Why is the Flu Seasonal?


The 2012-2013 flu season is shaping up to be a doozy. The Centers for Disease Control and Prevention have reported that during the first week of 2013, 7.3 percent of all deaths reported through their 122 Cities Mortality Reporting System were due to pneumonia and influenza, crossing their threshold for an "epidemic." Boston has declared a public health emergency, flu cases have tripled over last year in Washington, D.C.El Paso and elsewhere, and a Pennsylvania hospital has had to set up a tent outside their ER to accommodate the crush of flu patients. 

Before the dust and the snot have even settled, the director of the National Institute of Allergy and Infectious Diseases warns that this might be the worst flu season we've seen in a decade. But why is the illness seasonal?

In the temperate regions of the world, the flu tends to strike hardest in the autumn and winter. The conventional wisdom used to be that the influenza viruses either went into a dormant state or persisted at very low levels during the summer months before flaring up again. Scientists have since figured out that, instead of simply lying low during their "off season," the viruses also go globe-trotting, and get transmitted throughout populations all over the world.

In 2007, researchers from Pennsylvania State University and the National Institutes of Health found that the influenza A virus uses its summer travels to meet exotic viruses in tropical areas (which experience year-round flu virus activity), swap genetic information with them, and then roll back into town with enough genetic differences to fool our immune systems. 

Scientists are still working out what exactly triggers the reintroduced viruses to infect people during the fall and winter. The PSU team and scores of other researchers have proposed several explanations, which might work alone, simultaneously but separately, or in combination with each other:

Weather and climate

Influenza viruses do very well in cold winter temperatures and the dry air that goes with them. They can survive longer in dry air than moist air, and hold out longer on exposed surfaces (counters, doorknobs, keyboards, etc.) when they're cold. For humans, dry air means dehydrated mucus and drier nostrils and airways, which could make it easier for the viruses to make themselves at home once they're passed to us. A study on guinea pigs at the Mount Sinai School of Medicine showed that the transmission of influenza is enhanced in cold (41 degrees), dry (20 percent humidity) conditions and declines as temperature and humidity rise (at 86 degrees or 80 percent humidity, it wasn't transmitted at all).

Human behavior

Fall brings a new school year and cooler outside temperatures, and more people spend more time indoors in close contact with each other, giving the viruses an easy route for transmission between hosts. Even in tropical regions that don't have a winter and where flu occurs throughout the year, illness tends to spike during the rainy season when people spend time together indoors.

Human Physiology

Thanks to all that time indoors and the short winter days, our bodies' Vitamin D decreases in the winter. This decrease — or any number of other seasonal tweaks to our immune systems — could leave us more susceptible to the virus for a few months out of the year and act as a "seasonal stimulus" for flu infection. 

Courtesy of October Films
This Scientist's Idea of the 'Perfect' Human Body Is Kind of Terrifying
Courtesy of October Films
Courtesy of October Films

The perfect human body has the legs of an ostrich, the heart of a dog, and the eyes of an octopus, according to anatomist Alice Roberts. And it’s utterly terrifying.

With the help of anatomical artist Scott Eaton and special effects designer Sangeet Prabhaker, Roberts created a life-size replica of herself that fixes many design flaws inherent to the human body, Motherboard reports. Roberts unveiled the sculpture on April 23 at the Science Museum in London. On June 13, the BBC released a documentary about the project.

Among the flaws Roberts’s sculpture corrects are humans’ inferior ears, spine, and lungs. Roberts borrowed anatomy from reptiles, birds, and other mammals to create a Frankenstein-esque creature straight from the island of Dr. Moreau.

The sculpture of Alice 2.0, left, with Alice Roberts, right
Courtesy of October Films

The sculpture has legs like an ostrich because, as Roberts says on her website, the human knee is complex and prone to failure. Like humans, ostriches are bipedal, but they are far better runners. Bird-like lungs that keep air flowing in one direction, not two, make running and other aerobic activities easier for the perfect human to manage. And a chimpanzee’s sturdier spine and a dog’s heart (which has more connected arteries, leading to lower heart attack risk) make Roberts’s alternate self more resistant to injury and disease.

Roberts’s ideal human body also has skin like a frog that can change shades based on the environment, and large, bat-like ears that amplify sound. Roberts also fixed humans’ backwards retina, which produces a natural blind spot, by borrowing from octopus eye anatomy.

Perhaps most disturbing of all is the baby head poking out of the sculpture’s marsupial pouch. Roberts says marsupial pregnancy would be far easier on the human body and more convenient for parents on the go.

“This could be a human fit for the future,” Roberts says at the end of a trailer for her BBC documentary.

[h/t Motherboard]

Employees at Antarctica's McMurdo Station Are Throwing a Party for Pride Month

Employees at Antarctica's McMurdo Station are gearing up to celebrate Pride month in one of the world's harshest environments. On Saturday, June 9, the station will host what Hannah Valian, who deals with the center's recycling efforts, calls "one of the larger parties ever thrown" at the station.

McMurdo Station is an Antarctic research facility owned and operated by the United States. The station is more sparsely populated during Antarctica's colder autumn and winter seasons (which run from March to September), but employees tell us there's still a decent-sized LGBTQ scene to celebrate this June.

About 10 of the 133 people currently at McMurdo identify as LGBTQ, says Rachel Bowens-Rubin, a station laboratory assistant. Valian said the idea for a Pride celebration came up in May at one of the station's regular LGBTQ socials.

"Everyone got really excited about it," she tells Mental Floss via email. "So we ran with it."

Ten individuals are wearing coats while holding a rainbow-colored Pride flag. They are standing in snow with mountains in the distance.
"I hope when people see this photo they'll be reminded that LGBTQ people aren't limited to a place, a culture, or a climate," McMurdo's Evan Townsend tells Mental Floss. "We are important and valuable members of every community, even at the bottom of the world."
Courtesy of Shawn Waldron

Despite reports that this is the continent's first Pride party, none of the event's organizers are convinced this is the first Pride celebration Antarctica has seen. Sous chef Zach Morgan tells us he's been attending LGBTQ socials at McMurdo since 2009.

"The notion is certainly not new here," he says.

To Evan Townsend, a steward at the station, this weekend's Pride event is less a milestone and more a reflection of the history of queer acceptance in Antarctica.

"If anything," Townsend says, "recognition belongs to those who came to Antarctica as open members of the LGBTQ community during much less welcoming times in the recent past."

This week, though, McMurdo's employees only had positive things to say about the station's acceptance of LGBTQ people.

"I have always felt like a valued member of the community here," Morgan tells us in an email. "Most people I've met here have been open and supportive. I've never felt the need to hide myself here, and that's one of the reasons I love working here."

Saturday's celebration will feature a dance floor, photo booth, lip sync battles, live music, and a short skit explaining the history of Pride, Valian says.

"At the very least, I hope the attention our Pride celebration has garnered has inspired someone to go out and explore the world, even if they might feel different or afraid they might not fit in," Morgan says. "'Cause even on the most inhospitable place on Earth, there's still people who will love and respect you no matter who you are."


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