Chikungunya virus spreads in Americas, enters U.S. via travelers

The aggressive tiger mosquito, distinguished by its white stripes, can spread chikungunya virus. This mosquito is native to Southeast Asia but has invaded other parts of the world in recent decades, including much of the United States. (Photo by James Gathany/CDC.)

By Carol Clark

As chikungunya virus moves into the Americas for the first time, causing a major outbreak throughout the Caribbean and parts of Central and South America, U.S. health officials are monitoring cases in travelers returning from the affected areas. Imported cases of the mosquito-borne virus have been confirmed in more than a dozen U.S. states, and that number is expected to keep growing.

“Early response is essential,” says Gonzalo Vazquez-Prokopec, a disease ecologist in Emory’s Department of Environmental Sciences who studies how mosquito-borne pathogens move through urban populations. “We need to prepare the country to try to avoid what we suffered with the introduction of West Nile virus 10 years ago.”

Vazquez-Prokopec and Uriel Kitron, chair of Emory’s Department of Environmental Sciences, have been studying the patterns of vector-borne disease epidemics for years and are currently working with public health officials in other parts of the Americas and Africa on chikungunya control efforts.

Kitron will be a featured speaker at a meeting of the NSF-sponsored Urban Climate Institute, hosted by Georgia Tech July 9-10. His talk is titled "Changing Urban Climate and Mosquito-borne Diseases."

The World Health Organization reported the first local transmission of chikungunya in the Western Hemisphere in December of 2013, on the island of Saint Martin. Local transmissions means that mosquitoes in the area have been infected with the virus and are spreading it to people by biting them. Since then, more than 150,000 cases of local transmission have been identified in 17 countries or territories in the Caribbean, Central and South America, according to the Centers for Disease Control and Prevention. Puerto Rico is the only U.S. territory or state that has identified a case of local transmission, the CDC reports.

Chikungunya is rarely fatal but the symptoms can be severe and debilitating, including headache, fever, joint and muscle pain, and joint swelling or rash. While most patients recover within a week, in some people the joint pain can persist for months. Newborns, older adults and people with existing medical conditions are at higher risk for the more severe forms of chikungunya.

The foot of a chikungunya patient in the Philippines shows the characteristic swelling and rash. (Photo by Nsaa.)

There is no vaccine to prevent the disease or medicine to treat infections. The only way to avoid infection is to prevent mosquito bites by using repellent, window/door screens, and reducing the number of mosquitoes by emptying standing water from containers.

The virus is primarily spread to people by two types of day-time biting mosquitoes: Aedes aegypti and Aedes albopictus. While the former is not common in Georgia, the Aedes albopictus, or Asian tiger mosquito, is pervasive. It is that tiny, infuriating, white-striped pest that crashes countless backyard barbecues, and turns many a relaxing summer session in a hammock into a bloody battle.

“They are like the cockroaches of mosquitoes,” Vazquez-Prokopec says, “perfectly adapted to living in urban areas in close proximity to humans. A house is like a microhabitat for both these species, which can breed in the little bit of water collected beneath an indoor flowerpot.”

The tiger mosquito bites not just people but a range of animals, including squirrels, dogs, deer and birds. The Aedes aegypti, however, which thrives in tropical climates like the Caribbean, feeds solely on human blood.

The Aedes aegypti mosquito is the primary spreader of chikungunya in the current outbreak in the tropical region of the Americas. This mosquito species is an especially efficient spreader of human disease since it only feeds on human blood. (Photo by Muhammed Mahdi Karim.)

“No one has immunity to chikungunya in in the Americas, causing it to spread like a fire and create a real problem for public health,” Vazquez-Prokopec says, noting that in poorer countries fewer homes have air-conditioning, or even window screens, to keep mosquitoes at bay.

Once a mosquito become infected, by taking a blood meal from an infected person, the mosquito can then spread the virus if it bites another person.

“The way the virus is propagating, we expect local transmission of chikungunya to make it to Mexico’s Yucatan Peninsula as early as this summer,” Vazquez-Prokopec says. “It’s just a matter of time.”

