Regular Articles
Subsidy Programs for Seasonal Influenza Vaccination of Children and Pregnant Women in Japanese Municipalities
2024 Volume 144 Issue 7 Pages 749-754
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2024 Volume 144 Issue 7 Pages 749-754
In Japan, influenza vaccination is offered to children and pregnant women at clinics or hospitals as an elective, self-funded treatment, as the vaccination is not included in the national vaccination subsidy program. However, some Japanese municipalities offer a discretionary subsidy for seasonal influenza vaccination of children and pregnant women as a local policy. We identified these local subsidy programs during 2019/2020 seasonal influenza season by conducting a cross-sectional survey across Japan. Out of a total of 1741 municipalities, responses were received from 1732; therefore, the response rate was 99.5%. The local influenza vaccine subsidy programs for children were offered in 45.7%, and for pregnant women in 10.2%, of Japanese municipalities. This is the first survey of subsidy programs for pregnant women. While policy diffusion of subsidy programs for children was observed during the 9 years since a previous study, such programs for pregnant women remain limited. Despite many municipalities having subsidy programs, we found that their provision still remains limited when viewed as a whole.
Vaccination is the most effective way to prevent infection and severe outcomes caused by influenza viruses.1) Vaccination is especially important for people at high risk of influenza complications and for those who live with, or care for, people at high risk. The World Health Organization2) recommends annual influenza vaccination for pregnant women at any stage of pregnancy, children aged between 6 months and 5 years, older people (aged over 65 years), individuals with chronic medical conditions, and healthcare workers.2)
In Japan, seasonal influenza vaccination for older people aged 65 years and over, and people aged 60–64 years with underlying diseases, is included in the national vaccination subsidy program as required by the Immunization Act3,4); however, children and pregnant women are not included in this subsidy program.3) Instead, influenza vaccination is offered at clinics or hospitals to children and pregnant women as an elective, self-funded treatment. In annual survey data in some regions from National Institute of Infectious Disease (NIID) by the Ministry of Health, Labour and Welfare, the uptake rate for the seasonal influenza vaccine was 54% in children aged 2–12 years during the 2019/2020 season.5)
Some Japanese municipalities offer a discretionary subsidy for the seasonal influenza vaccination to children and pregnant women. The decision regarding which population to target and the subsidy amount depends on each municipality’s specific policy and budget. From the residents’ perspective, the copayment amount may vary due to the differing levels of subsidy in each municipality. These local subsidy programs are not monitored by the central government. In 2010, a research survey was published6); however, the subsequent situation is not well known. In this study, we focused on the unique local subsidy programs for school-aged children and pregnant women. First, we identified municipalities offering seasonal influenza vaccination subsidy programs by conducting a cross-sectional survey across Japan. Second, we investigated the subsidy amount, as shown on local government official websites, and estimated the copayment for the vaccination in each municipality. Finally, the national expected level of copayment was estimated.
Japan has 47 prefectures, each consisting of a number of municipalities. To identify each municipality’s local vaccine subsidy program during the 2019/2020 influenza season, we conducted a questionnaire survey of 1741 municipalities in October 2019.7) The study was conducted in accordance with the ethical principles of medical research involving human subjects as stated in the 1964 Declaration of Helsinki, and was approved by the ethical committee of Tsukuba University (1440-1).
The questionnaire initially asked respondents whether the municipality had its own local subsidy program for seasonal influenza vaccination. If the answer was “yes,” then the questionnaire went on to query whether the program’s target population included preschool and school children (i.e., primary, junior high school, and high school level) and pregnant women. If no response to the questionnaire was received then non-responders were re-sent the questionnaire and were also followed up by telephone. In the analysis, we summarized the responses regarding each subsidy program’s target population, including preschool/school children and pregnant women. If, for example, a subsidy program was offered to a specific school age or age range, it was nevertheless still classified into the relevant category.
We next summarized the data for these municipalities as a proportion of all the municipalities in each of the 47 prefectures to reveal regional disparities; these were then represented with the 25% colored tiles on a map denoting the proportion of municipalities in each prefecture unit, using MANDARA10 software (KTGIS.net).
