Summary of "(고) 학교 감염병 바로알기_수두"

Scientific concepts, discoveries, and nature/biological phenomena

Chickenpox is reported as one of the top three infectious diseases in schools in Korea.
Case numbers peak during school semesters (March–June, and October–December) and decline during breaks.

Chickenpox is caused by Varicella-Zoster Virus (VZV).
The virus was first cultured from blister material of patients with chickenpox and shingles in 1954.
A chickenpox vaccine was developed in the 1970s.

Primary routes
- Droplets/secretions and saliva from an infected person (e.g., cough secretions)
- Inhalation of aerosols produced from chickenpox blisters
- Direct contact with the rash
Effect of proximity
- Transmission is stronger when blisters are closer to the exposed lesion.
When spread stops
- Spread does not occur once blister lesions become scabs.
Infectious window
- From 1 day before rash/blister onset until about 5 days after rash appears.

Incubation period: average 14–16 days
Early sign: a generalized rash, often with itching
- Typically starts on the head, then spreads to the trunk
- Trunk rash is most frequent
Skin evolution
- Blisters burst or become cloudy before forming scabs
Systemic symptoms
- Malaise/itching and high fever for 2–3 days
- Recovery often occurs over a few weeks
Re-infection in general
- Usually not again after natural infection, implying long-lasting immunity in most cases

Routine vaccination schedule
- Given to children at 12 months of age
Catch-up vaccination
- For children under 13 if unvaccinated
- For adolescents 13+: vaccination given at intervals of 4–8 weeks
Breakthrough infection
- Chickenpox can occur about 40 days after vaccination even after immunization
- Breakthrough cases typically have milder symptoms than chickenpox from unvaccinated infection:
  - Possible absence/low-grade fever
  - Fewer rashes
  - Less progression to blisters
  - Sometimes no scabs/bumps, which can lead to missed diagnosis

After chickenpox, VZV does not leave the body completely.
It persists in nerve ganglia and can reactivate when immunity weakens (e.g., aging or immunosuppressant use).
Shingles presents as a rash along affected nerve pathways, often with severe pain.
Key concept: the same VZV can cause both chickenpox and shingles.

Case numbers rise during periods of increased mixing (school terms) and decrease during school breaks.
COVID-19 era mitigation measures (masking, distancing, controlling in-school density, and changes in reopening timing) were associated with reduced outbreaks.

Both can cause rash and may be confused early due to similar-looking lesions.
Monkeypox features
- Rashes tend to progress with multiple stages occurring together (initial rash, blisters, scabs)
- In comparison, chickenpox is more sequential (blistering then scabbing)
Transmission differences
- Chickenpox: respiratory/airborne-type spread (described as more contagious in classroom-like settings)
- Monkeypox: primarily contact transmission and spreads more slowly

Professor Lee Jae-gap (Department of Infectious Diseases, Hallym University Kangnam Sacred Heart Hospital)
Korea Ministry of Education (School Infectious Disease Surveillance Information Control, 2019)
Korea Centers for Disease Control and Prevention (KCDC) (mentioned in relation to 2014 data)
Disease Control Agency (mentioned for capital city trend analysis over the past five years)