COVID-2019 was first identified in Wuhan, China, at the end of 2019, and from there it spread worldwide. Due to this worldwide distribution of COVID-19 cases, the WHO declared a COVID-19 pandemic. The pathogen of COVID-19, a novel corona virus, resembles SARS-CoV, the pathogen of SARS (severe acute respiratory syndrome, a pandemic in 2003), so the International Committee on Taxonomy Virology named it SARS-CoV-2. However, COVID-19 is a different disease from SARS, and should be controlled to the extent possible with the effective vaccines and therapeutic medicines.

Although one year has passed since the first appearance of the disease, the number of COVID-19 cases continues to increase, and the pandemic is now in its third large wave. It is thought that it will be difficult to eradicate the disease completely, because SARS-CoV-2 is possible to invade and live in various host animals in addition to humans.

During this pandemic, the JDR has put together the special issue “COVID-19 and Historical Pandemics.” Because there have been many pandemics that have transformed society in various ways, the special issue includes historical pandemics in addition to COVID-19. The manuscripts in this issue include various subjects related to COVID-19, including methods of analyzing the pandemic, suggestions for countermeasures against it, methods of prevention and epidemiological reviews, among others.

The WHO has released a large volume of pandemic information on an ongoing basis, including its “COVID-19 Weekly Epidemiological Update.” In the weekly edition of December 27, it reported the cumulative number of cases and percentages of the global total from around the world: the Americas 34,403,371 (43%), Europe 25,271 (31%), Africa 1,831,227 (2%), and the Western Pacific 1.059,751 (1%). It is notable that 74% of cumulative global total number of cases have been reported in the Americas and Europe, where most developed countries are included, whereas the numbers in Africa, which includes many developing countries, and the Western Pacific region, which includes Thailand, the Philippines, Vietnam, and Malaysia in addition to Japan and China, are 2% and 1%, respectively. This indicates that the COVID-19 pandemic is a different from previous epidemics caused by other infectious diseases.

As the pandemic spreads, the JDR plans to edit Part 2 of this COVID-19 special issue.