Historical clue formulations

• Reason to take a shot — 2026-08-16
• Target of an annual vaccine — 2026-08-09
• It goes around every year — 2025-10-20
• Seasonal malady — 2025-07-17
• Seasonal threat — 2024-07-20
• Target of a seasonal shot — 2024-07-14
• Seasonal vaccine target — 2024-06-05
• Bug that sounds like it was in the air? — 2024-02-17
• Apt rhyme of "Achoo!" — 2023-09-24
• Winter bug — 2023-07-16
• ___ season — 2023-06-24
• Target of an annual shot — 2022-11-13
• Common bug — 2022-08-12
• Bug that no one likes — 2022-04-14
• ___ vaccine — 2021-11-02
• ___ season — 2021-02-25
• Winter malady — 2020-10-28
• Reason for seasonal shots — 2020-03-11
• Ailment with a "season" — 2020-02-09
• ___ shot — 2019-10-24
• Vaccine target — 2019-07-30
• Bug mostly seen in winter — 2019-02-04
• Kind of shot — 2018-01-28
• Seasonal woe — 2017-07-27
• Bug that thrives in the winter — 2016-12-07
• Focus of a yearly shot — 2016-11-21
• Certain bug — 2016-10-27
• It might give you the chills — 2016-09-05
• Annual vaccine target — 2016-08-03
• Word before shot or season — 2016-04-26
• ___ bug — 2015-09-20
• Winter woe — 2015-09-03
• Annual winter outbreak — 2015-05-18
• Kind of season — 2015-04-26
• ___ season — 2015-03-29
• ___ shot — 2014-08-07
• Winter woe — 2013-11-26
• Something you might get shot for? — 2013-10-13
• Bird ___ — 2012-10-28
• Swine ___ — 2012-04-25
• It might make you go "Achoo!" — 2011-09-26
• Kind of shot — 2011-07-17
• Grippe — 2011-05-24
• Winter malady — 2011-04-25
• W.H.O. concern — 2010-12-03
• Yuppie ___ (chronic fatigue syndrome) — 2008-12-17
• Possible work force reducer — 2008-02-15
• Kind of season — 2007-06-29
• Bird ___ — 2006-08-06
• Bird ___ — 2006-02-17