The life span of viruses, bacteria and other nasties

I was diagnosed with a bacterial infection in my upper resperatory tract yesterday, and I felt like shit…I couldn’t talk, I was coughing up phlem (sp?) and other nasties so my mind was drifting. So, I started thinking about something.

How long do bacteria and viruses live outside of their host?

From what I remember of Biology 10, Viruses last longer than bacteria. But I was thinking about this. Lets say I was on a business trip and staying in a hotel and I had a cold. I know most hotels change the sheets after a stay, but I also know that not all change the other bedding. Would that person be at risk of catching my cold? How about what I have now, a sickness from caused by a bacteria. Would the bacterium die shortly after it is out of its warm, moist cozy home called my Trachea? How long would it be a threat to others? 1 hour? 6? 24?

Surely some of the great minds on the board must know the answers to these questions.


Signed, a sick bernse.

Depends. It varies widely.

Some viruses, like HIV, can’t survive for more than a couple of minutes outside a host. Others, like some cold viruses, can survive on inanimate objects for days or weeks or longer.

Bacteria also vary. Most will die pretty quickly without a source of nutrients. OTOH, many can live on a pretty scarce supply. There are some bacteria that form spores when faced with starvation, and some of those spores can survive for decades. There’s a sample of (IIRC) anthrax spores that were collected in the 30s that are still viable.

Back in October some scientists announced that they had apparently revived some bacteria that were trapped in a salt crystal for 250 million years. I would, of course, take this with a huge grain of salt (ha ha) but the fact that some people took it seriously gives you an idea of how durable bacterial spores can be. Here’s a story about it:

Viruses don’t really “live” anywhere, but there are some bacteriophages that can stay viable for extremely long times on laboratory surfaces and cause problems for people trying to grow bacteria. The way some viruses are constructed, it would be reasonable to think that they could stay viable indefinitely if they were dried out and kept from getting too hot.