Chicken Pox
Cards (16)
- Chicken Pox
- Caused by a virus called varicella zoster.
- In the 16th century, an English physician Richard Morton gave the name Chicken Pox.
- William Heberden proved chicken pox is different from smallpox.
- Varicella Zoster Virus
- Also known as human herpesvirus 3 (HHV3).
- Belongs to the herpesvirus family.
- The envelope is interspersed by spikes made up of viral glycoproteins.
- The VZV genome is double-stranded DNA coiled upon a protein axis.
- Varicella Zoster can cause to distinct lesions:
- Chickenpox: Primary Lesion.
- Herpes Zoster: Reactivated Lesion.
- Pathogenesis
- Day 0-3: Infection of conjunctivae and mucosa of the upper respiratory tract.
- Viral replication in regional lymph nodes.
- Day 4-6, primary viremia, viral infection in liver, spleen and other organs.
- Day 10-12, secondary viremia.
- Day 14, infection of skin and appearance of vesicular rash.
- First Exposure
- Body first exposed creates antibodies: IgG IgM IgA
- B & T memory cells are created.
- If the virus is in the body again, memory cells will detect it.
- Transmission
- Inhalation
- Tiny droplets.
- Stages
- Incubation period usually 14-17 days.
- Promode (1-3 days).
- Vesicles.
- Pustules.
- Scabs.
- Recovery typically 7 days after rash appears.
- Oral Transmission
- Small blister
- mucosal lesion
- Small blister-like lesions occasionally involve the oral side mucosa chiefly the buccal mucosa, tongue, gums and palate as well as the mucosa of the pharynx.
- The mucosal lesions, initially slightly raised vesicles with surrounding erythema, rupture soon after formation and form small eroded ulcers with a red margin.
- Increased Risk of Complications
- Normal Adults
- Immunocompromised
- Pregnant Woman
- Chickenpox Vaccine 1st dose - 12-15 months of age.
- Chickenpox Vaccine 2nd Dose - 4-6 years of age (may be given earlier of 3 months gap after 1st dose).
- People not been vaccinated earlier - People 13 years of age and older should get 2 doses at least 28 days apart.