Study finds widening inequalities in child vaccination rates across England

Inequalities in childhood vaccination are widening in England, with uptake rates of five key vaccines consistently lower in young children living in areas of higher deprivation from 2019 to 2023, finds a study published by The BMJ today.

The researchers say vaccine uptake was below the World Health Organization’s recommended 95% target for all vaccinations studied and call for urgent action to strengthen systems for childhood vaccination.

Protecting children from vaccine preventable diseases is a fundamental public health priority. The vaccination schedule in England protects children against 15 diseases including measles, diphtheria, whooping cough, polio, pneumonia and meningitis.

Records show that uptake rates of childhood vaccinations in England have been steadily declining over the past decade but few studies have looked at trends in inequalities.

To address this, researchers set out to assess the effect of socioeconomic deprivation on the uptake of five key vaccinations included in the childhood immunisation schedule in England from 2019 to 2013.

Their findings are based on general practice data for five key vaccines given to children aged up to 5 years in England between April 2019 and March 2023.

The vaccines were first and second doses of the measles, mumps, and rubella vaccine (MMR1 and MMR2), rotavirus vaccine, pneumococcal conjugate vaccine (PCV) booster, and six-in-one (DTaP/IPV/Hib/HepB) vaccine covering diphtheria, tetanus, pertussis (whooping cough), polio, Haemophilus influenzae type b, and hepatitis B).

For each general practice, changes in quarterly vaccine uptake were measured and compared by area deprivation level. Changes in inequality in vaccine uptake over time were also assessed using the slope index of inequality (SII).

The results show that for all vaccinations, the absolute difference in uptake between the least and most deprived groups increased over the study period.

For example, for the six-in-one vaccine, the absolute difference in vaccination uptake between the least and most deprived groups in the starting quarter was 3.3% and increased to 7.4% (4.1 percentage points) by the final quarter of data collection.

The absolute difference for rotavirus vaccination increased from 6.3% to 9.1% (2.8 percentage points), for PCV booster vaccination from 5.6% to 8.6% (3 percentage points), for MMR1 at age 2 years from 5.8% to 8.3% (2.5 percentage points), and for MMR2 at age 5 years from 5.3% to 11.5% (6.2 percentage points).

The most pronounced inequality was seen for the MMR2 vaccine given at age 3 years and 4 months, increasing from −9.6% to −13.4%.

The number of children susceptible to measles at age 5 by the end of the study period increased 15-fold, from 1,364 to 20,958, in the least deprived group and 20-fold, from 1,296 to 25,345, in the most deprived group. For rotavirus, a 14-fold increase, from 2,292 to 32,981, was seen in the least deprived group and a 16-fold increase, from 2,815 to 45,201, in the most deprived group.

Regional analysis showed that London had the lowest overall uptake of vaccination, followed by the Midlands and North West. London and the North West region also had greater inequality in vaccine uptake compared with southern regions.

Finally, vaccine uptake was below the recommended 95% WHO threshold throughout the study period for all vaccinations.

These are observational findings, and the researchers acknowledge various imitations including incorrectly recorded uptake rates in some areas, catchup vaccinations, being unable to include children who are not registered at general practices, or capture vaccinations delivered in private settings. Nor can they rule out the possibility that other unmeasured factors may have affected their results.

However, results were similar after further analysis of the data, providing greater confidence in the conclusions.

As such, they conclude: “These findings strongly support the urgent need for effective strengthening of vaccination systems, proportionate to levels of need, in addition to interventions and catchup campaigns in underserved populations.”