2. Estimated Copayment According to Published InformationWe conducted an information search on the official websites of municipalities that offered subsidy programs regarding the subsidy amount and/or copayment for the vaccination of children (aged ≤18 years) and pregnant women in the 2019/2020 influenza season. If information on either a fixed copayment amount or a fixed subsidy amount for each municipality was available, then the data were recorded. The copayment amount was then estimated using the model price for a dose of seasonal influenza vaccine, which was JPY 3500 (USD 1.00=JPY 140).8) In Japan, two doses are recommended for children under 13-year-old, which costs approximately JPY 7000 in total, and one dose for pregnant women.9)
Where the subsidy/copayment amount varied depending on age or school grade targets, the higher value of the subsidy amount or the lower value of the copayment amount was extracted. We recorded the subsidy amount regardless of whether it was provided only to specific age groups or school grades. A histogram was generated to reveal the differences in copayment among the municipalities.
3. Expected Level of Copayment at the National LevelWe estimated the national expected level of copayment from the target population in Japan by calculating a population-weighted mean according to municipality10); however, this estimation was not possible for pregnant women, as their numbers per municipality were not available. The estimation includes municipalities with no subsidy programs, for which the above-mentioned model prices were used. In the base case analysis, published data were included. The mean value of copayment was applied to the data in cases where published data were unavailable in the sensitivity analysis.
Out of a total of 1741 municipalities, responses were received from 1732; therefore, the response rate was 99.5%. Of the 1732 municipalities that responded, a local subsidy program was offered in 791 (45.7%) municipalities for preschool children, 745 (43.0%) for primary school students, 739 (42.7%) for junior high school students, 342 (19.7%) for high school students, and 177 (10.2%) for pregnant women (Table 1). The percentages of municipalities with a subsidy program according to prefecture were then represented on maps to reveal regional disparities (Fig. 1).
| Preschool children | Primary school students | Junior high school students | High school students | Pregnant women | |
|---|---|---|---|---|---|
| 1. Cross sectional survey | |||||
| Subsidy (yes, n), (%) | 791 (45.7) | 745 (43.0) | 739 (42.7) | 342 (19.7) | 177 (10.2) |
| 2. Information on the official website | |||||
| Fixed copayment amount (yes, n) | 155 | 152 | 158 | 99 | 56 |
| Median (range), JPY | 2000 (0–6000) | 2000 (0–6000) | 1000 (0–3000) | 1000 (0–3000) | 1000 (0–3000) |
| Fixed subsidy amount (yes, n) | 455 | 423 | 404 | 158 | 75 |
| Median (range), JPY | 3000 (1000–8000) | 3000 (1000–8000) | 2000 (500–5000) | 2000 (1000–5000) | 1500 (1000–4500) |
| Both (yes, n) | 20 | 20 | 23 | 14 | 6 |
*1 Subsidy proportion in municipalities within prefecture. *2 Total n=47. 1. Preschool children, 2. Primary school students, 3. Junior high school students, 4. High school students, 5. Pregnant women.
Based on publicly available information, the data for fixed copayment and fixed subsidy in each municipality were summarized separately; the data for estimated copayment in each municipality were also summarized. Only acquired data were utilized. Some municipalities published information for both fixed copayment and fixed subsidy; in such cases, both were counted separately.
2-1. Fixed copaymentInformation on the fixed copayment for preschool children was published by 155 municipalities out of 791, and the median (range) fixed copayment amount was JPY 2000 (JPY 0–6000). For the other target populations, the median (range) subsidy amounts were: JPY 2000 (JPY 0–6000) for primary school students (152/745), JPY 1000 (JPY 0–3000) for junior high school students (158/739), JPY 1000 (JPY 0–3000) for high school students (99/342), and JPY 1000 (JPY 0–3000) for pregnant women (56/177) (Table 1).
2-2. Fixed subsidyInformation on the fixed subsidy amount for preschool children was published by 455 municipalities out of 791, and the median (range) fixed subsidy amount was JPY 3000 (JPY 1000–8000). For the other target populations, the median (range) subsidy amounts were: JPY 3000 (JPY 1000–8000) for primary school children (423/745), JPY 2000 (JPY 500–5000) for junior school children (404/739), JPY 2000 (JPY 1000–5000) for high school students (158/342), and JPY 1500 (JPY 1000–4500) for pregnant women (75/177) (Table 1).
2-3. Estimated copaymentThe estimated copayments in each municipality were estimated using the model price and fixed subsidy amount according to target population. These estimations, including cases without subsidy programs, are presented as a histogram to reveal their distribution for each municipality (Fig. 2).
* Not available data was excluded. 1. For preschool children (for two shots) in one influenza season, 2. For primary school students (for two shots) in one influenza season, 3. For junior high school students (for one shot) in one influenza season, 4. For high school students (for one shot) in one influenza season, 5. For pregnant women (for one shot) in one influenza season.
