[…] that produces greenish or rust-colored mucus These are symptoms of viral pneumonia: > Initial flulike symptoms: fever, headache, muscle aches and dry cough > Worsening of
[weather.com]
You may also experience pain in your ribs from frequent, hard coughing. Coughing – Both the flu and pneumonia cause coughing. A flu cough is likely to be a dry cough.
[augustahealth.com]
Although her clinical and laboratory findings were consistent with the diagnosis of H1N1 pneumonia, e.g., fever, sore throat, dry cough, arthralgias, myalgias, thrombocytopenia
[ncbi.nlm.nih.gov]