I expect most people know: (1) that the presence of this organism has been correlated with an increased risk for (a) stomach ulcers and (b) some types of stomach cancer; and (2) is inversely associated with childhood asthma.
Helicobacter pylori Colonization Is Inversely Associated with Childhood Asthma
Here's something perhaps rather newer to most of us.
Risk of Multiple sclerosis in females decreased by Helicobacter pylori infection Multiple Sclerosis News TodayThey found that patients with MS had lower H. pylori seropositivity (16%) than controls (21%); this decrease was observed in females while this was not seen in males. Notably, H. pylori seropositive females showed lower disability score when compared with seronegative females, while for males the authors observed the opposite, when the age at onset, year of birth and disease duration was similar. In addition, there was no significant correlation between H. pylori seropositivity and relapse rate.
The research team concluded that these findings suggest a protective role of H. pylori in the MS development.
This area just get more and more complex. And the people who are most confident with opinions seem to be those who know the least. I've certainly no idea what's going on, but I'm certainly interested to keep listening.
I recently heard Dr. Martin Blaser
talking to someone, Sean Croxton as I recall. It was an interesting interview - Sean's very good at drawing people out.
What I'll give, in case it interests anyone else, is the impression Dr. Blaser left me with as to the conception he has of this. I think this is best done in a "metaphorical" manner.
And, if anyone doesn't like this, I'm afraid this is, in any case, the nature of language:
We move in a reality we never can totally comprehend anyway. And even that's a bad way of putting it, because we're not really objects in reality so much as a perspective upon it.
So whatever will allow us to grasp something of what we're dealing with - and if we can come up with a better conceptualisation well and good.
Now I think the picture we're most commonly offered of bacteria of this sort currently is of the bacterium as a sub-contractor - it does this or that job for us. It's a taxi driver, a house painter, a wet-nurse. (No direct parallels intended there.)
Blaser, rather, seems to wish to emphasise that the key point is that we're dealing with something that has been there for a very long time. Estimates of how long H. pylori has been with us seem to have gone up from 60, 000 years to 100, 000 years - and now I think we're at 200 , 000 years. It seems to be common worldwide - and, if I didn't mishear or misunderstand, is different in different parts of the world (which if it's co-evolved with us is unsurprising). Doctors, however, seem to have conceptualised it as an "enemy" and many will try to eradicate it if they find it. To Blaser, as I took him, it's not an enemy, it's not a friend, it's not a subcontractor. It's just "always" been there. Now this is an important point. It means that since it's been there so long our immune system "assumes" it.
I'll give the picture that came into my mind.
Take a house - an old farmhouse with rough stone, or wattle-and-daub, walls. (That's your body.) There's a set of shelves on the wall that a carpenter came in and put up for the current owner's grandfather many years ago. (That's the immune system.) There's a bulge in the wall where a lump of stone projects quite noticeably. (That's the Helicobacter pylori.) When the carpenter made the shelves he cut them in such a way as to work around the bulge in the wall - he had to, simply because it was there. Now a new owner comes into the farmhouse and decides to smarten it up a bit. (This is your doctor.) Among other things he decides the bulge in the wall looks unsightly and really won't do. Accordingly, he takes a cold chisel and a lump hammer (these are his drugs) and knocks it off. (This isn't necessarily a bad thing, and it could be that the wall has settled and made the bulge more prominent and something of a problem where it hadn't been before. But that may be debatable.) However, the shelves were made to fit round the bulge, and now he's smashed it off, the shelves no longer work as they did: stuff can now roll down the back of them.
As I say, I think this is the kind of way Blaser sees the situation, and I've put it put into a story form, whether adequately or not I can't say. Interesting to look at the problem from this point of view, though.