Latest Zika News

Zika continues to be in the news. 

The country of Columbia has widespread Zika virus. But Columbia is claiming that they are not seeing the increase in microcephaly that is being found in Brazil. There is no known explanation for this discrepancy. The scientists in Columbia that are not absolutely convinced that Zika causes microcephaly. Columbian scientists think that this connection between Zika and microcephaly might be scientific misdirection based on bad statistics. What amounts to a correlation/causation fallacy. This kind of scientific fallacy has happened plenty of times in the past. As of yet I think that most people believe there is a link between Zika and microcephaly. 

Correlation/Causation fallacies are very easy to fall into. I remember when hairy ears were thought to be connected to heart disease. So people would trim their ears, as if that would help their heart. It was ridiculous. And in my field, it was thought that estrogen treatment for older women prevented heart disease. It required many years to correct this wrong idea. We now know that estrogen treatment is preferentially taken by fit women. This explained the fact that women on estrogen hormones had less heart disease. In a randomized trial, there was no protection from heart disease. This false conclusion took many years to correct. 

The estrogen link to breast cancer is still not understood at all. Even by very smart people. Estrogen is about as carcinogenic as a nose. It is a normal part of a woman's body. (Please note that noses do form cancer.) In the Woman's Health Initiative it was found that estrogen increased the breast cancer risk in women about 7 in 10,000 cases. But it similarly lowered the risk of colon cancer. So in the worst case scenario the cancer risk is a wash. Also note that changing 7 cases from colon cancer to breast cancer should save lives. In the WHI, after two years, the increased breast cancer risk was just about gone. The risk line was just about to cross over to lowered risk (consistent with many older studies) when the WHI was cancelled prematurely. I would invite anyone to go and read the WHI report and see that the risk for breast cancer was just about to cross over into protection. There is one graph that shows this. Cancelling the study early was a violation of the study protocol and wiser calmer heads should have kept the study going. 

The Aedes mosquito continues to spread. It is an invasive species anywhere in the Americas, so eliminating it should not damage the ecosystem in any way. Right now there are plenty of videos of insecticide trucks fogging entire cities, and workers with leaf blower sized backpack devices fogging inside homes. There appear to be an army of them working in South America. 

Even though removing Aedes mosquitoes will not hurt the environment, widespread insect fogging may have a detrimental effect on the environment or on human fetuses. It will certainly create resistant forms of other insects. 

There is no chance that insecticide is going to remove Aedes. There are just too many of these mosquitoes in too many places. Insecticide will reduce them, but it will not eliminate them. So humans are now seemingly committed to large scale long term continuous insecticide exposure everywhere there are Aedes mosquitoes. 

There is a much better strategy that has worked in the past. It is mosquito birth control. There is a British biotech firm, a small firm, that can create sterile Aedes male mosquitoes. These mosquitoes then go and mate with wild female Aedes. The offspring will not grow to adulthood. This British firm has also tagged their Aedes mosquitoes with a color that glows red in the presence of some kind of special light. Maybe a black light. This is a great way to follow the progress of their birth control measures. As a Gyne, I am familiar with birth control. Birth Control sometimes works. 

Here is a news story that is right now 3 hours old, at the Independent News in the UK: 

http://www.independent.co.uk/news/uk/home-news/zika-british-team-say-they-have-a-remedy-for-the-virus-a6859046.html

So if the sterile males go out into the wild and shoulder aside their more fertile cousins, then the Aedes mosquitoes will not successfully reproduce. 

So birth control can work. There are several theoretical problems here. According to the principle of natural selection, the more fertile members of a species should survive. So if there are some female Aedes out there that can smell out their nonfertile mates, and not mate with them, then this won't work for them. Also, fogging of insecticide will kill the Sterile males too, so those two methods will work against each other, not support each other. This exact birth control technique has been used in the past to remove pests from agriculture. It sounds a lot safer than insecticide to me. 

I tell my pregnant patients to avoid insecticide while pregnant. There are not enough studies to prove that these chemicals are safe for fetuses. It may be that fogging reduces Aedes, but that pregnant women exposed to insecticide have some other birth defects from the insecticides. Hopefully someone has figured out that risk. Eventually, the scientists will get to the bottom of this. 

Thanks for reading. 

Dr John Marcus 

blog at doctorjohnmarcus.blogspot.com 

89 North Maple Ave 

Ridgewood NJ 07450 

Comments are welcome.