Pharyngo conjunctival fever is caused by?
**Core Concept**
Pharyngoconjunctival fever (PCF) is a highly contagious, viral illness characterized by conjunctivitis, pharyngitis, and fever. It is primarily caused by adenovirus types 3 and 7, which are transmitted through close contact or contaminated water.
**Why the Correct Answer is Right**
Adenovirus types 3 and 7 are the primary causative agents of PCF. These viruses replicate in the epithelial cells of the conjunctiva, pharynx, and respiratory tract, leading to inflammation and clinical manifestations. The virus is highly contagious and can be spread through respiratory droplets, contact with contaminated surfaces, or contaminated water.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not specify a virus, and PCF is a viral illness, not bacterial or fungal.
**Option B:** This option is incorrect as it refers to a different type of adenovirus that causes a different disease, such as epidemic keratoconjunctivitis.
**Option C:** This option is incorrect as it refers to a bacterial infection, not a viral one.
**Clinical Pearl / High-Yield Fact**
PCF is highly contagious and can spread rapidly in crowded settings, such as schools or military barracks. It is essential to practice good hygiene, including frequent handwashing and proper disposal of contaminated materials, to prevent the spread of the disease.
**Correct Answer: D. Adenovirus types 3 and 7.**