dinesh said:
Does direct transmission of a disease involve Kissing?
Or can it include paracites living on soil surfaces eg : hookworm?
Not really sure..can Stds be transmitted by kissing?
A disease that exhibits direct transmission means that it can be passed from one human to another, without needing a vector (e.g. a mosquito is needed for a protozoan a la malaria, or another kind of insect, a mammal, etc.) For example, avain influenza strain H5N1 has not yet been proven to exhibit direct transmission from person to person - you need to get near infected birds/droppings/eggs/etc. to get it. Same with anthrax, malaria, yellow fever, lyme disease, other arboviral diseases...blah blah blah. Lots of stuff can be transmitted directly - pneumonic plague, herpesviruses, hiv, etc. You get the idea. So, with that interpretation in mind, kissing could lead to direct transmission, depending on the organism in question. I, personally, would not want to kiss someone with active TB, or Ebola, or pneumonic plague.
I would not consider hookworm infections to be directly transmitted, unless, as someone so eloquently stated, it went directly via fecal-skin contact/oral/"I don't really wanna think about it" route. The worms/eggs have to exit the body (generally via feces? is there another route?), and then infect new hosts once they are "out".
And STD's transmitted by kissing? Well, herpesviruses (HSI and II), if remember correctly, can manifest as lesions on both genitalia and around the oral cavity - and both can be spread by kissing someone with sores. Eew. I don't know if mono is considered an "STD". I doubt it. There has been some research into HIV transmission via kissing, and I think that it has been demonstrated in rare cases (e.g. where children have shared a toothbrush and probably brushed their gums till they bled)...but I think that, for the most part, the genital area and the mouth area are pretty different environments, so anything that tends to live in one area is probably not gonna colonize the other.
Does that make any sense? Oh, yeah, and what the heck does this have to do with this forum??