History repeats itself in Japan: Failure to learn from rubella epidemic leads to failure to provide the HPV vaccine

Human Papillomavirus Vaccination by Birth Fiscal Year in Japan

Importance

The Ministry of Health, Labour, and Welfare (MHLW) of Japan aggregates human papillomavirus (HPV) vaccination data across Japan for each fiscal year (FY) by age at vaccination. Birth FY (BFY)-specific vaccination coverage remains unknown.

Objective

To calculate the BFY-specific vaccination coverage for each FY and the cumulative first-dose coverage for each BFY in Japan, to understand the generation-specific vaccination coverage, and to estimate the cumulative first-dose coverage of each BFY that would be achieved by FY 2028 vs World Health Organization (WHO) targets.

Design, Setting, and Participants

In this cross-sectional study, MHLW-published national age-specific HPV vaccination numbers and demographic data for female individuals were used to calculate the BFY-specific first-dose coverage for each FY and the BFY-specific cumulative first-dose coverage. It was assumed that the BFYs 2007 to 2012 vaccination coverage in FY 2023 to 2028 would remain the same as the vaccination coverage of the same grade in FY 2022 to estimate the cumulative first-dose coverage that would be achieved by FY 2028. Data analysis was performed from December 2023 to January 2024.

Exposure

Two MHLW policy changes were the government's suspension of proactive recommendation for HPV vaccination in June 2013 and the government's resumption of proactive recommendation for HPV vaccination in April 2022.

Main Outcomes and Measures

The primary outcome was generation-specific vaccination coverage among female individuals born in BFYs 1994 to 2010 in FYs 2010 to 2022, calculated using reconfigured published data.

Results

In this study of vaccination data for 9 414 620 female individuals, the generation-specific vaccination coverage was 71.96% for the vaccination generation (BFYs 1994-1999), 4.62% for the vaccine-suspension generation (BFYs 2000-2003), 16.16% for the generation that received information individually (BFYs 2004-2009), and 2.83% for the vaccine-resumed generation (BFY 2010). HPV routine vaccination coverage was extremely low in BFYs 2000 to 2010 (0.84%-25.21%) vs BFYs 1994 to 1999 (53.31%-79.47%). The cumulative first-dose coverage that was estimated to be achieved in the vaccine-resumed generation by FY 2028 plateaued at 43.16%.

Conclusions and Relevance

Even after the resumption of MHLW's proactive recommendations, HPV vaccination coverage has only minimally recovered in Japan. The cumulative first-dose coverage that was estimated to be achieved in the vaccine-resumed generation by FY 2028 is below the WHO target. These findings reveal that stronger cervical cancer control measures are required, particularly for the vaccine-resumed generation, which will plateau at approximately one-half the WHO target values.

Nurturing Deep Tech to Solve Social Problems: Learning from COVID-19 mRNA Vaccine Development

In mRNA vaccines against COVID-19, a new technology that had never been used for approved drugs was applied and succeeded in rapid clinical use. The development and application of new technologies are critical to solving emerging public health problems therefore it is important to understand which factors enabled the rapid development of the COVID-19 mRNA vaccines. This review discusses administrative and technological aspects of rapid vaccine development. In the technological aspects, I carefully examined the technology and clinical development histories of BioNTech and Moderna by searching their publication, patent application and clinical trials. Compared to the case of Japanese company that has not succeeded in the rapid development of mRNA vaccine, years of in-depth technology research and clinical development experience with other diseases and viruses were found to have enhanced BioNTech and Moderna's technological readiness and contributed to rapid vaccine development against COVID-19 in addition to government administrative support. An aspect of the investments that supported the long-term research and development of mRNA vaccines is also discussed.

Corowa-kun: A messenger app chatbot delivers COVID-19 vaccine information, Japan 2021

Background

There is a long history in Japan of public concerns about vaccine adverse events. Few studies have assessed how mobile messenger apps affect COVID-19 vaccine hesitancy.

Methods

Corowa-kun, a free chatbot, was created on February 6, 2021 in LINE, the most popular messenger app in Japan. Corowa-kun provides instant, automated answers to 70 frequently asked COVID-19 vaccine questions. A cross-sectional survey with 21 questions was performed within Corowa-kun during April 5–12, 2021.

