Pre-School vaccination booster uptake in a semi-rural General Practice.

Flora Williams Burton Sherwood Forest Hospitals Trust; Larwood Health Partnership

1. Introduction

The childhood vaccination programme has been key for the protection from, and eradication of, many pathogens. This includes the now very rare smallpox and polio, but also diphtheria, tetanus, pertussis, polio, measles, mumps and rubella (1). These have been specified due to the current UK government vaccination schedule (2), according to which a pre-school booster vaccination of diphtheria, tetanus, pertussis, and polio (dTaP) and measles, mumps, and rubella (MMR) should be given at 3 years 4 months old or soon after.

However, uptake is variable within communities, and although Quality Outcomes Framework (QoF) guidance is set at 87% uptake, vaccination rates are often lower. There can be many reasons for this, though a significant one is due to the fact that they are so successful – high vaccination rates have made dangerous illnesses seem rare, and so the public no longer view them as a threat. When patients and parents believe the benefit of vaccination to be low, the perceived risks often outweigh these benefits, and so children are not vaccinated (1).

The focus of this audit is on patients who have, versus patients who have not, had their pre-school booster vaccination for diphtheria. This has been chosen as it forms part of the pre-school booster programme and has not had as much media coverage as other vaccinations (i.e., MMR), thus less misinformation is in the public domain. Diphtheria has a high transmission rate, and even with optimal treatment can be fatal in up to 10% of cases. Prior to vaccination, it killed approximately 35000 children per annum in the UK. Although cases are now exceedingly rare, there have been 2 fatalities in Europe since 2015 (3).

2. Criteria and standards

Patients included in this audit were those aged 3 years and 4 months to 5 years old at the time of data collection. The assessed outcome was that they must have a vaccination containing diphtheria within the previous 20 months. A vaccination containing diphtheria was set as the assessment marker for having received the dTaP vaccine, and the time limitations set excludes original vaccination as last dose given at 16 weeks (4 months).

The standard for patients vaccinated was set at 87%. This is based on the Quality and Outcomes framework for 2021/2022, which sets childhood vaccination targets at 87-95%(4). There has been no change for 2022/2023(5). This standard has been chosen due to its relevance in the context of a semi-rural General Practice (GP).

3. Methodology

Using the SystmOne clinical reporting, a report was created of all patients aged 3 years 4 months to 5 years, and all patients aged 3 years 4 months to 5 years with an entry of diphtheria containing vaccination within last 20 months (from feb1 2023). Microsoft excel was used to extrapolate data such as percentages and numbers not vaccinated.

4. Results

On 1st February 2023, there were 634 children aged 3 years 4 months to 5 years old registered with the practice. 489 (77%) had had a vaccine containing diphtheria in the preceding 20 months, and 145 (23%) had not (Figure 1). This falls below the QoF standard of 87% by 10%, or 64 children (Figure 2).

5. Discussion

Kaufman et al (6) conducted a systematic review in 2021 of barriers to childhood vaccination. They found six prominent recurring themesAccess, Clinic or Health System Barriers, Concerns or Beliefs, Health Perceptions and Experiences, Knowledge and Information, and Social or Family Influences.

Concerns and Beliefs encompassed the most barriers. Highlights from this category are concerns around the safety of vaccines, and a lack of trust in the healthcare system and/or government. This can be demonstrated by the MMR vaccination and autism scare in the late 1990s. Authored by Wakefield in 1998, a case study of 12 patients implied a correlation between the vaccine and a novel syndrome consisting of GI and developmental disease. The paper had no control category and relied heavily on parental recall. Godlee, Smith, and Marchovitch (7) argue that this was deliberate fraud in their 2011 editorial. The original paper was noticed by the media, and resulted in an all time low vaccination rate for MMR. Despite the paper now being declared as fraudulent and retracted, the damage remains in many communities.

Communication was the largest barrier in the Clinic or Health system category and covers problems such as vaccination not being explicitly recommended by healthcare practitioners. This is an important factor to consider when planning an intervention.

Access barriers highlights issues such as time and expense. Outside of the NHS, vaccinations can be expensive, but that would not be relevant to this audit. Other challenges under this heading that may apply to this patient population include waiting times and childcare for siblings.

Although the other categories may have points where an intervention would help uptake, the above are the easiest to target and therefore most relevant for this audit.

