Summer is in full swing, with people in Illinois and all over the country getting outside and soaking up some sun. Unfortunately, with the arrival of warm weather comes one major downside: mosquitoes. These pests not only have an annoying bite, but have been carriers of diseases harmful to humans for centuries. In the U.S., we’re lucky that we only have to worry about a cloud of mosquitoes ruining an outdoor party or picnic – for other parts of the world, especially underdeveloped countries, the battle with these persistent pests is one of life and death. At Terminix Anderson, we’re experts at keeping mosquitoes under control in Illinois – but to defeat your enemy, you must know your enemy. Read on to learn more about the potential dangers mosquitoes carry and what steps science is taking to stop them.
An Ancient, Bloodthirsty Opponent
Mosquitoes may be in the news a lot lately, but they’ve been a pest for quite some time. The oldest known mosquito that most closely resembles the modern species was discovered in Canada, trapped in amber dated from the Cretaceous period approximately 79 million years ago. An older, more primitive species was found in Burmese amber dating as far back as 90 to 100 million years, but scientists believe that mosquitoes have evolved very little as a species in the last 40 to 50 million years. It’s easy to see how such a creature seems almost created specifically to be perfectly evil.
Humans have been fighting a protracted war with these pests for much of our history, but it wasn’t until the rise of colonialism that their true crime – the spreading of disease – started to become an issue. To most people, malaria or yellow fever sound like things an old-world adventurer would contract while exploring the dense Amazon jungle, but it’s a day-to-day worry for much of the world. Over 40 percent of the world’s population, in about 91 countries, is at risk for malaria, with 500 million cases occurring each year (according to the World Health Organization).
To our credit, humankind has tried its best to fight back against mosquitoes as best we can, with varying results – to give you an idea of how bad summers used to be, window screens weren’t invented until the 1880s, and modern electrical air conditioning wasn’t commercially affordable until post-World War II. You can see why something as simple as wire mesh was hailed as “the most human contribution the 19th century made to the preservation of sanity and good temper.” Science has made some strides since then, particularly in the field of mosquito repellents, but as we’ve discussed in a previous article, there’s still no method that’s 100 percent effective.
Why Are Mosquitoes So Good at Transmitting Diseases?
Because of the way they feed, mosquitoes are extremely efficient at spreading illness and disease among humans and animals alike. Of the 14,000 infectious microorganisms known to science, about 600 are shared between animals and humans. Normally, these infections require you to be exposed to blood from a contaminated person or animal – not something the average person would worry about. But here’s why mosquitoes are so dangerous: By feeding on the blood of animals and humans alike, they act as a bridge between the two parties, even when they’re nowhere near each other. And they do it all without even being noticed.
If you’ve ever been bitten by a mosquito – and it would be a small miracle if you haven’t – you already know it’s incredibly difficult to catch one in the act. This is because these pests have evolved over time to perfect their methods, ensuring that they can suck as much blood as possible without being swatted. Interestingly, only female mosquitoes bite, and the blood they suck is used to feed the eggs inside them before they are laid.
When they land on your skin, mosquitoes use their mouth part, called a proboscis, to pierce it like a hypodermic needle. They immediately inject their saliva into the wound, which acts as an anti-inflammatory and anti-coagulant. Though the proboscis is rigid enough to pierce the skin, it then becomes flexible enough to root around inside your dermis to find capillaries full of delicious blood. Once they find one, they make sure to drink their fill. On average, a mosquito spends up to four minutes sucking blood! Even vampires think that’s greedy.
The Sinister Six Mosquito-Borne Illnesses
It is through their saliva that a mosquito transmits disease. Even though they may be carrying contaminated blood, mosquitoes themselves are not affected, which seems cosmically unfair. Malaria is still the big name when it comes to mosquito-borne illnesses, but there are several others that are just as dangerous:
Chikungunya
A viral infection most commonly found in countries in Africa, Asia, Europe, and the Indian and Pacific Oceans. In 2013, the virus was first spotted in the Western Hemisphere on an island in the Caribbean. Symptoms include fever, joint pain and swelling, muscle pain, and rash. No vaccine or medicine currently exists for chikungunya.
Dengue Fever
This virus sees 20 million cases of infection a year in more than 100 countries around the globe. In 1995, a dengue epidemic struck 14 countries in Latin America and the Caribbean, resulting in 200,000 cases alone. Symptoms include fever, headaches, vomiting, muscle and joint pain, and rash. In some cases, it can develop into dengue hemorrhagic fever, a life-threatening condition resulting in uncontrollable bleeding and dangerously low blood pressure. Just last year, a partially effective dengue vaccine became commercially available, but results are inconclusive at best.
Filariasis
A little-known condition caused by mosquitoes carrying the parasitic filariasis worm, which can cause disfigurement marked by massive swelling in parts of the body. It’s estimated that around 40 million people currently live with some sort of filariasis disability. Preventative chemotherapy has been shown to be an effective, if expensive, method of eliminating the infectious worm.
