What melanoma and the flu have in common

It’s ridiculous how lousy a flu bug can make you feel. I don’t think I’ve been this sick since my “lost summer” of interferon treatment in 2008, when it was merely “flu-like” symptoms I suffered through. For lack of a better explanation, I’ll blame some nasty surface I touched at one of the freeway rest stops between here and Chicago as the source of the virus. I guess I need to improve my hand-washing routine when traveling.

Perhaps someone can answer this question for me: Had I received a flu shot last fall or winter, might I have avoided this episode? I realize there are many strains of the flu virus and not all match up with the strains that a vaccine protects against. I haven’t had a serious bout of the flu for more than 25 years, hence my weak-kneed response to this one and my general reluctance to getting flu shots in the first place.

When hit with a flu virus, the body's first line of defense in fighting off infection is interferon, which binds to cells targeted by the virus. The problem with that natural reponse, as anyone who has taken interferon as adjuvant therapy for melanoma can tell you, is that it’s easy to get too much of a good thing. The worst of the symptoms I experienced from interferon infusions were a deep lethargy and depression—far worse than what I feel today.

Oddly, when you get sick with the flu, it's not always the virus itself that's to blame. In some people, it’s this interferon response that's the cause of illness. Many of the most severe cases of influenza, including deadly cases, are caused when the body produces too many of these immunity molecules. Their sudden release is dubbed a "cytokine storm" that can actually make an infection worse and sometimes requires intervention.

Beyond the interferon it’s presumably pumping out, my immune system is also scouting for the flu virus now embedded in cells through my respiratory system—not unlike its surveillance throughout my body for melanoma cells. When certain lymphocytes identify an otherwise healthy cell that’s been infected by the virus, it signals killer T cells to come in and deal with the invader, as I’ve written about before. We’d all be in pretty bad shape without those KT cells working so tirelessly for us. In fact, considering that a single flu virus in the body can multiply by the millions within seconds, it’s a wonder we don’t all topple over and die.

Since my immune system has already excelled in its standoff with melanoma, I’m assuming it will figure out this flu virus thing before long. That can’t come soon enough. Now that I’ve finished writing this, I think I’ll go lie down.