SARS-CoV-2 infection can present a variety of disease presentations, from asymptomatic to mild-moderate COVID-19 symptoms as is the case for most previously healthy individuals, to life-threatening disease or even persistent debilitating symptoms in some cases. In symptomatic adults, the disease typically presents after 2–14 days of incubation as a respiratory illness. Asymptomatic infection occurs in a significant fraction of individuals, and as many as half of all transmission events were reported to occur from pre-symptomatic and asymptomatic individuals.
One of the most important determinants of disease severity is age, as individuals over 65 years have the greatest risk of requiring intensive care. Contrary to what is observed for other respiratory viral infections, young children seem to be less severely affected. Nevertheless, a post-infectious hyperinflammatory disease (also known as Multisystem inflammatory syndrome in children or MIS-C) has been described as a rare outcome after SARS-CoV-2 infection in children and young adults. Its pathogenesis is unknown, but its onset has a delay of 2–6 weeks from the initial SARS-CoV-2 infection, which hints at a role for adaptive immune responses and or specific autoantibodies.
Independently of severity, acute infection is not the only outcome of COVID-19 as reports of long-lasting symptoms are mounting. In contrast to the severe acute COVID-19, the condition referred to as ‘long COVID’ is more predominant in women than men. Even individuals with mild COVID-19 symptoms can suffer from long COVID for many months after they cleared the initial infection. People with long COVID often report persistent fatigue, intestinal disturbances, and skin manifestations. Long COVID is analogous to other post-infectious syndromes for example those associated with outbreaks of chikungunya and Ebola. These symptoms are often linked to infection triggering a strong immune activation, a dysregulated autonomic nervous system, and perturbed immune parameters. The large number of individuals currently suffering from long COVID provides a unique opportunity to study the pathogenesis of these general post-infectious syndromes.
In this collection we aim at addressing the role of imbalanced immune responses in the overall severity of acute COVID-19, post-infectious hyperinflammatory disease, and long COVID. This Research Topic aims at increasing the understanding of the immunological determinants of COVID-19 disease presentation and severity. The goal is to relate this to known immune-system differences that manifest with age, between genders, and other factors associated with the potential different disease presentations and severity. We welcome Original Research, Methods, Review, Mini Review, Hypothesis and Theory, Perspective, Clinical Trial and Case Report articles covering, but not limited to, the following subtopics
- Role of immune senescence and previous exposure to seasonal coronavirus on disease severity
- Components of the immune system responsible for the protection of children and asymptomatic carriers from COVID-19
- Components involved in post-infectious hyperinflammatory disease
- The immune triggers of long COVID
Topic Editor Mariana Bego is the founder of Genquest DNA, LLC. The other Topic Editors declare no competing interests.
SARS-CoV-2 infection can present a variety of disease presentations, from asymptomatic to mild-moderate COVID-19 symptoms as is the case for most previously healthy individuals, to life-threatening disease or even persistent debilitating symptoms in some cases. In symptomatic adults, the disease typically presents after 2–14 days of incubation as a respiratory illness. Asymptomatic infection occurs in a significant fraction of individuals, and as many as half of all transmission events were reported to occur from pre-symptomatic and asymptomatic individuals.
One of the most important determinants of disease severity is age, as individuals over 65 years have the greatest risk of requiring intensive care. Contrary to what is observed for other respiratory viral infections, young children seem to be less severely affected. Nevertheless, a post-infectious hyperinflammatory disease (also known as Multisystem inflammatory syndrome in children or MIS-C) has been described as a rare outcome after SARS-CoV-2 infection in children and young adults. Its pathogenesis is unknown, but its onset has a delay of 2–6 weeks from the initial SARS-CoV-2 infection, which hints at a role for adaptive immune responses and or specific autoantibodies.
Independently of severity, acute infection is not the only outcome of COVID-19 as reports of long-lasting symptoms are mounting. In contrast to the severe acute COVID-19, the condition referred to as ‘long COVID’ is more predominant in women than men. Even individuals with mild COVID-19 symptoms can suffer from long COVID for many months after they cleared the initial infection. People with long COVID often report persistent fatigue, intestinal disturbances, and skin manifestations. Long COVID is analogous to other post-infectious syndromes for example those associated with outbreaks of chikungunya and Ebola. These symptoms are often linked to infection triggering a strong immune activation, a dysregulated autonomic nervous system, and perturbed immune parameters. The large number of individuals currently suffering from long COVID provides a unique opportunity to study the pathogenesis of these general post-infectious syndromes.
In this collection we aim at addressing the role of imbalanced immune responses in the overall severity of acute COVID-19, post-infectious hyperinflammatory disease, and long COVID. This Research Topic aims at increasing the understanding of the immunological determinants of COVID-19 disease presentation and severity. The goal is to relate this to known immune-system differences that manifest with age, between genders, and other factors associated with the potential different disease presentations and severity. We welcome Original Research, Methods, Review, Mini Review, Hypothesis and Theory, Perspective, Clinical Trial and Case Report articles covering, but not limited to, the following subtopics
- Role of immune senescence and previous exposure to seasonal coronavirus on disease severity
- Components of the immune system responsible for the protection of children and asymptomatic carriers from COVID-19
- Components involved in post-infectious hyperinflammatory disease
- The immune triggers of long COVID
Topic Editor Mariana Bego is the founder of Genquest DNA, LLC. The other Topic Editors declare no competing interests.