The national expected copayment per person (sensitivity analysis) estimated according to target population was JPY 6488 (JPY 6296) for preschool children, JPY 6550 (JPY 6408) for primary school students for two vaccine doses, JPY 3215 (JPY 3187) for junior high school students, and JPY 3426 (JPY 3379) for high school students for a single vaccine dose.
This study explored local discretionary subsidy programs for seasonal influenza vaccination for children and pregnant women, organized by each municipality across Japan. To our knowledge, this is the first survey of subsidy programs for pregnant women.
According to a previous survey in 2010, approximately 10% of all municipalities offered a subsidy program for children aged 0–5 years, and approximately 9% offered it for children aged 6–12 years.6) We cannot directly compare these results with those of the current study due to the different target population definitions, such as the target age used in the survey; however, this study showed that a higher proportion of municipalities were offering subsidy programs than in 2010; 45.7% for preschool children (aged approximately 0–5 years) and 43.0% for primary school children (aged approximately 6–12 years). Even when viewed at the prefectural level, there were differences in the level of provision (Fig. 1), possibly owing to the effect of neighboring municipalities’ policies within the prefecture, as previous studies have indicated.11,12)
While subsidy programs for children are steadily expanding, they have not hitherto been investigated for pregnant women across Japan. We have found that provision is still scant, with only approximately 10% of municipalities offering such programs. Nevertheless, 38% of pregnant women have received the influenza vaccination as an elective prophylaxis according to research conducted in maternity hospitals and clinics,13) which indicates that most pregnant women pay the full cost of the vaccination. Seasonal influenza vaccination for pregnant women is an effective way of preventing infection in the mother and infant,13,14) and the cost-effectiveness of the vaccination has been shown in the Japanese context.15) Therefore, policy-makers in local governments should consider introducing seasonal influenza vaccination subsidy programs for pregnant women, to help reduce disease burden and utilize regional health resources efficiently.
The direct impact of the subsidy program on influenza vaccination coverage and health outcomes is not clear from the results in this study. However, financial support for households could be one of the factors that raise vaccine coverage in children,16) as parents incur the cost of these vaccinations, and such an expense might be burdensome to households with children and pregnant women.17) A report from the Hirosaki area of Northern Japan, which initiated their subsidy program free of charge in 2013 for the first influenza vaccination dose in preschool children aged over 6 months, estimates that the average vaccine uptake rate for these children during the provision of this subsidy program from 2013 to 2017 was approximately 75%.18) This was higher than the uptake rate in the annual survey data from the NIID (54%).5) In addition, the number of cases of influenza in preschool children per sentinel in the Hirosaki area was fewer than in other neighboring areas in the same prefecture following the introduction of the program.18) However, the impact of the program on influenza prevalence per fixed point is not clear. Further studies are required to investigate the relationship between influenza vaccine subsidy programs and health outcomes in the community.
According to the estimated and expected copayments in this study at a national level throughout Japan, and despite many municipalities having subsidy programs, these subsidy programs do not fully cover the target populations defined in our study.
LimitationsInitially, we planned this research with a two-stage survey design. The first survey was designed to screen for subsidy programs among all the municipalities across Japan, and the second survey was designed to explore the details of the subsidy programs as well as their performance within the screened municipalities. However, we abandoned the second survey to avoid overburdening the health center staff of the municipalities during the COVID-19 pandemic. Instead, we conducted an information search on the official websites of municipalities. Therefore, we could not collect information on all screened municipalities. Moreover, the subsidy programs may have since changed as a result of the COVID-19 pandemic, whereas this study describes the subsidy situation in the period just before the COVID-19 pandemic. Finally, we elected to summarize all the subsidies in a unified format; therefore, bias may have occurred in the estimation of expected copayment amounts.
Policy diffusion of influenza vaccination subsidy programs for children was observed during the 9 years since a previous study. The current study is the first to survey influenza vaccination subsidy programs for pregnant women, and we found that provision is still scant, with only approximately 10% of municipalities offering such programs.
We are grateful to all the staff in the municipalities who answered the questionnaire in this survey. This study was supported by a research grant for JSPS KAKENHI (19H03865, 17K09216) and Research on Emerging and Re-emerging Infectious Diseases, Health and Labour Sciences Research Grants from the Ministry of Health, Labour and Welfare, Japan (20HA2001).
The authors declare no conflict of interest.
