General term for any of a number of cold or flu maladies that you get from riding San Francisco's crowded and poorly ventilated Muni Trains.
"Ugh... I think I'm coming down with Muni Malaria. I probably got it from the tiny Asian lady with no sense of personal-space who kept coughing on me on my commute yesterday morning. The garlic bagel she had for breakfast wasn't very appetizing while being sneezed into my face."