CCL2 and susceptibility to pneumonia measurement: fever, dry cough, fatigue, shortness of breath, muscle ache, confusion, headache, sore throat, rhinorrhea, chest pain, diarrhea, nausea, vomiting, chills, sputum production, haemoptysis, dyspnea, bilateral pneumonia anorexia, chest pain, leucopenia, lymphopenia, olfactory and taste disorders, higher levels of plasma cytokines (IL2, IL7, IL10, GSCF, IP10, MCP1, MIP1A, and TNFα) (ICU patients)