ABSTRACT
SARS-CoV-2, the agent responsible for COVID-19, has wreaked havoc around the globe. Hundreds of millions of individuals have been infected and well over six million have died from COVID-19. Many COVID-19 survivors have ongoing physical and psychiatric morbidity, which will remain for the rest of their lives. Early in the pandemic, it became apparent that older individuals and those with comorbidities including obesity, diabetes mellitus, coronary artery disease, hypertension, and renal and pulmonary disease were at increased risk of adverse outcomes. It is also clear that some immunodeficient patients, such as those with innate or T cell-immune defects, are at greater risk from COVID-19. Selective IgA deficiency (sIgAD) is generally regarded as a mild disorder in which most patients are asymptomatic because of redundancy in protective immune mechanisms. Recent data indicate that patients with sIgAD may be at high risk of severe COVID-19. SARS-CoV-2 gains entry primarily through the upper respiratory tract mucosa, where IgA has a critical protective role. This may underlie the vulnerability of sIgAD patients to adverse outcomes from COVID-19. This perspective highlights the need for ongoing research into mucosal immunity to improve COVID-19 treatments for patients with sIgAD.
ABSTRACT
SARS-CoV-2, the agent responsible for COVID-19, has caused havoc around the globe. Hundreds of millions of individuals have been infected and well over six million have died from COVID-19. Many COVID-19 survivors have ongoing physical and psychiatric morbidity, which will remain for the rest of their lives. Early in the pandemic, it became apparent older individuals and those with comorbidities including obesity, diabetes mellitus, coronary artery disease, hypertension, renal and pulmonary disease were at increased risk of adverse outcomes. It is also clear that some immunodeficient patients, such as those with innate or T cell immune defects are at greater risk from COVID-19. Selective IgA deficiency (sIgAD) is generally regarded as a mild disorder, where the majority of patients are asymptomatic because of redundancy in protective immune mechanisms. Recent data indicates patients with sIgAD may be at high risk of severe COVID-19. SARS-CoV-2 gains entry primarily through the upper respiratory tract mucosa, where IgA plays a critical protective role. This may underlie the vulnerability of sIgAD patients for adverse outcomes from COVID-19. This perspective highlights the need for ongoing research into mucosal immunity and improving COVID-19 treatments for patients with sIgAD.
ABSTRACT
COVID-19 has had a disastrous impact on the world. Apart from at least 6 million deaths, countless COVID-19 survivors are suffering long-term physical and psychiatric morbidity. Hundreds of millions have been plunged into poverty caused by economic misery, particularly in developing nations. Early in the pandemic, it became apparent certain groups of individuals such as the elderly and those with comorbidities were more likely to suffer severe disease. In addition, patients with some forms of immunodeficiency, including those with T-cell and innate immune defects, were at risk of poor outcomes. Patients with immunodeficiencies are also disadvantaged as they may not respond optimally to COVID-19 vaccines and often have pre-existing lung damage. SARS-CoV-2 Omicron (B.1.529) and its subvariants (BA.1, BA.2, etc) have emerged recently and are dominating COVID-19 infections globally. Omicron is associated with a reduced risk of hospitalization and appears to have a lower case fatality rate compared with previous SARS-CoV-2 variants. Omicron has offered hope the pandemic may finally be coming to an end, particularly for vaccinated, healthy individuals. The situation is less clear for individuals with vulnerabilities, particularly immunodeficient patients. This perspective offers insight into potential implications of the SARS-CoV-2 Omicron variant for patients with immunodeficiencies.