CANBERRA - Mental health problem driven by the COVID-19 pandemic in the United States was both prevalent and persistent, Australian news website The Conversation has reported.

More than one fifth of the US adults reported probable depression in both spring 2020 and spring 2021, said the report, citing a study conducted by researchers from Boston University.

The national study in March 2020 measured mental health and assets, when 27.8 percent of the American adults reported symptoms of depression, such as losing interest in activities or feeling down or hopeless. The number was more than three times as high as the national pre-pandemic depression estimate of 8.5 percent.

"Most striking to us was that a year into the pandemic, depression rates remained high, despite hopeful signs of reducing infections and deaths," said the report.

In April 2021 when people were receiving vaccine shots and doctors were looking for better COVID-19 treatments, the rate of adults reporting symptoms of depression rose to 32.8 percent.

"Worse yet, that higher 2021 number included 20.3 percent who had reported symptoms of depression both in April 2020 and in April 2021. This finding suggests that poor mental health driven by the pandemic was both prevalent and persistent," it said.

"Nearly one million US lives have been lost to COVID-19, and there have been almost five million hospitalizations," said the report. "We believe the pandemic's sustained impact on the nation's mental health is unprecedented."