The new frontier: Clinical consequences of long COVID

Abstract

Background: After infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a variety of clinical outcomes have been known to occur, ranging from asymptomatic infection or with only minor symptoms to a devastating form of the disease that requires intensive care hospitalization and is often associated with death. In April 2020, shortly after the beginning of the coronavirus disease 2019 (COVID-19) pandemic, another form of the disease began appearing in patients with COVID-19 with anecdotal reports that suggested that previously healthy individuals were now experiencing lingering symptoms and were not fully recovering from an initial infection with SARS-CoV-2, and the condition came to be known as long COVID (also known as postacute sequelae of SARS-CoV-2 infection or long-haul COVID) a term used to describe the long-lasting symptoms and complications that some people experience after recovering from an initial COVID-19 infection. These symptoms can persist for weeks or even months after the acute phase of the illness has resolved. Objective: The purpose of the present report is to review the many factors associated with long COVID and the clinical consequences of the condition, with a focus on those aspects that have relevance to the pulmonologist. Results: The exact cause of long COVID is not fully understood but is believed to be related to the complex interplay between the SARS-CoV-2 virus and the human immune system. There are several possible mechanisms that could contribute to the development of long COVID symptoms, including ongoing inflammation, immune dysfunction, and damage to various organs and tissues, including the respiratory system, the primary portal of entry of the virus. Conclusion: Long COVID is a substantial challenge for patients and health-care providers, because it can have a profound impact on a person's quality of life and ability to work or carry out daily activities. There are currently no practical diagnostic tests or specific treatment for the condition, but the pulmonologist may play an important role in the management of patients with Long COVID, particularly for individuals who are experiencing ongoing respiratory symptoms or pulmonary complications after a COVID-19 infection, e.g., fibrosis, which has been recently recognized as an emerging problem.