A fever, sore throat and cough can make the diagnosis seem obvious. But respiratory infections do not always follow neat patterns. H1N1 influenza and COVID-19 can begin with remarkably similar symptoms, yet they are caused by different viruses and may require different treatment decisions. “The key takeaway is simple: when respiratory symptoms look similar, testing can provide the clarity needed for the right care at the right time,” said Dr Niranjan Patil, Associate Vice President of Metropolis Healthcare Limited, Mumbai.