Changes in the Epidemiology of Rubella: The Influence of Vaccine-Introducing Methods and COVID-19

Area of Science:

• Public Health
• Infectious Diseases
• Epidemiology

Background:

• Rubella is a viral infection posing risks, particularly congenital rubella syndrome in newborns.
• Rubella is vaccine-preventable, with routine immunization programs in place globally.
• The United States eliminated endemic rubella in 2004, while Japan has experienced recent outbreaks.

Purpose of the Study:

• To analyze the reasons behind recent rubella outbreaks in Japan.
• To investigate the impact of differing rubella immunization strategies between Japan and the United States.
• To identify factors contributing to rubella susceptibility in specific populations in Japan.

Main Methods:

• Comparative analysis of rubella immunization policies and introduction timelines in Japan and the US.
• Epidemiological review of recent rubella outbreaks in Japan.
• Assessment of vaccination coverage and susceptibility rates among different demographic groups in Japan.

Main Results:

• Japan's initial strategy of vaccinating only junior high school girls led to high rubella susceptibility among males.
• This targeted approach resulted in significant rubella outbreaks in Japan.
• The coronavirus pandemic has also influenced rubella epidemiology.

Conclusions:

• Differences in routine rubella immunization introduction contributed to recent outbreaks in Japan.
• Measures are being implemented in Japan to reduce rubella susceptibility in unvaccinated males.
• Adjusting vaccination strategies is crucial for controlling rubella outbreaks and preventing congenital rubella syndrome.