Childhood vaccinations are a very effective public health intervention to prevent infectious diseases. Timely uptake is essential to protect children against infectious diseases before they interact with more children outside of their households, and to keep high levels of the population vaccinated to prevent disease. Many outbreaks are partially explained by children not receiving vaccine at the recommended time.
An earlier study showed that maternal mental health is a determinant of lower vaccine uptake at the age of five. However, it is not clear when childhood vaccines actually get delayed. It is not known whether previous mental health issues or new issues in pregnancy or after birth are more important for affecting vaccine uptake, or at what ages in early childhood vaccines are most likely to be delayed.
In this study, we aim to discover different time-patterns of vaccine receipt in early childhood and their determinants including maternal mental health. This will aim to advise a more targeted public health intervention based on pre-existing or new maternal mental health diagnoses, delivered at the right time in the childhood vaccination scheme to prevent vaccine delay.
Childhood vaccinations are an effective public health intervention. Uptake of childhood vaccines is declining in the UK and vaccine-preventable infections are increasing, with the UK losing its measles elimination status in 2019. Surveillance focuses on uptake of each vaccine at ages one, two and five, less is known about timeliness of vaccination or patterns of combined vaccine uptake.
Recent outbreaks have been partially explained by children not receiving their vaccine on time. A study by Osam et al. (2020) showed that maternal mental health issues are predictive of lower vaccine uptake at the age of five. It is not known whether pre-existing or new antenatal or postnatal mental health issues are most relevant, or whether this underestimates vaccine delay which may be caught up by age 5.
In this historical cohort study of children born between January 2004 and February 2015, we aim to describe different time-patterns of vaccine receipt in early childhood and the role of maternal mental health on vaccine timeliness. We will look at common mental disorders, severe mental illness, and substance use disorder in mothers as different exposures, and distinguish between pre-existing mental health issues from first records in the antenatal and postnatal periods.
We will use a survival analysis-based approach to model vaccine receipt and estimate maternal mental health as a determinant of vaccine timeliness. We will explore deprivation as potential mediator, and region, ethnicity, maternal age, deprivation, and number of siblings as potential confounders.
Overall, this aims to advise a targeted public health intervention based on pre-existing or new maternal mental health diagnoses, delivered at the right time in the childhood vaccination programme to prevent ongoing vaccine delay.
Primary outcomes: Timing of vaccines routinely recommended at 8, 12, 16 weeks, one year and three years and four months after birth.
Charlotte Warren-Gash - Chief Investigator - London School of Hygiene & Tropical Medicine ( LSHTM )
Anne Suffel - Corresponding Applicant - London School of Hygiene & Tropical Medicine ( LSHTM )
Charlotte Warren-Gash - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
David Osborn - Collaborator - University College London ( UCL )
Helena Carreira - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
Jemma Walker - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
Sandra Mounier-Jack - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
CPRD Mother-Baby Link;HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation;Practice Level Index of Multiple Deprivation;Pregnancy Register