Background There may be a difference in the number of articles about COVID-19 and SARS-CoV-2 between low- and middle-income countries (LMICs) and high-income countries (HICs). Methods We analyzed authors’ affiliations from 36 432 articles related to COVID-19 and SARS-CoV-2. We introduced logarithmic density and compared the number of articles and logarithmic density of LMICs with those of HICs. Results The number of articles and the logarithmic density of LMICs were lower than those of HICs (p<0.0001 for both). Conclusions There was a disparity in the number of articles related to COVID-19 and SARS-CoV-2 between LMICs and HICs.

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