we still see events happening. I think they would be relatively local, but they would still cause concern and cause a burden of disease “.
Some scientists argue that red herring is the key to preventing transmission, because once enough people have been vaccinated, it doesn’t matter if they can still spread the virus – everyone will have immunity.
However, it may be vital for those who are unable to get the vaccine, for example because they are pregnant, too young, or too ill.
Until we have an answer, maybe we should all remember the story of the 11 – year – old boy with mumps – and act like we didn’t get the vaccine, even if we did.
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