Dutch study identifies trends driven by socioeconomic factors

In the Netherlands, the National Immunization Programme (NIP) was established in 1957. This program provides free and voluntary vaccinations against 13 serious infectious diseases and has drastically reduced child and young adult mortality across the country. However, recent trends show a decline in vaccination coverage, particularly for the diphtheria and tetanus toxoids and acellular pertussis and inactivated poliovirus vaccine (DTaP-IPV) and measles, mumps and rubella (MMR) vaccines.

While 95% of Dutch children born between 2008 and 2010 received vaccines against MMR and DTaP, coverage dropped successively over the years, and only 88–89% of children born in the Netherlands in 2020 were vaccinated.

In their study published in Eurosurveillance, Joyce Pijpers and colleagues identified several sociodemographic factors contributing to the observed decline in vaccination rates, including lower parental education, income, and migration background of parents. The retrospective cohort study used several data sources looking at more than 2.3 million children born between 2008 and 2020, a total of 2,323,838 children for MMR and 2,331,199 for DTaP-IPV.

By the age of two years, 94% of children (2,174,229) had received the MMR vaccine, and 93% (2,172,402) had received the DTaP-IPV vaccine. Among the 2,319,001 children eligible for both vaccines, 97% had matching vaccination status. This meant they either received both vaccines or neither. Meanwhile, 1.4% were vaccinated only for MMR, and 1.3% only for DTaP-IPV.

General decline in vaccination coverage in the Netherlands reflects broader European trends

Coverage for the first dose of the measles-containing vaccine in the EU/European Economic Area (EEA) decreased from 95% in 2018 to 92% in 2022. Common explanations for declining coverage include distrust in vaccines and governmental organizations, misinformation, and the influence of social media. These issues were reportedly exacerbated during the COVID-19 pandemic.

As outlined in this study, in 2022, in the Netherlands, trust in governmental institutions was below pre-pandemic levels, especially among individuals with lower maternal education levels, and was associated with lower COVID-19 vaccine uptake. Parental perceptions of childhood vaccination also became slightly more negative after the pandemic, although the decline in the coverage had already begun earlier.

Social media was seen to play a significant role in spreading misinformation regarding vaccinations. Research on Dutch Twitter activity in 2019 showed how anti-vaccine narratives gained traction and influenced public opinion. Selective exposure to this type of content reinforces negative attitudes, and the unregulated nature of online anti-vaccine messaging increases the risk of uninformed decision making.

Decline in vaccination coverage is more pronounced in specific population groups

The most substantial declines in vaccination rates for MMR and DTaP-IPV were observed among Dutch children of non-Dutch origin, children not attending daycare, those with self-employed mothers, and children in the lowest income households. According to the study results, children of Moroccan, Turkish, Dutch-Caribbean, and Surinamese origin showed notably lower vaccination coverage.

Qualitative studies have provided further insight into the reasons behind lower vaccination coverage among Dutch children with a migration background. As outlined in this study, results of a focus group in 2015 among parents of Moroccan and Turkish origin identified barriers such as difficulty understanding NIP information, limited consultation time, and challenges accessing vaccination centers.

Children not attending daycare also showed lower vaccination coverage. Vaccination is not required for daycare attendance in the Netherlands. Nevertheless, in these settings, parents are often asked about their child’s vaccination status, which was seen to potentially influence their vaccination decision making. Given the close contact among children in daycare settings, higher vaccination coverage in these environments would be beneficial for preventing future outbreaks.

Children from larger families (four or more children) had lower vaccination coverage than those from smaller families. This may be explained, in part, by the higher prevalence of large households within Orthodox Protestant communities, where vaccine hesitancy is more common. While lower income was historically associated with larger family size, recent trends suggest that higher income is becoming an increasingly important factor for having more children, particularly among mothers.

As outlined in this paper, systematic reviews have consistently found lower routine childhood vaccination coverage among children with lower parental socioeconomic status. In high-income countries, economic disparities in vaccine uptake are often linked to perceived risks, trust in government and health care professionals, and vaccine confidence, rather than financial access.

Addressing the decline in childhood vaccination: A call for targeted action

The findings in this paper highlight not only a general downward trend in vaccination uptake but also widening disparities among sociodemographic groups, with children of non-Dutch origin, those from lower-income households, and those not attending daycare being disproportionately affected. These patterns increase the risk of localized outbreaks, especially where unvaccinated children are socially clustered.

The researchers state that “social clustering potentially creates environments where infections spread more easily. Therefore, further research to investigate networks of unvaccinated and nonimmune individuals is needed to assess the risk of spread of vaccine-preventable diseases.”

As this paper outlines, further research is needed to understand the underlying causes affecting vaccine uptake among lower socioeconomic groups. Addressing misinformation, rebuilding trust in public institutions, and ensuring equitable access to vaccination services will be critical to reversing these trends and safeguarding children’s health across all segments of society.

Provided by
European Centre for Disease Prevention and Control (ECDC)