Results

A total of 59,676 persons used Corowa-kun during February–April 2021. Of them, 10,192 users (17%) participated in the survey. Median age was 55 years (range 16–97), and most were female (74%). COVID-19 vaccine hesitancy reported by survey respondents decreased from 41% to 20% after using Corowa-kun. Of the 20% who remained hesitant, 16% (1,675) were unsure, and 4% (3 6 4) did not intend to be vaccinated. Factors associated with vaccine hesitancy were: age 16–34 (odds ratio [OR] = 3.7; 95% confidential interval [CI]: 3.0–4.6, compared to age ≥ 65), female sex (OR = 2.4; Cl: 2.1–2.8), and history of a previous vaccine side-effect (OR = 2.5; Cl: 2.2–2.9). Being a physician (OR = 0.2; Cl: 0.1–0.4) and having received a flu vaccine the prior season (OR = 0.4; Cl: 0.3–0.4) were protective.

Conclusions

A substantial number of people used the chabot in a short period. Mobile messenger apps could be leveraged to provide accurate vaccine information and to investigate vaccine intention and risk factors for vaccine hesitancy.

Persistence of anti-rubella immunoglobulin G antibody titers in young adults involved in a short-term periodic immunization in Japan

In Japan, several rubella outbreaks in adults have erupted due to insufficient immunity against rubella virus (RUBV). Although selective immunization is being promoted in addition to a routine rubella vaccine program as a rubella eradication strategy, serosurveillance against RUBV needs to be implemented in the generations corresponding to the transition period of vaccination. In this study, a survey of anti-rubella immunoglobulin G (IgG) antibody titers was conducted among young adults involved in the transitional periods of the routine rubella vaccine program. Serosurveillance was performed in 370 healthy young adults aged 18-20 years, and their serum samples were analyzed using an enzyme immunoassay to determine rubella-specific IgG antibody titers. Although multiple regression analysis revealed significant differences only in medical history, more than 90% of participants exhibited seropositivity, excluding those who received single-dose vaccine alone. Based on elapsed periods after the last vaccination, rubella-specific IgG antibody titers in less than a 6-year period were higher compared to that in the more than 10-year period. Although almost all study participants in the transitional period had seropositivity, the results may indicate that the persistence of seropositivity is related to past rubella outbreaks.

The controversy on HPV vaccination in Japan: Criticism of the ethical validity of the arguments for the suspension of the proactive recommendation

The Human Papillomavirus (HPV) vaccine was integrated into Japan's national immunization program (NIP) in April 2013. However, numerous instances of serious adverse reactions were widely reported in the media, resulting in the Ministry of Health, Labor, and Welfare (MHLW) suspending the official recommendation of the HPV vaccine on June 14, 2013. Investigating the reported incidents, the Vaccine Adverse Reactions Review Committee (VARRC)-an MHLW advisory committee-found no high-quality evidence supporting a causal relationship between the reported events and the HPV vaccination. However, rather than lifting the suspension, they have opted to maintain a "pseudo informed consent" confirming the perceptions of Japanese citizens regarding the vaccine. Accordingly, there appears to be a fundamental difference in the approach to vaccine policymaking between Japan (MHLW/VARRC) and other countries and the World Health Organization, which base policy decisions on the effectiveness and safety of the vaccine. Consequently, the arguments for the suspension of the HPV vaccine recommendation are not ethically appropriate. Relevant bodies must make a clear decision regarding the HPV vaccine and its status in the NIP: the proactive recommendation must either be reinstated or the HPV vaccine legal framework altered to rely entirely on voluntary individual decisions.

Predicting congenital rubella syndrome in Japan, 2018-2019

OBJECTIVES

A rubella epidemic has been ongoing in Japan since August 2018. In the present study, we aimed to predict the likely size of a congenital rubella syndrome (CRS) epidemic during 2018-19.

METHODS

The expected number of CRS cases was estimated using an integral equation based on age-specific incidence of rubella among adult women, the time delay from gestational age of infection to diagnosis of CRS, and distribution of the mothers' age at delivery. We used epidemic data during 2012-14 to parameterize the model and applied this in the prediction for 2018-19.

RESULTS

In analyzing the 2012-14 epidemic data, the mean delay from the mother's infection to diagnosis was estimated at 24.2weeks (95% confidence interval (CI): 20.7, 28.1). Applying the parameterized model, together with the more than 480 rubella cases in women in 2018 as well as delayed mother's age at delivery in 2017, we determined that the expected number of CRS cases would be 9.7 (95% CI: 6.5, 12.5) cases. As the epidemic is ongoing, the cumulative number of CRS cases could potentially reach 96.8 (95% CI: 65.3, 125.5) cases, if rubella cases in adult women rose to 10 times the number by week 49 in 2018.

CONCLUSIONS

CRS is expected to occur an average of 24weeks following the mother's infection with rubella virus. Accounting for an increase to 650 cases in women by week 5 in 2019, the expected number of CRS cases during 2018-19 has already exceeded 13 cases, as of week 5 in 2019.