Fears of infection. Loneliness. Worries about physical health.

As the coronavirus spread across borders early in the pandemic, calls to global helplines showed a striking similarity in the toll on mental health — from Lebanon to China, Finland to Slovenia.

An analysis of 8 million calls to helplines in 19 countries, published in Nature, reveals a collective response to unprecedented, uncertain times.

Callers' worries centered on fears of infection, loneliness and physical health. Calls about relationship issues, economic problems and suicide-related issues were generally less prevalent than before the pandemic.

The Swiss and German researchers looked at helplines in Lebanon, 14 European countries, the United States, China, Hong Kong and Israel.

They included suicide-prevention hot lines and ones providing crisis counseling.

"We were struck by how similar the broad evolution of helpline call patterns looked across nations,'' said Marius Brulhart, a University of Lausanne economics professor and the study's lead author.

Pooling country-specific data during the pandemic's first 12 weeks in 2020, the researchers found that call volumes peaked at six weeks, rising 35% above calls during the same period in 2019.

Strict lockdown and social distancing measures were linked with more calls due to fear, loneliness and suicidal thinking or behavior.

Analyzing helpline data is "an incredibly creative way to assess mental health in the pandemic'' in an array of countries, she said.

Concerns raised in the calls echo results from surveys showing the pandemic's toll on mental health, said Judith Bass, of Johns Hopkins' Bloomberg School of Public Health.

"The idea that fear was part of the early manifestations both makes research sense but also logical sense,'' Bass said. The virus "was an unknown that nobody had experienced before.''