Discovery Health's ongoing analysis of daily vaccination rates among scheme members paints an interesting picture. How do scheme members' perceptions of risk of severe COVID-19 illness, or having had a prior COVID-19 infection, affect the likelihood of being vaccinated?
Shirley Collie (Chief Healthcare Analytics Actuary, Discovery Health) and Lizelle Steenkamp (Head of Risk Intelligence, Discovery Health)
Keeping up the pace of daily vaccinations is key to the success of South Africa's mass vaccination rollout for COVID-19. Discovery Health has invested significantly in supporting the success of this national effort, through dedicated mass vaccination sites and through ongoing analysis of vaccine uptake trends within the administered member base and more broadly.
Vaccination trends among Discovery Health administered medical scheme members
From 17 May (the start of South Africa's mass vaccination campaign) to 28 November 2021, daily rates of vaccinations administered across age groups within Discovery Health's administered medical scheme member base have declined.
- By 28 November 2021, just under two thirds (61.1%) of all adult scheme members (over the age of 18) had been either partially or fully vaccinated for COVID-19 and just over 10% (11.3%) of all children between the ages of 12 and 17 had been either partially or fully vaccinated for COVID-19.
- At the current rate of vaccination, it will take a further 213 days for 95% of the adult Discovery Health population to have received at least one vaccine dose.
We set out to investigate three key areas of interest
- The 7-day moving average of daily vaccinations. Are rates plateauing (staying the same with no changes) or declining?
- Which clinical categories of members are likely to be vaccinated? This analysis looked at scheme members':
- "COVID-19 personal resilience risk index" - a tool developed by Discovery Health to assist scheme members to estimate their risk of hospitalisation if they contract COVID-19. The tool classifies members as being in a "high" or "low" resilience category according to age, chronic illness profile and frequency of physical activity. Members who are in the low resilience category have a high risk of admission to hospital if they contract COVID-19 (and vice versa for members who are in the high resilience category). Members in the latter category tend to be in a younger age group, exercise frequently, or have no or few chronic conditions.
- History of documented prior infection. A documented COVID-19 infection is based on PCR results data.
- Vitality status: Discovery Health Vitality clients are on statuses Blue, Bronze, Silver, Gold and Diamond, with Diamond policyholders being consistently engaged on the Vitality Health programme, and achieving the highest threshold of points for completing relevant health checks, undertaking regular exercise, and selecting a basket of healthy food items, whereas clients on Blue status are the least engaged.
- Is there any variation in vaccination rates in people over the age of 60 in various municipalities across South Africa?
Are vaccination rates plateauing or declining across each age group?
(a) Proportion of members vaccinated, by age group
Figure 1 shows the proportion of scheme members vaccinated by 20 September 2021 across age groups. It also shows the plateau in vaccination rates in each age band since 17 May 2021 (the start of South Africa's mass vaccination campaign).
- People vaccinated for COVID-19 before 17 May 2021 were vaccinated under the Sisonke COVID-19 trial. The trial focused on healthcare workers and certain staff members within the healthcare sector. This trial was not open to the public at large. This cohort received the single-dose Johnson & Johnson COVID-19 vaccine.
By 28 November, 77.6% of Discovery Health clients aged 60 years and older had been either partially or fully vaccinated. This age group has been eligible for vaccination since 17 May 2021, the start of South Africa's mass vaccination campaign.
By 28 November (three months after they became eligible for vaccination), 44.1% of scheme members aged 18 to 34 had had a COVID-19 vaccine dose. On 28 November, the 7-day average daily vaccination rate was at 1 710 doses, down from the 7-day average daily vaccination rate of 15 083 doses seen since 20 August 2021 (when this group eligibility opened).There has been a much slower take up on vaccines for children aged 12 to 17, with only 11.3% of children in this age group having been vaccinated as at 28 November (a month after they became eligible for vaccination).
Figure 1 and 2: Proportion of Discovery Health clients vaccinated (either partially or fully) by age band over time
(b) 7-day daily average of COVID-19 vaccines administered across age groups
Figure 2 reflects the 7-day daily average of COVID-19 vaccines given to scheme members between 17 May 2021 and 28 November 2021.
The data shows:
- A decline in the number of daily vaccinations administered to scheme members aged 60 and over - from a high of 9 892 daily vaccinations recorded between 15 and 21 July, to just under 280 daily vaccine doses on 28 November 2021.
- Vaccinations opened to this age group from 17 May, accounting for the rise in vaccinations at that time and through to the end of July 2021.
- Two peaks in daily vaccination rates for scheme members aged 50 to 59:
- The first between 3 and 9 July with 11 457 daily vaccinations administered
- The second between 15 and 21 August with 10 506 daily vaccinations administered
- Registrations for COVID-19 vaccination opened to this age group from 1 July.
- For scheme members aged 35 to 49, a decline from 13 844 vaccinations administered daily in the week of 18 July, to 1 431 vaccinations administered daily by 28 November 2021.
- Registrations opened to this age group from 15 July.
- In scheme members aged 18 to 34, the number of daily vaccinations administered reached a peak of 15 083 for the week ending 26 August and has since seen a sharp decline to 1 710 daily vaccinations at 28 November 2021.
- Registrations opened to this age group from 20 August.
