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Hank clarifies the misconceptions about Chagus disease, discusses a couple of interesting celestial events - one that happened in the past and one that will happen in the distant future, and sheds more light on the benefits of sexual reproduction.

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Hi and welcome back to the office for another episode of SciShow news where, today, I'm gonna bust some recent myths about AIDS, reveal two celestial events that you probably didn't know about and explain some new insight into how and why we have sexy-times. You ready?

This time, I wanna get your mind right about Chagas. A disease, which has been getting some pretty hysterical media attention in the past couple of weeks. All because of a recent study that likened it to the AIDS epidemic. 

So then immediately cable news and morning talk show types started calling Chagas "The New AIDS" and some online media have been describing it as "an AIDS-like disease", but here's the facts.

Chagas is nothing at all like AIDS, and it's not an epidemic. It's caused by tiny parasites transmitted by biting insects called triatomines that are most common in Central- and South America.

Many who are infected with the parasites don't notice symptoms for years - even decades - but, once the parasites enter the blood stream, they can infect vital organs including the heart, brain and intestines. This happens to about 30% of patients.

There is no cure, and there are only to drugs that can treat the infection, but the side-effect are so severe that neither of them has been approved for sale in the United States. 

The CDC estimates that about 300,000 of people in the US may carry the Chagas parasite, but the vast majority of them contracted it in Latin America, where the vector insects mostly live.

So, how the frick did the media manage to turn Chagas, a parasitic disease that targets vital organs, into AIDS a sexually transmitted viral disease that compromises the immune system?

Well, they're idiots, first of all. But we found out that the misinformation stems from a perfectly reasonable report published in the journal "PLoS Neglected Tropical Diseases" - a publication that I am adding to my list of things that I'm glad exist.

The study merely said, that Chagas today resembles the early decades of the HIV epidemic because both are chronic conditions that disproportionately affect poor people who don't have access to treatment. 

There are some pathological similarities, like both diseases can be transmitted by blood transfusions or by a pregnant woman to her fetus, but the comparison ends here.

So, hey, reporters, next time you wanna write about science, do what SciShow does, and read the freaking research. And you, dear viewer, can read it yourself in the links below.

Another thing you might have heard about was an ominous-sounding press-conference that NASA astronomers held concerning "The Future of our galaxy". And, hey, I have good news!

Turns out that the Milky Way is on a collision course with the Andromeda galaxy. You heard me, in a mere 4 billion years Andromeda, also known as M31, is going to slam into us like Mel Gibson in a Maserati, resulting in a merger of the two galaxies. 

Observations by the Hubble Space Telescope lead astronomers to recognize the impending collision, which is being caused by the gravitational pull of the two galaxies and the dark matter surrounding them.

Based on NASA simulations, the galaxies may actually pass through one another first, and then over the course of a couple billion years be drawn back together by gravitation, forming a new elliptical galaxy.

Now because celestial bodies inside galaxies are so incredibly far apart, galactic collisions don't impact individual planets or stars. So even though it doesn't sound like it makes senses, NASA says that the Earth and the Sun won't be affected by this intergalactic merger. Will the... Will the Sun even exist then anymore?

So, you know, whatever, big deal. What I'm concerned about is that we only have 4 billion years to figure out what to call this new supergalaxy. Milky 31? Andromeda Way? Spokane? I would like to see your nominations in the comments below.

Now here's another space event that you probably didn't know about. Astronomers just revealed that on May 17th, my wife's birthday actually, a solar flare sent a jet of material toward the Earth with so much energy that it caused a cascade of particles to shower down over the planet, actually raising radiation levels on the Earth's surface.

This is the first time such an event, called a ground-level enhancement, has happened since 2006, and experts say that it signals that we're near the peak of the Sun's 11-year solar cycle. But don't let the boring name fool you. Ground-level enhancements are actually really cool.

Charged particles from the Sun strike the atmosphere with so much energy that they break apart molecules in the air. Those energized fragments go on to split other molecules and the reactions continue until a torrent of high-speed protons and neutrons rain down on the Earth. Scientists are puzzled, though, as to why a relatively minor flare would cause this kind of radioactive cascade.

But really, once again, "ground-level enhancement"? Scientists, you are so bad at naming things. I have a vote! My proposition is "neutron storm"!

Finally, you've probably seen our latest infusion on the social, biological and evolutionary advantages of monogamy, and as it happens, new research in the Journal of Science adds to our understanding of monogamy's origins. 

Biologists at the University of Texas have found that the brain circuitry that we use to perform complex social behaviors, especially those related to the sexy-times, is the same in all vertebrates, and it dates back some 450 million years.

Studying 88 species of fish, birds, reptiles, and mammals, including humans, the scientists looked at 12 regions of the brain, responsible for things like mating displays, parenting and monogamous behavior. They found, that they were basically the same across all of them, even really simple animals that don't practise all of these behaviors.

Now this doesn't mean that monogamy is genetic, I mean look at John Edwards for examples, but it does suggest that the ability that some animals have to do tricky things like be faithful to their mates evolved with that same ancient set of circuitries.

Now you probably also saw a recent dose on why sex is a thing at all. Well a new study claims to prove that sexual reproduction makes healthier organism. And no, I'm not talking about burning calories.

Instead biologists from the US and Canada studied primrose flowers. Some of which reproduce asexually, while others do it the sexy way. All primrose produce an enzyme that fights dangerous mildew and the study found that the gene responsible for making that enzyme had changed in what's called the sexual plants from what the asexual plants had.

Since sexual plants swap genetic in formations when they reproduce, that gene had adapted over time, and it turned out that the beneficial gene was expressed more in the sexual plants, so they were healthier, produced more fruits and had more offspring.

Totally makes sense, when you think about it, but hooray for sexual reproduction! And also, I got to use the phrase "sexual plants".

Thanks for watching this episode of SciShow News if you have questions or comments or ideas please leave them in the comments below or get in touch with us on Facebook or Twitter, and we'll see you next time!