YOU MAY have heard the term 'herd immunity' banded about from time to time over the past year or so, particularly during discussions about Covid-19 and how to beat the b*stard once and for all.
Achieving herd immunity is considered, by many, to be the most effective and fastest route to end of the pandemic.
There are a number of ways to achieve it, and as such, people are divided - in Ireland, and indeed around the world - when it comes to what might be the best strategy.
So just in case you're a little unsure, here's a quick summary:
What is herd immunity?
Herd immunity - also known as 'population immunity' and 'community immunity' - is when a population becomes protected from an infectious disease because the majority of that population is immune.
This immunity can be achieved in two ways:
- Vaccination against the disease
- Exposure to - and recovery from - the disease
Anyone who has been vaccinated against or recovered from a disease will produce anti-bodies that will protect them from getting infected again.
Once the majority of people have this resistance, the disease will be theoretically unable to spread easily from person to person, and should soon disappear.
What percentage of the population needs to be immune?
There's no absolute rule when it comes to herd immunity. The percentage of the population that must be immune will depend on the disease, and also on political and geographical variables like population size, border control etc.
Initially, scientists said that around 60-70% of any given population will need to be immune against Covid-19 before herd immunity can be achieved. But this estimate has since been revised, with some claiming the threshold might be as high as 85%.
Given that Covid-19 is a new disease, and given the number of mutated variants spreading around, no one can really be certain. But what is certain is that the more people develop resistance, the closer that population will be to herd immunity.
When will herd immunity be achieved in Ireland?
Ireland is in the midst of a mass-rollout of Covid-19 vaccines. The Government has previously said that it aims to have 80% of the population vaccinated by mid-September, but this could change if there are any further vaccine production issues.
If this does indeed happen, then Ireland can expect to have achieved herd immunity any time between the end of summer of the start of autumn.
