Can microbes that are harmful to us help other organisms?

According to recent studies, yes! Take, for example, the nematode. This little worm enters an insect, and when the time is right, realeses the bacteria that it is holding into the unfortunate prey, killing it. No one is yet sure why or how the worm knows which bacteria, but they think that the worm can recognize the proteins on the outside of the bacteria! Pretty cool, huh? Also, the Hawaiian Bobtail Squid, a tiny squid, uses the same bacteria that causes whooping cough, and gonorrhea in humans, which in the squid is responsible for the development of vital organs ! This suggests that the behavior of the bacteria depends on the host!

[kskerr]

Yes it is more than possible for a human pathogen to either help or not harm other organisms. Look at killer E. coli, that bug causes no issues in cattle but if a human contracts it watch out. Certain strains of salmonella are normal flora for lizards but potentially pathogenic to humans. Same with campylobacter in poultry.

One thing to note, whooping cough and gonorrhea are caused by two different organisms...

yeah, I know, I just didn't know how to put it clearly! Of course they're different organisms! Also, we have about a billion E.coli living in our intestine, producing vitamin K. Without E.coli, our blood wouldn't clot, and we'd bleed to death. As you know, it's only dangerous if it escapes the gastro-intestinal tract!

weird.

Isn't it?

[kskerr]

Not really, lots of things are like this. Just look at Austrailia, all the problems they have with critters that have been introduced there that are important parts of their native ecosystem but over there wreak havoc...