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Depression
5 Ways to Beat Post-Viral Blues
These straightforward strategies can help you bounce back after sickness.
Posted March 1, 2025 Reviewed by Margaret Foley
Key points
- If you feel down after viral infection, it's not your fault: Immune molecules can dampen your mood.
- Viral infections impair sleep and trigger the brain's stress response, leading to depressive symptoms.
- To recover, give yourself a break, rest, sleep, nap, eat a healthy diet, and gradually increase activity.
Whenever I recover from being sick, I notice a lag—sometimes lasting days—between feeling physically better and fully regaining both my energy and my mood. Although I’ve studied the brain-immune connection, when I’m down in the dumps after a viral illness, I nonetheless have to remind myself that it's not my fault.
It’s the fault of those immune molecules—cytokines and interleukins—that helped fight the infection. They're still floating around in my bloodstream, affecting my brain’s mood pathways, making everything seem dark and bleak. This awareness doesn’t necessarily get me out of my funk, but it helps motivate me to listen to my body and give it that much more time and a chance to recover.
How do you do that? Sleep is important. Sleep long and deeply at night, as long as you need to, and take naps during the day whenever you feel your energy lagging. Don’t force yourself to exercise if you don’t have the energy; do it in baby steps. Walk a little more each day until you’re fully back to your old self. Go out in nature, breathe deeply, and appreciate all around you.
Importantly, give yourself a break. Tackle a bit of whatever chores you have to do and take a rest. Then, tackle the next task and take a rest.
Healthy nutrition is also important: Eat plenty of fresh fruits and vegetables and keep your protein up.
If you’re still feeling depressed after all that, seek professional help. Again, it’s not your fault. You may need the help of antidepressant medications to staunch the downward mood cycle, especially if you’re having suicidal thoughts.
Some of the earliest studies proving that the brain and immune system communicate came out of labs studying the effects of immune molecules on the brain—in rats. Linda Watkins and Steve Maier of the University of Colorado showed that the immune molecule interleukin-1, when injected into a rat’s belly, brought on all the signs of sickness—fever, decreased movement, loss of appetite, even memory loss—and that cutting the vagus nerve (a key nerve that sends signals from the belly to the brain) prevented those effects. Watkins and Maier found that interleukin-1 latched onto receptors next to that nerve and triggered electrical impulses that went directly to the part of the brain that communicates with mood and fever centers.
At the same time, veterinarian Robert Dantzer and immunobiologist Rose-Marie Bluthé of the French National Institute of Health and Medical Research, with immunophysiologist Keith Kelley of the University of Illinois, studying rats, found that a molecule that blocked interleukin-1 prevented all the symptoms of sickness—many of which mimic depressive symptoms.
Not only can immune molecules signal the brain in these ways, but they can also seep across the barrier between the blood and the brain and affect nerve cell function and growth.
Psychiatrists Andrew Miller and Charles Raison took these studies into humans and found that patients treated for malignant melanoma with high doses of the immune molecule interferon-alpha experienced depressive symptoms and even suicidality, which could be prevented by pretreatment with antidepressants. This led to a theory that some forms of treatment-resistant major depressive disorder might be caused by inflammation. Indeed, many patients with major depressive disorder have signs of chronic inflammation with high levels of inflammatory molecules in the blood. We even found elevated levels of immune molecules in sweat that corresponded to depressive symptom scores in women with a history of major depressive disorder.
With the onset of COVID-19, the evidence that viral infection could cause mental health problems took on new importance. There are many ways that viruses like SARS-CoV-2 and others, such as herpes zoster (shingles) and herpes simplex (cold sores), can lead to depression. Many viruses cause muscle, joint, and even neuralgic pain that interferes with sleep, and poor sleep can contribute to depression.
Indeed, Miller and Raison found that sleep was severely disrupted in patients treated for hepatitis C with high doses of interferon-alpha. Patients woke up more frequently during the night and slept less deeply. They were more fatigued during the day but still had difficulty falling asleep if they attempted to nap. On top of all that, their stress hormone cortisol was elevated in the evening—a time of day when that hormone, which keeps you awake and alert, should be waning, getting you ready to wind down for sleep.
In fact, immune molecules activate the brain’s stress center, and the stress hormones that pour out make you anxious, make your heart race, and make you run to the bathroom. When the brain’s stress center is stuck like that in the "on" position, it disrupts your sleep and contributes to depressive symptoms.
During COVID-19, another factor besides all the biological ones contributed to the very high prevalence of mental health problems: the need to isolate for prolonged periods. Social isolation and loneliness are very real psychosocial factors that contribute to depression.
If following a viral infection, your depressive symptoms are severe, especially if you're experiencing severe sleep disruption and suicidal thoughts, it’s time to seek professional help. Just as with Miller and Raison’s patients with hepatitis C, a combination of antiviral and antidepressant medications, psychotherapy, and medical support may help.
So, don’t let feeling down after a viral infection keep you down. Be kind to yourself and take time to recover while doing a little at a time: Exercise, get out in nature, eat healthy, sleep, rest, and nap, and soon you should be back to your old self. But if these don’t help and you’re still feeling down, don’t wait too long: Seek professional help to get you through the worst of it.
To find a therapist, please visit the Psychology Today Therapy Directory.
References
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