Most of us know how important a good night’s sleep is for our physical and mental health. This is especially true as we live through the COVID-19 pandemic, but for many sleep has become increasingly difficult.

Three-quarters of U.K. residents reported changes in their sleep habits during the initial lockdown in March and April 2020. More than half of the 5,000 Canadian volunteers in one study also reported sleep disruptions during the pandemic. These changes in sleep patterns included the inability to fall asleep (insomnia), difficulty staying asleep and sleeping too much. The increase in sleep disorders during the pandemic has become so common that doctors have started calling it “COVID-somnia.” In many cases, the rise in insomnia was linked with increased levels of stress and anxiety directly associated with fear of COVID-19 itself. Other pandemic-related problems—such as financial worries, social isolation or increased family conflicts—also contributed to poor sleep.

People who have had COVID-19 often have trouble sleeping, in some cases for at least three months after getting sick. Many people who are recovering from COVID-19 have reported difficulty sleeping as one of their lingering symptoms. This is true even in people with mild illness who were not hospitalized. Some survivors fear falling asleep because they worry that something is going to happen to them overnight. Others wake up gasping for breath, possibly because the virus has altered how the brain controls breathing. Inflammation in the brain has also been suggested as a possible cause for ongoing neurological problems—including sleep disturbances—after a COVID-19 infection.

Viruses are known to affect our normal daily biological cycles called circadian rhythms. This could be another way that COVID-19 might alter normal sleep patterns. Another possible connection is melatonin, a hormone the brain releases at night to help us maintain a normal sleep-wake cycle. Early in the pandemic, scientists thought melatonin might be able to prevent COVID-19 because it had been found to decrease the likelihood of a positive COVID-19 test by almost 30%. We don’t know yet how melatonin might protect against COVID-19, but its antioxidant and anti-inflammatory properties could be beneficial during a viral infection. Even if melatonin doesn’t prevent infection, its role of regulating sleep-wake cycles might help reset circadian rhythm problems the virus caused. This might be particularly relevant to older people, who are more susceptible to severe disease, because melatonin levels drop as we age.

COVID-19 clearly interferes with our sleep in a number of different ways, and we are only beginning to understand these long-lasting effects. But one thing we can be sure about is that whether you are recovering from COVID-19 or just trying to stay healthy during the pandemic, getting a good night’s sleep has never been more important.