More than half a million Americans have died from COVID-19. Thousands more suffered from financial losses compounded by businesses, schools and daycares shutting down. The fallout of COVID-19 is real—and for a subset of Americans, it's a textbook trigger for post-traumatic stress disorder, or PTSD.

Dr. Itai Danovitch, a psychiatrist at Cedars-Sinai, says over 90% of people experience a major traumatic event at some point during their lifetime. Even with similar experiences, some people walk away largely unscathed while others may carry emotional scars that color their everyday lives for decades.

PTSD is a psychological condition that occurs on the heels of a traumatic event, ranging from a natural disaster to the death of a loved one to a global pandemic. Perhaps best known as a disorder that strikes war veterans, PTSD can happen to anyone, regardless of their age, ethnicity or gender.

"It's normal to have a fear response to something traumatic. Typically, that fear response diminishes over time. The intensity of the memory fades and we move on with our lives," Dr. Danovitch says. "In PTSD, the memories don't fade. They feel very present and can intensify over time and they can influence our thoughts, emotions and our ability to function."

PTSD can arise within days, weeks or even years of a traumatic event, such as a rape, terrorist act or serious accident. Hallmark symptoms include:

• Intrusive memories. You relive the event through flashbacks, nightmares and involuntary memories. You may even have difficulty sleeping because of intrusive thoughts or dreams.
• Avoidance behaviors. You avoid people, places, activities and situations that could trigger a distressing memory. "Avoidance is a protective strategy, but it protects us at a cost," Dr. Danovitch says. You may resist talking about what happened and begin to feel detached or isolated from other people.
• Hyperarousal and reactivity. You might startle easily and have a strong reaction to ordinary sensory experiences, such as loud noises or a light touch. A combat veteran who has PTSD, for example, may hear a staccato sound and immediately react as if it's gunfire.
• Mood disturbances. You may suffer from distorted thoughts and feelings of sadness, guilt or fear. It's not uncommon for people with PTSD to have angry outbursts, behave recklessly or in a self-destructive manner, or be highly irritable.

To be diagnosed with PTSD, these symptoms must persist for at least one month and interfere with your daily functions, relationships and quality of life. In some cases, PTSD symptoms persist for months and sometimes years, and PTSD may coexist with other psychological problems, such as depression, anxiety and substance abuse.

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It's important to note that not everyone who experiences a terrifying or life-threatening event will go on to develop PTSD. In fact, most people weather tremendous trauma without ongoing distress and suffering. Whether or not you develop persistent symptoms is related, in part, to how your body and mind process the trauma you've experienced.

"There are a wide range of traumas, from accidents and assaults, to loss and illness," Dr. Danovitch says. "While there is a relationship between trauma severity and PTSD, any one of these events be a trigger. What these traumatic experiences share is a sense of terror. We feel helpless and out of control."

One known trigger: COVID-19. Up to one-third of people who experience the sensation of not being able to breathe, as in severe cases of COVID-19, develop clinical PTSD after those experiences. "Studies show that the experience of being hospitalized—being confused and frightened and feeling like you're drowning—is traumatizing," Dr. Danovitch says.

Other factors that can lead to the development of PTSD include:

• Having a history of mental illness or substance use disorder
• Living through dangerous events
• Getting physically or emotionally hurt
• Observing another person suffering
• Childhood trauma, abuse or neglect
• Feeling unsafe in your environment
• Limited social support

But there are protective factors, too, such as:

• Having a strong support network
• Having solid coping strategies
• Being able to respond effectively in the face of fear
• Seeking support from other people
• Establishing safety

Read: Coping With Trauma in the Wake of COVID-19

The main treatments for PTSD are medications, psychotherapy or a combination of both strategies. But every person, and every trauma, is unique—what works for one person may not work for another. In every case, PTSD should be addressed by a mental health professional.

In terms of medication, the mainstay treatments are selective serotonin reuptake inhibitors (SSRIs) and antidepressants, both of which can improve mood and control symptoms, such as sadness, worry and anger. If you're suffering from sleep disturbances, your doctor may prescribe medications to help you sleep. There's also emerging evidence to suggest that mind-altering medications such as ketamine and MDMA-assisted therapy can help patients with PTSD.

Read: Good Sleep in Times of Stress

"These are still experimental treatments, and they are not without risk. Preliminary studies have shown that in a therapy setting with a trained guide, this form of treatment may help some patients have transcendent experiences that facilitate recovery," Dr. Danovitch says.

With standard psychotherapy for PTSD, there are two key approaches:

• Exposure therapy: The idea behind exposure therapy is to desensitize your fear response by gradually exposing yourself to the trauma in a safe, controlled way. You might imagine the traumatic event, write about it or visit the place where the event happened. Over time, and with training, you learn to withstand the response you have to the traumatic trigger.
• Cognitive restructuring: With cognitive restructuring, you learn to evaluate your thought patterns and emotional responses. For example, you may feel guilt or shame about something that isn't your fault. "The meaning we put on things, the stories we tell ourselves and the coping skills we use can have a huge effect on whether we feel empowered or victimized," Dr. Danovitch says.

While there's still a stigma around mental health issues, the traumatic pandemic we're beginning to emerge from has shined a light on the importance of mental and emotional health. "PTSD is treatable," Dr. Danovitch says. "The goal is to help people access treatment."

Healthcare professionals have been disproportionately traumatized during the COVID-19 pandemic. Between rising death tolls, ineffective treatments and even inadequate personal protective equipment, healthcare professionals have been in survival mode for more than 15 months.

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