Bad News for Parasites

If you're a malaria parasite, this season doesn't give you much to be thankful for. A team at Rensslaer Polytechnic has identified a key chemical receptor which Plasmodium parasites use to infect humans and mosquitos. Block the receptor, and malaria can't spread. Bad news for malaria, and good news for humans.

Between one and three million people die of malaria every year, most of them children. Spraying with DDT in the 1950s cut back on malaria infections considerably, but the disease has made a comeback as environmental concerns limited pesticide spraying. A drug to block the infection would break the human-to-mosquito cycle and put malaria on the endangered list.

Comments

[Thom H.]

I'm curious. Is there a down side to this? One of those unintended consequences? Will changes in the Plasmodium population affect the mosquito population? It seems obvious that it would have some effect on the human population, i.e. fewer malarial infections and deaths in those areas prone to malaria. What else? Difficulty in supporting a population boom? A human migration into previously unlivable areas, and a consequent degredation of the associated wetlands?

[Cambias]

Thom:

Well, if the consequences are unintended, nobody's going to know about them beforehand.

Malaria's caused by Plasmodium protozoans. They are parasites, cycling between mosquito and vertebrate host. As near as I can tell, the ones that prey on humans don't infect other vertebrates.

As to the problem of a human population boom -- I think there are better ways to protect wetlands than hoping millions of people die.

[Thom H.]

>"Well, if the consequences are unintended, nobody's going to know about them beforehand."

Not necessarily. Sometimes the implementers of a plan ignore the flag wavers at the back of the crowd. There have been projects whose detrimental effects could have been predicted IF someone had stopped long enough to do some studies or paid attention to data that alrady existed.
In any case, it seems on the surface that eliminating Plasmodium sp. would be less detrimental than, say, eliminating mosquitos. Not that I like mosquitos but I'd hate to see Gambusia and dragonflies starve to death. It's that kind of unintended consequence that I was really thinking of, i.e. does plasmodium constitute a link in some chain such that breaking it will create a larger problem. if not, then, "so long Malaria, glad to see you go." The change in human population demographics was less of a concern but maybe something we should still think about. It's a "forewarned is forearmed" sort of thing.