Related Clues:

• Concern of a global WHO program
• Midsummer Day month
• Bug that's not hard to catch
• When summer officially starts
• Common cause for sick days
• Word before shot or season
• Source of unwelcome strains
• Month of our summer solstice
• Most popular month for American weddings
• Annual vaccine target
• It's "bustin' out all over"
• It might give you the chills
• Winter weakener
• Minor ailment
• Seasonal ailment