AYESHA RASCOE, HOST:
Summer is coming. So are mosquitoes. Sorry to burst your bubble, but you might want to break out the citronella or the sterilized male mosquitoes. That's what officials in Southern California are doing. But how will that help, since it's the females who are after your blood? Joining us now to explain is Solomon Birhanie. He's the scientific director for the West Valley Mosquito and Vector Control District in San Bernardino County. Thank you for joining us.
SOLOMON BIRHANIE: Thank you for having me.
RASCOE: OK, first, just how bad is the mosquito problem in your part of the state?
BIRHANIE: It's really bad. So this year and, as you know, last year, we have got a lot of rain. So there's a lot of water all over the place, and that creates a very favorable condition for mosquitoes to breed.
RASCOE: So how does releasing sterilized male mosquitoes help? You know, I would think a female will still be able to mate with the free-roaming, non-sterilized male.
BIRHANIE: It's an old technique, actually, that has been around for many, many years. When you release sterile males, they'll go and compete with the wild males to mate with the females so that the females lay eggs which couldn't be hatched. So that's the idea. By releasing more numbers than the number of the wild males, we'll try to outnumber the wild males so that the sterile males will have a better chance of mating with females.
RASCOE: OK, because the females will have eggs that can't hatch. And then those females - they'll die off, and so then there won't be a next generation.
BIRHANIE: Exactly.
RASCOE: How long would that take to lessen the number of mosquitoes in an area?
BIRHANIE: Overall, these male mosquitoes, once they go out and mate with the females and then to see the impact on the next generation, it takes a few weeks.
RASCOE: How do you sterilize these male mosquitoes? Do you line them up and do a snip, snip, or what happens?
BIRHANIE: (Laughter) So we have X-ray machine. So what we do in the lab is we hatch them, and we'll only select the males to be placed inside the X-ray machine for a couple of minutes so that those mosquitoes are still active, but the only difference is they will be sterilized. It's a pretty simple procedure, and then those mosquitoes will be ready to be released.
RASCOE: Is this a better way of reducing the mosquito population than, you know, using insecticides or releasing genetically-modified male mosquitoes?
BIRHANIE: No, this is just an additional tool. Using mosquitoes to control mosquitoes is an idea in addition to all the other tools we have now. And we're not considering it as a silver bullet, but to use it - an additional tool in addition to what we have would be beneficial.
RASCOE: That's Solomon Birhanie, scientific director for the West Valley Mosquito and Vector Control District in San Bernardino County, Calif. Thank you so much for joining us.
BIRHANIE: Thank you for having me.
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