[edited to correct JMA board member, not health minister]
[edited to correct JMA board member, not health minister]
If you're referring to the Elgazzar paper from Egypt (as the "population studies in [..] Africa"), then it has been withdrawn from pre-print distribution. [2]
And, in general, the studies that have been performed are not sufficient to support ivermectin use among the general public at this time. [3]
[1] https://factcheck.afp.com/http%253A%252F%252Fdoc.afp.com%252...
[2] https://www.theguardian.com/science/2021/jul/16/huge-study-s...
[3] https://www.the-scientist.com/news-opinion/ivermectin-still-...
Ozaki is on the JMA Board https://www.med.or.jp/english/about_JMA/trustees.html
The population study I was referring to was this one: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S...
citation 3 is an opinion piece (opinion section of that magazine). And even as a persuasion piece, it still quotes Cochrane on the need for a serious study.
I posted it not because I care about its point of view, but because it was one of the first items I was able to find quickly which provides a synopsis of what I was looking for: the origins of the ivermectin hypotheses in respect to COVID.