- In scheme members aged 12 to 17, the number of daily vaccinations administered reached a peak of 1 776 for the week ending 26 October, and has since seen a sharp decline to 606 daily vaccinations on 28 November 2021.
- This group was most recently eligible for vaccination with registration open from 20 October.
The highest number of vaccinations administered on a single day, across all age bands occurred on 20 August.
On this day, cumulatively 51 529 scheme members were vaccinated for COVID-19. This peak happened to coincide with the opening of vaccination eligibility to people aged 18 to 34 years on 20 August. Publicity in this regard may account for the high demand for vaccines on this day.
Figure 3: Daily 7-day average of vaccine doses for Discovery Health clients by age band
Which clinical categories of members are likely to be vaccinated?
(a) Is risk of serious COVID-19 illness a driver of vaccine uptake?
Figure 4 shows the way in which scheme members whose "COVID-19 personal resilience risk index" score is low are more likely to be vaccinated (across age categories). This suggests that members who perceive themselves as being at risk of severe COVID-19 related outcomes (admission to hospital), are likely more motivated to be vaccinated for COVID-19.
Adult scheme members with a low COVID-19 personal resilience risk index score are between 2% to 19% more likely to be vaccinated than individuals with a high resilience score.
Figure 4: Proportion vaccinated by resilience index category across age groups
(b) Recovery from COVID-19 illness - a deterrent of vaccine uptake?
Figure 5 indicates the proportion of scheme members who have had a documented prior COVID 19 infection since the start of the pandemic. It distinguishes between unvaccinated and vaccinated scheme members, dividing them by age category.
The analysis shows that 12% of currently unvaccinated scheme members are people who have recovered from a past COVID-19 infection.
In contrast, only 11% of vaccinated members have had COVID-19 before. This difference is greater in older age bands.
Overall, scheme members aged 40+ years who have had a documented prior COVID-19 infection are 29% less likely to be vaccinated than those who have not tested positive for COVID-19. Further analysis is being done to delve into the reasons for this trend.
Figure 5: Proportion with prior infection by vaccination status
(c) Are members with a higher Vitality status (typically are more engaged in healthy behaviours) more likely to be vaccinated?
Gold and Diamond Vitality status policyholders are considered to be more engaged with positive health screening and lifestyle behaviours, whereas Blue and Bronze Vitality members are less engaged. Figure 6 below shows that the higher the Vitality status of a client, the more likely they are to be vaccinated across age categories.
Figure 6: Proportion vaccinated members by Vitality status across age categories
Is there any variation in vaccination rates in people over the age of 60 in various municipalities across South Africa?
Figure 7 shows the regional variation of vaccine uptake in South Africa, both within and across provinces. The analysis includes municipalities where more than 5 000 administered scheme members, who are over age 60, reside.
Figure 7: Proportion vaccinated by municipality for Discovery clients aged 60 years and older
There is some regional variation in vaccination rates:
- Johannesburg has the highest vaccination rate at 81.8%
- Sedibeng has the lowest vaccination rate at 65.7%
In the Western Cape:
- Overberg has the highest vaccination rate at 82.9%.
- West Coast has the lowest vaccination rate at 77.5%
- eThekwini has the highest vaccination rate at 81.9%
- Ugu has the lowest vaccination rate at 75.0%
In summary, we observe a decline in the daily vaccination rates across all scheme member age categories. At current vaccination rates, it will take a further 324 days for 95% of the Discovery Health administered scheme member adult population to be partially or fully vaccinated for COVID-19 and a further 411 days for 95% of the child (ages between 12 and 17) Discovery Health population to have received at least one vaccine dose
Perceptions of risk of severe COVID-19 related clinical outcomes drive vaccination rates. On the other hand, having had and recovered from COVID-19 seems a deterrent to vaccination, and we are exploring this further. We see that the more health-conscious our clients are, as measured by a higher Vitality status, the more likely they are to get vaccinated.
There may be several factors contributing to the observed regional variation in vaccination rates, including but not limited to, access, rate of prior infection, and vaccine hesitancy levels. The plethora of misinformation in relation to COVID-19 disease and vaccines has caused great confusion in the public mind about how best to protect oneself from exposure to the disease and how to approach vaccination.
Likely, the decline in daily vaccination trends seen across all age groups in the Discovery Health administered scheme member base is linked to the general COVID-19 vaccine hesitancy phenomenon.
In this case, many people who are pro-vaccines, in general, may be hesitant when it comes to COVID-19 vaccines. They seek answers to questions about vaccine effectiveness and safety (risk of serious side-effects) and more along these lines.
At Discovery Health we are doing all we can to empower people with facts about COVID-19 and vaccines. We do this through our COVID-19 hub, COVID-19 vaccine hub, public-facing webinars, media communications and more. We will continue our efforts to support administered scheme members in making informed decisions around being vaccinated for COVID-19. We will also continue to support the national mass vaccination rollout through our Discovery-run vaccination sites and other related efforts, in partnership with provincial and national Departments of Health.
Interested in knowing more or reporting on these findings?
Please contact us on MEDIA_RELATIONS_TEAM@discovery.co.za to request any updated data available since publication and any further context required.
All information shared on this page is based on perspectives gained from analysis of figures and trends emanating from Discovery Health's data pool. The analysis, which is conducted by Discovery Health's actuarial and data scientist team, aims to encourage industry dialogue. This content shared is for educational and informational purposes only.