FROM OUR EXPERIENCE IN HOST GENOMICS AND TRANSCRIPTOMICS IN INFECTIOUS DISEASES, THE HYPOTHESIS ARISES THAT THE GENETICS OF THE HUMAN HOST MAY CONTRIBUTE TO EXPLAIN THE DIFFERENTIAL BEHAVIOR OF SARS-COV-2 IN DIFFERENT SUBJECTS AND AGE GROUPS. THROUGH THE "OMIC" STUDY OF DNA, RNA AND SERUM OF PEDIATRIC AND ADULT PATIENTS WITH DIFFERENT SEVERITY, IT IS INTENDED TO DETECT SOLUBLE IMMUNOLOGICAL BIOMARKERS THAT CHARACTERIZE THE IMMUNE RESPONSE TO SARS-COV-2, AND TO IDENTIFY GENETIC MARKERS OF SUSCEPTIBILITY AND PROGNOSIS OF COVID19 THAT ALLOW REVEAL NEW THERAPEUTIC TARGETS, ESTABLISH DIAGNOSIS-PROGNOSIS BASED ON SPECIFIC TRANSCRIPTOMIC FINGERPRINTS AND PERSONALIZED PRESCRIPTION OF THERAPEUTIC OR PREVENTIVE MEASURES.