Many of us are wondering when this COVID-19 pandemic will end? Yes, when will it end!
Tegan Taylor addresses this question in her article How do pandemics usually end? And how will this one finish?
According to virologist Kirsty Short from the University of Queensland "There's not going to come a day where we say, 'OK, on [this date], this will no longer be a problem'. It's going to be a continuum".
Dr Short says an infectious agent needs three conditions to cause a pandemic:
- It needs to cause disease in humans
- It needs to be highly transmissible
- We need to have no pre-existing immunity to it
The big thing that stops a virus becoming a large-scale outbreak is the third factor: immunity.
"Herd immunity can be achieved through natural infection or vaccination" continued Dr Short. Social distancing and masks help prevent the virus from spreading as much.
The 2009 swine flu spread at a pandemic rate. But a sufficient amount of the population had immunity to it, because they'd had the vaccine or had immunity to it because they had had the virus.
This meant that if they got infected then they were less likely to transmit it and it was less likely to be severe.
But the virus didn't go away. It was still there in 2010. Fortunately there was enough pre-existing immunity to the 2009 strain so it didn’t become a pandemic says Dr Short.