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"How can I tell if my infection is viral or bacterial?"

ZocdocAnswersHow can I tell if my infection is viral or bacterial?


Pretty sure I have an infection in my chest. Been coughing and congested for weeks. How can I tell if its viral or bacterial? Will it heal on its own either way?


As you are probably aware, a virus is not a living organism, and is not able to multiply on its own. In order for a virus to duplicate, it must infect and sort of hijack the host's DNA replication apparatus. This means that there is usually a period of time, after infection, where the virus multiplies within the host where there are no significant symptoms until the "viral burden" gets high enough. This is called the prodromal phase. The typically means that viral infections start out with mild symptoms, that slowly progress, then taper back off. Most viral illnesses (like the common cold) run their course in about 7-10 days. Nearly all viral illnesses (save a few specific viruses) are not treated with anti-viral medications, and the hosts immune system takes care of the infection. Unfortunately symptoms are not very specific, and make it difficult to determine if an infection is viral or bacterial. Obviously bacterial infections respond to antibiotics, whereas viral infections do not. It is possible to develop a bacterial superinfection on top of a viral illness. Typically this results in a persons symptoms getting markedly worse acutely (such as a spiking fever, chills, sweats, etc). If you are worried that your cough has become a bacterial infection, I would recommend making an appointment with your primary care physician, or even a pulmonologist. I wish you all the best.

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