Where new cases of the Delta variant of COVID-19 came from remains a mystery - but it has been revealed two Australians had ...

The delta variant is fueling the COVID-19 surge in the United States, but experts warn that a more dangerous variant could emerge if more Americans don't get vaccinated. Delta is the most recent of ...

The World Health Organization and the Centers for Disease Control and Prevention have both designated beta as a “variant of ...

Over the past several years, monitoring the transmission fitness of emerging SARS-CoV-2 variants has been critical for pandemic forecasting and public health response. However, existing methods, such ...