He is currently coordinating a chikungunya rapid-response effort for the Yucatan Peninusula. The effort involves health officials from the three states making up the peninsula (Yucatan, Campeche and Quintana Roo) as well as researchers from local universities. “We want to use our experience researching mosquito-borne disease propagation to help the local authorities try to predict when and where the virus will move,” Vazquez-Prokopec says. “There are two ways of attacking a fire: You try to contain the fire and you also look at where the fire is likely headed to create a buffer to help extinguish it. We know we are in front of a major challenge,” he adds, “but we hope our approach can reduce the chances of a major outbreak occurring in the peninsula.”

Brazil, which reports the highest number of dengue fever cases in the Americas, is another likely destination for serious outbreaks of chikungunya virus, adds Kitron. He is currently in Salvador, Brazil, a city where dengue is highly endemic, collaborating on an entomological study of Aedes aegypti and Aedes albopictus, which are also vectors for dengue.

Chikungunya virus has long been endemic in Africa and parts of Asia. More recent outbreaks have occurred in Europe and countries in the Indian and Pacific Oceans.

Related:
Sewer upgrade flushes West Nile virus vector from Atlanta stream
Dengue study to focus on asymptomatic carriers

Anatomy of an economic meltdown

The 2007-2008 crisis wasn't due to "immoral, greedy bankers who created toxic assets for which they got inflated ratings and sold to stupid investors," Gorton said. "If banker greed causes crises, we'd have one every week." (Photo by Wilford Harewood.)

By Leslie King, Emory Report

What caused the financial crisis that began in 2007, that time of cutbacks, job losses and housing foreclosures? And how can another crisis be prevented?

Yale professor Gary Gorton discussed causes and effects of recessions in a workshop on financial and monetary history held May 21 at Goizueta Business School.

Gorton came to national attention in September 2010 when then-U.S. Federal Reserve Chairman Ben Bernanke, testifying before a national commission on the fiscal crisis, referenced Gorton's work as recommended reading for understanding the crisis.

One small factor that set off the panic in 2007 was the news media, Gorton said.

"The press didn't really do a very good job of explaining what was happening. But it's hard to blame them. They called economists and economists had no idea. If you call the experts and the experts don't know, how are you supposed to know? And the press — they're never going to get it right because the people who know aren't going to talk and the people who talk don't know," he explained.

"And in Congress, these people have nine million things they have to be experts on; they can't be experts on everything. In a lot of ways, it was a failure of the economics profession to explain things apparently in a way that the public could understand and that will lead to good policy."

Read more of Gorton's analysis in Emory Report.

Gorton recommends Franklin Roosevelt's first radio address, in March 1933, to learn some of the mechanics behind both the Great Recession and the 2007-2008 crisis. Click on the YouTube video below to listen: 

Crushing myths, pinning down facts about insects

What does an adult luna moth eat? Nothing, because it has no mouth. These short-lived insects are among those that students collected and are displaying in the halls of the biology department, along with posters on the interesting characteristics of 12 different insect orders.

By Carol Clark

“The first day, I flinched,” says Emily Fu of the Emory Maymester course “Insect Biology.” She recalls feeling queasy as the professor, Jaap de Roode, showed a series of close-up images of creepy crawlers.

“I was seriously considering dropping the class. But as we learned more about them, and how awesome they are, I actually started to appreciate them,” says Fu, a junior majoring in biology and psychology. “Insects are really complex and much smarter than most people realize.”

Fu and the 11 other undergraduates in the class created a buzz in the biology department recently when they unveiled dozens of pinned and mounted specimens they collected during four field trips. The students also displayed scientific posters they created for insect orders that particularly intrigued them, wowing guests at the reception with their newfound knowledge.

Add crunch to your lunch: As the human population burgeons to 9 billion, insects are looking like the future of food, according to a recent U.N.report.

The female large blue butterfly, for instance, has evolved to hang out around ant nests. The butterfly lays eggs that hatch into caterpillars that look like, and smell like, an ant larva. “Some ants are tricked into taking care of the butterfly larvae,” Fu says, adding that the ants will even fight to protect the butterfly babies from parasitic wasps that try to lay their eggs inside them. When the ants attack one of these egg-laying wasps, however, the wasp releases a pheromone that drives the ants into a frenzy. The ants end up attacking and killing each other instead.

