The disease linked to Valentine’s Day by name is syphilis. It is often nicknamed “the Valentine disease.”

Reason: According to historical accounts, Saint Valentine was said to have suffered from (and possibly died of) syphilis, so the infection became symbolically tied to him and to romantic love.

Medical facts: Syphilis is a sexually transmitted infection caused by Treponema pallidum.
 
It spreads mainly through sexual contact and can pass from mother to child during pregnancy.

 Early symptoms include painless sores and rashes; untreated, it can damage the brain, heart, and nerves.

Modern Valentine’s Day link (practical, not symbolic): After Valentine’s Day, clinics often report spikes in:
* Syphilis
* Gonorrhea
* Chlamydia
* HIV

Reason: increased sexual activity and unprotected sex around the holiday.

Bottom line: The “Valentine’s Day disease” is syphilis by historical association, and Valentine’s Day itself is linked to higher STI transmission because of behavior, not biology.