The “coronavirus disease 2019 (COVID-19)” outbreak was first
reported in December 2019 (China). Since then, this disease has rapidly
spread across the globe and in March 2020 the World Health Organization
(WHO) declared the COVID-19 pandemic.1 Since the
outbreak was first announced, our journal has extensively focused on the
clinical features, outcomes, diagnosis, immunology, and pathogenesis of
COVID-19 and its infectious agent severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2). We published our first COVID-19 article on
19 February, focusing for the first time on the clinical characteristics
of 140 cases of human-to-human coronavirus transmission without any
links to the Huanan Wet Market.2 Hypertension and
diabetes were mentioned as risk factors and there was no increased
prevalence in allergic patients. This early study reported that the main
symptoms at hospital admission were fever (91.7%), cough (75.0%),
fatigue (75.0%), gastrointestinal symptoms (39.6%), and dyspnea
(36.7%). Lymphopenia and eosinopenia were also reported as important
signs and biomarkers for monitoring and severity of the
patients.2 The prevalent eosinopenia in COVID-19
patients and the possible anti-viral role of eosinophils were further
discussed in several following publications inAllergy .3,4 Our second COVID-19 paper brought
attention to the wide range of clinical manifestations of this disease,
from asymptomatic cases to patients with mild and severe symptoms, with
or without pneumonia as well as with only diarrhea.5Patients with common allergic diseases did not develop distinct symptoms
and severe courses. Cases with pre-existing chronic obstructive
pulmonary disease or complicated with a secondary bacterial pneumonia
were severe. Another article, timely appearing in our journal, alerted
the scientific community that even in experienced hands there was a
14.1% false negative polymerase chain reaction (PCR) diagnosis in
COVID-19 cases and were later diagnosed positive after repeated
tests.6 A pediatric article was also published
extensively analyzing 182 cases and it was reported that children with
COVID-19 showed a mild clinical course.7 Patients with
pneumonia had a higher proportion of fever and cough and increased
inflammatory biomarkers compared to those without pneumonia. There were
43 allergic patients in this series and there was no significant
difference between allergic and non-allergic COVID-19 children in
disease incidence, clinical features, laboratory, and immunological
findings. Allergy was not a risk factor for disease and severity of
SARS-CoV-2 infection and did not significantly influence the disease
course of COVID-19 in children.7
The immunology of COVID-19 was extensively reviewed in two articles from
leading experts with a comprehensive discussion of the tip of the
iceberg in COVID-19 epidemiology, anti-viral response, antibody response
to SARS-CoV-2, acute phase reactants, cytokine storm, and pathogenesis
of tissue injury and severity. 8,9
Two studies timely reported the role of possible trained immunity in
countries with a Bacillus Calmette-Guérin (BCG) vaccination programme
and a relatively low COVID-19 prevalence and mortality
rate.10,11 In an extensive RNA sequencing analyses of
SARS-CoV-2 receptor and their molecular partners revealed that ACE2 and
TMPRSS2 were coexpressed at the epithelial sites of the lung and skin,
whereas CD147 (BSG), cyclophilins (PPIA and PPIB), CD26 (DPP4) and
related molecules were expressed in both, epithelium and in immune
cells.12
Allergists, respiratory physicians, pediatricians, and other health care
providers treating patients with allergic diseases are frequently in
contact with patients potentially infected with SARS-CoV-2. Practical
considerations and recommendations given by experts in the field of
allergic diseases can provide useful recommendations for clinical daily
work. Since the beginning of this current pandemic, our journal has
disseminated clinical reports, 2,3,5,6,13 statements
on the urgent need for accuracy in designing and reporting clinical
trials in COVID-19,14 preventive
measures,10,11,15 and Position Statements elaborated
by experts in the field in close collaboration with the European Academy
of Allergy and Clinical Immunology (EAACI) and its task force
“Allergy and Its Impact on Asthma
(ARIA) ”.16-28 (keynote information in table 1). A
compendium answering 150 frequently encountered questions regarding
COVID-19 and allergic diseases has been recently published by experts in
their respective area.29 In addition, readers can put
further questions regarding this “living ” compendium
electronically to the authors and their answers will be available
through a new category in the journal’s webpage.30Besides, EAACI in collaboration with ARIA, has provided recommendations
on operational plans and practical procedures for ensuring optimal
standards in the daily clinical care of patients with allergic diseases,
whilst ensuring the safety of patients and healthcare
workers.23
Table 1: Examples of recently published recommendations, statements and
Position Papers of the EAACI