6.1

To attempt to increase vaccination uptake, a text message was sent to all (guardians of) patients who were due their vaccinations. There were two patients who were not sent this message, one due to no number on file and one who had not consented to being sent SMS. Additionally, a poster was put on the screens in the waiting room.

Data collection was completed 6 weeks after the initiation of intervention. I used the same search using SystmOne clinical reporting. This showed that in the current age group of 3 years 4 months to 5 years old, 534 out of 662 children had had their preschool vaccinations, which equates to 80.7% (Figure 3).

Using an online chi-squared calculator (8), the chi-square statistic is 3.5531. The p-value is 0.059434. This is not significant as p > 0.05. The chi-square statistic with Yates correction is 3.3039. The p -value is 0.069116. Again, this is not significant as p > 0.05.

These have different total population values as they are snapshots in time, however I also followed up my original data group. Of the original 648, 559 were now vaccinated. Using this data and the same chi-squared calculator (8), the chi-square statistic is 20.8118. The pvalue is < 0.00001, which is significant as p < 0.05. The chi-square statistic with Yates correction is 20.1665. The p -value is < 0.00001. This is again significant as p < 0.05.

8. Limitations

This method does not exclude patients with contraindications to vaccination, and does not confirm that they also had the MMR vaccine. This study was done within a single GP surgery at a single point in time, and the intervention period was limited to 6 weeks, due to rotation of staff.

9. References

1. Torracinta, L., Tanner, R., & Vanderslott, S. (2021). MMR vaccine attitude and uptake research in the United Kingdom: A critical review. Vaccines 9(4), 402. https://doi.org/10.3390/vaccines9040402

2. Gov.UK. (2022, February 17). Routine childhood immunisations from February 2022 (born on or after 1 January 2020). Retrieved January 28, 2023, from https://www.gov.uk/government/publications/routine-childhood-immunisation-schedule/routine-childhood-immunisationsfrom-february-2022-born-on-or-after-1-january-2020

3. Oxford Vaccine Group, The University of Oxford. (2018, May 31). Diphtheria. Vaccine Knowledge Project. Retrieved February 2, 2023, from https://vk.ovg.ox.ac.uk/diphtheria#Key-disease-facts

4. NHS. (2022, October 18). Quality and Outcomes Framework guidance for 2021/22. NHS choices. Retrieved January 28, 2023, from https://www.england.nhs.uk/publication/update-on-quality-outcomes-framework-changes-for-2021-22/

5. Gault, B. (2022, July 27). Qof 2022/23: What practices need to know. QOF 2022/23: What practices need to know. Retrieved February 2, 2023, from https://managementinpractice.com/practice-intelligence/finance/qof-2022-23-what-practices-need-to-know/

6. Kaufman, J., Tuckerman, J., Bonner, C., Durrheim, D. N., Costa, D., Trevena, L., Thomas, S., & Danchin, M. (2021). Parent-level barriers to uptake of childhood vaccination: A global overview of Systematic Reviews. BMJ Global Health 6(9). https://doi.org/10.1136/bmjgh-2021006860

7. Godlee, F., Smith, J., & Marcovitch, H. (2011). Wakefield's article linking MMR vaccine and autism was fraudulent. BMJ 342(jan0511), c7452–c7452. https://doi.org/10.1136/bmj.c7452

8. Stangroom, J. (2023). Chi-square calculator. Social Science Statistics. Retrieved April 19, 2023, from https://www.socscistatistics.com/tests/chisquare/default2.aspx

7. Discussion Part 2: Post-intervention

From the original population, even considering the passage of time we can see a large number of patients were vaccinated in the 6 week interval between the two sets of data collection. To ascertain whether this would have happened naturally with time, I would need to compare with historical data, but due to differences in coding over time, plus the covid-19 pandemic, this data is likely to be unreliable. Overall, this suggests that the individual texts sent were an efficient intervention at encouraging vaccination.

When compared to the data using the same search at a different time point, we see that there is much less of an increase in vaccination, although an increase still exists. Possible reasons for this include the fact that new patients coming in to the age bracket would not have received the SMS, or that the poster was not effective.

Within the population covered by this GP surgery, there is a large Polish community, some of whom have limited English. Something to consider is whether providing the poster or other resources in a different language would aid uptake. Additionally, texts were only send to those who were eligible for the vaccination, but would sending a message to those who are about to become eligible increase early uptake?