“No one gets sick on Wednesdays”

The old joke is that “no one gets sick on Wednesdays”—people get sick on a Monday or a Friday to extend the weekend, but not in the middle of the week. The only people to get sick (or, at least, pretend to get sick) on Wednesdays are doctors, who are less busy that day and call in sick to play golf.
 
“I tell the children to be sure not to get sick on Wednesdays. That’s the day our panel physician plays golf” was cited in print in 1949. “No one gets sick on Wednesdays” was in Paul Dickson’s The Official Rules and Explanations (1999).
 
 
15 April 1949, Hutchinson (KS) News-Herald, “This and that” by j. p. h., pg. 4, col. 4:
Excerpt from a letter from a friend in England which may throw a certain light on the socialized medical experiement over there: “I tell the children to be sure not to get sick on Wednesdays. That’s the day our panel physician plays golf.”
 
Google News Archive
30 July 1958, Pittsburgh (PA) Press, “Vacant Lots” by Jack Mobley (Chicago Daily News Writer), pg. 17, col. 2:
If you got sick on a Wednesday you didn’t have to go to a golf course to find a doctor.
   
Google Books
Help! I’m a Prisoner in a Chinese Bakery
By Alan King with Jack Shurman
New York, NY: Dutton
1964
Pg. 97:
NEVER GET SICK ON WEDNESDAYS
 
Google News Archive
31 January 1974, Rome (GA) News-Tribune,  “Barbs” by Phil Pastoret, pg. 11-B, col. 2:
Where does a doctor find aid if he happens to get sick on a Wednesday—unless he can locate another doctor on the golf course?
 
Google News Archive
14 May 1996, New Straits Times (Malaysia), “The joke’s on the doctor” by Dr. Eric Anderson, pg. 9, col. 4:
Alan King, a standup comic for three decades, titled a chapter of his memoirs Never Get Sick On a Wednesday, and subtitled it Unless You’re On a Golf Course.
 
Google Books
The Official Rules and Explanations:
The Original Guide to Surviving the Electronic Age with Wit, Wisdom, and Laughter

By Paul Dickson
Springfield, MA: Federal Street Press
1999
Pg. 235:
Corollary: No one gets sick on Wednesdays.
 
Google Books
Get ‘Em Laughing:
Public Speaking Humor, Quotes and Illustrations

By E. Gene Davis
Victoria, BC: Trafford
2007
Pg. 96:
No one gets sick on Wednesdays.
 
Google Books
Blonde Walks into a Bar:
The 4,000 Most Hilarious, Gut-Busting Gags, One-liners and Jokes
.
By Jonathan Swan
Berkeley, CA: Ulysses Press
2008
Pg. ?:
No one gets sick on Wednesdays.
 
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According to the Official Office Rules, no one gets sick on Wednesdays. #HappyHumpDay http://ow.ly/i/3vEEW
4:00 PM - 23 Oct 2013