“A lot of crazy stuff is going on in the insect world,” muses Tufayel Ahmed, a senior majoring in biology.

A snack table was laid out with nacho-cheese Doritos, mealworm beetle larvae seasoned with Mexican spices and salt-and-vinegar crickets.

“The crickets are a bit stale,” warns Wilson Hunt, a junior majoring in biology whose poster was entitled “Orthoptera as Food.” While they may not be fresh, he adds encouragingly, they contain 60 percent protein, versus only 18 percent in a burger.

In addition to new culinary experiences, the reception gave guests a leg-up on vocabulary.

“Every bug is an insect, but not every insect is a bug,” says Alycia Patton, a senior majoring in biology. She explains that the forewings of true bugs, one branch of an evolutionary tree, are thick and leathery where they attach near the body and thin and membranous near the tips. Another defining feature: Mouth parts that can pierce the tissue of a plant or another insect.

Patton traces her love of entomology back to her childhood. She enjoys finding unexpected beauty in the tiniest of insects, like the vivid colors of the candy-striped leafhopper.

But she reserves her highest praise for the homely mole cricket. “Its front legs have little scoops on them so that it can dig tunnels,” Patton says. “The males build the tunnels in a way that amplifies its mating calls. It creates its own sound system.”

Maura Sare, a junior majoring in biology and environmental sciences, overcame an aversion to touching insects during the class field trips. “Most insects aren’t going to bite you,” she says, and many have evolved much more interesting ways of protecting themselves.

Take the stick insect. “If a predator grabs one of its legs, it can just detach it and get away,” Sare says. And they have fantastic camouflage, she adds. “We actually don’t have any examples of stick insects here today. We couldn’t find any.”

Stone Mountain was the site of one of the class collecting trips.

Alexander Heaven appreciates saturniids, including the large, lime-green luna moth, “because they’re pretty,” and because that beauty is ephemeral. “An adult luna moth doesn’t have a mouth, so it can’t eat,” Heaven says. “When they emerge from the cocoon, they have about five days to find a mate before they just fade away.”

Heaven, a sophomore majoring in environmental sciences, is also a big fan of the praying mantis. “During mating, the female mantis will cannibalize the male,” he says. “She’ll turn around and rip his face off. That’s awesome. They’re just really great predators, the best at what they do.”

Biology major Kevin Flood points to a pinned example of another great predator, the robber fly. It looks like a bee, but that’s a trick of mimicry designed to lure real bees near so the robber fly can eat them, Flood says. “See that needle-like thing coming out of its mouth? It wraps its legs around the bee, sticks the needle in, liquefies the bee’s insides and then sucks them up like a straw.”

As if bees didn’t have enough to worry about.

Head first: Biology post-doc Daniel Kueh dropped by the reception and learned that crickets are like potato chips. It's hard to stop at just one.

Pesticides and pathogens have been linked to a rise in colony collapse disorder, which is causing mass disappearances in honeybees. The issue is under intensive study due the importance of these insects, says Nikki Mehran, a senior majoring in biology.

“I was surprised to learn how many food crops that honeybees pollinate,” she says. “One-third of our diet would be missing if all bees suddenly disappeared.”

Mehran says the fieldwork was her favorite part of the class. “We got to go to Stone Mountain and I’d never been there,” she says. “After coming out of finals and being trapped inside, it felt good to get out in nature. I had a great time.”

The “Insect Biology” class was launched this spring by Jaap de Roode, an evolutionary biologist whose lab is one of only a handful in the world focused on monarch butterflies. “More than half of all animal species are insects, and they are extremely important for many things, from health to ecology,” he says.

De Roode hopes to develop the class to include a field trip to the Ecuadorian Amazon. Meanwhile, he says, the insects that the students collected and the posters they made will be on display near introductory biology classes “so other students can learn and be inspired by this work.”

Credits: Luna moth by Shawn Hanrahan; insect snacks and Daniel Hueh photos by Carol Clark; Alycia Patton photo by Malia Escobar; field trip photo by Jaap de Roode.

