ABSTRACT
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), is a global health threat with the potential to cause severe disease manifestations in the lungs. Although COVID-19 has been extensively characterized clinically, the factors distinguishing SARS-CoV-2 from other respiratory viruses are unknown. Here, we compared the clinical, histopathological, and immunological characteristics of patients with COVID-19 and pandemic influenza A(H1N1). We observed a higher frequency of respiratory symptoms, increased tissue injury markers, and a histological pattern of alveolar pneumonia in pandemic influenza A(H1N1) patients. Conversely, dry cough, gastrointestinal symptoms and interstitial lung pathology were observed in COVID-19 cases. Pandemic influenza A(H1N1) was characterized by higher levels of IL-1RA, TNF-α, CCL3, G-CSF, APRIL, sTNF-R1, sTNF-R2, sCD30, and sCD163. Meanwhile, COVID-19 displayed an immune profile distinguished by increased Th1 (IL-12, IFN-γ) and Th2 (IL-4, IL-5, IL-10, IL-13) cytokine levels, along with IL-1ß, IL-6, CCL11, VEGF, TWEAK, TSLP, MMP-1, and MMP-3. Our data suggest that SARS-CoV-2 induces a dysbalanced polyfunctional inflammatory response that is different from the immune response against pandemic influenza A(H1N1). Furthermore, we demonstrated the diagnostic potential of some clinical and immune factors to differentiate both diseases. These findings might be relevant for the ongoing and future influenza seasons in the Northern Hemisphere, which are historically unique due to their convergence with the COVID-19 pandemic.
Subject(s)
COVID-19 , Cytokines , Influenza A Virus, H1N1 Subtype , Influenza, Human , Matrix Metalloproteinase 1 , Matrix Metalloproteinase 3 , Receptors, Immunologic , Adult , Aged , COVID-19/blood , COVID-19/epidemiology , COVID-19/immunology , Cytokines/blood , Cytokines/immunology , Female , Humans , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H1N1 Subtype/metabolism , Influenza, Human/blood , Influenza, Human/epidemiology , Influenza, Human/immunology , Male , Matrix Metalloproteinase 1/blood , Matrix Metalloproteinase 1/immunology , Matrix Metalloproteinase 3/blood , Matrix Metalloproteinase 3/immunology , Middle Aged , Prospective Studies , Receptors, Immunologic/blood , Receptors, Immunologic/immunology , Th1 Cells/immunology , Th2 Cells/immunologyABSTRACT
We review important aspects of the pandemic influenza A (H1N1) at the time of declaring the end of the contingency in Mexico. The pre-established surveillance system had to be modified during the course of the epidemic. From the first epidemic weeks, viral monitoring recorded the displacement of other pathogens by the pandemic virus. Patients at high risk for complications were identified together with the need for early treatment with antiviral drugs, thus avoiding the saturation of intensive care beds. The difficulties of surging services for seriously ill patients are described. Preventive measures such as the use of masks and hand hygiene are reviewed, as well as the vaccination drive and the difficulties for its application in health personnel. The review concludes with the need to learn the teachings of the pandemic, describing the necessary elements to prepare against the next one.
