Clinical and Immunological Characterisation of COVID-19 in Children, Adolescents and Adults

In 2019 the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified as the pathogen causing the Coronavirus Disease 2019 (COVID-19) pandemic. Many retrospective studies have been conducted regarding clinical signs and symptoms and clinical course of the disease. In most cases the infection causes only light symptoms of the upper respiratory tract. The infection can also be asymptomatic. However, in some the disease can cause a severe infection of the lower respiratory tract leading to acute respiratory syndrome (ARDS) which can be fatal. Especially elderly people suffer from severe disease whereas children are less compromised.

In this prospective, monocentric study the investigators include patients of all ages with COVID-19 and also a control group of all ages with respiratory tract infections other than COVID-19. Initial presentation, clinical course, outcome and the therapy used will be recorded. Standard diagnostic procedures (vital signs, results of blood samples, blood gas analysis, x ray, ct scan) will also be recorded. To further characterise the study population naso- and oropharyngeal swabs will be checked for viral and bacterial coinfections. The SARS-CoV-2 viral load will be estimated. To characterise the immunological response IgM- and IgG-antibodies for SARS-CoV-2 will be measured. Moreover lymphocyte typing, cytokine and chemokine analysis will be conducted. The investigators will also include an analysis of the proteome in serum and urine. To characterise the virus-host-interaction HLA analysis of the patients will be conducted. In the case of a medically indicated bronchoscopy bronchoalveolar lavage will be analysed in regards of viral load, coinfections, lymphocyte typing and cytokines / chemokines. In case of a medically indicated lung biopsy or in a post mortem lung biopsy a histological analysis will be made.

In general, samples will be analysed at the initial presentation and after two weeks. Further analysis will be conducted depending on special events like clinical deterioration. Long-term follow up will be ensured by telephone visits.