It started mildly congested, with the occasional sneeze.

However, a lack of appetite, shortness of breath, chest aches, and insomnia soon followed. The week of sleepless nights was particularly trying, leaving Isaiah Smith, 26, tired as COVID-19 symptoms came in waves.

As his heart beat violently, the former senior airman from Merrillville, Indiana, finally dialed for an ambulance at 2 am to get to the hospital as soon as possible.

Patients with extended COVID, also called long-haul COVID or post-COVID-19 syndrome, might experience a wide range of symptoms. Symptoms can range from trouble breathing to muscle aches to more serious diseases such as mental health disorders and suicidal thoughts, and they can linger for weeks, months, or even years.

According to Dr. Elizabeth Brill, a VA COVID expert, who spoke to reporters at a VA press briefing on April 25, "their underlying medical conditions, their age, and their risk factors... might skew them from the general population" due to their long COVID.

Veterans are still determining whether toxic exposure and combat will add long COVID to the list of conditions exacerbated by service. However, VA research shows those with long COVID are at high risk of developing other serious illnesses. Following that, they are treated through a patchwork of 17 VA extended COVID care programs that offer diverse treatment options comparable to non-military medical networks.

These VA programs, some online and some in-person, differ partly because medical researchers are still trying to solve the riddle of long COVID.