Below is a link to an essay on the use of the phrase “global public goods”. The essay focuses on the three papers Paul Samuelson wrote in the 1950s that are often used, and misused, to define public goods. Samuelson’s own papers were more inclusive and nuanced that would be suggested by the frequent citing of the “extreme” and “polar” [his words] case used for his 1954-5 definition for a “pure” public good.
The issue for COVID 19 is, can goods that are rival in consumption or excludable be defined as “public goods?” I think that Samuelson’s 1954 and 1958 papers make it pretty clear that he would say yes.
https://www.indiachinainstitute.org/2020/07/09/the-use-and-abuse-of-global-public-good/
The Use and Abuse of the Phrase “Global Public Good”
James Love, July 9, 2020.
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The essay refers to three papers by Paul A. Samuelson. They are:
“The Pure Theory of Public Expenditure,” The Review of Economics and Statistics, Volume 36, Issue 4 (Nov., 1954), 387-389. (Jstor link)
“Diagrammatic Exposition of a Theory of Public Expenditure,” The Review of Economics and Statistics, Vol. 37, No. 4 (Nov., 1955), pp. 350-356 (Jstor link)
“Aspects of Public Expenditure Theories,” The Review of Economics and Statistics, Vol. 40, No. 4 (Nov., 1958), pp. 332-338 (Jstor link)
Note the progression of titles:
1954: “The Pure Theory of Public Expenditures”
1955: “a Theory of Public Expenditure”
1958: “Public Expenditure Theories”