The military is worried about mosquitoes because soldiers who contract insect-borne diseases such as malaria, Zika and viral encephalitis are all soldiers who cannot participate in combat. Research conducted at WRAIR has helped develop insect repellents and vaccines.
“We call it force preservation,” he said. Lieutenant Colonel Elizabeth Wanjadirector of WRAIR’s entomology department.
To learn how mosquitoes spread diseases and to develop and test vaccines against those diseases, we need a reliable supply of mosquitoes. WRAIR currently houses six species of animals, including: Aedes aegypti, Aedes albopictusthree types: Anopheles mosquito and Culex mosquito.
Along one wall of the brightly lit insectarium are shelves, each containing large shallow pots containing a few inches of water. Add small mosquito eggs (it reminded me of ground black pepper) to the water. The eggs hatch and develop into larvae. The larvae are fed fish food, then fished out and placed in white plastic buckets on a shelf on the opposite wall. There, under a fine mesh screen, it develops into a pupa, similar to the tadpole stage of a mosquito.
When I held my hand over a bucket, hundreds of tiny black commas floated inside and rippled like a babbling starling.
“We call them tumblers,” Wanja said of the chrysalises that rolled in surprise at my shadow. It was one of the creepiest things I’ve ever seen.
It takes about a week for the eggs to develop into adults.
If you’re studying mosquito-borne diseases, all you need is a female mosquito that needs blood to lay eggs. Females are strongly attracted to heat, so it’s better to find a live animal to chew on, so insect watchers shine a heat source on a bucket to separate males and females.
And to feed them? Donated human blood is placed in a small glass cup sealed with a membrane. Pressing the membrane against the mesh screen is like ringing a dinner bell. The mosquito gets up and starts drinking water.
When you buy eggs at the supermarket, each carton contains 12 eggs. If you get Mosquitoes from the Insectarium, you will get 250 per bucket. Researchers can test vaccines on volunteers by giving them malaria-infected blood.
How do we enter the world of mosquitoes in the first place? tobin roland I’m the head of the insect department. After joining the Army in 2003 as a medical laboratory technician, his first assignment was in his WRAIR insect room.
“I fell in love with it,” said Roland, now a civilian.
Wanja grew up in Kenya and became fascinated with insects as a young girl. She was completing her PhD in entomology in 1998 when terrorists bombed the US Embassy in Nairobi. Her relatives were among those killed. Wanja was thinking about how she could use her skills against terrorists. Fighting mosquitoes was her answer.
“This was one of the ways I could step in and actually help the military and get them out,” she said.
In 2007 and 2008, Wanja spent 15 months in Iraq studying insects and how to deal with them.
How do people react when Wanja and Roland describe their work?
“I think the most common response is: ‘You make a living playing with bugs?’ That’s not a job,” Roland said. “Most people don’t really understand the threat associated with insects.”
It’s not just from mosquitoes. The insectarium also houses sand flies, which can bite even worse than mosquitoes. Stable flies are creatures that feed in “pools.” Rather than piercing the skin with a proboscis like a hypodermic needle, they use their mouthparts to cut into tissue and suck blood that bubbles to the surface. In the process, they can transmit leishmaniasis and sandfly fever.
The scope of tropical diseases appears to be expanding due to global warming. And new threats are looming.
“Ticks are starting to become the main problem,” Wanja says. “We’re discovering previously unknown pathogens in ticks.”
That means WRAIR needs to study them. Soon, the legs of tiny ticks will be flapping into the insectarium.
