Even before the pandemic, mental healthcare systems in most countries have historically been under-resourced and disorganised in their service delivery.

“Meeting the added demand for mental health services due to Covid-19 will be challenging, but taking no action should not be an option,” Santomauro added.

Until now, no study had analysed the global impact of the Covid-19 pandemic on prevalence of major depressive disorder and anxiety disorders in 2020.

To reach this conclusion, a systematic literature review was performed to identify population survey data published between January 1, 2020, and January 29, 2021. The systematic review identified 5,683 unique data sources, of which 48 (one of which reported across two regions) met the inclusion criteria.

Most studies were from Western Europe (22) and high-income North America (14), with others from Australasia (5), high-income Asia Pacific (5), East Asia (2), and Central Europe (1).

The meta-analysis indicates that increased Covid-19 infection rate and reduced movement of people were associated with increased prevalence of major depressive disorder and anxiety disorders, suggesting that countries hit hardest by the pandemic in 2020 had the greatest increases in prevalence of the disorders.

In the absence of the pandemic, model estimates suggest there would have been 193 million cases of major depressive disorder (2,471 cases per 100,000 population) globally in 2020.