deep in my chest and not let go

[NewAmerica]

The expression "deep in my chest and not let go" makes me quite puzzled.

What is "deep in my chest"? Flu?

Thanks in advance

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Sue Decottis, a physician in internal medicine at New York University Langone Medical Center who also has a private practice, says herbals can have some value and she will, on occasion, recommend them to her patients. She hasn’t prescribed Pei Pa Koa. “There’s also the placebo effect with anything like that, but there’s no real money behind it to do big studies,” Dr. Decottis said.
“I got a bottle of it in the height of my flu which seemed to hang about this year for two months deep in my chest and not let go,” said Matthew Modine, the actor currently starring in Netflix’s “Stranger Things.” <................>

-The Wall Street Journal

Source

 

[dojibear]

Yes, he had a flu "deep in his chest". The flu stayed for two months and "would not let go" (would not go away).

 

[NewAmerica]

Thank you.

Did she say or imply any effect of the bottle of the "medicine" (Pei Pa Koa), for example, implying that the "medicine" works?