Getty Images/Tom Ervin
One of the most prolific killers in the animal kingdom isn't big, toothy, or particularly fast. It's an insect that can fit on your fingertip.
Mosquitoes are responsible for millions of deaths each year through the spread of diseases like malaria, dengue fever, and West Nile virus.
Malaria, a flu-like illness caused by parasites that only mosquitoes carry, infected 219 million people in 2010 and killed 660,000, according to the World Health Organization.
According to American Mosquito Control Association technical advisor Joe Conlon, malaria kills the equivalent of nine Boeing 747s full of children every year.
"Now think about what the headlines would read if we had nine airlines crashing in the jungle every day and killing all the children," Conlon told Business Insider.
Fortunately, malaria is treatable. But many other mosquito-borne illnesses — some that haven't yet reached the United States — don't have proven antidotes.
"The nastiest diseases on the planet are only a 7-hour plane ride away," Conlon said.
Below are some of the worst mosquito-borne illnesses. Currently, none of them have any treatments or vaccines.
Rift Valley Fever can infect both people and animals."If it ever got into the United States, our cattle industry would just go down the tank," Conlon said. On top of that, people usually contract the virus by eating infected meat.
RFV only causes death in 1% of cases but causes nasty effects nonetheless. Some vomit blood, and half who contract the ocular form will go blind. The disease hasn't breached the United States yet, but according to Conlon, we have the perfect conditions.
Symptoms: Some cases have no symptoms while others experience fever, generalized weakness, back pain, and dizziness. About 1% of cases turn hemorrhagic.
Incubation: 2 to 7 days.
Fatality: About 1% of cases.
Chikungunya affects millions worldwide. Conlon calls the fever an "all-body Charlie horse." It's rarely fatal but affects children especially horrifically.
"I've been in Africa and seen and heard children just screaming for days on end because of the pain. It's a really pathetic, nasty disease," Conlon said. He added most cases are reported in the Indian ocean basin, but a few have popped up in the last couple years in Northern Italy — a climate similar to the U.S.
Symptoms: fever, headache, fatigue, nausea, vomiting, muscle pain, rash, and joint pain.
Incubation: 2 to 12 days, but usually 3 to 7.
Fatality: Rarely fatal.
Florida has also seen recent outbreaks of Dengue fever, also known as break bone fever. "It feels like all the bones in your body are broken," Conlon said.
The disease becomes much more worrisome the second time around. If someone contracts a different strain again, the disease morphs into the hemorrhagic form, meaning they start bleeding from every orifice of their body. That state likely results in death, especially in children.
If anything, Dengue fever proves that mosquito-borne illnesses aren't confined to tropical areas, like many people think. In fact, the first case of the disease was discovered in Philadelphia, according to Conlon. "These diseases do very, very well in temperate climates," he added.
Symptoms: high fever and at least two of the following: severe headache, severe eye pain, joint pain, muscle and/or bone pain, rash, nosebleeds, low white cell count.
Incubation: 2 to 7 days.
Fatality: Less than 1%.
For every case of West Nile Virus that we see, authorities say there are at least 35 undocumented cases, according to Conlon. That means the 35,000 documented cases of West Nile since 1999 really translates into millions, he says.
Symptoms: 70 to 80% of people show no symptoms, but the rest experience headache, body aches, joint pains, vomiting, diarrhea, or rash.
Incubation: 2 to 14 days, but usually 2 to 6.
Fatality: Less than 1% develop the neuro-invasive form (encephalitis or meningitis).
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