The long-term effects on mental health from COVID-19 has many psychologists concerned. They say, as the U.S. strives to return to some form of physical normalcy, many Americans will suffer mental health issues long after the pandemic subsides.

"I'm very concerned about the effects being long-term," said Dr. Luana Marques, associate professor of psychiatry at Harvard Medical School and the director of Community Psychiatry PRIDE at Massachusetts General Hospital, according to NBC News. "Given that —consistently, globally — you've seen the levels of depression and anxiety high since last March. That tells me that we're going to see an increasing prevalence of mental health problems globally."

The number of Americans seeking mental health services surged during the COVID-19 pandemic. With anxiety and depression on the rise, mental health experts across the nation have been inundated with patients desperately needing help but unable to secure appointments.

A December Gallup poll found America's mental health had deteriorated to the worst point in two decades. Only 34% of U.S. adults said their mental health was excellent, down from 43% the previous year.

"Never at any time in my practice have I had a five-person waiting list," said psychotherapist Brooke Huminski, of Providence, R.I., according to The New York Times.

A poll conducted last November by the American Psychological Association found 74% of the psychologists surveyed said, since the COVID-19 pandemic, they were seeing more patients with anxiety disorders, and 60% more with depressive disorders. Overall, the experts saw a 30% increase in patient load.

While healthcare professionals have largely focused on protecting our physical wellbeing over the past year, now that vaccines have helped control the spread of COVID-19, experts say the shift must be to understand and treat the mental health issues of Americans.

Last April, Benjamin F. Miller, a clinical psychologist and adjunct professor in the Department of Psychiatry and Behavioral Sciences in the Stanford School of Medicine, predicted the mental health issue in America would become "epidemic," according to USA Today.

"It's hard to imagine a scenario dealing with something as unknown as coronavirus and not be a bit stressed; however, at this moment the multitude of stressors may be like pouring gasoline on an existing wildfire," he said.

Miller added, according to surveys, a whopping 71% of Americans are worried social isolation, an important part of fighting the virus, will have a negative impact on their mental health.

Catherine Ettman, a doctoral student at Brown University School of Public Health, has been researching the mental health effects of the pandemic since March of 2020.

"Our research has shown an increase in depressive symptoms, anxiety symptoms, and post-traumatic stress symptoms," she said, according to NBC News. She and her team found  depression rates more than tripled since the pandemic began.

Experts say there are a number of contributory factors that have negatively affected our nation's mental health. These include fear of getting infected by COVID-19, the burden of social isolation, and worries about jobs and finances.

Marques said she is concerned, if healthcare experts do not address the pervasive mental health crisis, the problems are going to be long-lasting, according to NBC News. Marques and others add, the long-term effects will be worse for those hardest hit by the pandemic, including people of color.

Ettman added, in order to address mental health issues, people have to feel stable, and that could mean helping them financially, so they are less likely to be depressed and anxious.