10 Infection Risks of Kissing Strangers (Reminder Version)

Brothers, the world outside is dangerous—take care of yourselves.

1. Direct exchange of saliva is one of the most efficient ways to transmit flu and cold viruses.
2. Oral herpes (HSV-1) can be transmitted asymptomatically—even if the other person doesn’t have visible sores, you can still get infected.
3. EB virus (“kissing disease”) is highly transmissible and may cause fever, fatigue, and sore throat, with an incubation period of 2–6 weeks.
4. The mouth contains a huge number of bacteria (tens of billions); kissing can transfer bacteria related to periodontitis and cavities.
5. If the other person has oral ulcers, you’re basically exchanging bacteria from open wounds directly onto your oral mucosa.
6. Kissing strangers significantly increases the risk of oral HPV infection (which is linked to some oropharyngeal cancers).
7. Alcohol reduces the germ-killing ability of saliva, so kissing after drinking further increases the risk of bacterial transmission.
8. The bacterial environment in public places is uncertain—you have no idea if the other person just ate, smoked, or how clean their mouth is.
9. If the other person has Helicobacter pylori (HP), kissing is one of the main transmission routes.
10. Upper respiratory infections (laryngitis, tonsillitis) from the other person can be directly transmitted through saliva.