“A guy walks into a bar…” is a typical form of what has been called the “bar joke.” There are various “sick joke” versions.
 
“A pile of vomit walks into a bar, the tender says ‘Is this some kind of sick joke?’” was posted on Twitter by “alex james in a very specific and limited way” on May 13, 2011. “A puddle of vomit goes into a bar. The barman says ‘What is this, some kind of sick joke?’” was posted on Twitter by Daniel Glover on October 26, 2012.
 
“The bubonic plague, the flu, and HIV walk into a bar. The bartender asks, ‘What is this? Some kind of sick joke?’” was posted on Reddit—Jokes on September 24, 2020.
 
The 2019–20 coronavirus (COVID-19) pandemic saw some “sick joke” versions. “COVID-19, the Flu, and the common cold all walk into a bar.  The bartender asks, ‘what is this?  Some kind of sick joke ...’” was posted on Facebook by Patrick Helton on September 25, 2020. “The Coronavirus, the flu, and a common cold walk into a bar.  The bartender sees them and says ‘what is this, some kind of sick joke?’” was posted on Twitter by Peter Shankman later on September 25, 2020.
     
     
Wikipedia: 2019-20 coronavirus outbreak
The 2019–20 coronavirus pandemic is an ongoing global pandemic of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The outbreak was first identified in Wuhan, Hubei, China, in December 2019, and was recognised as a pandemic by the World Health Organization (WHO) on 11 March 2020.
         
Twitter
alex james in a very specific and limited way
@SpleenShot
“A pile of vomit walks into a bar, the tender says ‘Is this some kind of sick joke?’”
10:15 AM · May 13, 2011·Twitter Web Client
   
Twitter
𝙻𝙱
@thisislucyb
A man walks into a bar and vomits. Is this some sort of sick joke?
11:43 AM · Mar 21, 2012·Twitter Web Client
   
Twitter
Daniel Glover
@GloverDaniel
A puddle of vomit goes into a bar.
The barman says ‘What is this, some kind of sick joke?”
10:25 AM · Oct 26, 2012 from Doncaster, England·Twitter for iPhone
   
Twitter
Paul Apperley
@Appz89
A puddle of vomit goes into a bar.The barman says ‘What is this, some kind of sick joke?”
10:54 AM · Oct 26, 2012·Twitter for iPhone
 
Twitter
Darren Simpson
@dakka69
A man with flu and a man with food poisoning walk into a bar.  Barman says ‘Is this some kind of sick joke?. #DadJokes
4:04 PM · Jun 7, 2015·Twitter for Android
         
Twitter
Bad Jokes Bear
@BadBritishJokes
A puddle of vomit goes into a bar.
The barman says “What is this, some kind of sick joke?” #crapjokes
1:15 AM · Mar 12, 2017·Bad British Jokes tweeter
 
Reddit—Jokes
Posted by u/Cpt_R00K13 September 24, 2020
The bubonic plague, the flu, and HIV walk into a bar.
The bartender asks, “What is this? Some kind of sick joke?”.
 
Twitter
JokesBot
@RedditJokesBot
The bubonic plague, the flu, and HIV walk into a bar. The bartender asks, “What is this? Some kind of sick joke?”.
2:09 PM · Sep 24, 2020·IFTTT
     
Facebook 
Patrick Helton
September 25, 2020 at 6:34 AM ·
COVID-19, the Flu, and the common cold all walk into a bar.  The bartender asks, “what is this?  Some kind of sick joke ...”
 
Twitter
Peter Shankman
@petershankman
The Coronavirus, the flu, and a common cold walk into a bar.
The bartender sees them and says “what is this, some kind of sick joke?”
#dadjokes
10:11 AM · Sep 25, 2020·Twitter for iPhone
   
Twitter
TSE
@TSEofPB
Coronavirus, the flu, and a common cold walk into a bar at 9:59pm.
The bartender asks “What is this? Some kind of sick joke?”
10:11 AM · Sep 25, 2020·Twitter Web App
   
Twitter
The Man Who Wasn’t There
@markg1968
Coronavirus, the flu, and a common cold walk into a bar at 9:59pm.
The bartender asks “What is this? Some kind of sick joke?”
Courtesy of
@popbitch
10:16 AM · Sep 25, 2020·Twitter Web App
     
Facebook
Dalen McVay
September 25, 2020 at 10:27 AM ·
Covid-19, the flu and common cold walk into a bar. The bartender looks at them and says “what is this some kind of sick joke?”
   
Facebook
Mark Woods
September 25, 2020 at 3:29 PM ·
Coronavirus, the flu, and a common cold walk into a bar at 9:59pm.
The bartender asks “What is this? Some kind of sick joke?”
 
Twitter
Tony C
@chefantonioUK
@LouiseLacy
Covid-19, the flu and the common cold walk into a bar.
The bartender asks, “What is this? Some kind of sick joke?”.
3:15 PM · Sep 26, 2020·TweetDeck
 
LaffGaff
Disease Bar
September 27, 2020 by laffgaff
The bubonic plague, the flu, and HIV walk into a bar.
The bartender asks, “What is this? Some kind of sick joke?”