Public Service Announcement

[etumukutenyak]

DDT -- once used liberally to control external parasites and indirectly also controlled malaria/other internal parasites, it was banned in the US and other countries. However, many African countries continued to use it despite clear indications that mosquitos developed resistance to it rapidly. Now resistance to DDT is wide-spread in mosquito populations around the world, and malaria is still a problem.

Some anonymous idiot posted on matociquala about the poor African and South American children dying of malaria because we banned DDT. She quite rightly suggested paying for some mosquito netting, as that has been shown to be extremely effective in preventing malarial transmission via mosquito bites. It's cheap, it's effective, and it's a charitable contribution. Now you, too, can help prevent forest fires malaria.

Comments

[mjlayman.livejournal.com]

We had a lot of DDT when we were young. The Smokey Joe trucks would go by at least once an evening when we lived on tropical bases. Mother never let us run after the truck like a lot of kids did, but it was impossible to get away from the smoke.

And I was at the perfect age for that study that shows that girls exposed to DDT are more likely to get breast cancer. But my recent mammogram was normal, so I think I'm okay on that.

[etumukutenyak.livejournal.com]

There are a number of studies that show DDT to be non-carcinogenic, so it's got to be more than one factor. It was a fairly safe insecticide to use around humans, but it lost its effectiveness against insects fairly rapidly.

[mjlayman.livejournal.com]

The study (http://articles.latimes.com/2007/sep/30/nation/na-ddt30) is almost a year old, but I haven't seen it refuted. The age at exposure is apparently the important part.

[etumukutenyak.livejournal.com]

Then again, a study of Vietnamese women from North and South, with varying histories of exposure to DDT here (http://www.ncbi.nlm.nih.gov/pubmed/9419265) doesn't show that effect.

DDT is weakly estrogenic, so there is good reason to believe that it can change the risk of breat cancer. We've seen this in other estrogenic compounds, and the age at exposure is a good one to look at.

[mjlayman.livejournal.com]

That's interesting, although it's a test of current amounts like most of the others. The study I pointed to used preserved blood from the right age and then followed from there.

[etumukutenyak.livejournal.com]

Yes, and the Vietnamese study -- although it did not have blood from the time of exposure -- also followed two different populations of women, with historical exposure to DDT. Even though the only testing of DDT was on current blood samples, the patients were from areas of heavy DDT use. There's more to it than age at exposure, although that -- as for any estrogenic compound -- is going to be extremely important. Look at DES, where age at exposure related to the risk of certain types of cancer.

I'm mostly agreeing with you, and only pointing out that a single study where cancer risk is linked to DDT exposure isn't enough to make people think that DDT is carcinogenic after all. Estrogens and estrogenic compounds are funny things -- Asian diets are high in vegetables, which have a lot of phytoestrogens, and they tend to have low rates heart disease, which is strongly correlated to their diet. Once they move to a Western diet, the rates of heart disease in Asian women climbs to that of Americans. The rate of breast cancer in this population (Asian women on traditional Asian diet) is not as high as that of the American population (on a traditional Western diet). Part of this is the presence of soy isoflavones, or so researchers think. I used to do this research, back in my mis-spent yout'.

[mjlayman.livejournal.com]

I thought about the diet, we ate mostly what was common for the native where we lived, but I didn't realize soy had so much influence.

[fledgist.livejournal.com]

Mosquito netting over windows and beds, plus deet, plus moderate smoke (from mosquito coils), plus covering standing water, plus, of course, anti-malarial drugs are the standard prophylactic measures.

Working outdoors in smoke also helps (though, having done it, I assure you that this is a cure almost as bad as the disease).

[etumukutenyak.livejournal.com]

Yep, yep, yep. There's no one Silver Bullet against malaria. Perhaps someday they'll have an effective vaccine, which would be wonderful. (No more Lariam nightmares!)

[fledgist.livejournal.com]

An effective vaccine would be a wonderful thing indeed.