Related Experiment Videos
A live varicella vaccine used for children in hospitals
Insights
A live varicella vaccine safely protected children, even those with underlying conditions. Early vaccination within 72 hours of exposure prevented varicella spread and offered two-year immunity.
Area of Science:
- Immunology
- Vaccinology
- Pediatrics
Background:
- Varicella (chickenpox) poses risks, particularly to hospitalized children with underlying diseases or on immunosuppressive therapy.
- Effective prevention strategies are crucial for controlling varicella outbreaks in vulnerable populations.
Purpose of the Study:
- To evaluate the safety and efficacy of a live varicella vaccine in hospitalized children.
- To assess the vaccine's ability to prevent varicella spread and its long-term immunogenicity.
Main Methods:
- Administered a live varicella vaccine to hospitalized children, including those with underlying conditions and on immunosuppressive therapy.
- Monitored vaccine recipients for adverse events and varicella incidence.
- Conducted a two-year follow-up study to assess antibody persistence and protection against natural varicella.
- Investigated the potential for transmission from vaccine recipients to susceptible individuals.
- Prepared and evaluated varicella skin antigen for susceptibility testing.
Main Results:
- The live varicella vaccine demonstrated safety and effectiveness in hospitalized children, including those on immunosuppressive therapy.
- Vaccination within 72 hours of varicella exposure effectively prevented disease spread in both hospital and home settings.
- A two-year follow-up confirmed sustained neutralizing antibody levels and protection against natural varicella infection.
- No evidence of transmission from vaccine recipients to susceptible children in closed institutions was observed.
- A prepared varicella skin antigen proved useful for determining individual susceptibility to clinical varicella.
Conclusions:
- The live varicella vaccine is a safe and effective tool for preventing varicella in hospitalized children.
- The vaccine can be used prophylactically to prevent varicella spread following exposure.
- Long-term immunity and lack of transmission from vaccinees support its widespread use.
Abstract:
A live varicella vaccine was developed and the following results obtained: 1. The vaccine was safely and effectively used for children in hospital with various underlying diseases; some of the children had been receiving immunosuppressive therapy. 2. Spread of varicella could be prevented by immediate inoculation of the vaccine in hospital or at home when vaccine was given to susceptible children within 72 hours after exposure. 3. Persistence of neutralizing antibody and prevention of natural varicella have been confirmed in a two-year follow-up study of the vaccine recipients. 4. No contact infection from vaccine recipients to susceptible children in closed institutions was detected (Asano et al., 1976). 5. Varicella skin antigen was prepared and was found useful for clinical purposes, e.g., by providing a convenient means of determining the susceptibility of individuals to clinical varicella.