It's become clear to a growing number of medical researchers that COVID-19 is not simply a respiratory ailment.

While it often initially presents that way—as a cough or, in some cases, as breathing problems—that's just one aspect.

COVID-19 is actually a "highly heterogeneous and complex medical disorder", according to a paper published last year in the International Journal of Immunopathology and Pharmacology.

Post COVID-19 condition, a.k.a. Long COVID, is the term used to describe those who demonstrate symptoms or effects of their infection at least two months later.

Today (June 9) is National Long COVID Awareness Day. It's a creation of Public Health Agency of Canada researchers who want to educate the public about this issue.

It's being marked by an online town hall meeting, which begins at 9 a.m. Pacific time today.

This week, we've posted two articles on Straight.com highlighting new research into Long COVID.

On June 8, we reported on a preprint of a review of 21 studies looking at this illness in children and adolescents. It found that about 25 percent of these kids and teenagers develop Long COVID after being infected. The most prevalent clinical manifestations were mood disorders, fatigue, and sleep disorders.

The previous day, we posted a Twitter thread by Oxford University professor of primary care, Dr. Trisha Greenhalgh, who's part of a team conducting a massive study of Long COVID in the U.K.

"In long covid, the body reacts in a counterproductive way to the virus," Greenhalgh wrote in the thread. "Mechanisms include chronic inflammation, thrombosis ('micro clots') and endothelial damage. This impacts various organs—e,g, autonomic nervous system."

Earlier this year, the journal Nature reported on a huge study that showed "a long-term, substantial rise in risk of cardiovascular disease, including heart attack and stroke, after a SARS CoV-2 infection".

“It doesn’t matter if you are young or old, it doesn’t matter if you smoked, or you didn’t,” study co-author Ziyad Al-Aly at Washington University in St. Louis, Missouri is quoted as saying in Nature. “The risk was there.”