International collaboration during the COVID-19 crisis: autumn 2020 developments.

After the initial shock of the early months of the global COVID-19 pandemic, international collaboration in COVID-19 research continues to show aberrant patterns compared to coronavirus research in pre-COVID times. The most affected nations tend to produce the greatest number of coronavirus articles, with output closely coupled to the rate of infection. COVID-19 research has fewer nations and smaller teams than pre-COVID research, a trend which intensifies throughout the pandemic. The United States remains the single largest contributor to the global publication output, but contrary to China's dominance in the initial months of the pandemic, China's contribution falls as the national COVID-19 caseload drops. China-USA collaborations drop as the pandemic continues, perhaps due to China's reduced rate of publication on the topic, and perhaps due to political obstacles, or a combination of these factors.