West Nile Fever
Found in temperate and tropical regions of the world, West Nile was first discovered in Uganda in 1937. It wasn’t considered a major threat to humans until consecutive outbreaks occurred in Algeria in 1994 and Romania in 1996. You may remember hearing about it in breathless, panicky news reports in the U.S. after it was accidentally introduced to our shores in 1999 from Americans traveling abroad. By 2003, West Nile had spread to almost every state, with over 3,000 cases reported in 2006.
Though this virus is still dangerous, much of the panic over its arrival was overblown. Nearly 80 percent of infected humans show few or no symptoms, which are the standard fever, headaches, muscle and joint pain, nausea, vomiting, and rash. Those with compromised immune systems, or the elderly, are at higher risk of neurological disorders, specifically encephalitis and poliomyelitis – inflammation of the spinal cord.
Yellow Fever
Compared to most other mosquito-borne illnesses, this one has a relatively short duration; symptoms typically improve within five days. But in countries with limited access to proper health care, it can be much harder to recover. In 2013, over 127,000 severe infections were reported, with 45,000 deaths occurring from yellow fever. It’s most common in tropical areas like South America and Africa, but has been reported in North America and Europe as well.
The name comes from serious infections causing liver damage, which leads to a yellowing of the skin. In 1927, it was the first human virus to be isolated by scientists in order to develop a vaccine. According to the WHO, a single vaccination is enough to protect you from infection for life.
Zika
The latest illness to be covered to death by 24-hour news networks, Zika has actually been around for some time. It was first discovered in the Zika Forest of Uganda, where it got its name, in 1947. It remained mostly in a narrow equatorial belt from central Africa to southeast Asia until about 2007, when the virus began to spread across the Pacific Ocean to the Americas. The threat of Zika was a looming shadow over the 2016 Summer Olympics in Rio de Janeiro, Brazil, and soon after that Americans traveling abroad brought Zika to south Illinois and Indiana.
The reason this virus is so easily spread is because it often has little to no visible symptoms, like a mild form of dengue fever. However, Zika is a significant risk for pregnant women, as science has shown they can pass along the infection to their unborn child, which can lead to birth defects like microcephaly and other complications. This disease is most commonly spread through sexual transmission, which is how the majority of cases in the U.S. have originated.
Science Steps Up to Fight Back
It’s hard to believe, but most of the aforementioned diseases are carried by only two types of mosquito: Aedes aegypti and Aedes albopictus. Because these mosquitoes are such a threat to millions of humans across the globe, science has begun to fight back against these pests. While vaccines have been doing much of the protecting lately, they’re not always perfect, and in some parts of the world nearly impossible to access. Lately, scientists have decided to approach the problem another way – by attacking it at the source.
First, there’s the Sterile Insect Technique (SIT), wherein captured male mosquitoes are irradiated to make them sterile (hence the name). They are then released back into the wild to mate, and when the female doesn’t produce offspring, their population is slowly reduced over time. As you’ve probably guessed, it’s not a quick solution, but it’s been proven to completely eradicate other insects, like the screw-worm fly in the U.S. and Mexican fruit fly in northern Mexico.
The other popular method being introduced around the world uses the latest in technology to fight the threat of mosquitoes. Using a process called “Clustered Regularly Interspaced Short Palindromic Repeat” or CRISPR, scientists can easily alter DNA sequences and modify the genomes of bacteria and other microorganisms. With a CRISPR technique called a “gene drive,” they can pick and choose the traits that are spread through wild populations of animals.
For instance, if you altered a mosquito’s DNA to say that any female who mates with it will only produce male (non-biting) mosquitoes, or to say that those mosquitoes will now no longer be able to carry the malaria virus, you have effectively lowered the instances of both mosquitoes and the spread of malaria. While this gene-manipulation process has raised some ethical concerns, it has the potential to radically shift the fight against mosquito-borne illnesses across the globe.
Bill and Melinda Gates have funded a project called Target Malaria that uses CRISPR to cause malaria-carrying mosquitoes to become sterile and eventually die out. And the U.S. Food and Drug Administration has approved the release of genetically modified mosquitoes in Illinois and Indiana, with the promise that the experimental trial would have “no significant” environmental impact. Whether this is the beginning of the end for disease-carrying mosquitoes, or just another flash in the pan, remains to be seen.
Terminix Anderson Controls Mosquitoes in Illinois and More
Though there is a lot of talk lately about Zika and West Nile virus in America, your chances of being infected (and of serious complications from that infection) are very low. As this article has shown, mosquito-borne illnesses are most dangerous in countries where people don’t have access to repellents and medicine necessary to keep them safe. Perhaps new technologies like SIT or CRISPR will offer cheaper, more effective methods of controlling mosquitoes and their ability to spread disease, but it will take time for these techniques to pan out.
In the meantime, if you are traveling to areas where mosquitoes are more active – like the southern U.S., Mexico, and other more tropical locations – do your part to halt the spread of Zika and other viruses by using proper mosquito prevention techniques.
Even if you’re not traveling, it’s still smart to practice mosquito control. At Terminix Anderson Pest, we have the experience necessary to implement precision pest control that is safe for you and your family. We’ll inspect your property for breeding locations and help you eliminate local mosquitoes safely and effectively, so you can get back to soaking up the summer sun again. Contact Terminix Anderson today and ask about our mosquito control services.
