Older people in South Africa and excess mortality during the COVID-19 pandemic

Mar 1, 2021 | All posts, Opinions and contributions

By Peter Lloyd-Sherlock, Leon Geffen, Gabrielle Kelly and Lucas Sempe

Estimates of excess all-cause mortality are the most effective way to assess the impact of COVID-19 mortality on people of all ages, including older adults. Robust estimates can take into account that not all deaths caused by COVID-19 will be registered or attributed to that cause. They also include indirect mortality effects of the pandemic, such as deaths caused by reduced treatment for other health conditions. All of this is especially important for low and middle-income countries (LMICs) where death registration tends to be less complete and cause of death data less reliable than in high-income countries.

Other Global Platform blogs and papers refer to the poor coverage and quality of COVID-19 mortality data for older people in many LMICs [1, 2]. In some cases, depending on data availability, there is potential to generate robust estimates of excess deaths caused by the pandemic.  To date, few countries have done this on a regular or systematic basis and few have included specific analysis of people at older ages.

South Africa has not published age-breakdowns for reported COVID-19 deaths since 13 June 2020, perhaps due to concerns about the reliability of cause of death data. Instead, the South African Medical Research Council in partnership with the University of Cape Town Centre for Actuarial Research has been providing weekly updates on excess mortality. These include comparisons between people aged under 60 and those aged 60 and over [3]. Their analysis is based on a robust methodology and takes incomplete death registration into account (which not all excess mortality estimates do).

The main purpose of this blog is to draw attention to these weekly reports. Here are some highlights from the report that covers the period from 3 May 2020 to 6 February 2021, along with some additional comments.

Over this period, the total number of excess deaths from natural causes totalled 137,731. This compares to a total of 45,902 reported COVID-19 deaths over the same period. In simple terms, the number of all-age excess deaths was three times the number of reported COVID-19 deaths. This is a much larger difference than those reported for high-income countries. For example, separate studies of the USA show differentials of between 28 and 33%. [4, 5]. The most likely explanation for the large differential in South Africa is that many COVID-19 deaths are either unregistered or are wrongly attributed to other causes.

Of these excess deaths in South Africa, 103,748 (75.3%) occurred among people aged 60 or more. For the reasons given above, these are likely to be mainly caused by COVID-19 (either single-handedly or in combination with other risk factors, such as diabetes, HIV or TB) [6, 7].

Like many countries, South African is currently experiencing a second wave of COVID-19 mortality, with rates that are higher than during the earlier one. During the first five weeks of 2021, excess natural cause deaths of all ages totalled 54,774, 40% of the cumulative death total since 3 May 2020.

Some more general points can be taken from these data.

First, more caution should be exercised when trumpeting the apparent successes of some sub-Saharan African countries in keeping COVID-19 deaths at low levels [8]. There may be some truth in this, but the South African experience suggests that the majority of COVID-19 deaths have gone undetected and unreported. Sadly, health and population registration systems in most of the region are much less developed than South Africa and this also prevents robust estimates of excess mortality. Relatedly, even LMICs with high numbers of reported COVID-19 deaths, such as Brazil, India or Mexico, may be capturing a much smaller share of the true death toll than high-income countries are able to.

Second, the South African data indicate the degree to which the risk of excess mortality is linked to older age. People aged 60 or over make up 8.4% of the national population, but account for 75% of excess deaths. Other studies have noted that people at younger ages account for up a larger share of reported COVID-19 deaths in LMICs than in high-income countries [9]. This is a dangerous and potentially misleading conclusion to draw for countries where most COVID-19 deaths appear to go unreported. Diagnosing cause of death is especially challenging for older people with multiple health conditions, so under-reporting is likely to more frequent at older ages [10].

In sum, the two main take-home messages from these South Africa data are (i) under-reporting of COVID-19 deaths is much more common than in high-income countries and (ii) older people account for the great majority of these unreported deaths.


REFERENCES

  1. Peter Lloyd-Sherlock (2020) The United Nations World Data Forum recognises the deplorable state of data on older people and COVID-19. https://corona-older.com/2020/12/02/the-united-nations-world-data-forum-recognises-the-deplorable-state-of-data-on-older-people-and-covid-19/
  2. Lloyd-Sherlock, A.Guntupali, M.Mckee and L.Sempe (2020) Problems of data availability and quality for Covid-19 and older people in low and middle-income countries. The Gerontologist 61(2):141-44.
  3. Bradshaw, R.Laubscher, R.Dorrington, P.Groenewald and T.Moultrie (2020) Report on weekly deaths in South Africa. 31 January to 6 February 2021 (week 5). South African Medical Research Council and UCT Centre for Actuarial Research. https://www.samrc.ac.za/sites/default/files/files/2021-02-10/weekly6Feb2021.pdf
  4. Weinberger DM, Chen J, Cohen T, Crawford FW, Mostashari F, Olson D, et al. Estimation of Excess Deaths Associated with the COVID-19 Pandemic in the United States, March to May 2020. JAMA Internal Medicine. 2020;06520(May):E1–9.
  5. Woolf SH, Chapman DA, Sabo RT, Weinberger DM, Hill L. Excess Deaths from COVID-19 and Other Causes, March-April 2020. JAMA – Journal of the American Medical Association. 2020;324(5):E1–3.
  6. Andrew Boulle, Mary-Ann Davies, Hannah Hussey, Muzzammil Ismail, Erna Morden, et al (2020) Risk factors for COVID-19 death in a population cohort study from the Western Cape Province, South Africa. Clin Infect Dis. 2020 Aug 29 : ciaa1198.
  7. WHO (2020) Nearly 1 in 5 COVID-19 deaths in the African region linked to diabetes. https://www.afro.who.int/news/nearly-1-5-covid-19-deaths-african-region-linked-diabetes
  8. Lawal Y. Africa’s low COVID-19 mortality rate: A paradox? Int J Infect Dis. 2021 Jan;102:118-122. doi: 10.1016/j.ijid.2020.10.038. Epub 2020 Oct 16. PMID: 33075535; PMCID: PMC7566670.
  9. Demombynes, Gabriel. 2020. COVID-19 Age-Mortality Curves Are Flatter in Developing Countries. Policy Research Working Paper; No. 9313. World Bank, Washington, DC. https://openknowledge.worldbank.org/handle/10986/34028
  10. Kung S, Doppen M, Black M, Braithwaite I, Kearns C, Weatherall M, et al. Underestimation of COVID-19 mortality during the pandemic. ERJ Open Research [Internet]. 2020 Dec;00766–2020. Available from: http://openres.ersjournals.com/lookup/doi/10.1183/23120541.00766-2020