Introduction: The COVID-19 pandemic has affected all aspects of human conditions of all nations, but some nations such as Brazil, India the United States had suffered disproportionately in terms of the total number of COVID-19 cases and COVID-19-related deaths. We investigated how the COVID-19 pandemic affected the transplantation of vital organs such as hearts and dispensable organs such as kidneys. We also investigated how the pandemic affected transplantation of these organs in developed counties where illegal kidney trading is absent, and in less developed countries including countries where illegal kidney trading had been reported.

Methods: Data on heart and kidney transplantation and per capita GDP in 2015-2020 were obtained from the Global Observatory on Donation and Transplantation (GODT) database and the World Trend Plus database, respectively. The effects of COVID-19 were tested using exploratory data analysis and nonparametric significance test using Wilcoxon Signed Rank test. The outcomes for 2020 were predicted using the Neural Network forecast method and the predicted outcomes were compared with actual cases using the nonparametric method and Wilcoxon Signed Rank test. A p-value <0.05 was considered statistically significant.

Results: The countries were clustered based on per capita GDP into three groups (Group 1: Australia, Denmark, Norway, Sweden, Switzerland, and United States; Group 2: Belgium, Finland, France, Germany, Hong Kong, Israel, Italy, Japan, Kuwait, Slovenia, South Korea, and the United Kingdom; and Group 3: Argentina, Belarus, Brazil, Bulgaria, China, Croatia, Iran, Mexico, Pakistan, Romania, Russia, and Turkey). COVID-19 has negatively affected the transplantation of both vital and dispensable organs. For hearts, the effect is statistically significant in group 2 and 3 countries but nonsignificant in Group 1 countries. For deceased kidneys, the effect is statistically significant in group 2 and 3 countries, but nonsignificant in Group 1 countries. For live donor kidneys, the effect is statistically significant in group 1 and 3 countries but not non-significant in Group 2 countries. For kidneys from both sources, the effect is statistically significant in group 3 countries, but nonsignificant in Group 1 and 2 countries.

Conclusions: Overall, the COVID-19 pandemic has more severely affected transplantation medicine in less developed countries compared to developed countries. Multiple factors, including health care infrastructures and overall national response to the COVID-19 pandemic, might have affected transplantation medicine during the COVID-19 pandemic. Further analyses of the impacts of COVID-19 can be helpful for preparedness in confronting future pandemics and reducing the impacts of the pandemics on healthcare including transplantation medicine.