Related:
Lack of respect for insects bugs a biologist
Monarch butterflies use drugs
What aphids can teach us about immunity 

Godzilla: King of the tracemakers

Still taken from original 1954 Godzilla (Gojira), showing a bipedal trackway going from a terrestrial to marine environment. But also check out the prominent groove in the middle of the trackway, caused by a tail dragging behind it, and four forward-pointing toes on each foot.

Emory paleontologist Anthony Martin, who studies tracks, burrows and other traces of life, has written an ichnology review of the new movie “Godzilla” for his blog, “Life Traces of the Georgia Coast.” Below is an excerpt.

"Upon learning that Godzilla would be making its way back onto movie screens this summer, my first thought was not about whether it would it would serve as a powerful allegory exploring the consequences of nuclear power. Nor did I wonder if it would be a metaphor of nature cleansing the world’s ecological ills through the deliberate destruction of humanity. Surprisingly, I didn’t even ponder whether the director of this version (Gareth Edwards) would have our hero incinerate Matthew Broderick with a radioactively fueled exhalation as cinematic penance for the 1998 version of Godzilla.

"Instead, my first thought was, 'Wow, I’ll bet Godzilla will leave some awesome tracks!' My second thought was, 'Wow, I’ll bet Godzilla will leave some awesome bite and claw marks!' My third thought was, 'Wow, I’ll bet Godzilla will leave some awesome feces!' All of these musings could be summarized as, 'Wow, I’ll bet Godzilla will leave awesome traces, no matter what!'

"So as an ichnologist who is deeply concerned that movie monsters make plenty of tracks and other traces whilst rampaging, I am happy to report that yes, this Godzilla and its kaiju compatriots did indeed make some grand traces. Could they have made traces worthy of ichnological appraisal, ones that could be readily compared to trace fossils made by Godzilla’s ancestors? Yes, but these traces could have been better, and let me explain why."

Read the entire review on Martin’s blog.


Related:
Bringing to life "Dinosaurs Without Bones"
Dinosaur burrows yield clues to climate change

Confessions of a turtle freak

It's World Turtle Day! Time to come out of your shell and celebrate with other turtle lovers. (Illustration by Jason Raish.)

By Nancy Sedieman, Emory Magazine

I am a turtle freak.

It’s not a label I readily accepted six years ago as I sat among researchers and conservationists in a Savannah conference center, scribbling notes on presentations delivered at the International Sea Turtle Symposium.

One of the speakers made an offhand comment about turtle “freaks” or groupies who attend the symposium with the primary goal of snapping up an array of turtle-themed items from around the world that were sold in the vendor marketplace. I was insulted.

True, I was not technically a sea turtle researcher, but I had spent all night on Florida beaches on turtle patrols, accompanying researchers as they tagged nesting loggerheads and leatherbacks. I had written about their work, read scientific papers on satellite telemetry, loggerhead hatchling mortality, and the migratory behavior of male hawksbills in the Caribbean. Archie Carr was one of my heroes.

Okay, I was one of few “researchers” in the audience who was wearing a loggerhead T-shirt and silver turtle charms that dangled from my earrings, bracelet, and necklace. And yes, my research notebook did have a leatherback turtle embossed on it. But my attire certainly did not mean that I was some sort of fanatic.

My choice in home decor . . . well, perhaps that tells a different story. I survey what I can see from my vantage point on the couch. There’s the loggerhead tea candle stand, the Buddha in the form of a turtle, a framed oil painting of Madagascan flat-tailed tortoises, a jeweled turtle something, a turtle crossing sign . . . and we haven’t left the living room yet.

I am resigned to the fact that when I pass from this life, the headline will read: “Woman Survived by 189 Turtle Figurines.”

What is it about me and turtles? Why does my heart lift whenever I see one of those (even I have to admit) unearthly looking creatures?

It all began at Emory with my exploration of the Lullwater Preserve. What started as a fun pastime—finding box turtles in the deep forest, catching glimpses of soft-shell turtles lurking at the bottle of the creek, and chuckling at painted turtles who managed to wedge themselves in the most unlikely positions in the lakeside brush—led me to wonder about their habits and habitats. Noting my budding interest in turtles, former environmental studies undergraduate Mandy Schmitt Mahoney generously invited me to join her and researchers from other universities in monitoring nesting sea turtles along the Florida coast.

Read the whole article in Emory Magazine.