Over the past two years, we've all become armchair experts about the virus. We know how to tell how fast it's spreading, how you get it and what you can do to protect yourself.
But it's time for people to think about another virus you don't have to worry about so much.
There's another infection you can't see, but almost certainly can feel, and perhaps even want to catch - Christmas joy.
Morning Report spoke to a couple of pandemic experts, starting with Otago University epidemiologist Professor Michael Baker.
"The reproduction number is the number of cases that each case typically infects, it's actually driven by the contact rate, the risk of transmission per contact, and how long you're infectious for," he said.
"So, if we were to apply that to Christmas joy, you can see how you could really increase your reproduction number and actually infect a vast number of people with this."
So, how do you spread it?
"First thing you'd want to do is increase your rate of contact with other people, then you have to think about the transmission per contact.
"So, how could you make your Christmas joy really stick with people? I guess that would be by being extremely enthusiastic about Christmas joy, so that people just couldn't help but absorb those feelings from you. Then the other factor is how long you're actually infected."
Baker said his 11-year-old daughter is one of the most 'infectious' - if you put her in any room and got her talking about Christmas, you're sure to be contaminated.
We also have the Christmas lights, tinsel, and potent Santa Claus variant of the virus to aid in the spread.
To map out just how far this could go, Morning Report also spoke to leading virus modeller Professor Michael Plank.
He thought we could see exponential growth just from every bit of Christmas kindness each person shows.
"One can spread some Christmas joy by doing something nice for the people around you. It doesn't have to be giving a present. That could be one step in the in the chain, with the reproduction number that eventually spreads to the whole country.
"You know, Christmas cheer can spread across international borders, the Christmas virus can really go global. Even with that reproduction number of two, it can keep spreading really quickly until it's made its way all around the world."
Plank said the increasing Christmas joy is worth keeping a close eye on.
"It would be great to see those daily case numbers of Christmas joy rocketing up, actually, seeing that spread as rapidly as possible. "
But even those who might be considered a bit of a grinch, or may have developed antibodies against Christmas Joy, should be concerned - Plank said the re-infection rate is relatively high.
"Christmas joy comes in many, many forms. Maybe it's mutating, over time if it mutates enough it could probably get around those antibodies and it could reinfect people.
"I think this is definitely the time of year when there are a lot of susceptible hosts for Christmas joy to infect."
He says Santa's data modelling elf has had a huge workload mapping out the routes the sleigh will have to take to maximise the spread, while getting around all the houses.
So, whether you've been naughty or nice, the Yuletide blessings are still up for grabs.
RNZ
