Financial hindrances to introducing higher-valent pediatric combination vaccines

KEYWORDS:

• Childhood immunization
• combination vaccine
• health inequity
• health system
• higher-valent vaccine
• medical impoverishment
• vaccine introduction

This article responds to:

Acceptance and willingness to pay for DTaP-HBV-IPV-Hib hexavalent vaccine among parents: A cross-sectional survey in China

Reply to “Financial hindrances to introducing higher-valent pediatric combination vaccines”

Dear Editor,

I read with interest the article ‘‘Acceptance and willingness to pay for DTaP-HBV-IPV-Hib hexavalent vaccine among parents: a cross-sectional survey in China’’ by Huang et al.¹ The authors highlighted the importance of introducing higher-valent pediatric combination vaccines into national immunization programs to improve vaccine acceptance, so as to harness their advantages over lower-valent vaccines. These advantages include requiring fewer injections, which can potentially reduce indirect costs and increase completion and compliance rates.² However, the direct costs of higher-valent vaccines can be higher. Thus, empirical evidence¹ on the need for sustainable immunization financing models is paramount for effective policy-making to realize equitable protection. The recent setbacks in childhood immunization in the context of the coronavirus disease 2019 pandemic, which increased the prevalence of and inequity in zero-dose and missed-dose children,³ makes research on immunization financing even more valuable.

This letter article argues that the financial difficulties of getting one’s children vaccinated go beyond the WTP for the vaccine. Parents’ WTP may reflect any or a combination of the following and/or other factors: (i) their financial security, (ii) the value they assign to vaccinating their children, and (iii) their level of tolerance of the potential resulting financial consequences. If, e.g., the WTP is not correlated with their income and is driven more by other factors, then there is a risk that parents’ out-of-pocket (OOP) financing of the vaccine could compromise basic needs, e.g., food, housing, and utilities (e.g., water, electricity, and fuel).⁴ This could result in medical impoverishment, even when WTP is high. This may be the case for the authors’ study, as suggested by the results of the Tobit model indicating no significant association between monthly income and WTP.¹

To improve the public health value of WTP, additional data and analytical steps might need to be considered. For instance, factoring relevant thresholds for catastrophic (i.e., exceeding a predetermined threshold⁵) and impoverishing (i.e., pushing the population below a poverty line⁵) OOP health expenditures into the estimation framework can improve the relevance of WTP for Sustainable Development Goal (SDG) indicators 3.8.2 and 1.1.1, respectively. For the former, the thresholds of 10% and 25% (of total household expenditure or income) are used to define ‘‘large household expenditure on health,” and for the latter, the international poverty line of US$2.15 a day at 2017 international price is used.⁴

Indirect costs for vaccination can also affect the policy value of WTP. These costs, e.g., with transport, may be substantial in certain settings and differ significantly across study settings. This can hinder the interpretation of WTP, thereby lessening its public health applicability and value for SDGs. In their analysis of WTP based on the payment card method, the authors¹ considered the direct costs of the hexavalent vaccine but did not include additional costs that a vaccination entails. However, if the indirect costs are substantial, they can also pose a substantial weight on the parents’ WTP for the vaccination. This can ultimately determine whether the WTP for the vaccine can translate into a vaccination. Accounting for geospatial data on the distance between each household and the nearest eligible health facility in the analysis may allow for higher resolution and consistency of the WTP estimates. If geospatial data are limited, the average cost to reach the nearest health facility could be used.

These considerations have consequential policy implications. If data availability difficulties can be addressed, then tackling the aspects discussed here could deliver a WTP that is more likely to be equitable and actionable. Thus, it can more effectively be used for policy-making and priority-setting to accelerate the attainment of universal immunization coverage while reducing the propensity for medical impoverishment. This could include, e.g., selecting priority sites for incorporating the vaccine into national immunization programs, that is, locations with low WTP where the direct costs could be paid for by the government to prevent or minimize OOP payments from parents and the associated public health consequences.

Abbreviations

DTaP	=	Diphtheria-tetanus-acellular pertussis
HBV	=	Hepatitis B virus
Hib	=	Haemophilus influenzae type b
IPV	=	Inactivated poliovirus
OOP	=	Out-of-pocket
SDG	=	Sustainable Development Goal
WTP	=	Willingness to pay

Authors’ contributions

FA contributed to conceptualization, methodology, software, validation, formal analysis, investigation, resources, data curation, writing – original draft, writing – review and editing, visualization, project administration, and funding acquisition. All authors read and approved the final manuscript.

Availability of data and materials

The datasets used in the current study are publicly available and can be efficiently extracted from the sources cited in the article.

Ethics approval and consent to participate

Ethics approval and consent to participate are not necessary because this research did not collect identifiable human material and data.

Disclosure statement

FA reports consultancy fees from the WHO.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.