South Korea and Germany are the two countries that have responded best to COVID-19 around the globe. Both countries have implemented wide-scale testing and contact tracing. Germany even traced its first community case back to a salt shaker.
Even with the scale of testing with contact tracing in Germany and South Korea; the reported death rate in Germany is 3.11% and in South Korea is 2.18%.
Certainly improved testing will continue to properly define the exact number of infections in the U.S. and elsewhere. I expect improvements over the upcoming months which will help defined the exact death rate and R0 for COVID-19.
From a death rate perspective it becomes a question of which grows at a greater rate -- the numerator with previously uncounted deaths being added to the COVID-19 total, or the denominator with the total number of positive infection cases.
De Prado is saying the the 3.11% and 2.18% that you mentioned above are grossly overestimated because the number of confirmed infections are only a fraction of the actual infections. This has been the case historically as well with other diseases. He provides H1N1 as an example. The initial fatality rate was 5.1%. The real number is 0.02%.
In case you are not familiar with de Prado, below is his bio:
Prof. Marcos López de Prado is the CIO of True Positive Technologies (TPT), and Professor of Practice at Cornell University’s School of Engineering. He has over 20 years of experience developing investment strategies with the help of machine learning algorithms and supercomputers. Marcos launched TPT after he sold some of his patents to AQR Capital Management, where he was a principal and AQR’s first head of machine learning. TPT is currently engaged by clients with a combined AUM in excess of $1 trillion. Marcos also founded and led Guggenheim Partners’ Quantitative Investment Strategies business, where he managed up to $13 billion in assets, and delivered an audited risk-adjusted return (information ratio) of 2.3.
Concurrently with the management of investments, since 2011 Marcos has been a research fellow at Lawrence Berkeley National Laboratory (U.S. Department of Energy, Office of Science). He has published dozens of scientific articles on machine learning and supercomputing in the leading academic journals, is a founding co-editor of The Journal of Financial Data Science, has testified before the U.S. Congress on AI policy, and SSRN ranks him as the most-read author in economics. Marcos is the author of several graduate textbooks, including Advances in Financial Machine Learning (Wiley, 2018), and Machine Learning for Asset Managers (Cambridge University Press, 2020).
Marcos earned a PhD in financial economics (2003), a second PhD in mathematical finance (2011) from Universidad Complutense de Madrid, and is a recipient of Spain's National Award for Academic Excellence (1999). He completed his post-doctoral research at Harvard University and Cornell University, where he is a faculty member. Marcos has an Erdős #2 according to the American Mathematical Society, and in 2019, he received the ‘Quant of the Year Award’ from The Journal of Portfolio Management.
Below is a link to the paper:
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3579712