You may have heard it referred to as post-COVID-19, long-hauler syndrome or long COVID. The official title of the condition is Post-Acute Sequelae of SARS-CoV-2 infection, or PASC. SARS-CoV-2 is the virus that causes COVID-19.
As we begin to consider the new landscape wrought by the COVID-19 pandemic, clearly one of the greatest challenges is going to be managing the long-term effects of SARS-CoV-2 that occur in a significant proportion of those who recover from the acute phase of the infection.
By some estimates, long COVID affects 30% to 70% of those who have been diagnosed with COVID-19. Long COVID has yet to be completely defined, given the relatively recent emergence of COVID-19. Generally, it applies to the persistence of one or more symptoms of coronavirus infection or the emergence of new symptoms four weeks or more after the initial phase of illness.
Long COVID may affect anyone who has been infected regardless of age, previous health status or degree of severity of the symptoms during initial infection. It can even affect those who experienced an asymptomatic infection.
A study published this week in the journal Cell identified four potential factors that may influence the development of long COVID. The first is the amount of virus present at the beginning of infection, also known as viral load. People with higher initial viral load appear more susceptible. The second is the presence of so-called autoantibodies, which are antibodies that can damage the body’s tissues.
A third factor is the reactivation of Epstein-Barr virus, a common virus which lies dormant in many people after initial infection during childhood or adolescence. The final factor that appears to increase long-COVID risk is having Type 2 diabetes, a chronic condition that affects tens of millions of Americans.
Long COVID symptoms are myriad and can involve the nervous system, gastrointestinal system, cardiopulmonary system and musculoskeletal system, among others. Symptoms can include long-term loss of taste and/or smell, tiredness or fatigue, breathing difficulty or cough, sleep problems, dizziness and heart palpitations – just to name a few (a more exhaustive list can be found on the Centers for Disease Control and Prevention’s website).
The best prevention for long COVID is vaccination to reduce the risk of developing SARS-CoV-2 infection in the first place. While studies are ongoing, there is promising evidence that vaccines also reduce the risk of developing long COVID even among people who develop a breakthrough infection after becoming fully vaccinated.
Currently, treatment for long COVID is geared toward supportive therapies, depending on symptoms. Some examples include physical therapy, cardiopulmonary rehabilitation, memory exercises, olfactory training (to assist with lost sense of smell).
There is much yet to be learned about long COVID, and many studies are underway to better understand this condition and how to treat it. Meanwhile, the best defense against long COVID is to stay up to date with vaccination.
Dr. Matthew A. Clark, a board-certified physician in internal medicine and pediatrics, works for the Indian Health Service.
