Definition

1. Adjective:

   • Infectious / Contagious: Describes a disease, condition, or influence that can be transmitted from one person, organism, or thing to another, typically through direct or indirect contact.
   • Transmissible: Capable of being passed on or spread.

2. Verb (less common):

   • To infect / To transmit: The act of causing something, especially a disease or an idea, to spread to others.

Usage Examples

• Adjective:
  • Cúm là một bệnh truyền nhiễm. (Influenza is an infectious disease.)
  • Sự lạc quan của cô ấy thật sự truyền nhiễm. (Her optimism is truly contagious.)
• Verb:
  • Loại virus này có thể truyền nhiễm qua không khí. (This type of virus can be transmitted through the air.)

Advanced Usage

• Used in formal, medical, and sociological contexts to describe the spread of pathogens, emotions, behaviors, or information.
• "bệnh truyền nhiễm": infectious disease; contagious disease.
  • Các bệnh truyền nhiễm thường được kiểm soát bằng vắc-xin. (Infectious diseases are often controlled by vaccines.)

Variants and Related Words

• Lây nhiễm (v): to infect, to become infected.
  • Vi khuẩn có thể lây nhiễm qua vết thương hở. (Bacteria can infect through open wounds.)
• Sự truyền nhiễm (n): infection, transmission.
  • Sự truyền nhiễm của bệnh đã được ngăn chặn. (The transmission of the disease has been contained.)

Synonyms

• Contagious: (of a disease) spread by direct or indirect contact.
• Infectious: (of a disease or its cause) likely to be transmitted through the environment.
• Communicable: (of a disease) able to be transmitted from one person to another.

Related Idioms

• Truyền nhiễm thói quen: to pass on a habit (metaphorical use).
  • Anh ấy truyền nhiễm thói quen đọc sách cho cả nhóm. (He passed on the habit of reading to the whole group.)