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What you need to know about the data use in the ADH Resurgence Map

November 19, 2021

We use Our World In Data (OWID) data in the ADH Resurgence Map to show rise in COVID-19 case numbers, deaths, testing, vaccines, etc in 53 African countries. How does OWID collect this data? What are the limitations of this dataset?

Is the data open?

Yes, Our World In Data is open. Their data and supporting resources serve as a public good. The raw data is updated daily and available for download in CSV format.

Our data visualisations and copy are licensed under a Creative Commons Attribution 4.0 International License and freely available for use and embedding in others’ work. Users are encouraged to explore the data, download the resources, leave feedback, and contact us for more information.

How is the data collected?

OWID has dedicated teams of people collecting COVID-19 data from official reports and sources. The data is collected from a variety of sources including, the African Centers for Disease Control and Prevention (Africa CDC), National Health Ministries, United Nations, World Bank, Global Burden of Disease, Blavatnik School of Government, etc. You can find more information about the OWID data sources for each country here.

OWID has up-to-date Testing Data for less than half of Africa

Testing for COVID-19 is critical for measuring and tracking the resurgence of COVID-19. Positive COVID-19 tests equal the number of new confirmed COVID-19 cases, but there are likely to be many more unconfirmed cases of COVID-19 because not everyone with symptoms is tested. And not all test results are reported. OWID only includes PCR and antigen test results as these are reliable indicators of active cases at a given point in time. Antibody tests are less useful for this purpose because a positive result would mean that the person has had COVID-19 before but they are not necessarily infectious at the time of testing.

Testing data is used to calculate 5 indicators in the resurgence map related to new confirmed cases, and 4 indicators related to testing and positivity. Testing for COVID-19 is a significant cost for healthcare budgets.

“While poorer countries such as Cote d’Ivoire and Nigeria have done only a few tests per thousand people, richer countries like Australia, Denmark and the United Arab Emirates have done more tests than there are people in the country.”

(OWID website See more details here.)

In the map above, you can see how many African countries do not provide testing data for which OWID can report on. There are also significant gaps in the data collected and published. These gaps in data are highlighted with an exclamation mark in the ADH Resurgence Map. The leaderboard view of the resurgence map was designed to show at a quick glance which countries in Africa are experiencing a sudden increase in new COVID-19 cases. But because there are significant gaps in the data and some counties share their data infrequently, the leader board actually highlights which countries have suddenly uploaded data after a long period of not uploading any data at all. For example where an increase in new confirmed COVID-19 cases exceeds 200% it is likely that there was a sudden data dump. As a result the top ten and bottom 43 - 53 countries on the leaderboard include countries where significant gaps in the data are identified.

The infrequency of data uploads per country is best seen when you overlay new_confirmed_cases. See for example, the graph of Guinea-Bissau below. It shows new confirmed cases smoothed (represented by the line) compared to new confirmed cases in bars. We suggest that you look into whether the sudden increase in numbers of confirmed cases reflects a surge in cases or a data dump by the institutions collecting test results in that country.

New confirmed cases smoothed (represented by the line) compared to new confirmed cases in Guinea-Bissau .

On the dashboard, we have provided the OWID definitions for each indicator as per the OWID descriptions available in gitbook here. The data sources for each indicator are also given here. The additional explainers were researched and written by ADH with references where relevant.

For more detail about OWID data and the change log see:

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