COVID-19: TikTok comedian claims complicated math skills used to predict NSW caseload - but he could simply be subtracting numbers

A TikTok comedian on Sunday correctly revealed the number of new COVID-19 cases in New South Wales for the fifth day in a row.

And the social media star claimed on Sunday night he uses the "Kairouz probability algorithm" to decipher the information - but it could be much more simple than that.

Jon-Bernard Kairouz went viral this week when he began claiming he was using mathematical equations to predict the number of COVID-19 cases that would be later announced by NSW Premier Gladys Berejiklian.

He correctly predicted Sunday's 105 new infections on Saturday night - and believes 109 cases will be reported on Monday.

Kairouz spoke to The Project Australia on Sunday night, saying the "complex calculus" he uses allowed him to correctly predict five in a row.

"We also take into account the infectious community cases and then we can deduce a concrete figure we are happy to push out to the public."

But the Daily Mail speculates he could be using the government's Coronavirus Australia app, which updates infection numbers state-by-state, to decipher the figures.

NSW reports its case numbers to 8pm the previous day. The Daily Mail says the Coronavirus Australia data is updated at that same time - but isn't publicly reported until Berejiklian holds her daily press conference at 11am (local time). 

If the theory the Mail reports is accurate, all that's required to decipher the case numbers is to subtract the most recent day's case numbers from the previous. Based on this, there would be 109 cases reported on Monday - the same number Kairouz predicted.

There have been other theories that Kairouz is obtaining the numbers from a source within NSW's health department - something he's denied.

Berejiklian was asked on Friday if she was concerned someone was leaking the numbers to Kairouz.

"All we can do is focus on the job at hand," she answered. 

"I know at the moment a lot of people have, or [are] alleged to have, various bits of information and advice but what is important for us as a team - team New South Wales - is to focus on what is necessary and that is to lead our state during the most challenging of times."