It is my understanding that, once you recover from a cold, you are forever immune to that particular cold virus. It is also my understanding that there are an estimated 200 to 300 cold virus in existence.
But does this mean that it possible to be infected with more than one cold virus at a time?
The reason I’m asking is because an acquaintance and I both have a cold. Therefore, we reasoned that we do not have to be concerned about “catching” a cold when we’re in the same room. I believe this would be true is we were both infected with the same virus, but what if we were infected with different viruses?
One of your basic assumptions is wrong. If you search the SDMB you will find a thread that I asked within the last couple of months on why I keep getting colds when I must’ve had over the 200 different types of viruses they say cause a cold.
Smeghead informed me that because I catch one cold virus, does not mean that I can’t be infected by that virus again. The reason, he said, is because the Ige antibodies must be stimulated for lasting immunity, but the cold viruses only stimulate the IgM (I believe that’s the one), which doesn’t confer long-lasting protection.
He also pointed out that all cells die, including these memory cells. So if you can catch two different cold viruses at the same time? How would you be able to tell. Perhaps Smeghead can once again come to our rescue.
Actually, IIRC, there is a period of time after being infected that you would be immune to that specific strain. A couple of weeks, I think. But like Smeg said, the immunity is not long lasting and you will eventually be susceptible again.
Considering you are almost assuredly infected by several herpesviruses at the moment (Thats not an insult, just a statistical likelihood) it is quite possible to be infected by more than one cold virus.
I was at the doctor on Friday for this lingering cold I’ve had since Thanksgiving. She asked me to run through my symptoms as they happened, and I noted that I very oddly started to get body aches a week into it, even though I never get aches with a cold. She said “Well, maybe you caught another virus.” She didn’t seem to think that was a remarkable possibility.
"It is my understanding that, once you recover from a cold, you are forever immune to that particular cold virus. It is also my understanding that there are an estimated 200 to 300 cold virus in existence. "
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In that case, at my rate, i’ll be permanatly cold free in a few years.
It’s IgA, actually, that protects the nasal mucosa, and it only lasts a few months at most. Sorry if I misspoke before - that was towards the beginning of my immunology class, which I have since finished.
As to the double infection, I’d say yes. Sort of. I know, typical biology answer. The thing is, when you get virus #1, you start up an immune response. This includes specific immunity, like T cells, antibodies, etc, which would not affect any other virus; but it also includes nonspecific immunity, like swelling, activation of macrophages, etc, which would make infection with another virus much more difficult, though not impossible.