There’s a new breakthrough this week in the search for what causes long COVID — the lingering and often disabling symptoms that last for months, even years after a COVID infection — including intense fatigue, breathing problems, heart palpitations and brain fog.

Long COVID has been around since COVID first emerged in 2020, but much is still unknown about what causes it and how to treat it.

But researchers from the University of Pennsylvania just published a new study suggesting that there may be a connection between low serotonin levels and long COVID.

We hear from Elizabeth Cooney, who’s reported on this for our partners at STAT News, the health and medicine publication.

This article was originally published on WBUR.org.

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